CN110233063B

CN110233063B - Advanced electrolyte system and use thereof in energy storage devices

Info

Publication number: CN110233063B
Application number: CN201910288116.2A
Authority: CN
Inventors: 里卡尔多·西尼奥雷利; 约翰·J·库利; 克里斯托弗·约翰·西巴尔德·迪恩; 詹姆斯·爱泼斯坦; 帕德马纳班·萨斯桑·库蒂皮莱; 法布里齐奥·马丁尼; 林赛·A·威廉默斯
Original assignee: Fastcap Systems Corp
Current assignee: Nano Ramic Corp.
Priority date: 2012-02-24
Filing date: 2013-02-25
Publication date: 2022-01-04
Anticipated expiration: 2033-02-25
Also published as: IL298172A; CN110233063A; IL316198A; IL234232B; IL298172B1; CN104246942A; CA2865230A1; CN104246942B; WO2013126915A1; KR20250022231A; AU2013222120A1; IL234232A; JP2015515741A; EP2817810A1; EP2817810A4; KR20210097812A; KR20220149761A; IL234232B2; KR20140129283A; KR102461542B1

Abstract

The present invention provides an advanced electrolyte system and its use in an energy storage device comprising an energy storage cell immersed in the advanced electrolyte system and disposed within a hermetically sealed housing, the cell being electrically coupled to a positive contact and a negative contact, wherein the ultracapacitor is configured to output electrical energy in a temperature range of about -40 degrees Celsius to about 210 degrees Celsius. The invention also provides for its manufacture and use.

Description

Advanced electrolyte system and use thereof in energy storage devices

The present application is a divisional application of a chinese patent application with application number 201380022019.X entitled "advanced electrolyte system and its use in energy storage devices", the patent application 201380022019.X being a national application entering the chinese national phase according to the patent cooperation treaty about international application (PCT/US2013/027697) filed in 2013, 2 month and 25 day.

Cross Reference to Related Applications

The present application claims priority benefits of U.S. provisional patent application No. 61/602,713 entitled "Electrolytes for Ultracapacitors (Electrolytes for Ultracapacitors)" filed on 24/2/2012, international application No. PCT/US2012/045994 entitled "High Temperature Energy Storage devices" filed on 9/7/2012, Power Supply for Downhole Instruments (Power Supply filed on 19/7/2012, and U.S. application No. 13/553,716 filed on 9/11/2012, and U.S. provisional patent application No. 61/724,775 entitled "Electrolytes for Ultracapacitors (Electrolytes for Ultracapacitors)". Each of these disclosures is incorporated herein by reference.

Technical Field

The invention disclosed herein relates to energy storage cells, in particular to advanced electrolyte systems for use in these energy storage cells, and related techniques for providing electric double layer capacitors operable at high temperatures.

Background

Energy storage units are ubiquitous in our society. Although most people consider the energy storage unit simply as a "battery," other types of units should be included within this scope. For example, supercapacitors have recently received attention for their advantageous properties. In short, many types of energy storage units are known today and are in use.

An electric double layer capacitor, also called a "supercapacitor (supercapacitor, ultracapacitor)", "pseudocapacitor", or "electrochemical electric double layer capacitor", is a capacitor that exhibits significantly improved performance over conventional capacitors. One such parameter is energy density. Generally, the energy density of supercapacitors is on the order of thousands of times higher than that of high capacity electrolytic capacitors.

Capacitors are one of the key components in any electronic device and electronic system. Conventional functions include supply voltage smoothing, providing support to the energy source, and filtering. There are many industries that have a need for implementing electronic devices and capacitors.

Consider, for example, industries having applications that require electrical components to operate continuously at high temperatures (e.g., at temperatures in excess of 80 degrees celsius), such as the oil drilling, aerospace, aviation, military, and automotive industries. This thermal exposure, along with various factors, causes performance degradation of the energy storage system at elevated temperatures and leads to premature degradation of the energy storage unit. Durability and safety are key requirements in typical aerospace and defense applications. Such as those in which the engine, turbofan and control and sensing electronics are disposed near the rocket engine case. Automotive applications such as small transmissions or embedded alternator/starters also require durability and long life at elevated temperatures.

Electronic components used in industrial environments must be physically robust while meeting performance requirements. One of the attendant challenges for designers and manufacturers of supercapacitors is to obtain an electrolyte that can function well and reliably at high temperatures, as well as an electrolyte that can function well and reliably at both high and low temperatures. Unfortunately, the desired properties of some electrolytes cannot be exhibited or sustained at higher temperatures, and even those electrolytes that have achieved durability at high temperatures cannot reliably operate at low temperatures. Thus, what is needed is an electrolyte for a supercapacitor that performs well under demanding conditions. Preferably, the electrolyte provides stable conductivity and low internal resistance and stable and high capacitance, and stable and low leakage current over a wide range of temperatures.

Disclosure of Invention

In one embodiment, a supercapacitor is disclosed. The ultracapacitor includes an energy storage cell and an Advanced Electrolyte System (AES) within a hermetically sealed housing, the cell electrically coupled to a positive contact and a negative contact, wherein the ultracapacitor is configured to operate at a temperature within a temperature range of about-40 degrees celsius to about 210 degrees celsius.

In another embodiment, a method for manufacturing a supercapacitor is provided. The method comprises the following steps: disposing an energy storage unit comprising an energy storage medium within a housing; and filling the case with an Advanced Electrolyte System (AES) such that the ultracapacitor is manufactured to operate at a temperature range of about-40 degrees celsius to about 210 degrees celsius.

In yet another embodiment, a method of using a High Temperature Rechargeable Energy Storage Device (HTRESD) is provided. The method comprises the following steps: obtaining an HTRESD comprising an Advanced Electrolyte System (AES); and cycling the HTRESD by alternately charging and discharging the HTRESD at least twice while maintaining a voltage across the HTRESD such that the HTRESD exhibits an initial peak power density of 0.01W/liter to 150 kW/liter such that the HTRESD operates at an ambient temperature that is a temperature within a temperature range of about-40 degrees celsius to about 210 degrees celsius.

In yet another embodiment, a method of using a supercapacitor is provided. The method comprises the following steps: obtaining a supercapacitor as described herein, wherein the supercapacitor exhibits a volumetric leakage current (mA/cc) of less than about 10 mA/cc when held at a substantially constant temperature in a range between about 100 degrees celsius and about 150 degrees celsius; and cycling the supercapacitor by alternately charging and discharging the supercapacitor at least twice while maintaining a voltage across the supercapacitor such that the supercapacitor exhibits an ESR increase less than about 1000% after at least 1 hour when held at a substantially constant temperature in a range between about-40 degrees celsius to about 210 degrees celsius.

In another embodiment, a method of providing a high temperature rechargeable energy storage device to a user is provided. The method comprises the following steps: selecting a High Temperature Rechargeable Energy Storage Device (HTRESD) comprising an Advanced Electrolyte System (AES) that exhibits an initial peak power density of between 0.01W/liter and 100 kW/liter and an endurance life of at least 1 hour when exposed to an ambient temperature within a temperature range of about-40 degrees Celsius to about 210 degrees Celsius; and delivering the storage device such that the HTRESD is provided to a user.

In yet another embodiment, a method of providing a high temperature rechargeable energy storage device to a user is provided. The method comprises the following steps: obtaining any of the supercapacitors as described herein that exhibit a volumetric leakage current (mA/cubic centimeter) that remains below about 10 mA/cubic centimeter at a substantially constant temperature in a range between about-40 degrees celsius and about 210 degrees celsius; and delivering the storage device such that the HTRESD is provided to a user.

In yet another embodiment, an Advanced Electrolyte System (AES) is disclosed. The AES comprises an ionic liquid comprising at least one cation and at least one anion and exhibits a halide ion content of less than 1000ppm and a water content of less than 100 ppm.

In yet another embodiment, an Advanced Electrolyte System (AES) is disclosed. The AES comprises an ionic liquid comprising at least one cation and at least one anion and at least one solvent and exhibits a halide ion content of less than 1000ppm and a water content of less than 1000 ppm.

Drawings

The foregoing and other features and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings, which are not to be taken in a limiting sense:

FIG. 1 illustrates aspects of an exemplary ultracapacitor;

FIG. 2 is a block diagram depicting a plurality of Carbon Nanotubes (CNTs) grown onto a substrate;

FIG. 3 is a block diagram depicting the deposition of a current collector onto the CNTs of FIG. 3 to provide an electrode element;

FIG. 4 is a block diagram depicting the addition of a transfer tape to the electrode element of FIG. 3;

FIG. 5 is a block diagram depicting an electrode element during a transfer process;

FIG. 6 is a block diagram depicting the electrode element after transfer;

FIG. 7 is a block diagram depicting an exemplary electrode fabricated from a plurality of electrode elements;

FIG. 8 depicts an embodiment of a primary structure of a cation that may be included in an exemplary supercapacitor;

fig. 9 and 10 provide comparative data for exemplary supercapacitors utilizing virgin electrolyte and purified electrolyte, respectively;

fig. 11 depicts an embodiment of a housing of an exemplary ultracapacitor;

FIG. 12 illustrates an embodiment of a storage cell of an exemplary ultracapacitor;

FIG. 13 depicts a blocker disposed on the interior of the body of the housing;

14A and 14B (collectively referred to herein as FIG. 14) depict aspects of a cover of a housing;

FIG. 15 depicts an assembly of supercapacitors according to the teachings herein;

fig. 16A and 16B (collectively referred to herein as fig. 16) are graphs depicting the performance of an embodiment of an ultracapacitor without a barrier and a similar embodiment including a barrier, respectively;

fig. 17 depicts a barrier disposed as a wrap around the storage unit;

18A, 18B, and 18C (collectively referred to herein as FIG. 18) depict embodiments of a cover comprising a layered material;

FIG. 19 is a cross-sectional view of an electrode assembly including a glass-to-metal seal (glass-to-metal seal);

FIG. 20 is a cross-sectional view of the electrode assembly of FIG. 19 mounted in the cap of FIG. 18B;

FIG. 21 depicts the arrangement of energy storage units in an assembly;

22A, 22B, and 22C (collectively referred to herein as FIG. 22) depict an embodiment of an assembled energy storage unit;

FIG. 23 depicts the incorporation of a polymer insulator into a supercapacitor;

24A, 24B, and 24C (collectively referred to herein as FIG. 24) depict aspects of a template for another embodiment of a cover for an energy storage device;

FIG. 25 is a perspective view of an electrode assembly comprising a hemispherical material;

FIG. 26 is a perspective view of a cover including the electrode assembly of FIG. 25 mounted in the template of FIG. 24;

FIG. 27 is a cross-sectional view of the cover of FIG. 26;

FIG. 28 depicts the coupling of the electrode assembly to the terminals of the storage unit;

FIG. 29 is a transparent isometric view of an energy storage unit disposed within a cylindrical housing;

FIG. 30 is a side view of a storage unit showing the layers of one embodiment;

FIG. 31 is an isometric view of a rolled up storage unit including reference marks for arranging a plurality of leads;

FIG. 32 is an isometric view of the storage unit of FIG. 31 once deployed;

FIG. 33 depicts a rolled storage unit containing a plurality of leads;

FIG. 34 depicts a Z-fold imparted to aligned leads (i.e., terminals) coupled to a storage unit;

FIG. 35, FIG. 36, FIG. 37, FIG. 38 are graphs depicting performance of an exemplary ultracapacitor; and

fig. 39, 40, 41, 42, 43 are graphs depicting performance of an exemplary ultracapacitor at 210 degrees celsius.

Fig. 44A and 44B depict a cell having a novel electrolyte entity: 1-butyl-1-methylpiperidine

Capacitance curve and ESR curve of the performance of a supercapacitor of bis (trifluoromethylsulfonyl) imide at 150 degrees celsius and 1.5V.

FIGS. 45A and 45B depict trihexyltetradecyl with novel electrolyte entities

Fig. 46A and 46B are capacitance curves and ESR curves depicting the performance of a supercapacitor with the novel electrolyte entity butyltrimethylammonium bis (trifluoromethylsulfonyl) imide at 150 degrees celsius and 1.5V, respectively.

Fig. 47A and 47B are capacitance curves and ESR curves depicting the performance of a supercapacitor with an ionic liquid selected from the ionic liquids used in preparing the enhanced electrolyte combination at 125 degrees celsius and 1.5V, respectively.

Fig. 48A and 48B are a capacitance curve and an ESR curve depicting the performance of a supercapacitor with 37.5% organic solvent-ionic liquid (as in fig. 47) V/V at 125 degrees celsius and 1.5V, respectively.

FIG. 49 is an ESR curve depicting the performance of a supercapacitor with 37.5% organic solvent-ionic liquid (as in FIG. 47) V/V at-40 degrees Celsius and 1.5V.

Detailed Description

Various variables are described herein, including but not limited to composition (e.g., electrode materials, electrolytes, etc.), conditions (e.g., temperature, degrees of freedom for various impurities at various levels), and performance characteristics (e.g., post-cycle capacitance relative to initial capacitance, low leakage current, etc.). It should be understood that any combination of any of these variables may define an embodiment of the present invention. For example, embodiments of the invention are specific electrode materials, combinations with specific dielectrics, combinations at specific temperature ranges and with less than a specific amount of impurities, operation with post-cycle capacitance, and leakage currents of specific values (these variables are included as much as possible but may not be emphasized for specific combinations). Other combinations of articles, compositions, conditions, and/or methods may also be specifically selected from among the variables listed herein to define other embodiments, as will be apparent to those of skill in the art.

The invention, including the advanced electrolyte system and its use, will be described with reference to the following definitions set out below for convenience. Unless otherwise indicated, the following terms are used herein as defined below:

I. definition of

When introducing elements of the present invention or the embodiments thereof, where the noun is not preceded by a quantitative term, it is intended to include both the singular and the plural. Similarly, when the adjective "another" is used to modify an element, it is intended to include both the singular and the plural. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements.

The terms "alkenyl" and "alkynyl" are art-recognized and refer to unsaturated aliphatic groups similar in length and possible substitution to the alkyl groups described below, but containing at least one double or triple bond, respectively.

The term "alkyl" is art-recognized and can include saturated aliphatic groups including straight-chain alkyl groups, branched-chain alkyl groups, cycloalkyl (alicyclic) groups, alkyl-substituted cycloalkyl groups, and cycloalkyl-substituted alkyl groups. In certain embodiments, the linear or branched alkyl group has about 20 or fewer carbon atoms in its backbone (e.g., linear C)₁-C₂₀C of a branched chain₁-C₂₀). Likewise, cycloalkyl groups have from about 3 to about 10 carbon atoms in their ring structure, or alternatively about 5, 6, or 7 carbons in the ring structure. Examples of alkyl groups include, but are not limited to, methyl, ethyl, propyl, butyl, pentyl, hexyl, ethylhexyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and the like.

The terms "cladding", and the like as used herein refer to joining different metals together. Cladding is often accomplished by extruding the two metals through a die and pressing or rolling the sheet together under high pressure. Other methods, such as laser cladding, may be used. The result is a sheet of material that is constructed from multiple layers, where the multiple layers of material are joined together so that the material can work together as a single sheet (e.g., formed as a uniform sheet of material).

By convention, it is believed that a "contaminant" may be defined as any undesirable material that, if introduced, would adversely affect the performance of the ultracapacitor 10. It should also be noted that, in general, the contaminants may be evaluated herein in terms of concentration, such as parts per million (ppm). The concentration may be by weight, by volume, by weight of the sample, or in any other way to determine suitability.

The term "cyano" is given its ordinary meaning in the art and refers to the group CN. The term "sulfate" is given its usual meaning in the art and refers to the group SO₂. The term "sulfonic acid group" is given its usual meaning in the art and refers to the group SO₃X, wherein X can be an electron pair, hydrogen, alkyl, or cycloalkyl. The term "carbonyl" is known in the art and refers to the group C ═ O.

In general, the term "electrode" refers to an electrical conductor used to make contact with another material, often a non-metal, in a device that can be incorporated into an electrical circuit. In general, the term "electrode" as used herein relates to the current collector 2 and additional components (e.g., energy storage medium 1) that may accompany the current collector 2 to provide the desired functionality (e.g., energy storage medium 1 matched to the current collector 2 to provide energy storage and energy transfer).

"energy density" is the square of the peak device voltage times one-half of the device capacitance divided by the mass or volume of the device.

As discussed herein, "hermetic" refers to a seal whose properties (i.e., leak rate) are defined in units of "atm-cubic centimeters per second," which means 1 cubic centimeter per second of gas (e.g., He) at ambient atmospheric pressure and temperature. This is equivalent to the expression in units of "standard He-cubic centimeters per second". Further, 1 atm-cubic centimeter/sec is considered to be equal to 1.01325 millibar-liter/sec.

The terms "heteroalkenyl" and "heteroalkynyl" are known in the art and refer to alkenyl and alkynyl groups as described herein in which one or more of the atoms is a heteroatom (e.g., oxygen, nitrogen, sulfur, etc.).

The term "heteroalkyl" is known in the art and refers to an alkyl group as described herein in which one or more atoms are heteroatoms (e.g., oxygen, nitrogen, sulfur, etc.). For example, an alkoxy (e.g., -OR) is a heteroalkyl.

By convention, the terms "internal resistance" and "effective series resistance" and "ESR," terms known in the art to represent resistance aspects of the device, are used interchangeably herein.

By convention, the term "leakage current" generally refers to the current drawn by the capacitor measured after a given period of time. The measurement is made while the capacitor terminals are held at a substantially fixed potential difference (terminal voltage). A typical time period is seventy-two (72) hours when evaluating leakage current, but different time periods may also be used. It should be noted that the leakage current of prior art capacitors generally increases with the volume and surface area of the energy storage medium and with the increase of the internal surface area of the housing. In general, an increased leakage current is believed to represent a gradually increasing reaction rate in the supercapacitor 10. The performance requirements for leakage current are generally defined by the environmental conditions prevailing in a particular application. For example, for a supercapacitor 10 having a volume of 20mL, the practical limit of leakage current can be reduced to below 200 mA.

The "lifetime" of a capacitor is also generally defined by the particular application and is often expressed as a certain percentage increase in leakage current or degradation of another parameter (such as capacitance or internal resistance) as appropriate or critical for a given application. For example, in one embodiment, the lifetime of a capacitor in an automotive application may be defined as the time for the leakage current to rise to 200% of its initial (beginning of life, "BOL") value. In another embodiment, the lifetime of a capacitor in oil and gas applications may be defined as the time at which any of the following phenomena occur: the capacitance drops to 50% of its BOL value; the internal resistance rises to 200% of its BOL value; the leakage current rises to 200% of its BOL value. By convention, the terms "durability" and "reliability" of a device as used herein generally relate to the lifetime of the device as defined above.

The "operating temperature range" of a device generally refers to the range of temperatures in which a certain level of performance is maintained and is generally determined for a given application. For example, in one embodiment, an operating temperature range for the oil and gas field may be defined as a temperature range in which the resistance of the device is less than about 1000% of the resistance of the device at 30 degrees celsius and the capacitance is greater than about 10% of the capacitance at 30 degrees celsius.

In some cases, the operating temperature range specification provides a lower limit for the effective temperature and the life specification provides an upper limit for the effective temperature.

"peak power density" is one quarter of the square of the peak device voltage divided by the effective series resistance of the device divided by the mass or volume of the apparatus.

As referred to herein, the "volumetric leakage current" of the supercapacitor 10 generally refers to the leakage current divided by the volume of the supercapacitor 10, and may be expressed, for example, in units of mA/cubic centimeter. Similarly, the "volumetric capacitance" of the supercapacitor 10 generally refers to the capacitance of the supercapacitor 10 divided by the volume of the supercapacitor 10, and may be expressed, for example, in units of F/cubic centimeter. Further, the "volumetric ESR" of the supercapacitor 10 generally refers to the ESR of the supercapacitor 10 multiplied by the volume of the supercapacitor 10, and may be expressed in units of ohm-cubic centimeters, for example.

As a convention, it is considered that the term "may" as used herein is to be understood as optional; "comprising" is understood as not excluding other options (i.e. steps, materials, components, compositions, etc.); "should" does not imply a requirement, but merely an occasional preference or a preference as the case may be. Other similar terms are similarly used in a generally conventional manner.

As discussed herein, terms such as "adjusting," "configuring," and the like can be considered to relate to the application of any of the techniques disclosed herein, as well as other similar techniques (as currently known or later developed), to provide desired results.

Capacitors of the invention

Disclosed herein is a capacitor that provides improved performance over a wide temperature range for the user. For example, the capacitors of the present invention that include the advanced electrolyte systems described herein can operate at temperatures ranging from about as low as-40 degrees celsius to as high as about 210 degrees celsius.

In general, the capacitors of the present invention comprise an energy storage medium suitable for providing a combination of high reliability, wide operating temperature range, high power density and high energy density compared to prior art devices. The capacitor comprises components configured to ensure operation within said temperature range and comprises an electrolyte 6 selected only from the advanced electrolyte systems described herein. The combination of the construction, energy storage media and advanced electrolyte systems provides the robust capacitor(s) of the present invention that are capable of providing operation with enhanced properties over existing capacitors under extreme conditions and with better performance and durability.

Accordingly, the present invention provides a supercapacitor comprising: an energy storage cell and an Advanced Electrolyte System (AES) within a hermetically sealed housing, the cell electrically coupled to the positive contact and the negative contact, wherein the ultracapacitor is configured to operate at a temperature ("operating temperature") within a range of temperatures: about-40 degrees Celsius to about 210 degrees Celsius; about-35 degrees Celsius to about 210 degrees Celsius; about-40 degrees Celsius to about 205 degrees Celsius; about-30 degrees Celsius to about 210 degrees Celsius; about-40 degrees Celsius to about 200 degrees Celsius; about-25 degrees Celsius to about 210 degrees Celsius; about-40 degrees Celsius to about 195 degrees Celsius; about-20 degrees Celsius to about 210 degrees Celsius; about-40 degrees Celsius to about 190 degrees Celsius; about-15 degrees Celsius to about 210 degrees Celsius; about-40 degrees Celsius to about 185 degrees Celsius; about-10 degrees Celsius to about 210 degrees Celsius; about-40 degrees Celsius to about 180 degrees Celsius; about-5 degrees Celsius to about 210 degrees Celsius; about-40 degrees Celsius to about 175 degrees Celsius; about 0 degrees Celsius to about 210 degrees Celsius; about-40 degrees Celsius to about 170 degrees Celsius; about 5 degrees Celsius to about 210 degrees Celsius; about-40 degrees Celsius to about 165 degrees Celsius; about 10 degrees Celsius to about 210 degrees Celsius; about-40 degrees Celsius to about 160 degrees Celsius; about 15 degrees Celsius to about 210 degrees Celsius; about-40 degrees Celsius to about 155 degrees Celsius; about 20 degrees Celsius to about 210 degrees Celsius; about-40 degrees celsius to about 150 degrees celsius.

In a particular embodiment, the AES comprises a Novel Electrolyte Entity (NEE), for example, wherein the NEE is suitable for use in a high temperature supercapacitor. In certain embodiments, the ultracapacitor is configured to operate at a temperature within a temperature range of about 80 degrees celsius to about 210 degrees celsius (e.g., a temperature range of about 80 degrees celsius to about 150 degrees celsius).

In a particular embodiment, the AES comprises a highly purified electrolyte, for example, wherein the highly purified electrolyte is suitable for use in a high temperature supercapacitor. In certain embodiments, the ultracapacitor is configured to operate at a temperature within a temperature range of about 80 degrees celsius to about 210 degrees celsius.

In a particular embodiment, the AES comprises an enhanced electrolyte combination, for example, wherein the enhanced electrolyte combination is suitable for use in both high temperature and low temperature supercapacitors. In certain embodiments, the supercapacitor is configured to operate at a temperature in a temperature range of about-40 degrees celsius to about 150 degrees celsius.

As such, and as noted above, the advantages over existing electrolytes of known energy storage devices are selected from one or more of the following improvements: the total resistance is reduced; improved long term stability of resistance, increased total capacitance, improved long term stability of capacitance, increased energy density, improved voltage stability, reduced vapor pressure, wider temperature range performance of individual capacitors, improved temperature durability of individual capacitors, improved ease of manufacture, and improved cost effectiveness.

In certain embodiments of the supercapacitor, the energy storage cell comprises a positive electrode and a negative electrode.

In certain embodiments of the supercapacitor, at least one of the electrodes comprises a carbonaceous energy storage medium, e.g., wherein the carbonaceous energy storage medium comprises carbon nanotubes. In particular embodiments, the carbonaceous energy storage medium may include at least one of activated carbon, carbon fiber, rayon, graphene, aerogel, carbon cloth, and carbon nanotubes.

In certain embodiments of the supercapacitor, each electrode comprises a current collector.

In certain embodiments of the supercapacitor, the AES is purified to reduce the impurity content. In certain embodiments of the supercapacitor, the amount of halide ions in the electrolyte is less than about 1000 parts per million, for example, less than about 500 parts per million, for example, less than about 100 parts per million, for example, less than about 50 parts per million. In particular embodiments, the halide ions in the electrolyte are selected from one or more of the halide ions selected from chloride, bromide, fluoride and iodide. In particular embodiments, the total concentration of impurities in the electrolyte is less than about 1000 parts per million. In certain embodiments, the impurities are selected from one or more of ethyl bromide, ethyl chloride, 1-bromobutane, 1-chlorobutane, 1-methylimidazole, ethyl acetate and dichloromethane.

In certain embodiments of the supercapacitor, the total concentration of metal species in the electrolyte is less than about 1000 parts per million. In a particular embodiment, the metal species is selected from one or more metals selected from Cd, Co, Cr, Cu, Fe, K, Li, Mo, Na, Ni, Pb and Zn. In another particular embodiment, the metal species is selected from one or more alloys of metals selected from Cd, Co, Cr, Cu, Fe, K, Li, Mo, Na, Ni, Pb, and Zn. In yet another particular embodiment, the metal species is selected from one or more oxides of metals selected from Cd, Co, Cr, Cu, Fe, K, Li, Mo, Na, Ni, Pb and Zn.

In certain embodiments of the supercapacitor, the total water content in the electrolyte is less than about 500 parts per million, for example, less than about 100 parts per million, for example, less than about 50 parts per million, for example, less than about 20 parts per million.

In certain embodiments of the supercapacitor, the housing includes a barrier disposed over a substantial portion of its interior surface. In particular embodiments, the barrier comprises at least one of Polytetrafluoroethylene (PTFE), perfluoroalkoxy resin (PFA), fluorinated ethylene propylene copolymer (FEP), ethylene-tetrafluoroethylene copolymer (ETFE). In a particular embodiment, the barrier comprises a ceramic material. The barrier may also include materials that exhibit corrosion resistance, desirable dielectric properties, and low electrochemical reactivity. In a particular embodiment of the barrier, the barrier comprises a plurality of material layers.

In certain embodiments of the supercapacitor, the housing comprises a multilayer material, for example, wherein the multilayer material comprises a first material coated onto a second material. In particular embodiments, the multi-layer material comprises at least one of steel, tantalum, and aluminum.

In certain embodiments of the ultracapacitor, the housing comprises at least one hemispherical seal.

In certain embodiments of the supercapacitor, the housing comprises at least one glass-to-metal seal, for example, wherein a pin of the glass-to-metal seal provides one of the contacts. In certain embodiments, the glass-to-metal seal comprises a feedthrough composed of one of the following materials: iron-nickel-cobalt alloys, nickel-iron alloys, tantalum, molybdenum, niobium, tungsten, and certain forms of stainless steel and titanium. In another particular embodiment, the glass-to-metal seal includes a body composed of at least one material selected from the group consisting of: nickel, molybdenum, chromium, cobalt, iron, copper, manganese, titanium, zirconium, aluminum, carbon, and tungsten, and alloys thereof.

In certain embodiments of the ultracapacitor, the energy storage cell comprises a separator to provide electrical isolation between the positive electrode and the negative electrode, for example, wherein the separator comprises a material selected from the group consisting of polyamide, Polytetrafluoroethylene (PTFE), Polyetheretherketone (PEEK), alumina (Al)₂O₃) Glass fibers, glass fiber reinforced plastic, or any combination thereof. In certain embodiments, the separator is substantially free of moisture. In another particular embodiment, the separator comprises a hydrophobic material.

In certain embodiments of the supercapacitor, the hermetic seal exhibits the following leak rates: not greater than about 5.0 x 10^-6atm-cubic centimeter/second; e.g., no greater than about 5.0 x 10^-7atm-cubic centimeter/second; e.g., no greater than about 5.0 x 10^-8atm-cubic centimeter/second; e.g., no greater than about 5.0 x 10^-9atm-cubic centimeter/second; e.g., no greater than about 5.0 x 10^-10atm-cubic centimeter/second.

In certain embodiments of the supercapacitor, at least one contact is configured to mate with another contact of another supercapacitor.

In certain embodiments of the supercapacitor, the storage cell comprises a wrapper disposed over an exterior thereof, for example, wherein the wrapper comprises one of PTFE and polyimide.

In certain embodiments of the supercapacitor, the volumetric leakage current is less than about 10 amps/liter over a temperature range.

In certain embodiments of the supercapacitor, the volumetric leakage current is less than about 10 amps/liter within a particular voltage range between about 0 volts to about 4 volts, for example, between about 0 volts to about 3 volts, for example, between about 0 volts to about 2 volts, for example, between about 0 volts to about 1 volt. In certain embodiments of the ultracapacitor, the moisture level within the housing is less than about 1000 parts per million (ppm), for example, less than about 500 parts per million (ppm), for example, less than about 350 parts per million (ppm).

In certain embodiments of the supercapacitor, the moisture content in the electrode of the supercapacitor is less than about 1000ppm, for example, less than about 500ppm, for example, less than about 350 parts per million (ppm).

In certain embodiments of the supercapacitor, the moisture content in the separator of the supercapacitor is less than about 1000ppm, for example, less than about 500ppm, for example, less than about 160 parts per million (ppm).

In certain embodiments of the supercapacitor, the chloride ion content is less than about 300ppm for one of the components selected from the group consisting of the electrode, the electrolyte, and the separator.

In certain embodiments of the supercapacitor, the volumetric leakage current (mA/cubic centimeter) of the supercapacitor is less than about 10 mA/cubic centimeter while maintaining a substantially constant temperature, for example, in particular embodiments, less than about 1 mA/cubic centimeter while maintaining a substantially constant temperature.

In certain embodiments of the supercapacitor, the volumetric leakage current of the supercapacitor is greater than about 0.0001 mA/cc while maintaining a substantially constant temperature.

In certain embodiments of the supercapacitor, the volumetric capacitance of the supercapacitor is between about 6F/cc and about ImF/cc; between about 10F/cc and about 5F/cc; or between about 50F/cc and about 8F/cc.

In certain embodiments of the supercapacitor, the supercapacitor has a volumetric ESR between about 20 and 200 milliohm-cc, between about 150 and 2 ohm-cc, between about 1.5 and 200 ohm-cc, or between about 150 and 2000 ohm-cc.

In certain embodiments of the supercapacitor, the supercapacitor exhibits a capacitance drop of less than about 90% while maintaining a substantially constant voltage and operating temperature. In particular embodiments, the supercapacitor exhibits a capacitance drop of less than about 90% when held at a substantially constant voltage and operating temperature for at least 1 hour (e.g., at least 10 hours; e.g., at least 50 hours; e.g., at least 100 hours; e.g., at least 200 hours; e.g., at least 300 hours; e.g., at least 400 hours; e.g., at least 500 hours; e.g., at least 1000 hours).

In certain embodiments of the supercapacitor, the supercapacitor exhibits an ESR increase of less than about 1000% when held at a substantially constant voltage and operating temperature for at least 1 hour, e.g., at least 10 hours; for example, at least 50 hours; for example, at least 100 hours; for example, at least 200 hours; for example, at least 300 hours; for example, at least 400 hours; for example, at least 500 hours; for example, at least 1000 hours.

For example, as shown in FIG. 1, an exemplary embodiment of a capacitor is shown. In this case, the capacitor is a "supercapacitor 10". Exemplary supercapacitor 10 is an Electric Double Layer Capacitor (EDLC). The supercapacitor 10 may be implemented in several different form factors (i.e. exhibit a certain appearance). Examples of potentially useful form factors include cylindrical cells, wheel or ring cells, flat prismatic cells or stacks of flat prismatic cells including box cells, and flat prismatic cells adapted to accommodate a particular geometry (e.g., curved space). A cylindrical form factor may be most useful in conjunction with a cylindrical system or a system installed in a cylindrical form factor or having a cylindrical cavity. A wheel or ring unit form factor may be most useful in conjunction with a ring system or a system mounted in a ring form factor or having a ring cavity. The flat prismatic cell form factor may be most useful in connection with rectangular systems or systems mounted in a rectangular form factor or having rectangular cavities.

Although generally disclosed herein in the shape of a "jelly roll" application (i.e., the storage unit 12 is configured as a cylindrical shell 7), the rolled storage unit 23 may take any desired shape. For example, with respect to rolling up the storage unit 12, folding of the storage unit 12 may be performed to provide a rolled storage unit 23. Other types of assemblies may be used. As an example, the storage cells 12 may be flat cells, referred to as coin-type, pouch-type, or prism-type cells. Thus, rolling is only one option for an assembly of rolled storage units 23. Thus, although discussed herein with respect to "rolled storage units 23," this is not a limitation. The term "rolled storage unit 23" may be considered to generally include storage units 12 packaged or wrapped in any suitable form that is well suited for a given design of the shell 7.

Various shapes of supercapacitors 10 may be connected together. The various shapes may be connected using known techniques such as solder contact together, by using at least one mechanical connector, by arranging contacts that are in electrical contact with each other, and the like. The plurality of supercapacitors 10 may be electrically connected in at least one of a parallel and a series configuration.

For the purposes of the present invention, the volume of the supercapacitor 10 may be from about 0.05 ml to 7.5 liters.

There may be a variety of environments in which the ultracapacitor 10 is particularly useful. For example, in automotive applications, an ambient temperature of 105 degrees celsius (where the actual life of the capacitor is about 1 to 20 years) can be achieved. In some downhole applications, such as geothermal drilling, ambient temperatures of 300 degrees celsius or higher may be reached (where the actual life of the capacitor is about 1 hour to 10000 hours).

The components of the inventive supercapacitor will now be discussed in turn.

A.Advanced electrolyte system of the invention

The advanced electrolyte system of the present invention provides the electrolyte composition of the supercapacitor of the present invention and is labeled as "electrolyte 6" in fig. 1. The electrolyte 6 fills the void space in and between the electrode 3 and the separator 5. In general, the advanced electrolyte systems of the present invention include unique electrolytes, purification-enhanced electrolytes, or combinations thereof, wherein the electrolyte 6 is a substance (e.g., composed of one or more salts or ionic liquids) that dissociates into charged ions (e.g., positively charged cations and negatively charged anions) and may include a solvent. In the advanced electrolyte systems of the present invention, such electrolyte compositions are selected based on the enhancement of certain performance and durability characteristics, and may be combined with one or more solvents that dissolve the above to produce compositions with novel and useful electrochemical stability and performance.

The advanced electrolyte systems of the present invention provide unique and distinct advantages over existing energy storage devices (e.g., energy storage devices comprising electrolytes not disclosed herein, or energy storage devices comprising electrolytes of insufficient purity) for the supercapacitors of the present invention. These advantages include improvements in both performance and durability, such as one or more of the following: the total resistance is reduced; an increase in long-term stability of the resistance (e.g., a decrease in the resistance of the material at a given temperature over time); the total capacitance increases; increased long-term stability of the capacitance (e.g., a decrease in capacitance of the capacitor over time at a given temperature); the energy density is increased (e.g., by providing a higher voltage and/or by creating a higher capacitance); improved voltage stability, reduced vapor pressure, broader performance over the temperature range of the individual capacitor (e.g., no significant decrease in capacitance and/or no significant increase in ESR when switching between two temperatures, e.g., no greater than 90% decrease in capacitance and/or greater than 1000% increase in ESR when switching from about +30 ℃ to about-40 ℃), improved temperature durability of the individual capacitor (e.g., less than 50% decrease in capacitance after a given time at a given temperature and/or less than 100% increase in ESR after a given time at a given temperature, and/or less than 10A/L of leakage current after a given time at a given temperature, e.g., less than 40% decrease in capacitance and/or less than 75% increase in ESR, and/or less than 5A/L of leakage current; e.g., less than 30% decrease in capacitance and/or less than 50% increase in ESR), and/or leakage currents below 1A/L), ease of manufacture is improved (e.g., by having a reduced vapor pressure, resulting in better yield and/or a more efficient method of filling capacitors with electrolyte); and cost-effective improvements (e.g., by filling the void spaces with a less expensive material compared to other materials). For clarity, the performance characteristics relate to the following properties: these properties relate to the utility of the device in a given application, which is suitable for comparison with materials used in a similar given application; while durability relates to properties related to the ability to maintain the above properties over time. The above examples of performance and durability should be used to provide background support for what is considered herein to be "significant changes in performance or durability".

For clarity, and in general, reference to "electrolyte 6" as contained in the energy storage device of the present invention as used herein refers to the advanced electrolyte system of the present invention.

The properties of the AES or electrolyte 6 may be the result of an improvement selected from: increased capacitance, reduced Equivalent Series Resistance (ESR), high thermal stability, low glass transition temperature (Tg), improved viscosity, specific rheological (rheopectic) or thixotropic properties (e.g., temperature-dependent properties), as well as high conductivity and good electrical performance over a wide temperature range. For example, the electrolyte 6 may have a high fluidity or, on the contrary, be substantially solid, so that the isolation of the electrodes 3 is ensured.

The advanced electrolyte system of the present invention comprises: the novel electrolytes described herein for use in high temperature supercapacitors; highly purified electrolytes for use in high temperature supercapacitors; and an enhanced electrolyte combination suitable for use at temperatures from-40 degrees celsius to 210 degrees celsius without a significant reduction in performance or durability at all temperatures.

While the disclosure presented herein should focus on the application of the advanced electrolyte systems described herein to supercapacitors, these advanced electrolyte systems may be applied to any energy storage device.

i. Novel Electrolyte Entity (NEE)

In one embodiment, the Advanced Electrolyte System (AES) of the invention includes certain novel electrolytes for use in high temperature supercapacitors. In this regard, maintaining purity and low moisture has been found to be related to the grade of performance of the energy storage 10; also, the use of electrolytes comprising hydrophobic materials, as well as electrolytes exhibiting higher purity and lower moisture content, have been found to be advantageous for obtaining improved performance. These electrolytes exhibit good performance characteristics over a temperature range of about 80 degrees celsius to about 210 degrees celsius, for example, at about 80 degrees celsius to about 200 degrees celsius; for example, about 80 degrees celsius to about 190 degrees celsius; for example, about 80 degrees celsius to about 180 degrees celsius; for example, about 80 degrees celsius to about 170 degrees celsius; for example, about 80 degrees celsius to about 160 degrees celsius; for example, from about 80 degrees celsius to about 150 degrees celsius, for example, from about 85 degrees celsius to about 145 degrees celsius; for example, about 90 degrees celsius to about 140 degrees celsius; for example, about 95 degrees celsius to about 135 degrees celsius; for example, about 100 degrees celsius to about 130 degrees celsius; for example, about 105 degrees celsius to about 125 degrees celsius; for example, about 110 degrees celsius to about 120 degrees celsius.

Thus, novel electrolyte entities that can be used as Advanced Electrolyte Systems (AES) include materials comprising cations (e.g., the cations shown in fig. 8 and described herein) and anions or combinations of such materials. In some embodiments, the above-mentioned species include nitrogen-containing cations, oxygen-containing cations, phosphorus-containing cations, and/or sulfur-containing cations, including heteroaryl cations and heterocyclyl cations. In one set of embodiments, an Advanced Electrolyte System (AES) comprises a composition comprising an ionic liquid selected from the group consisting of ammonium, imidazole, and mixtures thereof

Azole

Piperidine derivatives

Pyrazine esters

Pyrazoles

Pyridazine

Pyridine compound

Pyrimidines

Sulfonium and thiazoles

Triazole compounds

Guanidine (guanidine)

Isoquinoline derivatives

Benzotriazole compounds

And cations of the viologen-type cations, any of which may be substituted with a substituent as described herein. In one embodiment, the novel electrolyte entity for use in the Advanced Electrolyte System (AES) of the invention comprises any combination of the cations shown in figure 8 and an anion selected from tetrafluoroborate, bis (trifluoromethylsulfonyl) imide, tetracyanoborate and trifluoromethanesulfonate, the cations shown in figure 8 being selected from

Piperidine derivatives

And ammonium, where each branched radical R_x(e.g., R)₁、R₂、R₃...R_x) Can be selected from alkyl, heteroalkyl, alkenyl, heteroalkenyl, alkynyl, heteroalkynyl, halogen, amino, nitro, cyano, hydroxyl, sulfate, sulfonate, and carbonyl, any of which is optionally substitutedAnd wherein at least two Rx are not H (i.e., such that the selection and orientation of the R groups results in the cationic species shown in fig. 8).

For example, given the combination of cations and anions described above, in particular embodiments, AES may be selected from trihexyltetradecyl

Bis (trifluoromethylsulfonyl) imide, 1-butyl-1-methylpiperidine

Bis (trifluoromethylsulfonyl) imide and butyltrimethylammonium bis (trifluoromethylsulfonyl) imide. Data supporting enhanced performance characteristics over a range of temperatures as evidenced by capacitance and ESR measurements over time are provided in fig. 44A and 44B, 45A and 45B, and 46A and 46B, which demonstrate high temperature utility and long term durability.

In certain embodiments, AES is trihexyltetradecyl

Bis (trifluoromethylsulfonyl) imide.

In certain embodiments, the AES is 1-butyl-1-methylpiperidine

Bis (trifluoromethylsulfonyl) imide.

In certain embodiments, the AES is butyltrimethylammonium bis (trifluoromethylsulfonyl) imide.

In another embodiment, the novel electrolyte entity useful in the Advanced Electrolyte System (AES) of the present invention comprises any combination of the cations shown in figure 8 selected from imidazole, and anions selected from tetrafluoroborate, bis (trifluoromethylsulfonyl) imide, tetracyanoborate and trifluoromethanesulfonate, and the cations shown in figure 8 are selected from imidazolium

And pyrrolidine

Wherein each branched group R_x(e.g., R)₁、R₂、R₃...R_x) May be selected from the group of alkyl, heteroalkyl, alkenyl, heteroalkenyl, alkynyl, heteroalkynyl, halogen, amino, nitro, cyano, hydroxy, sulfate, sulfonate, and carbonyl, any of which is optionally substituted, and wherein at least two R are optionally substituted_xIs not H (i.e., such that the selection and orientation of the R groups results in the cationic species shown in fig. 8). In a particular embodiment, two R's which are not H_xIs an alkyl group. Furthermore, the cations exhibit high thermal stability as well as high conductivity and exhibit good electrochemical performance over a wide temperature range.

For example, given the above combinations of cations and anions, in particular embodiments, AES may be selected from 1-butyl-3-methylimidazole

A tetrafluoroborate salt; 1-butyl-3-methylimidazole

Bis (trifluoromethylsulfonyl) imide, 1-ethyl-3-methylimidazole

A tetrafluoroborate salt; 1-ethyl-3-methylimidazole

A tetracyanoborate; 1-hexyl-3-methylimidazole

A tetracyanoborate; 1-butyl-1-methylpyrrolidine

Bis (trifluoromethylsulfonyl) imide; 1-butyl-1-methylpyrrolidine

Tris (pentafluoroethyl) trifluorophosphate; 1-butyl-1-methylpyrrolidine

Tetracyanoborate and 1-butyl-3-methylimidazole

A triflate salt.

In one embodiment, AES is 1-butyl-3-methylimidazole

A tetrafluoroborate salt.

In one embodiment, AES is 1-butyl-3-methylimidazole

Bis (trifluoromethylsulfonyl) imide.

In one embodiment, AES is 1-ethyl-3-methylimidazole

A tetrafluoroborate salt.

In one embodiment, AES is 1-ethyl-3-methylimidazole

Tetracyanoborate.

In one embodiment, AES is 1-hexyl-3-methylimidazole

Tetracyanoborate.

In one embodiment, AES is 1-butyl-1-methylpyrrolidine

Bis (trifluoromethylsulfonyl) imide.

In one embodiment, AES is 1-butyl-1-methylRadical pyrrolidine

Tris (pentafluoroethyl) trifluorophosphate.

In one embodiment, AES is 1-butyl-1-methylpyrrolidine

Tetracyanoborate.

In one embodiment, AES is 1-butyl-3-methylimidazole

A triflate salt.

In another particular embodiment, two R's which are not H_xOne is an alkyl group, e.g., methyl, and the other is an alkyl group substituted with an alkoxy group. Further, it has been found that cations having an N, O-acetal skeleton structure of the formula (1) in the molecule have high conductivity, and are included in these cations and have pyrrolidine

The conductivity and solubility of the framework and the ammonium cation of the N, O-acetal group in organic solvents are particularly high and support relatively high voltages. Thus, in one embodiment, an advanced electrolyte system includes a salt of the formula:

wherein R is₁And R₂Which may be the same or different, are all alkyl groups, and X-is an anion. In some embodiments, R₁Is a straight-chain or branched alkyl radical having from 1 to 4 carbon atoms, R₂Is methyl or ethyl, and X^-Is a cyano borate containing anion 11. In particular embodiments, X^-Comprises [ B (CN)]₄And R is₂Is one of methyl and ethyl. In another particular embodiment, R₁And R₂Are all methyl. Additionally, in one embodiment, the cyanoboronic anion 11, X, suitable for the advanced electrolyte systems of the present invention^-Comprising [ B (CN)4]^-Or [ BF ]_n(CN)4-n]^-Wherein n is 0, 1, 2 or 3.

Examples of cations of AES of the invention comprising the novel electrolyte entity of formula (1) and consisting of the quaternary ammonium cation shown in formula (I) and the cyanoboronic anion are selected from N-methyl-N-methoxymethylpyrrolidine

(N-methoxymethyl-N-methylpyrrolidine

) N-ethyl-N-methoxymethylpyrrolidine

N-methoxymethyl-N-N-propylpyrrolidine

N-methoxymethyl-N-isopropylpyrrolidine

N-N-butyl-N-methoxymethylpyrrolidine

N-isobutyl-N-methoxymethylpyrrolidine

N-tert-butyl-N-methoxymethylpyrrolidine

N-ethoxymethyl-N-methylpyrrolidine

N-ethyl-N-ethoxymethylpyrrolidine

(N-ethoxymethyl-N-ethylpyrrolidine)

) N-ethoxymethyl-N-N-propylpyrrolidine

N-ethoxymethyl-N-isopropylpyrrolidine

N-N-butyl-N-ethoxymethylpyrrolidine

N-isobutyl-N-ethoxymethylpyrrolidine

And N-tert-butyl-N-ethoxymethylpyrrolidine

Other examples include N-methyl-N-methoxymethylpyrrolidine

(N-methoxymethyl-N-methylpyrrolidine

) N-ethyl-N-methoxymethylpyrrolidine

And N-ethoxymethyl-N-methylpyrrolidine

Further examples of cations of formula (1) in combination with further anions may be selected from N-methyl-N-methoxymethylpyrrolidine

Tetracyanoboronate (N-methoxymethyl-N-methylpyrrolidine)

Tetracyanoborate), N-ethyl-N-methoxymethylpyrrolidine

Tetracyanoborate, N-ethoxymethyl-N-methylpyrrolidine

Tetracyanoborate, N-methyl-N-methoxymethylpyrrolidine

Bis (trifluoromethanesulfonyl) imide, (N-methoxymethyl-N-methylpyrrolidine)

Bis (trifluoromethanesulfonyl) imide), N-ethyl-N-methoxymethylpyrrolidine

Bis (trifluoromethanesulfonyl) imide, N-ethoxymethyl-N-methylpyrrolidine

Bis (trifluoromethanesulfonyl) imide, N-methyl-N-methoxymethylpyrrolidine

Triflate (N-methoxymethyl-N-methyltrifluoromethane sulfonate).

In the case of use as an electrolyte, a quaternary ammonium salt may be used in admixture with a suitable organic solvent. Useful solvents include cyclic carbonates, chain carbonates, phosphate esters, cyclic ethers, chain ethers, lactone compounds, chain esters, nitrile compounds, amide compounds, and sulfone compounds. Examples of such compounds are listed below, but the solvent used is not limited to these compounds.

Examples of the cyclic carbonate are ethylene carbonate, propylene carbonate, butylene carbonate, and the like, and among them, propylene carbonate is preferable.

Examples of the chain carbonate are dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate and the like, and among them, dimethyl carbonate and ethyl methyl carbonate are preferable.

Examples of phosphate esters are trimethyl phosphate, triethyl phosphate, ethyl dimethyl phosphate, diethyl methyl phosphate and the like. Examples of cyclic ethers are tetrahydrofuran, 2-methyltetrahydrofuran, and the like. Examples of the chain ether are ethylene glycol dimethyl ether and the like. Examples of the lactone compound are γ -butyrolactone and the like. Examples of the chain ester are methyl propionate, methyl acetate, ethyl acetate, methyl formate and the like. Examples of the nitrile compound are acetonitrile and the like. Examples of the amide compound are dimethylformamide and the like. Examples of sulfone compounds are sulfolane, methylsulfolane, and the like. In some embodiments, cyclic carbonates, chain carbonates, nitrile compounds, and sulfone compounds are particularly desirable.

These solvents may be used alone, or at least two solvents may be used in the form of a blend. Examples of preferred organic solvent mixtures are: mixtures of cyclic carbonates and chain carbonates, such as mixtures of ethylene carbonate and dimethyl carbonate, mixtures of ethylene carbonate and ethyl methyl carbonate, mixtures of ethylene carbonate and diethyl carbonate, mixtures of propylene carbonate and dimethyl carbonate, mixtures of propylene carbonate and ethyl methyl carbonate and mixtures of propylene carbonate and diethyl carbonate; a mixture of chain carbonates such as a mixture of dimethyl carbonate and ethyl methyl carbonate; and mixtures of sulfolane compounds such as sulfolane and methyl sulfolane. More preferred are mixtures of ethylene carbonate and ethyl methyl carbonate, mixtures of propylene carbonate and ethyl methyl carbonate and mixtures of dimethyl carbonate and ethyl methyl carbonate.

In some embodiments, where the quaternary ammonium salts of the present invention are used as an electrolyte, the electrolyte concentration is at least 0.1M, in some cases at least 0.5M and may be at least 1M. If the concentration is less than 0.1M, low conductivity will result, resulting in an electrochemical device with impaired performance. In the case where the electrolyte is a liquid salt at room temperature, the upper limit concentration is the separation concentration. In the case of a solution that does not separate, the limiting concentration is 100%. In the case of salts that are solid at room temperature, the limiting concentration is the concentration at which the solution is saturated with salt.

In certain embodiments, the Advanced Electrolyte System (AES) may be blended with electrolytes other than those disclosed herein, so long as such combination does not significantly affect the advantages achieved using the advanced electrolyte system, e.g., changing the performance or durability characteristics by more than 10%. Examples of electrolytes that may be suitable for blending with AES are alkali metal salts, quaternary ammonium salts, quaternary phosphonium salts

Salts and the like. These electrolytes may be used alone, or at least two of these electrolytes may be used in combination, when blended with the AES disclosed herein. Alkali metal salts that may be used include lithium, sodium and potassium salts. Examples of such lithium salts are lithium hexafluorophosphate, lithium fluoroborate, lithium perchlorate, lithium trifluoromethanesulfonate, lithium sulfonimide, lithium methylsulfonyl and the like, however this is not limitative. Examples of sodium salts that can be used are sodium hexafluorophosphate, sodium fluoroborate, sodium perchlorate, sodium trifluoromethanesulfonate, sodium sulfonimide, sodium methylsulfonate and the like. Examples of potassium salts that can be used are potassium hexafluorophosphate, potassium fluoroborate, potassium perchlorate, potassium trifluoromethanesulfonate, potassium sulfonimide, potassium methylsulfonate and the like, however these are not limitative.

The quaternary ammonium salts that may be used in combination as described above (i.e., without significantly affecting the advantages achieved using advanced electrolyte systems) include tetraalkylammonium salts, imidazoles

Salt, pyrazole

Salt, pyridine

Salt, triazole

Salt, pyridazine

Salts, and the like, which are not limiting. Examples of tetraalkylammonium salts which can be used are tetraethylammonium tetracyanoborate, tetramethylammonium tetracyanoborate, tetrapropylammonium tetracyanoborate, tetrabutylammonium tetracyanoborate, triethylmethylammonium tetracyanoborate, trimethylethylammonium tetracyanoborate, dimethyldiethylammonium tetracyanoborate, trimethylpropylammonium tetracyanoborate, trimethylbutylammonium tetracyanoborate, dimethylethylpropylammonium tetracyanoborate, methylethylpropylbutylammonium tetracyanoborate, N-dimethylpyrrolidine

Tetracyanoborate, N-ethyl-N-methylpyrrolidine

Tetracyanoborate, N-methyl-N-propylpyrrolidine

Tetracyanoborate, N-ethyl-N-propylpyrrolidine

Tetracyanoborate, N-dimethylpiperidine

Tetracyanoborate, N-methyl-N-ethylpiperidine

Tetracyanoborate, N-methyl-N-propylpiperidine

Tetracyanoborate, N-ethyl-N-propylpiperidine

Tetracyanoborate, N-dimethylmorpholine

Tetracyanoborate, N-methyl-N-ethylmorpholine

Tetracyanoborate, N-methyl-N-propylmorpholine

Tetracyanoborate, N-ethyl-N-propylmorpholine

Tetracyanoborate, and the like, although these examples are not limiting.

The above-described imidazoles may be used in combination (i.e., without significantly affecting the advantages achieved using advanced electrolyte systems)

Examples of salts include 1, 3-dimethylimidazole

Tetracyanoborate, 1-ethyl-3-methylimidazole

Tetracyanoborate, 1, 3-diethylimidazole

Tetracyanoborate, 1, 2-dimethyl-3-ethylimidazole

Tetracyanoborate and 1, 2-dimethyl-3-propylimidazole

Tetracyanoborate, but is not limited thereto.Pyrazoles

An example of a salt is 1, 2-dimethylpyrazole

Tetracyanoborate, 1-methyl-2-ethylpyrazole

Tetracyanoborate, 1-propyl-2-methylpyrazole

Tetracyanoborate and 1-methyl-2-butylpyrazole

Tetracyanoborate, but is not limited thereto. Pyridine compound

An example of a salt is N-methylpyridine

Tetracyanoborate, N-ethylpyridine

Tetracyanoborate, N-propylpyridine

Tetracyanoborate and N-butylpyridine

Tetracyanoborate, but is not limited thereto. Triazole compounds

An example of a salt is 1-methyltriazole

Tetracyanoborate, 1-ethyltrisAzole

Tetracyanoborate, 1-propyltriazole

Tetracyanoborate and 1-butyltriazole

Tetracyanoborate, but is not limited thereto. Pyridazine

An example of a salt is 1-methylpyridazine

Tetracyanoborate, 1-ethylpyridazine

Tetracyanoborate, 1-propylpyridazine

Tetracyanoborate and 1-butylpyridazine

Tetracyanoborate, but is not limited thereto. Season

An example of a salt is tetraethyl

Tetracyanoborate, tetramethyl

Tetracyanoborate, tetrapropyl

Tetracyanoborate, tetrabutyl

Tetracyanoborate, triethylmethyl

Tetracyanoborate, trimethylethyl

Tetracyanoborate, dimethyldiethyl

Tetracyanoborate, trimethylpropyl

Tetracyanoborate, trimethylbutyl

Tetracyanoborate, Dimethylethylpropyl

Tetracyanoborate, methylethylpropylbutyl

Tetracyanoborate, but is not limited thereto.

In certain embodiments, the novel electrolytes selected herein for use in advanced electrolyte systems may also be purified. Such purification can be performed using techniques well known in the art or provided herein. This purification may further improve the properties of the novel electrolyte entities described herein.

Highly purified electrolyte

In one embodiment, the advanced electrolyte systems of the present invention include certain highly purified electrolytes for use in high temperature supercapacitors. In certain embodiments, the highly purified electrolytes comprising the AES of the invention are those described below and those novel electrolytes described above purified by the purification methods described herein. The purification methods provided herein result in impurity levels that can provide advanced electrolyte systems with enhanced performance for use in high temperature applications (e.g., high temperature supercapacitors), for example, in a temperature range of about 80 degrees celsius to about 210 degrees celsius, for example, about 80 degrees celsius to about 200 degrees celsius; for example, about 80 degrees celsius to about 190 degrees celsius; for example, about 80 degrees celsius to about 180 degrees celsius; for example, about 80 degrees celsius to about 170 degrees celsius; for example, about 80 degrees celsius to about 160 degrees celsius; for example, about 80 degrees celsius to about 150 degrees celsius; for example, about 85 degrees Celsius to about 145 degrees Celsius; for example, about 90 degrees celsius to about 140 degrees celsius; for example, about 95 degrees celsius to about 135 degrees celsius; for example, about 100 degrees celsius to about 130 degrees celsius; for example, about 105 degrees celsius to about 125 degrees celsius; for example, about 110 degrees celsius to about 120 degrees celsius.

Obtaining improved properties of the ultracapacitor 10 results in a need for better electrolyte systems than currently available electrolyte systems. For example, it has been found that increasing the operating temperature range can be achieved by significantly reducing/removing impurities from certain forms of known electrolytes. Impurities of particular interest include water, halides (chloride, bromide, fluoride and iodide), free amines (ammonia), sulfate and metal cations (Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Sr, Ti, Zn). The highly purified electrolyte product thus purified provides an electrolyte that is unexpectedly far superior to unpurified electrolytes and, therefore, is an advanced electrolyte system of the present invention.

In particular embodiments, the present invention provides mixtures of purified cations 9 and anions 11 and, in some cases, solvents that may be used as AES of the invention comprising less than about 5000 parts per million (ppm) chloride ions; less than about 1000ppm of fluoride ions; and/or less than about 1000ppm water (e.g., less than about 2000ppm chloride ion; less than about 200ppm fluoride ion; and/or less than about 200ppm water, e.g., less than about 1000ppm chloride ion; less than about 100ppm fluoride ion; and/or less than about 100ppm water, e.g., less than about 500ppm chloride ion, less than about 50ppm fluoride ion; and/or less than about 50ppm water, e.g., less than about 780 parts per million chloride ion; less than about 11 parts per million fluoride ion; and less than about 20 parts per million water.)

Generally, impurities in the electrolyte being purified are removed using the purification methods described herein. For example, in some embodiments, the total concentration of halide ions (chloride, bromide, fluoride and iodide) may be reduced to less than about 1000 ppm. The total concentration of metal species (e.g., Cd, Co, Cr, Cu, Fe, K, Li, Mo, Na, Ni, Pb, Zn, including at least one of alloys and oxides thereof) may be reduced to less than about 1000 ppm. In addition, impurities from the solvents and precursors used in the synthesis process can be reduced to less than about 1000ppm, and can include, for example, ethyl bromide, ethyl chloride, 1-bromobutane, 1-chlorobutane, 1-methylimidazole, ethyl acetate, methylene chloride, and the like.

In some embodiments, the impurity content of the supercapacitor 10 is measured using ion selective electrodes and Karl Fischer (Karl Fischer) titration that have been applied to the electrolyte 6 of the supercapacitor 10. In certain embodiments, the total halide content of the ultracapacitor 10 according to the teachings herein is found to be less than about 200ppm halide (Cl)^-And F^-) The water content is less than about 100 ppm.

Impurities can be measured using various techniques such as Atomic Absorption Spectroscopy (AAS), Inductively Coupled Plasma Mass Spectrometry (ICPMS), or simplified solubilization and electrochemical sensing of trace heavy metal oxide particles. AAS is a spectroscopic analysis method for qualitatively and quantitatively determining chemical elements using absorption of light radiation (light) through gaseous free atoms. This technique is used to determine the concentration of a particular element (analyte) in a sample to be analyzed. AAS can be used to determine over 70 different elements in solution or directly in a solid sample. ICPMS is a mass spectrometry method that is highly sensitive and capable of measuring less than 10 of metals and several non-metals¹²A range of parts per billion (ppm) concentrations. The technique is based on inductive coupling as a method of generating ions (ionization)Combining the plasma with mass spectrometry as a method of separating and detecting ions. ICPMS is also able to monitor the isotopic morphology of selected ions.

Additional techniques may be used to analyze the impurities. Some of these techniques are particularly advantageous for analyzing impurities in solid samples. Ion Chromatography (IC) can be used to determine trace levels of halide impurities in the electrolyte 6 (e.g., ionic liquid). One advantage of ion chromatography is that the relevant halides can be measured by monochromatic spectral analysis. A Dionex AS9-HC column using an eluent comprising 20mM NaOH and 10% (v/v) acetonitrile is one example of an apparatus that can be used to quantify halides from ionic liquids. Another technique is X-ray fluorescence spectroscopy.

An X-ray fluorescence (XRF) instrument may be used to measure the halogen content in a solid sample. In this technique, a sample to be analyzed is placed in a sample cup, and then the sample cup is placed in an analyzer irradiated with X-rays of a specific wavelength. Any halogen atom in the sample absorbs a portion of the X-rays and then reflects radiation at a wavelength characteristic of a given halogen. A detector in the instrument then quantifies the amount of radiation that comes back from the halogen atoms and measures the radiation intensity. By knowing the exposed surface area, the concentration of halogen in the sample can be determined. Another technique for assessing impurities in a solid sample is the pyrolysis technique.

The adsorption of impurities can be effectively measured by using a pyrolysis and microcoulometer (microcoulometer). The microcurrent meter is capable of testing the total chlorine content of almost any type of material. As an example, a small amount of sample (less than 10 mg) is injected or placed into a quartz burner tube, where the temperature is from about 600 degrees celsius to about 1000 degrees celsius. Pure oxygen was passed through the quartz tube and any chlorine-containing components were completely combusted. The resulting combustion products are purged into the titration unit, wherein chloride ions are trapped in the electrolyte solution. The electrolyte solution contains silver ions which immediately bind to any chloride ions and are released from the solution as insoluble silver chloride (drop out). The silver electrode in the titration unit electrically replaces the used up silver ions until the concentration of silver ions returns to the concentration before the start of the titration. By tracking the amount of current required to produce the desired amount of silver, the instrument is able to determine how much chlorine is present in the initial sample. The total amount of chlorine present divided by the weight of the sample gives the concentration of chlorine actually in the sample. Other techniques for assessing impurities may be used.

For example, surface features and water content in the electrode 3 may be detected by infrared spectroscopy techniques. At about 1130cm^-1、1560cm^-1、3250cm^-1And 2300cm^-1The four main absorption bands at (a) correspond to vC ═ O, vC ═ C, vO-H in the aryl group, and vC-N, respectively. By measuring the intensity and peak position, surface impurities in the electrode 3 can be quantitatively determined.

Another technique for determining impurities in the electrolyte 6 and the supercapacitor 10 is raman spectroscopy. The spectroscopic technique relies on inelastic or raman scattering of monochromatic light, typically from lasers in the visible, near infrared or near ultraviolet ranges. The laser interacts with molecular vibrations, phonons, or other excitations in the system, causing the energy of the laser photons to change up and down. Thus, this technique can be used to characterize atoms and molecules in the supercapacitor 10. Many variations of raman spectroscopy are employed and may prove useful in characterizing the contents of the supercapacitor 10.

Enhanced electrolyte combinations

In one embodiment, the advanced electrolyte systems of the present invention include certain enhanced electrolyte combinations suitable for use without a significant decrease in performance or durability at a temperature range of-40 degrees celsius to 210 degrees celsius; for example, -40 to 150 degrees celsius; for example, -30 to 150 degrees celsius; for example, -30 to 140 degrees celsius; for example, -20 to 140 degrees celsius; for example, -20 to 130 degrees celsius; for example, -10 to 130 degrees celsius; for example, -10 to 120 degrees celsius; for example, 0 to 120 degrees celsius; for example, 0 to 110 degrees celsius, e.g., 0 to 100 degrees celsius; for example, 0 to 90 degrees celsius; for example, 0 to 80 degrees celsius; for example, 0 to 70 degrees celsius.

In general, a higher degree of durability at a given temperature may be consistent with a higher degree of voltage stability at a lower temperature. Thus, the development of high temperature durable AES with enhanced electrolyte combinations will typically result in high voltage but lower temperature AES being developed at the same time, so that these enhanced electrolyte combinations described herein can also be used at higher voltages and therefore higher energy densities but lower temperatures.

In one embodiment, the present invention provides an enhanced electrolyte combination suitable for use in an energy storage unit (e.g., a supercapacitor), the enhanced electrolyte combination comprising a novel electrolyte mixture selected from the group consisting of: an ionic liquid mixed with the second ionic liquid, an ionic liquid mixed with the organic solvent, and an ionic liquid mixed with the second ionic liquid and the organic solvent.

Wherein each ionic liquid is selected from salts of any combination of the following cations and anions, wherein the cation is selected from: 1-butyl-3-methylimidazole

1-ethyl-3-methylimidazole

1-hexyl-3-methylimidazole

1-butyl-1-methylpiperidine

Butyltrimethylammonium, 1-butyl-1-methylpyrrolidine

Trihexyltetradecyl

And 1-butyl-3-methylimidazole

And the anion is selected from: tetrafluoroborate, bis (trifluoromethylsulfonyl) imide, tetracyanoborate and trifluoromethanesulfonate; and

wherein the organic solvent is selected from the group consisting of linear sulfones (e.g., ethyl isopropyl sulfone, ethyl isobutyl sulfone, ethyl methyl sulfone, methyl isopropyl sulfone, isopropyl isobutyl sulfone, isopropyl sec-butyl sulfone, butyl isobutyl sulfone, and dimethyl sulfone), linear carbonates (e.g., ethylene carbonate, propylene carbonate, and dimethyl carbonate), and acetonitrile.

For example, given the above combinations of cations and anions, each ionic liquid may be selected from: 1-butyl-3-methylimidazole

Tetrafluoroborate, 1-butyl-3-methylimidazole

Bis (trifluoromethylsulfonyl) imide, 1-ethyl-3-methylimidazole

Tetrafluoroborate, 1-ethyl-3-methylimidazole

Tetracyanoborate, 1-hexyl-3-methylimidazole

Tetracyanoborate, 1-butyl-1-methylpyrrolidine

Bis (trifluoromethylsulfonyl) imide, 1-butyl-1-methylpyrrolidine

Tris (pentafluoroethyl) trifluorophosphate, 1-butyl-1-methylpyrrolidine

TetracyanoborateTrihexyltetradecyl radical

Bis (trifluoromethylsulfonyl) imide, 1-butyl-1-methylpiperidine

Bis (trifluoromethylsulfonyl) imide, butyltrimethylammonium bis (trifluoromethylsulfonyl) imide, and 1-butyl-3-methylimidazole

A triflate salt.

In certain embodiments, the ionic liquid is 1-butyl-3-methylimidazole

A tetrafluoroborate salt.

In certain embodiments, the ionic liquid is 1-butyl-3-methylimidazole

Bis (trifluoromethylsulfonyl) imide.

In certain embodiments, the ionic liquid is 1-ethyl-3-methylimidazole

A tetrafluoroborate salt.

In certain embodiments, the ionic liquid is 1-ethyl-3-methylimidazole

Tetracyanoborate.

In certain embodiments, the ionic liquid is 1-hexyl-3-methylimidazole

Tetracyanoborate.

In certain embodiments, the ionic liquid is 1-butyl-1-methylpyrrolidine

Bis (trifluoromethylsulfonyl) imide.

In one embodiment, the ionic liquid is 1-butyl-1-methylpyrrolidine

Tris (pentafluoroethyl) trifluorophosphate.

In certain embodiments, the ionic liquid is 1-butyl-1-methylpyrrolidine

Tetracyanoborate.

In certain embodiments, the ionic liquid is trihexyltetradecyl

Bis (trifluoromethylsulfonyl) imide.

In certain embodiments, the ionic liquid is 1-butyl-1-methylpiperidine

Bis (trifluoromethylsulfonyl) imide.

In certain embodiments, the ionic liquid is butyltrimethylammonium bis (trifluoromethylsulfonyl) imide.

In certain embodiments, the ionic liquid is 1-butyl-3-methylimidazole

A triflate salt.

In certain embodiments, the organic solvent is selected from ethyl isopropyl sulfone, ethyl isobutyl sulfone, ethyl methyl sulfone, methyl isopropyl sulfone, isopropyl isobutyl sulfone, isopropyl sec-butyl sulfone, butyl isobutyl sulfone, or dimethyl sulfone, straight chain sulfone.

In certain embodiments, the organic solvent is selected from the group consisting of polypropylene carbonate, propylene carbonate, dimethyl carbonate, ethylene carbonate.

In certain embodiments, the organic solvent is acetonitrile.

In certain embodiments, the enhanced electrolyte composition is an ionic liquid with an organic solvent, wherein the organic solvent is from 55% to 90%, e.g., 37.5%, by volume of the composition.

In certain embodiments, the enhanced electrolyte composition is an ionic liquid having a second ionic liquid, wherein one ionic liquid is from 5% to 90%, for example, 60%, by volume of the composition.

The enhanced electrolyte combination of the present invention provides a wider temperature range performance for a single capacitor (e.g., no significant decrease in capacitance and/or no significant increase in ESR when transitioning between two temperatures, e.g., no greater than 90% decrease in capacitance and/or no greater than 1000% increase in ESR when transitioning from about +30 ℃ to about-40 ℃), and an increase in temperature endurance for a single capacitor (e.g., less than 50% decrease in capacitance after a given time at a given temperature and/or less than 100% increase in ESR after a given time at a given temperature, and/or less than 10A/L of leakage current after a given time at a given temperature; e.g., less than 40% decrease in capacitance and/or less than 75% increase in ESR, and/or less than 5A/L of leakage current; e.g., less than 30% decrease in capacitance and/or less than 50% increase in ESR), and/or a leakage current of less than 1A/L). Fig. 47A and 47B, fig. 48A and 48B, and fig. 49 show the behavior of ionic liquids from the above ionic liquids at 125 degrees celsius, 37.5% organic solvent-ionic liquid (same) v/v at 125 degrees celsius, and the same composition at-40 degrees celsius, respectively.

Without wishing to be bound by theory, the combination provides enhanced eutectic properties affecting the freezing point of advanced electrolyte systems to enable the supercapacitor to operate within performance and durability standards at temperatures as low as-40 degrees celsius.

As described above for the novel electrolytes of the present invention, in certain embodiments, the Advanced Electrolyte System (AES) may be blended with an electrolyte, so long as such combination does not significantly impact the advantages achieved using the advanced electrolyte system.

In certain embodiments, the enhanced electrolytes selected herein for advanced electrolyte systems may also be purified. Such purification can be performed using techniques well known in the art or provided herein.

B.Electrode for electrochemical cell

The EDLC includes at least one pair of electrodes 3 (wherein the electrodes 3 may be referred to as a negative electrode 3 and a positive electrode 3 for the purposes of reference herein only). When assembled into a supercapacitor 10, each electrode 3 presents an electrical double layer at the electrolyte interface. In some embodiments, a plurality of electrodes 3 is included (e.g., in some embodiments, at least two pairs of electrodes 3 are included). However, for purposes of discussion, only one pair of electrodes 3 is shown. As is customary herein, at least one of the electrodes 3 uses a carbon-based energy storage medium 1 (as discussed further herein) to provide energy storage. However, for purposes of discussion herein, it is generally assumed that each of the electrodes includes a carbon-based energy storage medium 1.

i current collector

Each of the electrodes 3 comprises a respective current collector 2 (also referred to as "charge collector"). In some embodiments, the electrodes 3 are separated by separators 5. In general, the separator 5 is a thin structural material (typically a sheet) used to separate the negative electrode 3 from the positive electrode 3. The separator 5 may also be used to separate pairs of electrodes 3. Note that in some embodiments, carbon-based energy storage medium 1 may not be included on one or both of electrodes 3. That is, in some embodiments, the respective electrode 3 may consist only of the current collector 2. The material used to provide the current collector 2 may be roughened, anodized, or the like to increase its surface area. In these embodiments, the individual current collectors 2 may serve as the electrodes 3. However, in this regard, the term "electrode 3" as used herein generally refers to the combination of the energy storage medium 1 and the current collector 2 (although this is not limiting for at least the foregoing reasons).

Energy storage media

In the exemplary supercapacitor 10, the energy storage medium 1 is formed of carbon nanotubes. The energy storage medium 1 may comprise other carbonaceous materials including, for example, activated carbon, carbon fiber, rayon, graphene, aerogel, carbon cloth, and various forms of carbon nanotubes. The activated carbon electrode can be manufactured, for example, by the following steps: performing a first activation treatment on a carbon material obtained by carbonization of a carbon compound to produce a carbon-based material; manufacturing a formed body by adding a binder to the carbon-based material; carbonizing the formed body; and finally manufacturing an activated carbon electrode by performing a second activation treatment on the carbonized formed body. Carbon fiber electrodes may be fabricated, for example, by preforming using paper or cloth of carbon fibers having a high surface area.

In an exemplary method for manufacturing carbon nanotubes, an apparatus for producing aligned carbon nanotube aggregates (aligned carbon-nanotube aggregates) includes an apparatus for synthesizing aligned carbon nanotube aggregates on a substrate having a catalyst on a surface thereof. The apparatus comprises: a forming unit that performs a forming step of making an environment around the catalyst a reducing gas environment and heating at least the catalyst or the reducing gas; a growth unit that performs a growth step of synthesizing aligned carbon nanotube aggregates by making an environment around the catalyst an environment of a raw material gas and by heating at least the catalyst or the raw material gas; and a transfer unit that transfers at least the substrate from the forming unit to the growth unit. Various other methods and apparatus may be used to provide aligned carbon nanotube aggregates.

In some embodiments, the materials used to form the energy storage medium 1 may include materials other than pure carbon (and forms of carbon that may be present or later invented). That is, various formulations of other materials may be included in the energy storage medium 1. More specifically, and as a non-limiting example, at least one binder material may be used in the energy storage medium 1, however, this is not a suggestion or requirement for the addition of other materials (e.g., binder materials). However, in general, the energy storage medium 1 is substantially formed of carbon, and thus may be referred to herein as a "carbonaceous material," a "carbonaceous layer," and other similar terms. In short, although formed primarily of carbon, the energy storage medium 1 may include any form of carbon (as well as any additives or impurities deemed appropriate or acceptable) to provide the desired functionality as the energy storage medium 1.

In one set of embodiments, the carbonaceous material comprises at least about 60% by mass elemental carbon, and in other embodiments at least about 75%, 85%, 90%, 95%, or 98% by mass elemental carbon.

The carbonaceous material may include carbon in a variety of forms, including carbon black, graphene, and the like. The carbonaceous material may comprise carbon particles (including nanoparticles, such as nanotubes, nanorods, graphene sheets in sheet form) and/or be formed as cones, rods, spheres (buckyballs), and the like.

Some embodiments of carbonaceous materials suitable for use in various formations of the energy storage medium 1 are provided herein as examples. These embodiments provide robust energy storage and are well suited for use in the electrode 3. It should be noted that these examples are illustrative and not limiting of the embodiments of the carbonaceous material suitable for use in the energy storage medium 1.

In certain embodiments, the porosity of the energy storage medium 1 of each electrode may be selected based on the size of each electrolyte to enhance the performance of the capacitor.

An exemplary method for configuring (compensating) the current collector 2 for the energy storage medium 1 to provide the electrode 3 is now provided. Referring now to fig. 2, substrate 14 is shown as a matrix of carbonaceous material in the form of carbon nanotube aggregates (CNTs). In the embodiment shown, the substrate 14 includes a base material 17 having a thin layer of catalyst 18 disposed thereon.

Generally, the substrate 14 is at least somewhat flexible (i.e., the substrate 14 is not fragile) and is made of components that can withstand the environment in which the energy storage medium 1 (e.g., CNTs) is deposited. For example, the substrate 14 may be subjected to a high temperature environment of between about 400 degrees Celsius and about 1100 degrees Celsius. A variety of materials may be used for substrate 14, as determined appropriate.

Reference is now made to fig. 3. Once the energy storage medium 1 (e.g., CNT) has been fabricated on the substrate 14, the current collector 2 can be disposed thereon. In some embodiments, current collector 2 is about 0.5 micrometers (μm) to about 25 micrometers (μm) thick. In some embodiments, current collector 2 is about 20 micrometers (μm) to about 40 micrometers (μm) thick. The current collector 2 may represent a thin layer, for example a layer applied by Chemical Vapor Deposition (CVD), sputtering, electron beam, thermal evaporation or by another suitable technique. In general, the current collector 2 is selected for its properties such as conductivity, electrochemical inertness and compatibility with the energy storage medium 1 (e.g., CNT). Some exemplary materials include aluminum, platinum, gold, tantalum, titanium, and may include other materials and various alloys.

The electrode element 15 is realized once the current collector 2 is arranged on the energy storage medium 1 (e.g. CNT). Each electrode element 15 may be used alone as an electrode 3, or may be coupled to at least one other electrode element 15 to provide an electrode 3.

Once the current collector 2 is manufactured according to the desired criteria, post-processing may be undertaken. Exemplary post-processing includes heating and cooling the energy storage medium 1 (e.g., CNTs) in a slightly oxidizing environment. After manufacture (and optional post-treatment), a transfer tool may be applied to the current collector 2. Reference may be made to fig. 4.

Fig. 4 shows the application of the transfer tool 13 to the current collector 2. In this embodiment, the transfer tool 13 is a thermal release tape (thermal release tape) used in the "dry" transfer method. Exemplary thermal release tapes are manufactured by Fremont (Fremont) of California and NITTO DENKO CORPORATION of Osaka (Osaka) of Japan. One suitable transfer tape is sold as REVALPHA. The release tape is characterized by an adhesive tape that is firmly adhered at room temperature and can be released by heating. The tape, as well as other suitable embodiments of the thermal release tape, will release at a predetermined temperature. Advantageously, the release tape does not leave chemically active residues on the electrode element 15.

In another process, known as a "wet" transfer process, a belt designed for chemical stripping may be used. Once applied, the tape is then removed by dipping the tape into a solvent. The solvent is designed to dissolve the binder.

In other embodiments, the transfer means 13 employs a "pneumatic" method, for example by applying suction to the current collector 2. Suction may be applied, for example, by a slightly larger sized blade (paddle) having a plurality of perforations for distributing suction. In another embodiment, the suction is applied by a roller having a plurality of perforations for distributing the suction. The suction-driven embodiment provides the advantage of being electrically controlled and economical because the consumable is not used as part of the transfer process. Other embodiments of the transfer tool 13 may be used.

Once the transfer tool 13 is temporarily coupled to the current collector 2, the electrode element 15 is gently removed from the substrate 14 (see fig. 4 and 5). The removal generally involves peeling the energy storage medium 1 (e.g., CNTs) from the substrate 14 starting from one edge of the substrate 14 and the energy storage medium 1 (e.g., CNTs).

The transfer tool 13 can then be separated from the electrode element 15 (see fig. 6). In some embodiments, the transfer tool 13 is used to mount the electrode element 15. For example, the electrode element 15 may be arranged on the separator 5 using the transfer tool 13. In general, the electrode element 15 is ready for use once removed from the substrate 14.

In the case where a large electrode 3 is desired, a plurality of electrode elements 15 may be matched. Reference may be made to fig. 7. As shown in fig. 7, the plurality of electrode elements 15 may be mated by, for example, coupling a coupling member 52 with each electrode element 15 of the plurality of electrode elements 15. The matched electrode element 15 provides an embodiment of the electrode 3.

In some embodiments, a coupling 22 is coupled to each electrode element 15 at the weldment 21. Each weld 21 may be provided as an ultrasonic weld 21. Ultrasonic welding techniques have been found to be particularly well suited to providing each weld element 21. That is, in general, aggregates of energy storage media 1 (e.g., CNTs) are incompatible with soldering, where only nominal current collectors such as disclosed herein are used. Thus, many techniques for connecting the electrode elements 15 are destructive and damage to the elements 15. However, in other embodiments, other forms of coupling are used and the coupling 22 is not a weldment 21.

Coupling 22 may be a foil, mesh, plurality of wires, or other form. Generally, coupling 22 is selected for characteristics such as conductivity and electrochemical inertness. In some embodiments, the coupling member 22 is made of the same material as that present in the current collector 2.

In some embodiments, coupling 22 is fabricated by removing an oxide layer thereon. The oxide may be removed, for example, by etching the coupling 22 prior to providing the weld 21. Etching may be accomplished, for example, with potassium hydroxide (KOH). The electrode 3 may be used in various embodiments of the supercapacitor 10. For example, the electrode 3 may be rolled up to form an energy storage of the "jelly roll" type.

C.Isolator

The separator 5 may be made of various materials. In some embodiments, the separator 5 is a non-woven glass. The separator 5 may also be made from fiberglass, ceramic, and a fluoropolymer such as Polytetrafluoroethylene (PTEE) commonly sold as teflon by DuPont Chemicals of Wilmington, DE. For example, using non-woven glass, the separator 5 may include primary fibers and binder fibers, each binder fiber having a fiber diameter smaller than that of each primary fiber and enabling the primary fibers to be bonded together.

For long life of the supercapacitor 10 and for ensuring performance at high temperatures, the separator 5 should have a reduced amount of impurities, and in particular a very limited amount of moisture contained therein. In particular, it has been found that a moisture limit of about 200ppm is desirable to reduce chemical reactions and extend the life of the supercapacitor 10, as well as to provide good performance in high temperature applications. Some embodiments of materials used in the separator 5 include polyamide, Polytetrafluoroethylene (PTFE), Polyetheretherketone (PEEK), alumina (Al)₂O₃) Glass fibers, and Glass Reinforced Plastics (GRPs).

In general, the material used for the separator 5 is selected according to moisture content, porosity, melting point, impurity content, resulting electrical properties, thickness, cost, availability, and the like. In some embodiments, the separator 5 is formed of a hydrophobic material.

Therefore, some method may be employed to ensure that excess moisture is removed from each separator 5. Vacuum drying methods and other techniques may be employed. The choice of materials for the separator 5 is provided in table 1. Some relevant performance data are provided in table 2.

TABLE 1

Isolator material

TABLE 2

Isolator performance data

In order to collect the data of table 2, two electrodes 3 based on carbonaceous materials are provided. The two electrodes 3 are disposed oppositely and face each other. Each separator 5 is arranged between the electrodes 3 to prevent short-circuiting. The three parts are then wetted with electrolyte 6 and pressed together. The resulting supercapacitor 10 is enclosed using two aluminum rods and a PTFE material as the outer structure.

The ESR first test and the ESR second test were performed one after another in the same configuration. The second test was run 5 minutes after the first test, leaving time for the electrolyte 6 to penetrate further into the part.

In certain embodiments, the supercapacitor 10 does not include the separator 5. For example, in particular embodiments, such as those in which the electrodes 3 are physically separated by the geometry of the structure, it is sufficient to have only the electrolyte 6 between the electrodes 3. More specifically, and as an example of physical isolation, one such supercapacitor 10 may include electrodes 3 disposed within a housing such that isolation is ensured on a continuous basis. One example of a bench-top (bench-top) would include a supercapacitor 10 disposed in a beaker (baker).

D.Memory cell

Once assembled, the electrodes 3 and the separator 5 provide a memory cell 12. Generally, the storage unit 12 is formed in one of a roll form or a prism form, and then is enclosed in the cylindrical or prism-shaped case 7. Once the electrolyte 6 has been contained, the housing 7 can be hermetically sealed. In various embodiments, the package is hermetically sealed by techniques utilizing lasers, ultrasound, and/or welding techniques. In addition to providing robust physical protection for the storage unit 12, the housing 7 is also configured with external contacts to provide electrical communication with the terminals 8 within the housing 7. Each terminal 8 in turn provides an electrical connection (electrical a cubic centimeter ess) to the energy stored in the energy storage medium 1, typically through an electrical lead coupled to the energy storage medium 1.

Generally, the ultracapacitors 10 disclosed herein are capable of providing a leakage rate of no greater than about 5.0 x 10^- ⁶an atm-cubic centimeter/second hermetic seal, and can exhibit no more than about 5.0 x 10^-10atm-cubic centimeter per second leak rate. It is also believed that the performance of a successful hermetic seal is judged by the user, designer, or manufacturer as appropriate, and "hermetic" ultimately represents a criteria defined by the user, designer, manufacturer, or other interested party.

Leak detection may be achieved, for example, by using a trace gas. The use of a tracer gas such as helium for leak testing is advantageous because it is a dry, fast, accurate and non-destructive method. In one embodiment of this technique, the supercapacitor 10 is placed in a helium environment. The supercapacitor 10 is subjected to pressurized helium gas. The supercapacitor 10 is then placed in a vacuum chamber connected to a detector (e.g. an atomic absorption unit) capable of monitoring the presence of helium. With known pressurization time, pressure and internal volume, the leakage rate of the ultracapacitor 10 can be determined.

In some embodiments, at least one lead (which may also be referred to herein as a "tab") is electrically coupled to a respective one of the current collectors 2. A plurality of leads (corresponding to the polarity of the supercapacitor 10) may be grouped together and coupled to respective terminals 8. Further, the terminals 8 may be coupled as an electrical connection, referred to as "contacts" (e.g., the housing 7 and an external electrode (also referred to herein, by convention, as one of a "feed-through" or a "pin"). Reference may be made to fig. 28 and 32-34.

E. Shell body

Fig. 11 depicts some aspects of an exemplary housing 7. The housing 7 provides structural and physical protection, among other things, for the ultracapacitor 10. In this embodiment, the housing 7 includes a body 20 of an annular cylindrical shape and a complementary cover 24. In this embodiment, the cover 24 includes a central portion that has been removed and filled with an electrical insulator 26. Lid feed-through 19 extends through electrical insulator 26 to provide stored energy to the user. In addition, the housing also includes an internal barrier 30.

While this embodiment describes only one feedthrough 19 on lid 24, it should be appreciated that the configuration of housing 7 is not limited to the embodiments discussed herein. For example, lid 24 may include a plurality of feedthroughs 19. In some embodiments, the body 20 includes a second similar cap 24 at the opposite end of the annular cylinder. Further, it should also be appreciated that the housing 7 is not limited to embodiments having a body 20 with an annular cylindrical shape. For example, the housing 7 may be of a clamshell design, a prismatic design, a bag or any other design suitable to the needs of the designer, manufacturer or user.

Referring now to fig. 12, an exemplary energy storage unit 12 is shown. In this embodiment, the energy storage unit 12 is a "jelly roll" type energy storage. In these embodiments, the energy storage material is rolled up into a tight package. A plurality of leads generally form each terminal 8 and provide electrical connection of the appropriate layers of the energy storage unit 12. Generally, each terminal 8 is electrically coupled to housing 7 (e.g., to a respective feedthrough 19 and/or directly to housing 7) when assembled. The energy storage unit 12 may take a variety of forms. There are typically at least two pluralities of leads (e.g., terminals 8), one for each current collector 2. For simplicity, only one of the terminals 8 is shown in fig. 12, 15 and 17.

Efficient sealing of the housing 7 is desired. That is, preventing intrusion of the external environment (e.g., air, moisture, etc.) helps to maintain the purity of the components of the energy storage unit 12. Furthermore, it prevents leakage of electrolyte 6 from the energy storage unit 12.

In this embodiment, the cap 24 is manufactured with an outer diameter designed to closely fit the inner diameter of the body 20. Upon assembly, the cover 24 may be welded into the body 20 to provide an airtight seal for the user. Exemplary welding techniques include laser welding and TIG welding, and may include other forms of welding as deemed appropriate.

Common materials for the housing 7 include stainless steel, aluminum, tantalum, titanium, nickel, copper, tin, various alloys, laminates, and the like. Structural materials such as some polymer-based materials may be used in the housing 7 (typically in combination with at least some metal components).

In some embodiments, the material used to construct the body 20 includes aluminum, which may include any type of aluminum or aluminum alloy (all of which are broadly referred to herein simply as "aluminum") deemed suitable by the designer or manufacturer. Various alloys, laminates, etc. may be disposed over (e.g., clad to) aluminum (aluminum exposed to the interior of the body 20). Other materials (e.g., structural or electrically insulating materials, such as some polymer-based materials) may be used to supplement the body and/or housing 7. The material disposed over the aluminum may likewise be selected as deemed appropriate by the designer or manufacturer.

In some embodiments, multiple layers of materials are used for the interior components. For example, aluminum may be clad with stainless steel to provide multiple layers of material in at least one terminal 8. In some of these embodiments, a portion of the aluminum may be removed to expose the stainless steel. The exposed stainless steel can then be used to attach terminal 8 to feedthrough 19 using a simple welding method.

The use of a clad material for the inner component may require a particular embodiment of the clad material. For example, it may be beneficial to use a clad material that includes aluminum (bottom layer), stainless steel and/or tantalum (middle layer), and aluminum (top layer), such that it limits the exposure of the stainless steel to the internal environment of the ultracapacitor 10. These embodiments may be improved by, for example, additional coating with a polymeric material (e.g., PTFE).

Thus, providing the housing 7 with a multilayer material provides an energy storage which exhibits a leakage current with a relatively low initial value compared to the prior art and which rises significantly slower over time. Notably, the leakage current of the energy storage remains at a usable (i.e., desirably low) level when the ultracapacitor 10 is exposed to ambient temperatures at which prior art capacitors would exhibit excessive initial leakage current values and/or the leakage current increases too quickly over time.

Furthermore, the supercapacitor 10 may exhibit other benefits resulting from reduced reaction between the housing 7 and the energy storage unit 12. For example, the Effective Series Resistance (ESR) of the energy storage may exhibit a relatively low value over time. Furthermore, undesired chemical reactions occurring in prior art capacitors often produce undesired results (e.g., gassing or bulging of the housing 7 with hermetically sealed housing). In both cases, this results in a loss of structural integrity of the housing 7 and/or hermetic sealing of the energy storage. Eventually, this can lead to leakage or catastrophic failure of the prior art capacitors. These effects can be significantly reduced or eliminated by application of the disclosed barriers.

By using multiple layers of material (e.g., cladding material), stainless steel can be incorporated into the housing 7, and thus components with glass-to-metal seals can be used. The components may be welded to the stainless steel side of the clad material using techniques such as laser or resistance welding, while the aluminum side of the clad material may be welded to other aluminum components (e.g., body 20).

In some embodiments, an insulating polymer may be used for the coated portion of the housing 7. In this way, it may be ensured that the components of the energy storage are only exposed to an acceptable type of metal (e.g. aluminium). Exemplary insulating polymers include PFA, FEP, TFE, and PTFE. Suitable polymers (or other materials) are limited only by the needs of the system designer or manufacturer and the properties of the respective materials. Reference may be made to fig. 23, which includes a small amount of insulating material 39 to limit exposure of electrolyte 6 to the stainless steel of sleeve 51 and feedthrough 19. In this embodiment, terminal 8 is coupled to feedthrough 19, for example by welding, and then coated with insulating material 39.

i shell cover

While this embodiment describes only one feedthrough 19 on lid 24, it should be appreciated that the configuration of housing 7 is not limited to the embodiments discussed herein. For example, lid 24 may include a plurality of feedthroughs 19. In some embodiments, body 20 includes a second similar cap 24 at the opposite end of the annular cylinder. Further, it should also be appreciated that the housing 7 is not limited to embodiments having a body 20 with an annular cylindrical shape. For example, the housing 7 may be a flip-top design, a prismatic design, a pouch, or any other design suitable to the needs of the designer, manufacturer, or user.

Referring now to fig. 18, aspects of an embodiment of a blank 34 of the lid 24 are shown. In fig. 18A, the blank 34 comprises multiple layers of material. The first material layer 41 is aluminum. The second material layer 42 is stainless steel. In the embodiment of fig. 18, stainless steel is clad to aluminum to provide a material exhibiting a desired combination of metallurgical properties. That is, in some embodiments provided herein, aluminum is exposed to the interior of the energy storage unit (i.e., housing) while stainless steel is exposed to the exterior. In this way, the favorable electrical properties of aluminum are enjoyed while being constructed in dependence on the structural properties (as well as the metallurgical properties, i.e., weldability) of stainless steel. The multilayer material may include additional layers as deemed appropriate.

As mentioned above, first material layer 41 is clad onto second material layer 42 (or first material layer 41 is clad with second material layer 42). Still referring to fig. 18A, in one embodiment, a blank 34 is provided using a sheet of flat material (as shown) to produce a flat lid 24. A portion of the second material layer 42 may be removed (e.g., around the perimeter of the cover 24) to facilitate attachment of the cover 24 to the body 20. In fig. 18B, another embodiment of the blank 34 is shown. In this embodiment, the blank 34 has a sheet of wrapping material formed into a concave configuration. In fig. 18C, the blank 34 has a sheet of wrapping material formed into a convex configuration. The cover 24 made from various embodiments of the blank 34 (e.g., those shown in fig. 18) is configured to support the body 20 welded to the housing 7. More specifically, the embodiment of fig. 18B is adapted to fit within the inner diameter of the body 20, while the embodiment of fig. 18C is adapted to fit over the outer diameter of the body 20. In many alternative embodiments, the layers of the cover material in the sheet may be reversed.

Referring now to fig. 19, an embodiment of an electrode assembly 50 is shown. The electrode assembly 50 is designed to fit within the blank 34 and provide electrical communication from the energy storage medium to the user. Generally, the electrode assembly 50 includes a sleeve (sleeve) 51. The sleeve 51 surrounds the insulator 26, and the insulator 26 in turn surrounds the feedthrough 19. In this embodiment, the sleeve 51 is an annular cylinder having a flanged top.

To assemble the lid 24, perforations (not shown) are made in the blank 34. The perforations have a geometry sized to match the electrode assembly 50. Thus, the electrode assembly 50 is inserted into the perforations of the blank 34. Once the electrode assembly 50 is inserted, the electrode assembly 50 may be affixed to the blank 34 by techniques such as welding. The weld may be a laser weld, which is welded around the circumference of the flange of the welding sleeve 51. Referring to fig. 20, a point 61 at which welding is performed is shown. In this embodiment, point 61 provides a relatively simple welding process for welding stainless steel to stainless steel in place. Accordingly, the teachings herein provide a location to securely weld the electrode assembly 50 to the blank 34.

The material used to construct the sleeve 51 may include various types of metals or metal alloys. In general, the material for the sleeve 51 is selected based on, for example, structural integrity and engageability (to the blank 34). Exemplary materials for the sleeve 51 include 304 stainless steel or 316 stainless steel. The materials used to construct feedthrough 19 may include various types of metals or metal alloys. In general, the material used for feedthrough 19 is selected based on, for example, structural integrity and electrical conductivity. Exemplary materials for the electrodes include 446 stainless steel or 52 alloy.

Generally, insulator 26 is bonded to sleeve 51 and feedthrough 19 by known techniques (i.e., glass-to-metal bonding). The materials used to construct the insulator 26 may include, but are not limited to, various types of glass, including high temperature glass, ceramic glass, or ceramic materials. In general, the material used for the insulator is selected based on, for example, structural integrity and electrical resistance (i.e., electrical insulation properties).

The use of components that rely on glass-to-metal bonding (e.g., the foregoing embodiments of the electrode assembly 50) as well as the use of various welding techniques provide hermetic sealing of the energy reservoir. Other components may also be used to provide a hermetic seal. The term "hermetic seal" as used herein generally refers to a seal that exhibits a leak rate no greater than the leak rate defined herein. However, it is believed that the actual sealing efficiency may be better than this standard.

Additional or other techniques for coupling the electrode assembly 50 to the blank 34 include the use of cement under the flange of the sleeve 51 (between the flange and the second material layer 42) as deemed appropriate by such techniques.

Referring now to fig. 21, the energy storage unit 12 is disposed within the body 20. At least one terminal 8 is suitably coupled (e.g., to feedthrough 19), and a cap 24 is mated with body 20 to provide ultracapacitor 10.

Once assembled, the cover 24 and body 20 may be sealed. Fig. 22 depicts various embodiments of an assembled energy storage (in this case, ultracapacitor 10). In fig. 22A, a flat blank 34 (see fig. 18A) is used to produce the flat lid 24. Once the cap 24 is disposed on the body 20, the cap 24 is welded to the body 20 to produce the seal 62. In this case, because the body 20 is an annular cylinder, welding is performed around the body 20 and the cap 24 to provide the seal 62. In a second embodiment, as shown in fig. 22B, a female blank 34 (see fig. 18B) is used to create the female lid 24. Once the cap 24 is placed on the body 20, the cap 24 and body 20 are welded to produce the seal 62. In a third embodiment, as shown in fig. 22C, a convex blank member 34 (see fig. 18C) is used to produce the convex cover 24. Once the cap 24 is disposed on the body 20, the cap 24 and body 20 may be welded to produce the seal 62.

Where appropriate, the cladding material may be removed (by techniques such as machining or etching, etc.) to expose the other metals in the multilayer material. Thus, in some embodiments, the seal 62 may comprise an aluminum-aluminum weld. The aluminum-aluminum welds may be supplemented with other fasteners as appropriate.

Other techniques may be used to seal the housing 7. For example, laser welding, TIG welding, resistance welding, ultrasonic welding, and other forms of mechanical seals may be used. It should be noted, however, that in general, conventional forms of mechanical sealing alone are not sufficient to provide a robust hermetic seal provided in the ultracapacitor 10.

Referring now to fig. 24, aspects of another embodiment of an assembled cover 24 are depicted. Fig. 24A depicts a template (i.e., blank 34) for providing the body of the lid 24. The size of the template generally matches the housing 7 of an appropriate type of energy storage unit (e.g., supercapacitor 10). The cover 24 may be formed by: initially providing a template forming template comprising a dome 37 (shown in fig. 24B) in the template; the dome 37 is then perforated to provide the channel 32 (shown in fig. 24C). Of course, the blank 34 (e.g., annular storage) may be stamped or otherwise manufactured so as to provide the aforementioned features simultaneously.

Generally, and with these embodiments in mind, the cover may be formed of aluminum or alloys thereof. However, the cover may be formed of any material deemed suitable by the manufacturer, user, designer, etc. For example, the cover 24 may be made of steel and passivated (i.e., coated with an inert coating) or prepared by other methods for the housing 7.

Referring now to fig. 25, another embodiment of an electrode assembly 50 is shown. In these embodiments, electrode assembly 50 includes feedthrough 19 and a hemispherical shaped material disposed about feedthrough 19. The hemispherical material acts as the insulator 26 and is generally shaped to conform to the dome 37. The hemispherical insulator 26 may be made of any suitable material to provide a hermetic seal while being resistant to the chemical effects of the electrolyte 6. Exemplary materials include PFA (perfluoroalkoxy resin), FEP (fluorinated ethylene propylene copolymer), PVF (polyvinyl fluoride), TFE (tetrafluoroethylene), CTFE (chlorotrifluoroethylene), PCTFE (polychlorotrifluoroethylene), ETFE (polyethylenetetrafluoroethylene), ECTFE (polyethylenechlorotrifluoroethylene), PTFE (polytetrafluoroethylene), another fluoropolymer-based material, and any other material that can exhibit similar properties (to varying degrees) and provide satisfactory performance (e.g., exhibits high resistance to dissolution, acid, among others, under conditions of high temperature, low cost, etc.).

The feedthrough 19 may be formed of aluminum or alloys thereof. However, feedthrough 19 may be formed from any material deemed suitable by a manufacturer, user, designer, etc. For example, the feedthrough 19 may be made of steel and passivated (i.e., coated with an inert coating such as silicon) or otherwise prepared for use in the electrode assembly 50. An exemplary technique for passivation includes depositing a coating of hydrogenated amorphous silicon on a surface of a substrate and functionalizing the coated substrate by exposing the substrate to a binder having at least one unsaturated hydrocarbon group under pressure and elevated temperature for an effective length of time. A coating of hydrogenated amorphous silicon is deposited by exposing the substrate to a silicon hydride gas under pressure and at an elevated temperature for an effective length of time.

Hemispherical insulator 26 may be sized relative to dome 37 such that a tight fit (i.e., a hermetic seal) is achieved when assembled into cap 24. The hemispherical insulator 26 need not be perfectly symmetrical or have a classical hemispherical proportion. That is, the hemispherical insulator 26 is substantially hemispherical, and may include, for example, fine tuning of scale, moderate flange (e.g., at the base), and other features as deemed appropriate. The hemispherical insulator 26 is generally formed of a uniform material, however, this is not a requirement. For example, the hemispherical insulator 26 may include air or gas in a torus (not shown) filled therein to provide the desired expansion or compressibility.

As shown in fig. 26, the electrode assembly 50 may be inserted into a template (i.e., the formed blank 34) to provide one embodiment of the lid 24 that includes a hemispherical hermetic seal.

As shown in fig. 27, in many embodiments, the retainer 43 may engage or otherwise mate with the bottom of the cover 24 (i.e., the portion of the cover 24 facing the interior of the housing 7 and facing the energy storage unit 12). The retainer 43 may be joined to the cover 24 by a variety of techniques, such as aluminum welding (e.g., laser, ultrasonic, etc.). Other techniques may be used for joining, including, for example, stamping (i.e., mechanical joining) and brazing. The engagement may occur, for example, along the perimeter of the retainer 43. Generally, engagement is provided to at least one engagement point to create the desired seal 71. At least one fastener (e.g., a plurality of rivets) may be used to seal the insulator 26 in the retainer 43.

In the embodiment of fig. 27, the cover 24 is of a female design (see fig. 18B). However, other designs may be used. For example, a convex cover 24 may be provided (fig. 18C), and an upper cover 24 may also be used (a variation of the embodiment of fig. 18C configured to fit as depicted in fig. 22C).

The materials for the lid and feedthrough 19 may be selected in consideration of the thermal expansion of the hemispherical insulator 26. Furthermore, the fabrication techniques may also be designed to account for thermal expansion. For example, upon assembly of the cap 24, the manufacturer may apply pressure to the hemispherical insulator 26, thereby compressing the hemispherical insulator 26 at least to some extent. In this way provision is made for the presence of at least some thermal expansion of the cover 24 without compromising the effectiveness of the hermetic seal.

To further illustrate the assembled supercapacitor, referring to fig. 28, a cross-sectional view of the supercapacitor 10 is provided. In this embodiment, the storage unit 12 is inserted and contained in the body 20. Each set of a plurality of leads is tied together and coupled to the housing 7 as one of the terminals 8. In some embodiments, a plurality of leads are coupled to the bottom (inside) of the body 20, thereby turning the body 20 into the negative contact 55. Likewise, another plurality of leads are tied together and coupled to feedthrough 19 to provide positive contact 56. The electrical isolation between the negative contact 55 and the positive contact 56 is maintained by the electrical insulator 26. Generally, the coupling of the leads is accomplished by welding, such as at least one of laser and ultrasonic welding. Of course, other techniques may be used as deemed appropriate.

inner barrier

Referring now to fig. 13, the housing 7 may include an internal barrier 30. In some embodiments, barrier 30 is a paint. In this embodiment, the barrier 30 is formed of Polytetrafluoroethylene (PTFE). Polytetrafluoroethylene (PTFE) exhibits various properties that make this composition well suited for barrier 30. PTFE has a melting point of about 327 degrees celsius, excellent dielectric properties, a coefficient of friction of about 0.05 to 0.10 (which is the third lowest of any known solid materials), high corrosion resistance, and other beneficial properties. Generally, the interior portion of the lid 24 may include a barrier 30 disposed thereon.

Other materials may also be used for the barrier 30. These other materials are formed from ceramics (any type of ceramic that may be suitable for the application and meet performance criteria), other polymers (preferably high temperature polymers), and the like. Exemplary other polymers include Perfluoroalkoxy (PFA) and Fluorinated Ethylene Propylene (FEP) and Ethylene Tetrafluoroethylene (ETFE).

The barrier 30 may include any material or combination of materials that provide for reducing electrochemical-type or other types of reactions between the energy storage cells 12 and the housing 7 or components of the housing 7. In some embodiments, the combination is embodied as a homogeneous dispersion of the different materials in a single layer. In further embodiments, the combination is embodied as different materials in multiple layers. Other combinations may be used. In short, barrier 30 may be considered to be at least one of an electrical insulator and chemically inert (i.e., exhibiting low reactivity), and thus, substantially resist or impede at least one of electrical and chemical interaction between storage unit 12 and housing 7. In some embodiments, the terms "low reactivity" and "low chemical reactivity" generally refer to a chemical interaction rate that is below a level of interest for the relevant party.

In general, the interior of the housing 7 may house a barrier 30 so as to cover all surfaces of the housing 7 exposed to the interior. At least one untreated region 31 may be included in the body 20 and on an outer surface 36 of the cover 24 (see fig. 14A). In some embodiments, untreated areas 31 (see fig. 14B) may be included to meet assembly requirements, such as areas to be sealed or connected (e.g., by welding).

The barrier 30 may be applied to the inner portion using conventional techniques. For example, in the case of PTFE, the barrier 30 may be applied by painting or spraying the barrier 30 onto the interior surface as a coating. A mask may be used as part of the method of ensuring that the untreated areas 31 retain the desired integrity. In short, a variety of techniques may be employed to provide the barrier 30.

In one exemplary embodiment, the thickness of barrier 30 is from about 3 mils to about 5 mils, while the material used for barrier 30 is a PFA-based material. In this embodiment, the surface for receiving the material constituting the barrier 30 is prepared, for example, with alumina by sand blasting. Once the surface is cleaned, the material is applied first as a liquid and then as a powder. The material is cured by a heat treatment process. In some embodiments, the heating cycle is at a temperature of about 370 degrees celsius for a duration of about 10 minutes to about 15 minutes. This results in continuous polishing of the barrier 30 that contains substantially no defects of pinhole size or smaller. Fig. 15 depicts the assembly of an embodiment of a supercapacitor 10 according to the teachings herein. In this embodiment, the supercapacitor 10 includes: a body 20 including a barrier 30 disposed therein; a lid 24 having a barrier 30 disposed therein; and an energy storage unit 12. During assembly, the cover 24 is disposed over the body 20. A first terminal 8 is electrically coupled to lid feedthrough 19 while a second terminal 8 is electrically coupled to housing 7, typically at the bottom, side, or above lid 24. In some embodiments, second terminal 8 is coupled to another feedthrough 19 (e.g., opposing lid 24).

With the barrier 30 disposed on the interior surface of the housing 7, electrochemical reactions and other reactions between the housing 7 and the electrolyte are substantially reduced or substantially eliminated. This is particularly evident at higher temperatures where the rates of chemical and other reactions are generally elevated.

Referring now to fig. 16, the relative performance of the supercapacitor 10 compared to other equivalent supercapacitors is shown. In fig. 16A, the leakage current of a prior art embodiment of a supercapacitor 10 is shown. In fig. 16B, the leakage current of an equivalent supercapacitor 10 including the barrier 30 is shown. In fig. 16B, the supercapacitor 10 is electrically equivalent to the supercapacitor of which the leakage current is shown in fig. 16A. In both cases, the housing 7 was stainless steel and the voltage applied to the cell was 1.75 volts and the electrolyte was not purified. The temperature was kept constant at 150 degrees celsius. In particular, the leakage current in fig. 16B shows a low initial value and does not significantly increase with time, while the leakage current in fig. 16A shows a relatively high initial value and significantly increases with time.

Generally, the barrier 30 provides a suitable material of a suitable thickness between the energy storage unit 12 and the housing 7. The barrier 30 may include a homogeneous mixture, a heterogeneous mixture, and/or at least one layer of material. The barrier 30 may provide complete coverage (i.e., provide coverage of the interior surface area of the housing except for the electrode contacts) or partial coverage. In some embodiments, barrier 30 is formed from multiple components. For example, consider the embodiment shown below and shown in fig. 8.

Referring to fig. 17, aspects of other embodiments are shown. In some embodiments, the energy storage unit 12 is disposed in an enclosure (envelope) 73. That is, the energy storage unit 12 has a barrier 30 disposed thereon, packaged thereover, or applied by other methods to separate the energy storage unit 12 from the housing 7 once assembled. The encapsulant 73 may be applied well before the energy storage unit 12 is enclosed in the housing 7. Thus, the use of the enclosure 73 may present certain advantages, such as to the manufacturer. (note that the enclosure 73 is shown loosely disposed on the energy storage unit 12 for illustrative purposes).

In some embodiments, the enclosure 73 is used in conjunction with a coating, wherein the coating is disposed on at least a portion of the interior surface. For example, in one embodiment, the coating is only disposed in areas where the enclosure 73 inside the housing 7 may be at least partially damaged (e.g., as the tab terminals 8). The encapsulant 73 forms an efficient barrier 30 with the coating.

Thus, the combination of barriers 30 may provide a supercapacitor exhibiting a leakage current with a lower initial value and a substantially slower increase in leakage current over time compared to the prior art. Notably, the leakage current of the supercapacitor is still at a practical (i.e., desirably low) level when the supercapacitor is exposed to ambient temperatures at which prior art capacitors would exhibit excessively large initial leakage current values and/or excessively rapid increases in leakage current over time.

Having thus described embodiments of the barrier 30 and many aspects thereof, it will be appreciated that the supercapacitor 10 may exhibit other benefits resulting from reduced reaction between the housing 7 and the energy storage medium 1. For example, the Effective Series Resistance (ESR) of the supercapacitor 10 may exhibit a relatively low value over time. Furthermore, the occurrence of undesired chemical reactions in prior art capacitors often produces undesired effects such as outgassing, or bulging of the housing in case the housing is hermetically sealed. In both cases, this results in a loss of structural integrity of the housing and/or hermetic sealing of the capacitor. Eventually, this can lead to leakage or catastrophic failure of the prior art capacitors. In some embodiments, these results can be significantly reduced or eliminated by the use of the disclosed barrier 30.

It should be recognized that the terms "barrier" and "coating" are not limited to the teachings herein. That is, any technique for applying a suitable material to the interior of the housing 7, body 20, and/or cover 24 may be used. For example, in other embodiments, barrier 30 is actually fabricated into or onto the material comprising housing body 20, which is then machined or shaped as appropriate to form the various components of housing 7. While considering some of the many possible techniques for applying the barrier 30, the material may be applied by roll-on (roll on), sputtering, sintering, laminating, printing, or by other methods as is equally suitable. In short, barrier 30 may be applied using any technique deemed appropriate by the manufacturer, designer, and/or user.

The materials used in barrier 30 may be selected based on, for example, the following properties: reactivity, dielectric value, melting point, adhesion to the material of the housing 7, coefficient of friction, cost, and other such factors. Combinations of materials (e.g., layered, mixed, or otherwise combined) can be used to provide desired properties.

In some embodiments, the use of a reinforced housing 7 (e.g., a housing 7 with a barrier 30) may limit degradation of the electrolyte 6. While barrier 30 illustrates one technique for providing a reinforced housing 7, other techniques may be employed. For example, the use of a housing 7 made of aluminum is advantageous due to the electrochemical properties of aluminum in the presence of the electrolyte 6. However, in view of the difficulty in the manufacture of aluminum, it has not been possible (to date) to construct an embodiment of the housing 7 that utilizes aluminum.

Additional embodiments of the housing 7 include those in which aluminum is present on all internal surfaces that may be exposed to the electrolyte, while providing the user with the ability to weld and hermetically seal the housing. Improved performance of the supercapacitor 10 may be achieved through reduced internal corrosion, reduction of problems associated with the use of different metals in the conductive medium, and other reasons. Advantageously, the housing 7 utilizes existing technology, such available electrode inserts (and may include those made from stainless steel, tantalum, or other advantageous materials and compositions) that include a glass-to-metal seal, and thus may be economically manufactured.

Although disclosed herein as embodiments suitable for the housing 7 of the ultracapacitor 10, these embodiments (as with the barrier 30) may be used with any type of energy storage deemed suitable and may include any type of viable technology. For example, other forms of energy storage may be used, including electrochemical cells, particularly lithium-based cells.

In general, the materials exposed to the interior of the housing 7 exhibit sufficiently low reactivity when exposed to the electrolyte 6 (i.e., the advanced electrolyte system of the present invention) and are thus merely illustrative of some embodiments and not limiting of the teachings herein.

F.Factors of general construction of capacitors

One important aspect to consider in the construction of the supercapacitor 10 is the maintenance of good chemical hygiene. To ensure the purity of the components, in many embodiments, the activated carbon, carbon fibers, rayon, carbon cloth, and/or nanotubes that make up the energy storage medium 1 of the two electrodes 3 are dried in a vacuum environment at an elevated temperature. The separator 5 is also dried at an elevated temperature in a vacuum environment. Once the electrodes 3 and separator 5 are dried under vacuum, they are encapsulated in the housing 7 without the need for final sealing or capping in an atmosphere of less than 50 parts per million (ppm) water. For example, the uncapped ultracapacitor 10 may be dried under vacuum throughout a temperature range of about 100 degrees Celsius to about 300 degrees Celsius. Once this final drying is complete, electrolyte 6 may be added and the housing 7 sealed in a relatively dry atmosphere (e.g., an atmosphere having less than about 50ppm moisture). Of course, other methods of assembly may be used, and the foregoing provides only some exemplary aspects of the assembly of the ultracapacitor 10.

The process of the invention

Certain methods of the invention for reducing impurities or making the devices of the invention are described herein below. Such a purification method is additionally applicable to any advanced electrolyte system of the present invention.

A.Method for reducing impurities

Aes contamination

In certain embodiments, the Advanced Electrolyte System (AES) of the invention is purified to remove contaminants and provide the desired enhanced performance characteristics described herein. Accordingly, the present disclosure provides a method of purifying AES, the method comprising: mixing water into an advanced electrolyte system to provide a first mixture; separating the first mixture; collecting the advanced electrolyte system from the first mixture; adding a solvent to the collected liquid to provide a second mixture; mixing carbon into the second mixture to provide a third mixture; separating the advanced electrolyte system from the third mixture to obtain a purified advanced electrolyte system. Generally, the process requires the selection of electrolyte, the addition of deionized water and activated carbon under controlled conditions. The deionized water and activated carbon are then removed to yield a substantially purified electrolyte. The purified electrolyte is particularly suitable for use in supercapacitors.

This method can be used to ensure high purity of the Advanced Electrolyte System (AES) of the present invention. It should be noted that while the method is expressed in terms of specific parameters (e.g., amounts, formulations, time, etc.), the expression is merely exemplary and illustrative of a method for purifying an electrolyte and is not intended to be limiting.

For example, the method may further comprise one or more of the following steps or features: heating the first mixture; wherein separating comprises leaving the first mixture undisturbed until the water and AES are substantially separated; wherein the solvent addition comprises addition of at least one of ethyl ether, isoprenylene (pentone), cycloprenone, hexane, cyclohexane, benzene, toluene, 1-4-dioxane, and chloroform; wherein the mixed carbon comprises mixed carbon powder; wherein mixing the carbon comprises substantially continuously agitating the third mixture; wherein separating the AES includes at least one of filtering the carbon from the third mixture and evaporating the solvent from the third mixture.

In a first step of the process for purifying the electrolyte, the electrolyte 6 (in some embodiments an ionic liquid) is mixed with deionized water and then raised to a moderate temperature for a period of time. In proof of concept, fifty (50) milliliters (ml) of ionic liquid was mixed with eight hundred fifty (850) milliliters (m1) of deionized water. The mixture was raised to a constant temperature of sixty (60) degrees celsius for about twelve (12) hours and continued stirring (about one hundred twenty (120) revolutions per minute (rpm)) was performed.

In a second step, the mixture of ionic liquid and deionized water is separated. In this example, the mixture was transferred through a funnel and then allowed to stand for about four (4) hours.

In a third step, the ionic liquid is collected. In this example, the aqueous phase of the mixture is at the bottom and the ionic liquid phase is at the top. The ionic liquid phase was transferred to another beaker.

In a fourth step, a solvent is mixed with the ionic liquid. In this example, a volume of about twenty-five (25) milliliters (ml) of ethyl acetate was mixed with the ionic liquid. The mixture is then raised to a moderate temperature and stirred for a period of time.

Although ethyl acetate is used as the solvent, the solvent may be at least one of the following: ethyl ether, isoprenylene (pentene), cycloprenone (cycloprenone), hexane, cyclohexane, benzene, toluene, 1-4-dioxane, chloroform, or any combination thereof, as well as other materials that exhibit suitable performance characteristics. Some desirable performance characteristics include those of non-polar solvents and high volatility.

In a fifth step, carbon powder is added to the mixture of ionic liquid and solvent. In this example, about twenty (20) weight percent (wt%) carbon (about 0.45 micron diameter) was added to the mixture.

In a sixth step, the ionic liquid is mixed again. In this example, the mixture with carbon powder was then constantly stirred (120rpm) overnight at about seventy (70) degrees celsius.

In a seventh step, the carbon and ethyl acetate are separated from the ionic liquid. In this example, a buchner funnel with a glass microfiber filter was used to separate the carbon. Multiple filtrations (3 times) were performed. The collected ionic liquid was then passed through a 0.2 micron syringe filter to remove substantially all carbon particles. In this example, the solvent is then separated from the ionic liquid by employing rotary evaporation. Specifically, a sample of the ionic liquid was stirred while the temperature was increased from seventy (70) degrees celsius to eighty (80) degrees celsius, and finally one hundred (100) degrees celsius. At each of the various temperatures, evaporation was carried out for about fifteen (15) minutes.

The method for purifying the electrolyte has proven to be very effective. For the sample ionic liquid, the water content was measured by titration with a titrator (model: AQC22) supplied by Mettler-Toledo Inc. of Columbus, Ohio. Halogen content was measured using an ISE apparatus (model: AQC22) supplied by Hanna Instruments of Woonsocket, Rhode Island. Standard solutions for the ISE instrument were obtained from Hanna and included HI 4007-03(1000ppm chlorine standard), HI 4010-03(1000ppm fluorine standard), HI 4000-00 (ISA for halogen electrodes), and HI 4010-00 (TISAB solution for fluorine electrodes only). Before the measurements were taken, the ISE instrument was calibrated with standard solutions using 0.1, 10, 100, and 1000 parts per million (ppm) standards mixed in deionized water. ISA buffer was added to the standard at a ratio of 1: 50 to measure Cl-ions. The results are shown in Table 3.

TABLE 3

Containing 1-butyl-1-methylpyrrolidine

And purification data of electrolytes of tetracyanoborate

Impurities	Front (ppm)	Thereafter (ppm)	Deionized water (ppm)
				Cl^-	5,300.90	769	9.23E-1
F-	75.61	10.61	1.10E-1
				H₂O	1080	20	--

Halide ions were measured using a four-step process. First, Cl was measured in deionized water^-Ions and F^-Ions. Next, a 0.01M ionic liquid solution was prepared with deionized water. Then, Cl was measured in the solution^-Ions and F^-Ions. The evaluation of the halogen content was then determined by subtracting the amount of ions in the water from the amount of ions in the solution.

The purification criteria for the electrolyte contaminant composition were also examined by analysis of the leakage current. Fig. 9 depicts leakage current of unpurified electrolyte in the supercapacitor 10. Fig. 10 depicts leakage current of purified electrolyte in a similarly configured supercapacitor 10. As can be seen, the initial leakage current is significantly reduced and the leakage current in the latter part of the measurement interval is suitably reduced. More information is provided based on the structure of each embodiment in table 4.

TABLE 4

Structure for testing super capacitor

Parameter(s)	FIG. 9	FIG. 10 shows a schematic view of a
			Cell size:	open Sub C	Open Sub C
Sleeve barrel:	coating with P870	Coating with P870
			Electrode material:	double-sided activated carbon (150/40)	Double-sided activated carbon (150/40)
An isolator:	glass fiber	Glass fiber
			Electrode size:	IE：233×34mm OE：256×34mm	IE：233×34mm OE：256×34mm
splicing:	0.005' aluminum (3 pieces connecting piece)	0.005' aluminum (3 pieces connecting piece)
			Temperature:	150℃	150℃
electrolyte:	unpurified AES	Purified AES

Other benefits are also realized, including an increase in the stability of the resistance and capacitance of the ultracapacitor 10.

The leakage current may be determined in a number of ways. Qualitatively, once the device reaches an equilibrium state, the leakage current can be considered as the current introduced into the device. In practice, it is always or almost always necessary to estimate the actual leakage current as an equilibrium state which is generally only asymptotically accessible. Thus, the leakage current in a given measurement can be estimated by measuring the current drawn into the supercapacitor 10 while the supercapacitor 10 is held at a substantially fixed voltage and exposed to a substantially fixed ambient temperature for a relatively long period of time. In some cases, a relatively long period of time may be determined by estimating the current time function as an exponential function, and then having several (e.g., about 3 to 5) characteristic time constants. Often for many supercapacitor technologies, such durations are from about 50 hours to about 100 hours. Alternatively, if such a long period of time is not feasible for any reason, it may be possible to deduce the leakage current again simply by estimating the current time function as an exponential function or any approximate function deemed appropriate. It is noted that the leakage current will generally depend on the ambient temperature. Therefore, in order to characterize the performance of a device at a certain temperature or in a certain temperature range, it is often important to expose the device to the ambient temperature of interest while measuring the leakage current.

Note that one way to reduce the volumetric leakage current at a particular temperature is to reduce the operating voltage at that temperature. Another way to reduce the volumetric leakage current at a particular temperature is to increase the void volume of the supercapacitor. Yet another way to reduce the leakage current is to reduce the load of the energy storage medium 1 on the electrodes 3.

Having disclosed aspects of embodiments for purifying electrolytes and ionic liquids, it will be appreciated that various embodiments may be implemented. Further, various techniques may be implemented. For example, steps, order of steps, etc. may be adjusted.

Water/moisture content and removal

The housing 7 of the sealed supercapacitor 10 may be opened and the storage unit 12 sampled to detect impurities. The water content from the electrodes, separator and electrolyte of cell 12 was measured using the karl fischer method. Three measurements were made and averaged.

Generally, the method for characterizing contaminants in a supercapacitor comprises opening the housing 7 to obtain its contents, sampling the contents and analyzing the sample. Techniques disclosed elsewhere herein may be used to support the characterization.

It should be noted that in order to ensure accurate measurement of impurities in the supercapacitor and its components, including electrodes, electrolyte and separators, assembly and disassembly may be performed in a suitable environment (e.g., an inert environment in a glove box).

By reducing the moisture content in the ultracapacitor 10 (e.g., to less than 500 parts per million (ppm) to less than 1000ppm relative to the mass and volume of electrolyte and impurities), the ultracapacitor 10 may operate more efficiently throughout a range of temperatures and voltages having a leakage current (I/L) of less than 10 amps/liter.

In one embodiment, the leakage current (I/L) at a particular temperature is measured by holding the voltage of the supercapacitor 10 constant at the rated voltage (i.e., the maximum rated operating voltage) for seventy-two (72) hours. During this time, the temperature is kept relatively constant at a certain temperature. The leakage current of the supercapacitor 10 is measured at the end of the measurement interval.

In some embodiments, the maximum voltage rating of the supercapacitor 10 is about 4V at room temperature. One way to ensure the performance of the supercapacitor 10 at elevated temperatures (e.g., in excess of 210 degrees celsius) is to derate (i.e., reduce) the voltage rating of the supercapacitor 10. For example, the voltage rating may be adjusted as low as about 0.5V so that extended operating durations may be obtained at higher temperatures.

B.Method for manufacturing super capacitor

In another embodiment, the present invention provides a method for manufacturing a supercapacitor, the method comprising the steps of: disposing an energy storage unit containing an energy storage medium within a housing; and filling the case with an Advanced Electrolyte System (AES) such that the ultracapacitor is manufactured to operate at a temperature range of about-40 degrees celsius to about 210 degrees celsius.

For example, in one particular embodiment, the AES comprises a Novel Electrolyte Entity (NEE), wherein the NEE is suitable for use in a high temperature supercapacitor. In certain embodiments, the ultracapacitor is configured to operate at a temperature within a temperature range of about 80 degrees celsius to about 210 degrees celsius (e.g., within a temperature range of about 80 degrees celsius to about 150 degrees celsius).

In a particular embodiment, the AES comprises a highly purified electrolyte, for example, wherein the highly purified electrolyte is suitable for use in a high temperature capacitor. In certain embodiments, the ultracapacitor is configured to operate at a temperature within a temperature range of about 80 degrees celsius to about 210 degrees celsius, for example, within a temperature range of about 80 degrees celsius to about 150 degrees celsius.

In a particular embodiment, the AES comprises an enhanced electrolyte combination, for example, wherein the enhanced electrolyte combination is suitable for use in both high temperature and low temperature supercapacitors. In certain embodiments, the ultracapacitor is configured to operate at a temperature within a temperature range of about-40 degrees celsius to about 150 degrees celsius, for example, within a temperature range of about-30 degrees celsius to about 125 degrees celsius.

In one embodiment, the manufactured supercapacitor is the supercapacitor described in section II above herein. Accordingly, and as noted above, advantages over existing electrolytes of known energy storage devices are selected from one or more of the following improvements: reduced overall resistance, improved long term stability of resistance, increased overall capacitance, improved long term stability of capacitance, increased energy density, improved voltage stability, reduced vapor pressure, wider temperature range performance of individual capacitors, improved temperature durability of individual capacitors, improved ease of manufacture, and improved cost effectiveness.

In certain embodiments, the disposing step further comprises pretreating the component of the ultracapacitor to reduce moisture therein, the component of the ultracapacitor comprising: at least one of an electrode, a separator, a lead, an assembled energy storage cell, and a housing. In a particular embodiment, the pre-treating includes heating the selected component substantially under vacuum at a temperature in a range of about 100 degrees celsius to about 150 degrees celsius. The pre-treating may include heating the selected component substantially under vacuum at a temperature in a range of about 150 degrees celsius to about 300 degrees celsius.

In certain embodiments, the disposing is performed in a substantially inert environment.

In certain embodiments, the constructing step includes selecting an interior surface material for the housing that exhibits a low chemical reactivity with respect to the electrolyte, which may also include including the interior surface material in a significant portion of the interior of the housing. The internal surface material may be at least one selected from aluminum, Polytetrafluoroethylene (PTFE), perfluoroalkoxy resin (PFA), fluorinated ethylene propylene copolymer (FEP), ethylene-tetrafluoroethylene copolymer (ETFE), and a ceramic material as the internal surface material.

In certain embodiments, the constructing step includes forming the housing from multiple layers of material, for example, wherein forming the housing from multiple layers of material includes disposing the weldable material on an exterior of the housing.

In certain embodiments, the constructing step comprises fabricating at least one of a cover and a body for the housing. The manufacturing step may include disposing a seal comprising an insulator and an electrode insulated from the housing in the housing. Further, providing the seal may include providing a glass-to-metal seal, e.g., welding the glass-to-metal seal to an outer surface of the housing. In a particular embodiment, providing a seal includes providing a hemispherical seal.

In certain embodiments, the constructing step comprises disposing a fill port in the housing for filling.

In certain embodiments, the method of manufacturing may further comprise manufacturing an energy storage cell, for example, by connecting an energy storage medium to a current collector to obtain an electrode; for example, at least one lead is connected to the electrode. In certain embodiments, connecting at least one lead to the electrode comprises disposing at least one reference mark on the electrode. In certain embodiments, connecting at least one lead to the electrode includes positioning each lead at a respective reference mark. In certain embodiments, connecting at least one lead comprises purging the energy storage medium from the current collector. In certain embodiments, connecting the at least one lead comprises ultrasonically welding the lead to the current collector.

The electrode may also be obtained by connecting a plurality of electrode elements made by connecting an energy storage medium with a current collector. The plurality of electrode elements may be connected by ultrasonically welding the connecting element to the current collector of one electrode element and the current collector of another electrode element.

In certain embodiments, fabricating the energy storage cell includes disposing a separator between at least two electrodes. And may further include aligning each of the electrodes with the separator.

In certain embodiments, fabricating the energy storage unit comprises encapsulating the at least two electrodes with the separator disposed therebetween, e.g., wherein the encapsulating comprises rolling the storage unit into a roll.

In certain embodiments, manufacturing the energy storage unit includes disposing the wrapper on the storage unit.

In certain embodiments, disposing the energy storage cell comprises bringing a plurality of leads together to provide the terminal, e.g., wherein bringing the plurality of leads together comprises aligning the leads together into a set of aligned leads to form the terminal. In certain embodiments, the method further comprises disposing a wrapper around the set of aligned leads; folding the set of aligned leads or coupling the set of aligned leads to contacts of the housing. Further, the coupling may include welding the set of aligned leads to the contacts, or welding the set of aligned leads to one of a jumper and a bridge for coupling to the contacts of the housing.

In certain embodiments, the method of manufacturing may further include electrically coupling at least one of the jumper and the bridge to a contact of the housing. In particular embodiments, it may further include substantially disposing an insulating material on the contacts on the interior of the housing.

In certain embodiments, the method of manufacturing may further include hermetically sealing the energy storage cell within the housing, for example, wherein hermetically sealing includes at least one of pulse welding, laser welding, resistance welding, and TIG welding the components of the housing together.

In certain embodiments, the method of manufacturing may further comprise mating at least one cover with the body to provide the housing, for example, wherein the cover comprises one of a female cover, a male cover, and a flat cover. In particular embodiments, the method may further comprise removing at least a portion of the multilayer material within the housing to provide a match.

In certain embodiments, the method of manufacture may further comprise purifying AES.

In certain embodiments, the method of manufacturing may further comprise disposing a fill port within the housing for filling, e.g., wherein filling comprises disposing AES in the housing through the fill port. In particular embodiments, the method further comprises sealing the fill port after filling is complete, e.g., fitting a compatible material into the fill port. In another step, such material may then be welded to the housing.

In certain embodiments, the filling step comprises drawing a vacuum on the filling port, for example, wherein the vacuum is less than about 150 mtorr, for example, wherein the vacuum is less than about 40 mtorr.

In certain embodiments, the filling step is performed in a substantially inert environment.

i. Manufacturing technique

Furthermore, it should be recognized that certain robust assembly techniques may be required to provide an efficient energy storage. Accordingly, some techniques for assembly are now discussed.

Once the supercapacitor 10 is manufactured, it can be used in high temperature applications with little or no leakage current and little increase in resistance. The ultracapacitors 10 described herein may efficiently operate at temperatures of about-40 degrees celsius to about 210 degrees celsius, with leakage current normalized across the entire operating voltage and temperature range in a device volume of less than 10 amperes per liter (a/L) volume of the device. In certain implementations, the capacitor can operate at a temperature spanning-40 degrees celsius to 210 degrees celsius.

As an overview, a method of assembling a cylindrically shaped supercapacitor 10 is provided. Starting with the electrodes 3, each electrode 3 is manufactured once the energy storage medium 1 is connected to the current collector 2. A plurality of leads are then coupled to each electrode 3 at appropriate locations. The plurality of electrodes 3 are then oriented and assembled with a suitable number of separators 5 therebetween to form the storage unit 12. The storage unit 12 may then be rolled into a cylinder and secured with a wrap. Generally, respective ones of the leads are then bundled to form the respective terminals 8.

Prior to incorporating the electrolyte 6 (i.e., the advanced electrolyte system of the present invention) into the ultracapacitor 10 (e.g., prior to or after assembling the storage unit 12), the various components of the ultracapacitor 10 may be dried to remove moisture. This can be done on unassembled parts (i.e. the empty housing 7 and each electrode 3 and each separator 5) and then on assembled parts (e.g. the storage unit 12).

Drying may be carried out, for example, in a vacuum environment at elevated temperature. Once dried, the storage unit 12 can then be enclosed in the housing 7 without final sealing or capping. In some embodiments, the encapsulation is performed in an atmosphere having less than 50 parts per million (ppm) of water. The uncapped ultracapacitor 10 may then be dried again. For example, the supercapacitor 10 may be dried under vacuum at a temperature ranging from about 100 degrees celsius to about 300 degrees celsius. Once this final drying is completed, the housing 7 may then be sealed in an atmosphere, for example, having less than 50ppm moisture.

In some embodiments, once the drying process (which may also be referred to as a "baking" process) is complete, the environment surrounding the component may be filled with an inert gas. Exemplary gases include argon, nitrogen, helium, and other gases (and combinations thereof) that exhibit similar properties.

In general, the filling port (a perforation in the surface of the housing 7) is included in the housing 7, or may be added later. Once the supercapacitor 10 has been filled with electrolyte 6 (i.e., the advanced electrolyte system of the present invention), the fill port can be closed. Closing the fill port may be accomplished, for example, by welding a material (e.g., a metal compatible with the housing 7) into or over the fill port. In some embodiments, the fill port may be temporarily closed prior to filling so that the ultracapacitor 10 may be moved to another environment for subsequent reopening, filling, and closing. However, as discussed herein, it is believed that the supercapacitor 10 is dried and filled in the same environment.

Many methods may be used to fill the housing 7 with the desired amount of advanced electrolyte system. In general, control over the filling process can provide for increased capacitance, reduced Equivalent Series Resistance (ESR), limited wastage of electrolyte, and the like. A vacuum filling method is provided as one non-limiting example of a technique for filling the housing 7 and wetting the storage unit 12 with electrolyte 6.

However, it should be noted first that measurements can be made to ensure that any material that may contaminate the components of the ultracapacitor 10 is clean, compatible, and dry. As a convention, it is believed that "good hygiene" is performed to ensure that the assembly process and components do not introduce contaminants into the ultracapacitor 10.

Under the "vacuum method", the container is arranged on the housing 7 around the filling port. A quantity of electrolyte 6 (i.e., the advanced electrolyte system of the present invention) is then placed in the container in an environment that is substantially free of oxygen and water (i.e., moisture). A vacuum is then drawn in the environment, thereby drawing any air from the housing and thereby simultaneously drawing the electrolyte 6 into the housing 7. The ambient environment may then be refilled with an inert gas (e.g., argon, nitrogen, etc., or some combination of inert gases) if desired. The supercapacitor 10 may be checked to see if a desired amount of electrolyte 6 has been drawn in. This process can be repeated as necessary until there is a desired amount of electrolyte 6 in the ultracapacitor 10.

In some embodiments, after filling the electrolyte 6 (i.e., the advanced electrolyte system of the present invention), a material may be mated to the fill port to seal the supercapacitor 10. For example, the material may be a metal that is compatible with the housing 7 and the electrolyte 6. In one embodiment, the material is press fit (force fit) into the fill port where the plug is primarily "cold welded". In particular embodiments, the press fit may be supplemented with other welding techniques, as discussed further herein.

Generally, assembly of the housing often involves disposing the storage unit 12 within the body 20 and filling the body 20 with an advanced electrolyte system. Another drying process may be performed. Exemplary drying includes heating the body 20 with the storage unit 12 and the advanced electrolyte system therein, typically under reduced pressure (e.g., vacuum). Once sufficient (optional) drying has occurred, the final assembly step can be performed. In a final step, the internal electrical connections are made, the cover 24 is installed, and the body 20 is hermetically sealed with the cover 24 by, for example, welding the cover 24 to the body 20.

In some embodiments, at least one of the housing 7 and the cover 24 is fabricated to include a material comprising a plurality of layers. For example, the first material layer may comprise aluminum and the second material layer stainless steel. In this embodiment, the stainless steel is clad to aluminum, thereby providing a material that exhibits a combination of desirable metallurgical properties. That is, in the embodiments provided herein, aluminum is exposed to the interior of the energy storage unit (i.e., housing) while stainless steel is exposed to the exterior. In this manner, the favorable electrical properties of aluminum are enjoyed while being constructed in dependence upon the structural properties (and metallurgical properties, i.e., weldability) of the stainless steel. The multilayer material may include additional layers as deemed appropriate. Advantageously, this provides a relatively simple welding process of welding stainless steel to stainless steel.

When the material used to construct the body 20 comprises aluminum, the designer or manufacturer deems any type of aluminum or aluminum alloy to be suitable (which is collectively referred to herein broadly as "aluminum"). Various alloys, laminates, and the like may be disposed (e.g., clad) over the aluminum (the aluminum exposed to the interior of the body 20). Additional materials (e.g., structural or electrically insulating materials, such as some polymer-based materials) may be used to supplement the body and/or housing 7. The material disposed over the aluminum may likewise be selected as deemed appropriate by the designer or manufacturer.

The use of aluminum is not necessary or essential. In short, the choice of materials may be provided to use any material deemed suitable by the designer, manufacturer or user, etc. Various factors may be considered, such as a reduction in electrochemical interaction with the electrolyte 6, structural properties, cost, and the like.

Embodiments of the supercapacitor 10 that exhibit a smaller volume may be fabricated in a prismatic form factor such that the electrodes 3 of the supercapacitor 10 are opposite each other, with at least one electrode 3 being in contact with the inside of the glass-to-metal seal and the other electrode being in contact with the inside of the housing or glass-to-metal seal.

The volume of a particular supercapacitor 10 can be enlarged by combining several storage units (e.g. several jelly rolls welded together) in one housing 7 such that they are electrically connected in parallel or in series.

In many embodiments, it is useful to use multiple supercapacitors 10 together to provide power. To provide reliable operation, individual ultracapacitors 10 may be tested prior to use. For various types of testing, each supercapacitor 10 may be tested as a single unit, in series or in parallel with a plurality of supercapacitors 10 attached. The use of different metals that are connected by a variety of techniques (e.g., by welding) can reduce the ESR of the connection as well as increase the strength of the connection. Aspects of the connection between the supercapacitors 10 will now be described.

In some embodiments, the ultracapacitor 10 includes two contacts. These two contacts are the glass-to-metal seal pin (i.e., feedthrough 19) and the entire remainder of the housing 7. When connecting a plurality of supercapacitors 10 in series, it is often desirable to couple the interconnections between the bottoms of the housings 7 (in the case of a cylindrical housing 7) so that the distance to the internal leads is minimized and therefore has minimal resistance. In these embodiments, opposite ends of the interconnect are often coupled to pins of a glass-to-metal seal.

A common type of welding, in the case of interconnects, involves the use of parallel tip resistance welders. The solder may be fabricated by aligning the ends of the interconnects over the pins and soldering the interconnects directly to the pins. The use of multiple solder connections will improve the strength and connection between the interconnect and the pins. In general, when soldering to a pin, the end of the interconnect is shaped to match the pin well to ensure that there is substantially no excess material overlapping the pin that could cause shorting.

An opposing tip resistance welder may be used to weld the interconnect to the pin, while an ultrasonic welder may be used to weld the interconnect with the bottom of the housing 7. When the included metals are compatible, brazing techniques may be used.

As for the material used in the interconnector, a common type of material used for the interconnector is nickel. Nickel may be used because it welds well to stainless steel and has a strong interface. Other metals and alloys may be used in place of nickel, for example, to reduce electrical resistance in the interconnect.

In general, the material selected for the interconnect is selected for its compatibility with the material in the pin and the material in the housing 7. Exemplary materials include copper, nickel, tantalum, aluminum, and nickel copper cladding. Other metals that may be used include silver, gold, brass, platinum and tin.

In some embodiments, such as where the pins (i.e., feedthroughs 19) are made of tantalum, the interconnects may utilize an intermediate metal, such as by employing short bridge connections. One exemplary bridge connection includes a tantalum strip, which has been improved by welding an aluminum/copper/nickel strip to the bridge using an opposing tip resistance welder. Then, a parallel resistance welder was used to weld the tantalum bars to the tantalum pins.

The bridge can also be used on the contacts of the housing 7. For example, a piece of nickel resistance welded to the bottom of the housing 7. The copper bar may then be ultrasonically welded to the nickel bridge. This technique helps to reduce the resistance of the cell interconnect. Using different metals for each connection may reduce the ESR of the interconnect between the series cells.

Having thus described various aspects of a robust ultracapacitor 10 that may be used in high temperature environments (i.e., up to about 210 degrees celsius), some other aspects are now provided and/or defined.

A wide variety of materials may be used to construct the supercapacitor 10. The integrity of the supercapacitor 10 is essential if oxygen and moisture are to be vented and the electrolyte 6 is to be prevented from escaping. To achieve this, seam welding and any other sealing points should meet the hermeticity criteria at the expected temperature range for operation. In addition, the materials selected should be compatible with other materials, such as ionic liquids and solvents, which can be used to formulate advanced electrolyte systems.

In some embodiments, feedthrough 19 is formed from a metal, such as at least one of the following materials: KOVAR^TM(Carpenter Technology Corporation of Reading, Pennsylvania, where KOVAR is a vacuum-melted, iron-nickel-cobalt, low expansion alloy whose chemical composition is controlled within narrow limits to ensure precise uniform thermal expansion properties), alloy 52 (a nickel-iron alloy suitable for sealing glass and ceramics to metals), tantalum, molybdenum, niobium, tungsten, stainless steel 446 (a ferritic, non-heat treatable stainless steel that provides good resistance to high temperature corrosion and oxidation), and titanium.

The body may be made of 300 series stainless steel (e.g., 304L, 316, and 316 alloys) using the glass-to-metal seal described previously. The body may also be made of metal, such as at least one of: various nickel alloys, such as Inconel (Inconel) (the family of austenitic nickel-chromium-based superalloys, which are oxidation and corrosion resistant materials well suited for extreme environments that experience pressure and heat), and Hastelloy (a highly corrosion resistant metal alloy that includes nickel and varying percentages of molybdenum, chromium, cobalt, iron, copper, manganese, titanium, zirconium, aluminum, carbon, and tungsten).

The insulating material between the feedthrough 19 and the surrounding body in a glass-to-metal seal is typically glass, which is of a composition that is proprietary to the respective manufacturer of the seal and depends on whether the seal is under pressure or whether it is mated. Other insulating materials may be used in the glass-to-metal seal. For example, a variety of polymers may be used in the seal. Thus, the term "glass-to-metal" seal is merely a description of the type of seal and is not intended to imply that the seal must comprise glass.

The housing 7 of the supercapacitor 10 may be made of, for example, types 304, 304L, 316 and 316L stainless steel. They may also be constructed from some aluminum alloys such as, but not limited to, 1100, 3003, 5052, 4043, and 6061. A variety of multilayer materials may be used and may include, for example, aluminum clad to stainless steel. Other non-limiting compatible metals that may be used include platinum, gold, rhodium, ruthenium, and silver.

Particular embodiments of glass-to-metal seals that have been used in the ultracapacitor 10 include two different types of glass-to-metal seals. The first is the SCHOTT from US located in Elmsford, NY, N.Y.. This embodiment uses stainless steel pins, glass insulators, and a stainless steel body. The second glass-to-metal seal was from HERMETIC SEAL TECHNOLOGY of Cincinnati (OH), Ohio. This second embodiment employs tantalum pins, glass insulators, and stainless steel bodies. Many embodiments of different sizes may be provided.

Additional embodiments of the glass-to-metal seal include embodiments using an aluminum seal and an aluminum body. Yet another embodiment of a glass-to-metal seal includes an aluminum seal using epoxy or other insulating material (e.g., ceramic or silicon).

Many aspects of the glass-to-metal seal may be configured as desired. For example, the dimensions of the housing and pins, and the materials of the pins and housing may be varied as desired. The pin may also be a tube or a solid pin, and there may be multiple pins in one cover. Although the most common types of materials for the pins are stainless steel alloys, copper-cored stainless steel, molybdenum, platinum-iridium, various nickel-iron alloys, tantalum, and other metals, some unconventional materials (e.g., aluminum) may be used. The housing is typically formed of stainless steel, titanium, and/or various other materials.

Various fastening techniques may be used in the combination of the supercapacitor 10. For example, in the case of welding, a variety of welding techniques may be used. The following is an exemplary list of weld types and multiple purposes for each type of weld may be used.

Ultrasonic welding can be used to: welding an aluminum tab to a current collector; welding the tabs to the bottom cladding cover; welding jumper wire tabs to a clad bridge connected to a glass-to-metal seal pin; and welding the glue wrap strips together, and the like. Pulse or resistance welding can be used to: welding a lead to the bottom of the container or to a pin; welding a lead to the current collector; welding a jumper wire to the cladding bridge; welding the clad bridge to the terminal 8; wire bonding to the bottom cover, etc. Laser welding can be used to: welding a stainless steel cover to the stainless steel container; welding a stainless steel bridge to a stainless steel glass-to-metal seal pin; and welding the plug to the fill port, etc. TIG welding can be used for: sealing the aluminum cover to the aluminum container; and welding aluminum seals into place, etc. Cold welding (pressing metals together with high force) can be used to seal a fill port by force-fitting an aluminum ball/nail into the fill port, etc.

Some advantageous embodiments of the manufacture

Certain advantageous embodiments are provided herein below, which are not intended to be limiting.

In a specific embodiment, and referring to fig. 29, components of an exemplary electrode 3 are shown. In this embodiment, the electrode 3 will serve as the negative electrode 3 (however, this designation is arbitrary and is for reference only).

As can be noted from the description, the separator 5 is generally longer and wider than the length and width of the energy storage medium 1 (and the current collector 2), at least in this embodiment. By using a larger separator 5, protection against short-circuiting of the negative electrode 3 with the positive electrode 3 is provided. The use of additional material in the isolator 5 also provides better electrical protection for the leads and the terminals 8.

Referring now to fig. 30, a side view of one embodiment of the storage unit 12 is provided. In this embodiment, the layered stacked energy storage medium 1 includes a first separator 5 and a second separator 5 such that the electrodes 3 are electrically isolated when the storage cells 12 are assembled into a rolled storage cell 23. It should be noted that the terms "positive" and "negative" are only arbitrary in terms of the assembly of the electrode 3 and the supercapacitor 10, and reference is made to the functionality when configuring in the supercapacitor 10 and storing charge therein. This convention generally applicable in the art does not imply that charge has been stored prior to assembly, or that any other aspect than providing physical identification of the different electrodes is implied.

Before winding the storage unit 12, the negative electrode 3 and the positive electrode 3 are aligned with respect to each other. The alignment of the electrodes 3 provides better performance for the supercapacitor 10, since the path length for ion transport is generally the smallest with the highest degree of alignment. Furthermore, by providing a high degree of alignment, an excessively large separator 5 is not included, and therefore the efficiency of the supercapacitor 10 is not compromised.

Referring now to fig. 31, one embodiment of the storage unit 12 is shown in which the electrode 3 is rolled into a rolled storage unit 23. One of the isolators 5 is present as the outermost layer of the storage unit 12 and separates the energy storage medium 1 from the interior of the housing 7.

"polarity matching" may be employed to match the polarity of the outermost electrode in the rolled storage unit 23 with the polarity of the body 20. For example, in some embodiments, the negative electrode 3 is on the outermost side of the tightly packed enclosure providing the rolled storage unit 23. In these embodiments, another degree of assurance against short circuits is provided. That is, when the negative electrode 3 is coupled to the body 20, the negative electrode 3 is arranged as an outermost electrode in the rolled storage unit 23. Thus, if the separator 5 fails (e.g., by mechanical wear caused by vibration of the supercapacitor 10 during use), the supercapacitor 10 will not fail due to a short circuit between the outermost electrodes in the rolled storage unit 23 and the body 20.

For each embodiment of rolled storage unit 23, reference mark 72 may be at least in separator 5. Reference marks 72 will be used to provide for positioning a lead on each electrode 3. In some embodiments, the location of the lead is provided by calculation. For example, the placement position of each lead wire can be evaluated by considering the inner diameter of the jelly roll and the total thickness of the combined separator 5 and electrode 3. However, practice has shown that using the reference mark 72 is more efficient and effective. The reference mark 72 may comprise, for example, a slit in the edge of the separator 5.

Generally, reference numeral 72 is used for each new specification of the storage unit 12. That is, because the new specifications of the storage unit 12 may require different thicknesses of at least one of the layers (in existing implementations), the use of existing reference marks may be at least somewhat inaccurate.

Generally, the reference mark 72 is embodied as a single radial line passing through the roll from its center to its periphery. Thus, when the leads are mounted along the reference mark 72, each lead will be aligned with the remaining leads (as shown in fig. 10). However, when the storage unit 12 is unrolled (an embodiment in which the storage unit 12 is a roll or will become a roll), the reference mark 72 can be considered a plurality of marks (as shown in fig. 32). By convention, regardless of the implementation or appearance of the markings of the storage unit 12, the identification of the location for the bonding wire is considered to involve the determination of a "reference mark 72" or "set of reference marks 72".

Referring now to fig. 32, once the reference mark 72 is established (e.g., by marking the rolled storage unit 12), a mounting site for mounting each lead is provided (i.e., depicted by reference mark 72). Once each mounting site is determined, for any given configuration specification of the storage unit 12, the relative position of each mounting site may be repeated for additional examples of the particular configuration of the storage unit 12.

Generally, each lead is coupled to a respective current collector 2 in the storage cell 12. In some embodiments, both the current collector 2 and the lead are made of aluminum. Generally, the leads are coupled to the collector 2 across the width W, although the leads may be coupled to only a portion of the width W. The coupling may be achieved by, for example, ultrasonically welding the lead to the current collector 2. To achieve coupling, at least some of the energy storage medium 1 may be removed (as appropriate) so that each lead is properly connected to the current collector 2. Other preparations and adjustments may be made to provide coupling as deemed appropriate.

In certain embodiments, relative reference numeral 73 may be included. That is, provided in the same manner as reference numeral 72, a set of opposing reference numerals 73 may be made to allow for the mounting of leads for opposite polarity. That is, reference mark 72 may be used to mount a lead to first electrode 3, such as negative electrode 3, while opposing reference mark 73 may be used to mount a lead to positive electrode 3. In embodiments where the rolled storage unit 23 is cylindrical, opposing reference marks 73 are disposed on opposite sides of the energy storage medium 1 and are longitudinally offset from the reference marks 72 (as depicted).

Note that in fig. 32, both the reference mark 72 and the opposite reference mark 73 are shown as being provided on the single electrode 3. That is, fig. 29 depicts an embodiment that is used only to illustrate the spatial (i.e., linear) relationship of the reference mark 72 to the opposing reference mark 73. This does not imply that the positive electrode 3 and the negative electrode 3 share the energy storage medium 1. However, it should be noted that in the case where the reference mark 72 and the opposite reference mark 73 are arranged by rolling up the storage unit 12 and then the separator 5 is marked, the reference mark 72 and the opposite reference mark 73 may be provided on a single separator 5 as it is. In practice, however, only one set of reference marks 72 and opposing reference marks 73 may be used to mount the lead for a given electrode 3. That is, it should be recognized that the embodiment depicted in fig. 32 is to be supplemented with another layer of energy storage medium 1 of another electrode 3 (which would have an opposite polarity).

As shown in fig. 33, the foregoing assembly technique results in a storage unit 12 that includes at least one set of alignment leads. The first set of aligned leads 91 is particularly useful when coupling the rolled storage unit 23 to one of the negative contact 55 and the positive contact 56, while the set of opposing aligned leads 92 provides for coupling the energy storage medium 1 to the opposing contacts (55, 56).

The rolled storage unit 23 may be surrounded by a wrapper 93. The wrapper 93 can be implemented in a number of embodiments. For example, wrapper 93 may be provided as KAPTON^TMTape (which is a polyimide film developed by DuPont of wilmington, delaware) or PTFE tape. In this embodiment, KAPTON^TMThe tape is wrapped around and adhered to the rolled storage unit 23. The wrap 93 may be provided as a tight-fitting wrap 93 free of adhesive, for example, slipped onto the rolled storage unit 23. The wrap 93 may be more representative of a bag, such as a bag that is generally rolled into the rolled storage unit 23 (e.g., envelope 73 discussed above). In some of these embodiments, wrap 93 may comprise a material that acts as a shrink-wrap (shrink-wrap) to provide efficient physical (in some cases efficient physical) of rolled storage unit 23In embodiments, chemical) encapsulation. Generally, the wrapper 93 is formed of a material that does not interfere with the electrochemical function of the supercapacitor 10. For example, wrap 93 may also provide partial coverage as needed to facilitate insertion of rolled storage unit 23.

In some embodiments, the negative and positive leads are located on opposite sides of the rolled storage unit 23 (in the case of jelly-roll type rolled storage unit 23, the negative and positive leads may be diametrically opposed). Generally, the placement of negative polarity leads and positive polarity leads on opposite sides of rolled storage unit 23 is done to help construct rolled storage unit 23 and to provide improved electrical isolation.

In some embodiments, once the aligned leads 91, 92 are assembled, each of the plurality of aligned leads 91, 92 is tied together (in place) such that a shrink-wrap (not shown) may be disposed around the plurality of aligned leads 91, 92. Generally, the shrink film package is formed of PTFE, but any compatible material may be used.

In some embodiments, once the shrink-wrap is placed around the aligned leads 91, the aligned leads 91 are folded into the shape assumed when assembling the ultracapacitor 10. That is, referring to fig. 34, it can be seen that the aligned leads are assumed to be "Z" shaped. After imparting a "Z-fold" to the aligned leads 91, 92 and applying the shrink wrap, the shrink wrap may be heated or otherwise activated to shrink the shrink wrap into position around the aligned leads 91, 92. Thus, in some embodiments, the aligned leads 91, 92 may be reinforced and protected by the encapsulation. The use of Z-folding is particularly useful when coupling the energy storage medium 1 to the feed-through 19 provided in the lid 24.

In addition, other embodiments for coupling each set of aligned leads 91, 92 (i.e., each terminal 8) to

respective contacts

55, 56 may be implemented. For example, in one embodiment, the intermediate leads are coupled to one of the feedthrough 19 and the housing 7 such that coupling with the sets of aligned leads 91, 92 is facilitated.

Furthermore, the materials used can be selected according to, for example, the following properties: reactivity, dielectric value, melting point, adhesion to other materials, solderability, coefficient of friction, cost, and other such factors. Combinations of materials (e.g., layered, mixed, or otherwise combined) may be used to provide the desired properties.

Specific supercapacitor embodiments

Some physical aspects of an exemplary ultracapacitor 10 of the present invention are shown below. It should be noted that in the following table, the term "tab" generally refers to "lead" as discussed above; the terms "bridge" and "jumper" also refer to some aspect of a lead (e.g., a bridge may be coupled to a feedthrough, or "pin," while a jumper may be used to connect the bridge to a tab or lead). The use of multiple connections can facilitate the assembly process and utilize certain assembly techniques. For example, the bridge may be laser welded or resistance welded to the pins and coupled to the jumper wires with ultrasonic welding.

TABLE 5

TABLE 6

TABLE 7

TABLE 8

Fig. 35-38 are graphs depicting the performance of these exemplary supercapacitors 10. Fig. 35 and 36 depict the performance of the supercapacitor 10 at 1.75 volts and 125 degrees celsius. Fig. 37 and 38 depict the performance of the supercapacitor 10 at 1.5 volts and 150 degrees celsius.

Generally, the ultracapacitor 10 may be used under a variety of environmental conditions and requirements. For example, the terminal voltage may be about 100mV to 10V. The ambient temperature may be about-40 degrees celsius to +210 degrees celsius. Typical high ambient temperatures are from +60 degrees celsius to +210 degrees celsius.

Fig. 39-43 are additional graphs depicting the performance of the exemplary supercapacitor 10. In these embodiments, the supercapacitor 10 is a closed unit (i.e., a housing). The supercapacitor was cycled 10 times with 100mA charged and discharged, charged to 0.5 volts, the resistance measured, discharged to 10mV, left for 10 seconds, and then cycled again.

Tables 11 and 12 provide comparative performance data for embodiments of the supercapacitor 10. Performance data for a number of operating conditions was collected as shown.

TABLE 9

Comparing performance data

Watch 10

Comparing performance data

Thus, the data provided in tables 9 and 10 indicate that the teachings herein enable the performance of supercapacitors under extreme conditions. Thus, the fabricated supercapacitor can, for example, exhibit a leakage current of less than about 1 mA/ml cell volume, and an ESR increase of less than about 100% (which is maintained at a voltage of less than about 2V and a temperature of less than about 150 degrees celsius) over 500 hours. Because one can trade off between various requirements of the supercapacitor (e.g., voltage and temperature), the rated performance of the supercapacitor (e.g., capacitance, rate of increase of ESR, etc.) can be managed, and can be tailored to specific needs. Note that with reference to the foregoing, a general definition of "nominal performance" is given, taking into account the values of the parameters describing the operating conditions.

FIGS. 35-43 depict a compound having a structure comprising 1-butyl-1-methylpyrrolidine

And performance of an exemplary supercapacitor of AES of tetracyanoborate at a temperature in a range of 125 degrees celsius to 210 degrees celsius.

FIGS. 44A and 44B depict a compound having a structure comprising 1-butyl-1-methylpiperidine

Performance data for an exemplary supercapacitor of AES of bis (trifluoromethylsulfonyl) imide.

FIGS. 45A and 45B depict a polymer having a polymer containing trihexyltetradecyl

Fig. 46A and 46B depict performance data for an exemplary supercapacitor with AES comprising butyltrimethylammonium bis (trifluoromethylsulfonyl) imide.

FIGS. 47A and 47B depict a compound having a structure comprising 1-butyl-1-methylpyrrolidine

And performance data at 125 degrees celsius for an exemplary supercapacitor of AES with tetracyanoborate.

FIGS. 48A and 48B and FIG. 49 depict a polycarbonate having a structure comprising propylene carbonate and 1-butyl-1-methylpyrrolidine

And performance data for an exemplary supercapacitor of AES in a mixture of tetracyanoborate salts, the mixture having about 37.5% by volume propylene carbonate; the capacitor was operated at 125 degrees celsius (fig. 48A and 48B) and at-40 degrees celsius (fig. 49). Another exemplary SuperSpeedThe capacitor comprises a capacitor containing 1-butyl-3-methylimidazole

AES of tetrafluoroborate.

Another exemplary supercapacitor tested included a capacitor containing 1-butyl-3-methylimidazole

AES of bis (trifluoromethylsulfonyl) imide.

Another exemplary supercapacitor tested included a capacitor containing 1-ethyl-3-methylimidazole

AES of tetrafluoroborate.

AES of tetracyanoborate.

Another exemplary supercapacitor tested included a capacitor containing 1-hexyl-3-methylimidazole

AES of tetracyanoborate.

Another exemplary supercapacitor tested included a capacitor containing 1-butyl-1-methylpyrrolidine

AES of bis (trifluoromethylsulfonyl) imide.

AES of tris (pentafluoroethyl) trifluorophosphate.

AES of tetracyanoborate.

AES of triflate.

AES of tetracyanoborate.

And 1-butyl-1-methylpyrrolidine

And AES of tetracyanoborate.

And AES of tetracyanoborate and ethylisopropylsulfone.

It should be noted that the measurement of capacitance and ESR (as shown in table 9 herein and elsewhere) follows generally known methods. Consider first a technique for measuring capacitance.

Capacitance can be measured in a number of ways. One method involves monitoring the voltage shown at the capacitor terminals while extracting (during "discharging") a known current from or supplying (during "charging") a known current to the supercapacitor. More specifically, the fact that an ideal capacitor follows the following equation can be exploited:

I＝C＊dV/dt，

where I represents the charging current, C represents the capacitance, and dV/dt represents the time derivative of the ideal capacitor voltage V. An ideal capacitor is a capacitor whose internal resistance is zero and whose capacitance is independent of voltage, etc. When the charging current I is constant, the voltage V is linear with time, so dV/dt can be calculated as the slope of the line or as Δ V/Δ T. However, this method is generally an approximation of the sum voltage difference (ESR reduction) provided by the effective series resistance of the capacitor, which should be taken into account when calculating or measuring the capacitance. The Effective Series Resistance (ESR) can generally be a lumped element (1um element) that approximates dissipation or other effects in a capacitor. The capacitor behavior often results from a circuit model of an ideal capacitor in series with a resistor having a resistance equal to the ESR. In general, this yields a good approximation to the actual capacitor behavior.

In a method of measuring capacitance, the effect of ESR reduction is largely negligible in the case where the internal resistance is substantially independent of voltage and the charging or discharging is substantially fixed. In this case, the ESR decrease may be approximated as a constant and naturally subtracted from the calculation of the voltage change during the constant current charging or discharging. The voltage change then substantially reflects the change in the charge stored on the capacitor. Therefore, the change in voltage can be calculated as an indication of capacitance.

For example, during galvanostatic discharge, galvanostatic I is known. The voltage change during discharge, Δ V, is measured and at a measured time interval Δ T, an approximation of the capacitance is obtained by dividing the current value I by the ratio Δ V/Δ T. When I is in amperes, av is in volts, and at is in seconds, the capacitance results will be in farads.

As for the evaluation of ESR, the Effective Series Resistance (ESR) of the supercapacitor can also be measured in a number of ways. One method involves monitoring the voltage shown at the capacitor terminals, while a known current is either extracted from (during "discharging") or supplied to (during "charging") the supercapacitor. More specifically, the fact that ESR follows the following equation can be utilized:

V＝I＊R，

where I represents the current effectively through the ESR, R represents the resistance value of the ESR, and V represents the voltage difference provided by the ESR (ESR decrease). The ESR may generally be a lumped element that approximates the dissipation or other effects in a supercapacitor. The supercapacitor behavior often derives from a circuit model of an ideal capacitor in series with a resistor with a resistance value equal to the ESR. In general, this yields a good approximation to the actual capacitor behavior.

In one method of measuring ESR, a discharge current can be started to be drawn from a capacitor in a quiescent state (a capacitor that is not charged or discharged with a large current). During the time interval in which the capacitor exhibits a voltage change due to a change in the stored charge on the capacitor that is less than the measured voltage change, the measured voltage change substantially reflects the ESR of the capacitor. Under these conditions, the instantaneous voltage change exhibited by the capacitor can be calculated as an indication of ESR.

For example, once the discharge current starts to be drawn from the capacitor, a transient voltage change Δ V may be exhibited during the measurement interval Δ T. As long as the capacitance C of the capacitor, by knowing the current discharge, results in a voltage change during the measurement interval Δ T that is less than the measured voltage change Δ V, it is possible to divide Δ V during the time interval Δ T by the discharge current I to obtain an approximation of the ESR. When I is in amperes and av is in volts, the ESR result will be in ohms.

Both ESR and capacitance may depend on ambient temperature. Thus, the relevant measurements may require the user to subject the supercapacitor 10 to a particular target ambient temperature during the measurement.

The performance requirements for leakage current are generally defined by the prevailing environmental conditions in a particular application. For example, for a capacitor having a volume of 20mL, the practical limit of leakage current can be reduced to below 100 mA.

The nominal value of the normalization parameter may be obtained by multiplying or dividing the normalization parameter (e.g., volume leakage current) by the normalization feature (e.g., volume). For example, a nominal leakage current for a supercapacitor with a volume leakage current of 10 mA/cubic centimeter and a volume of 50 cubic centimeter is 500mA, the product of the volume leakage current and the volume. Meanwhile, a supercapacitor with a volume ESR of 20 milli-ohms-cubic centimeter and a volume of 50 cubic centimeter has a nominal ESR of 0.4 milli-ohms quotient of the volume ESR and the volume.

Verification of filling effect of supercapacitor comprising AES

Furthermore, to illustrate how the filling method affects the supercapacitor 10, two similar embodiments of the supercapacitor 10 are constructed. One is filled under non-vacuum and the other is filled under vacuum. The electrical properties of the two embodiments are provided in table 11. By repeating such measurements, it is noted that improved performance is achieved by filling the supercapacitor 10 by applying a vacuum. It has been determined that, in general, it is desirable to reduce the pressure within the housing 7 to below about 150 mtorr, more particularly to below about 40 mtorr.

TABLE 11

Comparative Performance of filling method

Parameters (at 0.1V)	Under no vacuum	Under vacuum	Deviation of
				ESR@45°Φ	3.569 ohm	2.568 ohm	(-28％)
Capacitance @12mHz	155.87mF	182.3mF	(+14.49％)
				Phase @12mHz	79.19 degree	83 degrees	(+4.59％)

To evaluate the efficacy of the vacuum filling technique, two different pouch units (pouch cells) were tested. The pocket unit comprises two electrodes 3, each electrode 3 being based on a carbonaceous material. Each electrode 3 is oppositely arranged and faces each other. A separator 5 is provided between the electrodes 3 to prevent short-circuiting, and will be immersed in the electrolyte 6. Two outer tabs are used to provide four measurement points. The separator 5 used was a polyethylene separator 5, the total volume of the unit being about 0.468 ml.

C.Method of using a supercapacitor

The present invention is also intended to include any and all uses of the energy storage devices (e.g., ultracapacitors) described herein. This includes the use of the supercapacitor directly, or in other devices for any application. Such use is intended to include manufacturing, selling, or providing the supercapacitor to a user.

For example, in one embodiment, the present invention provides a method of using a High Temperature Rechargeable Energy Storage Device (HTRESD) (e.g., a supercapacitor), the method comprising the steps of: obtaining an HTRESD comprising an Advanced Electrolyte System (AES); cycling the HTRESD by alternately charging and discharging the HTRESD at least twice while maintaining a voltage across the HTRESD such that the HTRESD exhibits an initial peak power density of 0.01W/liter to 150 kW/liter such that the HTRESD operates at an ambient temperature in a temperature range of about-40 degrees celsius to about 210 degrees celsius. In certain embodiments, the temperature ranges from about-40 degrees celsius to about 150 degrees celsius; between about-40 degrees Celsius and about 125 degrees Celsius; between about 80 degrees Celsius to about 210 degrees Celsius; between about 80 degrees Celsius to about 175 degrees Celsius; between about 80 degrees Celsius to about 150 degrees Celsius; or between-40 degrees celsius and about 80 degrees celsius. In certain embodiments, the HTRESD exhibits an initial peak power density of about 0.01W/liter to about 10 kW/liter, for example, between about 0.01W/liter to about 5 kW/liter, for example, between about 0.01W/liter to about 2 kW/liter.

In another embodiment, the present invention provides a method of using a supercapacitor, the method comprising: obtaining the ultracapacitor of any one of claims 1 to 85, wherein the ultracapacitor exhibits a volumetric leakage current (mA/cubic centimeter) that is less than about 10 mA/cubic centimeter maintained at a substantially constant temperature within a range between about 100 degrees celsius to about 150 degrees celsius; and cycling the supercapacitor by alternately charging and discharging the supercapacitor at least twice while maintaining a voltage across the supercapacitor such that the supercapacitor exhibits an ESR increase less than about 300% after 20 hours when held at a substantially constant temperature in a range between about-40 degrees celsius to about 210 degrees celsius. In certain embodiments, the temperature range is between about-40 degrees celsius and about 150 degrees celsius; between about-40 degrees Celsius and about 125 degrees Celsius; between about 80 degrees Celsius and about 210 degrees Celsius; between about 80 degrees Celsius and about 175 degrees Celsius; between about 80 degrees Celsius and about 150 degrees Celsius; or between about-40 degrees celsius and about 80 degrees celsius.

In another embodiment, the present invention provides a method of providing a high temperature rechargeable energy storage device to a user, the method comprising: selecting a High Temperature Rechargeable Energy Storage Device (HTRESD) comprising an Advanced Electrolyte System (AES) that exhibits an initial peak power density of 0.01W/liter to 100 kW/liter and a durability period of at least 1 hour, such as at least 10 hours, such as at least 50 hours, such as at least 100 hours, such as at least 200 hours, such as at least 300 hours, such as at least 400 hours, such as at least 500 hours, such as at least 1000 hours, when exposed to an ambient temperature in a temperature range of about-40 degrees celsius to about 210 degrees celsius; and delivering the storage device such that the HTRESD is provided to the user.

In another embodiment, the present invention provides a method of providing a high temperature rechargeable energy storage device to a user, the method comprising: obtaining an ultracapacitor of any one of claims 1 to 85 that exhibits a volumetric leakage current (mA/cubic centimeter) less than about 10 mA/cubic centimeter when held at a substantially constant temperature in a range between about-40 degrees celsius to about 210 degrees celsius; and delivering the storage device such that the HTRESD is provided to the user.

Is incorporated by reference

All patents, published patent applications, and other references cited herein are expressly incorporated herein by reference in their entirety.

Equivalents of

Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific processes described herein. Such equivalents are considered to be within the scope of this invention and are covered by the following claims. Further, any numerical or alphabetic range provided herein is intended to include both the upper and lower limits of those ranges. Additionally, any list or grouping, at least in one embodiment, is intended to represent a shorthand or convenient manner of listing individual embodiments; thus, each portion of the list should be considered a separate embodiment.

It should be recognized that the teachings herein are merely exemplary and are not intended to limit the present invention. Further, those skilled in the art will recognize that additional components, configurations, arrangements, etc. may be implemented while remaining within the scope of the present invention. For example, the formulation of layers, electrodes, leads, terminals, contacts, feedthroughs, lids, and the like can differ from the embodiments disclosed herein. In general, the design and/or application of components of supercapacitors and supercapacitors utilizing electrodes is limited only by the needs of the system designer, manufacturer, operator and/or user and the needs that arise in any particular situation.

In addition, various other components may be included and employed for providing aspects of the teachings herein. For example, additional materials, combinations of materials, and/or redundancies of materials may be used to provide additional embodiments within the scope of the teachings herein.

While the invention has been described with reference to exemplary embodiments, it will be understood that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications will be appreciated to adapt a particular instrument, situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will be construed by the claims appended hereto.

The invention provides at least the following solutions:

scheme 1. a supercapacitor, comprising:

an Advanced Electrolyte System (AES) and an energy storage cell within a hermetically sealed housing, the cell electrically coupled to the positive contact and the negative contact, wherein the ultracapacitor is configured to operate at a temperature within a temperature range of about-40 degrees Celsius to about 210 degrees Celsius.

Scheme 2. the ultracapacitor of scheme 1, wherein the AES comprises a Novel Electrolyte Entity (NEE).

Scheme 3. the ultracapacitor of

scheme

1 or 2, wherein the NEE is suitable for use in a high temperature ultracapacitor.

Scheme 4. the ultracapacitor of any one of schemes 1 to 3, wherein the ultracapacitor is configured to operate at a temperature in a temperature range of between about 80 degrees celsius to about 210 degrees celsius.

The ultracapacitor of scheme 4, wherein the ultracapacitor is configured to operate at a temperature within a temperature range of about 80 degrees Celsius to about 150 degrees Celsius.

Scheme 6. the ultracapacitor of scheme 1, wherein the AES comprises a highly purified electrolyte.

Scheme 7. the supercapacitor according to

scheme

1 or 6, wherein the highly purified electrolyte is suitable for use in a high temperature supercapacitor.

The ultracapacitor of any one of

aspects

1, 6, or 7, wherein the ultracapacitor is configured to operate at a temperature within a temperature range of about 80 degrees Celsius to about 210 degrees Celsius.

The ultracapacitor of scheme 9, in accordance with scheme 8, wherein the ultracapacitor is configured to operate at a temperature in a temperature range between about 80 degrees Celsius to about 150 degrees Celsius.

Scheme 10. the supercapacitor according to scheme 1, wherein the AES comprises an enhanced electrolyte combination.

Scheme 11. the supercapacitor according to

scheme

1 or 10, wherein the enhanced electrolyte combination is suitable for use in both high temperature supercapacitors and low temperature supercapacitors.

The ultracapacitor of any one of

aspects

1, 10, or 11, wherein the ultracapacitor is configured to operate at a temperature in a temperature range between about-40 degrees Celsius to about 150 degrees Celsius.

The ultracapacitor of scheme 12, wherein the ultracapacitor is configured to operate at a temperature within a temperature range of about-30 degrees Celsius to about 125 degrees Celsius.

Scheme 14. the ultracapacitor of any one of schemes 1 to 13, wherein the advantages over existing electrolytes of known energy storage devices are selected from one or more of the following improvements: reduced overall resistance, improved long term stability of resistance, increased overall capacitance, improved long term stability of capacitance, increased energy density, improved voltage stability, reduced vapor pressure, wider temperature range performance of individual capacitors, improved temperature durability of individual capacitors, improved ease of manufacture, and improved cost effectiveness.

The ultracapacitor of any one of aspects 1 to 14, wherein the energy storage cell comprises a positive electrode and a negative electrode.

The ultracapacitor of any one of aspects 1 to 15, wherein at least one of the electrodes comprises a carbonaceous energy storage medium.

Scheme 17. the ultracapacitor as in scheme 16, wherein the carbonaceous energy storage media comprises carbon nanotubes.

The ultracapacitor as in scheme 16, wherein the carbonaceous energy storage media comprises at least one of activated carbon, carbon fiber, rayon, graphene, aerogel, carbon cloth, and carbon nanotubes in a variety of forms.

The ultracapacitor of any one of aspects 1 to 18, wherein each electrode comprises a current collector.

Scheme 20. the supercapacitor according to

scheme

2 or 10, wherein the AES is further purified to reduce impurity content.

Scheme 21 the ultracapacitor of any one of schemes 1 to 20, wherein content of halide ions in the electrolyte is less than about 1000 parts per million.

The ultracapacitor of scheme 21, wherein content of halide ions in the electrolyte is less than about 500 parts per million.

Scheme 23. the ultracapacitor of scheme 21, wherein content of halide ions in the electrolyte is less than about 100 parts per million.

Scheme 24. the ultracapacitor of scheme 21, wherein content of halide ions in the electrolyte is less than about 50 parts per million.

Scheme 25. the ultracapacitor of any one of schemes 21 to 24, the halide in the electrolyte is selected from one or more of the halides selected from chloride, bromide, fluoride, and iodide.

Scheme 26. the ultracapacitor as in any one of schemes 1 to 25, wherein a total concentration of metal species in the electrolyte is less than about 1000 parts per million.

Scheme 27. the ultracapacitor as in scheme 26, wherein the metallic species is selected from one or more metals selected from Cd, Co, Cr, Cu, Fe, K, Li, Mo, Na, Ni, Pb, and Zn.

Scheme 28. the ultracapacitor as in scheme 26, wherein the metallic species is selected from one or more alloys of metals selected from Cd, Co, Cr, Cu, Fe, K, Li, Mo, Na, Ni, Pb, and Zn.

Scheme 29. the ultracapacitor as in scheme 26, wherein the metallic species is selected from one or more oxides of metals selected from Cd, Co, Cr, Cu, Fe, K, Li, Mo, Na, Ni, Pb, and Zn.

The ultracapacitor of any one of aspects 20 to 29, wherein a total concentration of impurities in the electrolyte is less than about 1000 parts per million.

Scheme 31 the supercapacitor according to any one of schemes 20 to 30, wherein the impurities are selected from one or more of ethyl bromide, ethyl chloride, 1-bromobutane, 1-chlorobutane, 1-methylimidazole, ethyl acetate and dichloromethane.

The ultracapacitor of any one of aspects 20 to 31, wherein a total water content in the electrolyte is less than about 500 parts per million.

Scheme 33 the ultracapacitor of scheme 32, wherein a total water content in the electrolyte is less than about 100 parts per million.

The ultracapacitor of scheme 32, wherein a total water content in the electrolyte is less than about 50 parts per million.

The ultracapacitor of scheme 32, wherein a total water content in the electrolyte is less than about 20 parts per million.

Scheme 36. the ultracapacitor of any one of schemes 1 to 35, wherein the housing comprises a barrier disposed over a substantial portion of an interior surface thereof.

Scheme 37 the ultracapacitor of scheme 36, wherein the barrier comprises at least one of Polytetrafluoroethylene (PTFE), perfluoroalkoxy resin (PFA), fluorinated ethylene propylene copolymer (FEP), ethylene tetrafluoroethylene copolymer (ETFE).

Scheme 38. the ultracapacitor as in scheme 36, wherein the barrier comprises a ceramic material.

Scheme 39. the ultracapacitor as in scheme 36, wherein the barrier comprises a material that exhibits corrosion resistance, desirable dielectric properties, and low electrochemical reactivity.

Scheme 40. the ultracapacitor as in scheme 36, wherein the barrier comprises a plurality of material layers.

Scheme 41. the ultracapacitor of any one of schemes 1 to 40, wherein the housing comprises a multilayer material.

Scheme 42. the ultracapacitor as in scheme 41, wherein the multilayer material comprises a first material overlaid onto a second material.

Scheme 43. the ultracapacitor as in scheme 41, wherein the multilayer material comprises at least one of steel, tantalum, and aluminum.

The ultracapacitor of any one of aspects 1 to 43, wherein the housing comprises at least one hemispherical seal.

Scheme 45. the ultracapacitor of any one of schemes 1 to 44, wherein the housing comprises at least one glass-to-metal seal.

Scheme 46. the ultracapacitor as in scheme 45, wherein a pin of the glass-to-metal seal provides one of the contacts.

Scheme 47. the ultracapacitor of scheme 45, wherein the glass-to-metal seal comprises a feedthrough composed of a material selected from the group consisting of: iron-nickel-cobalt alloys, nickel-iron alloys, tantalum, molybdenum, niobium, tungsten, and certain forms of stainless steel and titanium.

The ultracapacitor as in aspect 45, wherein the glass-to-metal seal comprises a body comprised of at least one material selected from the group consisting of: nickel, molybdenum, chromium, cobalt, iron, copper, manganese, titanium, zirconium, aluminum, carbon, and tungsten, and alloys thereof.

Scheme 49 the ultracapacitor of any one of schemes 1 to 48, wherein the energy storage unit comprises a separator to provide electrical isolation between a positive electrode and a negative electrode.

Scheme 50. the ultracapacitor as in scheme 49, wherein the isolator packComprises polyamide, Polytetrafluoroethylene (PTFE), polyether ether ketone (PEEK), and aluminum oxide (Al)₂O₃) Glass fibers, glass fiber reinforced plastic, or any combination thereof.

Scheme 51. the ultracapacitor of scheme 49 or 50, wherein the separator is substantially free of moisture.

Scheme 52. the ultracapacitor of scheme 49, wherein the isolator is substantially hydrophobic.

Scheme 53. the ultracapacitor of any one of schemes 1 to 52, the hermetic seal exhibits no greater than about 5.0 x 10^-6atm-cubic centimeter per second leak rate.

Scheme 54. the ultracapacitor of any one of schemes 1 to 52, the hermetic seal exhibits no greater than about 5.0 x 10^-7atm-cubic centimeter per second leak rate.

Scheme 55 the ultracapacitor of any one of schemes 1 to 52, the hermetic seal exhibiting no greater than about 5.0 x 10^-8atm-cubic centimeter per second leak rate.

Scheme 56. the ultracapacitor of any one of schemes 1 to 52, the hermetic seal exhibiting no greater than about 5.0 x 10^-9atm-cubic centimeter per second leak rate.

Scheme 57. the ultracapacitor of any one of schemes 1 to 52, the hermetic seal exhibiting no greater than about 5.0 x 10^-10atm-cubic centimeter per second leak rate.

The ultracapacitor of any one of aspects 1 to 57, wherein at least one contact is configured to mate to another contact of another ultracapacitor.

Scheme 59. the ultracapacitor of any one of schemes 1 to 59, wherein the storage unit comprises a wrapper disposed over an exterior thereof.

Scheme 60. the ultracapacitor as in scheme 59, wherein the wrapper comprises one of PTFE and polyimide.

Scheme 61 the ultracapacitor of any one of schemes 1 to 60, wherein volumetric leakage current is less than about 1000 milliamps/liter over the temperature range.

Scheme 62. the ultracapacitor of any one of schemes 1 to 61, wherein a volumetric leakage current is less than about 1000 milliamps/liter over a particular voltage range.

Scheme 63 the ultracapacitor of any one of schemes 1 to 62, wherein a moisture level within the housing is less than about 1000 parts per million (ppm).

The ultracapacitor of scheme 63, wherein the moisture level within the housing is less than about 500 parts per million (ppm).

The ultracapacitor of scheme 63, wherein the moisture level within the housing is less than about 350 parts per million (ppm).

Scheme 66. the ultracapacitor of any one of schemes 1 to 65, comprising a moisture content in an electrode of the ultracapacitor that is less than about 1000 ppm.

Scheme 67. the ultracapacitor of scheme 66, comprising a moisture content in an electrode of the ultracapacitor that is less than about 500 ppm.

Scheme 68. the ultracapacitor of scheme 66, wherein a moisture level in the electrode of the ultracapacitor is less than about 350 parts per million (ppm).

Scheme 69. the ultracapacitor of any one of schemes 1 to 68, comprising a moisture content in a separator of the ultracapacitor that is less than about 1000 ppm.

Scheme 70. the ultracapacitor of scheme 69, comprising a moisture content in a separator of the ultracapacitor that is less than about 500 ppm.

Scheme 71. the ultracapacitor of scheme 69, having a moisture level in the separator of less than about 160 parts per million (ppm).

Scheme 72 the ultracapacitor of any one of schemes 1 to 71, wherein a chloride ion content is less than about 300ppm for one of the components selected from the group consisting of an electrode, an electrolyte, and a separator.

Scheme 73. the ultracapacitor of any one of schemes 1 to 72, wherein a volumetric leakage current (mA/cubic centimeter) of the ultracapacitor is less than about 10 mA/cubic centimeter while maintaining a substantially constant temperature.

Scheme 74. the ultracapacitor of scheme 73, wherein a volumetric leakage current of the ultracapacitor is less than about 1 mA/cubic centimeter while maintaining a substantially constant temperature.

Scheme 75. the ultracapacitor of scheme 73, wherein a volumetric leakage current of the ultracapacitor is greater than about 0.0001 mA/cubic centimeter while maintaining a substantially constant temperature.

Scheme 76 the ultracapacitor of scheme 73, wherein a volumetric capacitance of the ultracapacitor is between about 6F/cubic centimeter and about 1 mF/cubic centimeter.

Scheme 77. the ultracapacitor of scheme 73, wherein a volumetric capacitance of the ultracapacitor is between about 10F/cubic centimeter and about 5F/cubic centimeter.

Scheme 78 the ultracapacitor of scheme 73, wherein a volumetric capacitance of the ultracapacitor is between about 50F/cubic centimeter and about 8F/cubic centimeter.

Scheme 79. the ultracapacitor of scheme 73, wherein a volumetric ESR of the ultracapacitor is between about 20 and 200 milliohms-cubic centimeters.

Scheme 80 the ultracapacitor of scheme 73, wherein a volumetric ESR of the ultracapacitor is between about 150 milliohms-cubic centimeter and 2 ohms-cubic centimeter.

Scheme 81. the ultracapacitor of scheme 73, further exhibiting a volumetric ESR of the ultracapacitor between about 1.5 and 200 ohms-cubic centimeters.

Scheme 82. the ultracapacitor of scheme 73, further exhibiting a volumetric ESR of the ultracapacitor between about 150 and 2000 ohms-cubic centimeters.

The ultracapacitor of scheme 73, wherein the ultracapacitor exhibits a decrease in capacitance of less than about 60 percent when held at a constant voltage for at least 20 hours.

The ultracapacitor of scheme 73, wherein the ultracapacitor exhibits an ESR increase less than about 300 percent when held at a constant voltage for at least 20 hours.

Scheme 85. the method of scheme 73, wherein the ultracapacitor exhibits a capacitance decrease less than about 60 percent when held at a constant voltage.

Scheme 86. a method for manufacturing an ultracapacitor, comprising the steps of:

disposing an energy storage unit containing an energy storage medium within a housing; and

filling the case with an Advanced Electrolyte System (AES) such that the ultracapacitor is manufactured to operate at a temperature range of about-40 degrees celsius to about 210 degrees celsius.

Scheme 87. the method of scheme 86, wherein the AES comprises a Novel Electrolyte Entity (NEE).

Scheme 88. the method of scheme 86 or 87, wherein the NEE is suitable for use in a high temperature supercapacitor.

The method of any of schemes 86-88, wherein the ultracapacitor is configured to operate at a temperature within a temperature range of about 80 degrees celsius to about 210 degrees celsius.

Scheme 90. the method of scheme 89, wherein the ultracapacitor is configured to operate at a temperature in a temperature range of between about 80 degrees celsius to about 150 degrees celsius.

Scheme 91 the method of scheme 86, wherein the AES comprises a highly purified electrolyte.

Scheme 92. the method of scheme 86 or 91, wherein the highly purified electrolyte is suitable for use in a high temperature supercapacitor.

The method of any of

schemes

86, 91, or 92, wherein the ultracapacitor is configured to operate at a temperature within a temperature range of about 80 degrees celsius to about 210 degrees celsius.

Scheme 94. the method of scheme 93, wherein the ultracapacitor is configured to operate at a temperature in a temperature range of between about 80 degrees celsius to about 150 degrees celsius.

Scheme 95. the method of scheme 86, wherein the AES comprises an enhanced electrolyte combination.

Scheme 96. the method of scheme 86 or 95, wherein the enhanced electrolyte combination is suitable for use in both high temperature and low temperature supercapacitors.

Scheme 97 the method of any of schemes 86, 95, or 96, wherein the ultracapacitor is configured to operate at a temperature in a temperature range of about-40 degrees celsius to about 150 degrees celsius.

Scheme 98. the method of scheme 97, wherein the ultracapacitor is configured to operate at a temperature in a temperature range from about-30 degrees celsius to about 125 degrees celsius.

Scheme 99. the method of any of schemes 86-98, wherein the advantage over existing electrolytes of known energy storage devices is selected from one or more of the following improvements: reduced overall resistance, improved long term stability of resistance, increased overall capacitance, improved long term stability of capacitance, increased energy density, improved voltage stability, reduced vapor pressure, wider temperature range performance of individual capacitors, improved temperature durability of individual capacitors, improved ease of manufacture, and improved cost effectiveness.

Scheme 100. the method of scheme 72, wherein the manufactured ultracapacitor is the ultracapacitor of any one of schemes 1 to 85.

Scheme 101. the method of any of schemes 86 to 100, wherein the disposing further comprises pretreating the component of the ultracapacitor to reduce moisture therein, the component of the ultracapacitor comprising: at least one of an electrode, a separator, a lead, an assembled energy storage unit, and the housing.

Scheme 102. the method of scheme 101, wherein the pre-treating comprises heating the selected part substantially under vacuum at a temperature in a range of about 100 degrees celsius to about 150 degrees celsius.

Scheme 103. the method of scheme 101, wherein the pre-treating comprises heating the selected part substantially under vacuum at a temperature in a range of about 150 degrees celsius to about 300 degrees celsius.

Scheme 104. the method of any of schemes 86 to 103, wherein the disposing is performed in a substantially inert environment.

Scheme 105. the method of any of schemes 86-104, wherein the constructing comprises selecting an interior surface material for the housing that exhibits a low chemical reactivity with respect to the electrolyte.

Scheme 106. the method of scheme 105, further comprising introducing the interior surface material in a substantial portion of the interior of the housing.

Scheme 107. the method of scheme 105 or 106, wherein the constructing comprises selecting at least one of aluminum, Polytetrafluoroethylene (PTFE), perfluoroalkoxy resin (PFA), fluorinated ethylene propylene copolymer (FEP), ethylene-tetrafluoroethylene copolymer (ETFE), and ceramic material as the inner surface material.

Scheme 108. the method of any of schemes 86 to 104, wherein the constructing comprises forming the housing from multiple layers of material.

Scheme 109. the method of scheme 108, wherein the forming the housing from multiple layers of material includes disposing a weldable material on an exterior of the housing.

Scheme 110. the method of any of schemes 86 to 109, wherein the constructing comprises fabricating at least one of a cover and a body for the housing.

Scheme 111. the method of any of schemes 86 to 110, wherein the constructing comprises disposing a fill port in the housing to effect the filling.

Scheme 112. the method of scheme 110, wherein the fabricating comprises disposing a seal comprising an insulator and an electrode insulated from the housing in the housing.

Scheme 113 the method of scheme 112, wherein providing the seal comprises providing a glass-to-metal seal.

Scheme 114. the method of scheme 112, wherein providing the seal comprises providing a hemispherical seal.

Scheme 115 the method of scheme 113, wherein disposing the glass-to-metal seal comprises welding the glass-to-metal seal to an outer surface of the housing.

Scheme 116 the method of any of schemes 86-115, further comprising fabricating the energy storage unit.

Scheme 117 the method of scheme 116, wherein fabricating the energy storage cell comprises obtaining an electrode by connecting an energy storage medium with a current collector.

Scheme 118 the method of scheme 117, wherein obtaining the electrode comprises connecting a plurality of electrode elements fabricated by connecting an energy storage medium to a current collector.

Scheme 119. the method of scheme 118, wherein connecting the plurality of electrode elements comprises ultrasonically welding a connecting element to a current collector of one electrode element and ultrasonically welding a connecting element to a current collector of another electrode element.

Scheme 120. the method of scheme 116, wherein fabricating the energy storage cell comprises connecting at least one lead to an electrode.

Scheme 121. the method of scheme 120, wherein connecting at least one lead to the electrode comprises disposing at least one reference mark onto the electrode.

Scheme 122. the method of scheme 120, wherein connecting at least one lead to the electrode comprises disposing each lead at a respective reference mark.

Scheme 123 the method of scheme 120, wherein connecting at least one lead comprises purging energy storage medium from the current collector.

Scheme 124. the method of scheme 120, wherein connecting at least one lead comprises ultrasonically welding the lead to the current collector.

Scheme 125 the method of scheme 116, wherein fabricating the energy storage cell comprises disposing an isolator between at least two electrodes.

Scheme 126. the method of scheme 125, further comprising aligning each of the electrodes with the separator.

Scheme 127 the method of scheme 116, wherein fabricating the energy storage cell comprises encasing at least two electrodes with a separator disposed therebetween.

Scheme 128. the method of scheme 127, wherein the wrapping comprises rolling the storage unit into a rolled storage unit.

Scheme 129. the method of scheme 116, wherein manufacturing the energy storage unit comprises disposing a wrapper over the storage unit.

Scheme 130. the method of any of schemes 86-129, wherein disposing the energy storage cell comprises bringing a plurality of leads together to provide a terminal.

Scheme 131 the method of scheme 130, wherein said bringing the plurality of leads together comprises aligning the leads together into a set of aligned leads to form the terminal.

Scheme 132 the method of scheme 131, further comprising disposing a wrapper around the set of aligned leads.

Scheme 133 the method of scheme 131, further comprising folding the set of aligned leads.

Scheme 134 the method of scheme 131, further comprising coupling the set of aligned leads to contacts of the housing.

Scheme 135. the method of scheme 134, wherein the coupling comprises soldering the set of aligned wires to the contacts.

Scheme 136 the method of scheme 134, wherein the coupling comprises soldering the set of aligned wires to one of a jumper and a bridge for coupling to contacts of the housing.

Scheme 137 the method of any of schemes 86-115, further comprising electrically coupling at least one of a jumper and a bridge to a contact of the housing.

Scheme 138. the method of scheme 137, further comprising substantially disposing an insulating material over the contacts on the interior of the housing.

Scheme 139 the method of any of schemes 86-138, further comprising hermetically sealing the energy storage unit within the housing.

Scheme 140 the method of any of schemes 86-139, further comprising mating at least one cap with a body to provide the housing.

Scheme 141. the method of scheme 140, wherein the cap comprises one of a concave cap, a convex cap, and a flat cap.

Scheme 142. the method of scheme 140, further comprising removing at least a portion of the multilayer material within the housing to provide the mating.

Scheme 143 the method of scheme 140, wherein hermetically sealing comprises welding the components of the housing together by at least one of pulse welding, laser welding, resistance welding, and TIG welding.

Scheme 144 the method of any one of schemes 86 to 143, further comprising purifying said AES.

Scheme 145. the method of any of schemes 86-144, further comprising disposing a fill port within the housing to provide the filling.

Scheme 146 the method of scheme 145, further comprising sealing the fill port after completing the filling.

Scheme 147. the method of scheme 146, wherein the sealing comprises installing a compatible material into the fill port.

Scheme 148. according to the method of scheme 147, further comprising welding the material mounted to the fill port to the housing.

Scheme 149. the method of scheme 145, wherein the filling comprises disposing the AES over a fill port in the housing.

Scheme 150. according to the method of scheme 149, the filling includes evacuating the fill port in the housing.

Scheme 151. the method of scheme 150, wherein the vacuum is less than about 150 mtorr.

Scheme 152. the method of scheme 150, wherein the vacuum is less than about 40 mtorr.

Scheme 153 the method of scheme 145, wherein the filling is performed in a substantially inert environment.

A method of using a High Temperature Rechargeable Energy Storage Device (HTRESD), the method comprising:

obtaining an HTRESD comprising an Advanced Electrolyte System (AES); and

cycling the HTRESD by alternately charging and discharging the HTRESD at least twice for a duration of 20 hours while maintaining a voltage across the HTRESD such that the HTRESD exhibits an initial peak power density of 0.01W/liter to 150 kW/liter such that the HTRESD is used for at least 20 hours when operating at an ambient temperature in a temperature range of about-40 degrees Celsius to about 210 degrees Celsius.

Scheme 155. the method of scheme 154, wherein the HTRESD is a supercapacitor.

Scheme 156 the method of scheme 154 or 155, wherein the temperature range is about-40 degrees celsius to about 150 degrees celsius.

Scheme 157. the method of scheme 154 or 155, wherein the temperature range is about-40 degrees celsius to about 125 degrees celsius.

Scheme 158 the method of scheme 154 or 155, wherein the temperature range is about 80 degrees celsius to about 210 degrees celsius.

Scheme 159. the method of scheme 154 or 155, wherein the temperature range is about 80 degrees celsius to about 175 degrees celsius.

Scheme 160. the method of scheme 154 or 155, wherein the temperature range is about 80 degrees celsius to about 150 degrees celsius.

Scheme 161. the method of scheme 154 or 155, wherein the temperature range is about-40 degrees celsius to about 80 degrees celsius.

Scheme 162 the method of scheme 154, wherein the HTRESD exhibits an initial peak power density of about 0.01W/liter to about 10 kW/liter.

Scheme 163. the method of any of schemes 154-162, wherein the HTRESD exhibits an initial peak power density of about 0.01W/liter to about 5 kW/liter.

Scheme 164. the method of scheme 163, wherein the HTRESD exhibits an initial peak power density of about 0.01W/liter to about 2 kW/liter.

Scheme 165. a method of using an ultracapacitor, the method comprising:

obtaining the ultracapacitor of any one of aspects 1 to 85, wherein the ultracapacitor exhibits a volumetric leakage current (mA/cubic centimeter) that is less than about 10 mA/cubic centimeter while maintained at a substantially constant temperature in a range between about 100 degrees celsius and about 150 degrees celsius; and

cycling the supercapacitor by alternately charging and discharging the supercapacitor at least twice over a duration of 20 hours while maintaining the voltage across the supercapacitor for 20 hours such that the supercapacitor exhibits an ESR rise of less than about 300% after 20 hours of use while held at a substantially constant temperature in a range between about-40 degrees Celsius to about 210 degrees Celsius.

Scheme 166. the method of scheme 165, wherein the temperature range is between about-40 degrees celsius and about 150 degrees celsius.

Scheme 167. the method of scheme 165, wherein the temperature range is between about-40 degrees celsius and about 125 degrees celsius.

Scheme 168. the method of scheme 165, wherein the temperature range is between about 80 degrees celsius and about 210 degrees celsius.

Scheme 169. the method of scheme 165, wherein the temperature range is between about 80 degrees celsius and about 175 degrees celsius.

Scheme 170. the method of scheme 165, wherein the temperature range is between about 80 degrees celsius and about 150 degrees celsius.

Scheme 171. the method of scheme 165, wherein the temperature range is between about-40 degrees celsius and about 80 degrees celsius.

Scheme 172. a method of providing a high temperature rechargeable energy storage device to a user, the method comprising:

selecting a High Temperature Rechargeable Energy Storage Device (HTRESD) comprising an Advanced Electrolyte System (AES) that exhibits an initial peak power density of between 0.01W/liter and 100 kW/liter and an endurance life of at least 20 hours when exposed to an ambient temperature in a temperature range of about-40 degrees celsius to about 210 degrees celsius; and

delivering the storage device such that the HTRESD is provided to a user.

Scheme 173. a method of providing a high temperature rechargeable energy storage device to a user, the method comprising:

obtaining an ultracapacitor of any one of aspects 1 to 85 that exhibits a volumetric leakage current (mA/cubic centimeter) less than about 10 mA/cubic centimeter while maintained at a substantially constant temperature in a range between about-40 degrees celsius and about 210 degrees celsius; and delivering the storage device such that the HTRESD is provided to a user.

Claims

1. An ultracapacitor, comprising:

hermetically sealing an energy storage cell and an electrolyte composition within a housing, the cell electrically coupled to a positive contact and a negative contact, wherein:

the ultracapacitor is configured to have an operating temperature range of 0 degrees Celsius to 250 degrees Celsius;

the electrolyte composition comprises an ionic liquid mixed with an organic solvent, wherein the ionic liquid comprises 1-butyl-1-methylpyrrolidine

And tetracyanoborate;

wherein the total concentration of impurities in the electrolyte is less than 1000 parts per million; the electrolyte composition has a halide ion content of less than 100 parts per million;

the total concentration of metal species in the electrolyte composition is below 1000 parts per million, wherein the metal species is selected from one or more metals selected from Cd, Co, Cr, Cu, Fe, K, Li, Mo, Na, Ni, Pb, and Zn; and the total water content in the electrolyte composition is less than 100 parts per million.

2. The supercapacitor of claim 1 wherein the electrolyte composition comprises propylene carbonate and 1-butyl-1-methylpyrrolidine

And a mixture of tetracyanoborate salts, said mixture having 37.5% by volume of propylene carbonate.

3. The supercapacitor according to claim 2 wherein the electrolyte composition comprises a first ionic liquid mixed with a second ionic liquid, wherein the first ionic liquid is from 5% to 90% by volume of the composition.

4. The ultracapacitor of claim 3, wherein the first ionic liquid is at least 60 percent of the composition by volume.

5. The supercapacitor according to claim 3 wherein the second ionic liquid is selected from salts of any combination of the following cations and anions, wherein the cations are selected from: 1-butyl-3-methylimidazole

1-ethyl-3-methylimidazole

1-hexyl-3-methylimidazole

1-butyl-1-methylpiperidine

Butyltrimethylammonium, 1-butyl-1-methylpyrrolidine

Trihexyltetradecylphosphonium

And 1-butyl-3-methylimidazole

And the anion is selected from: tetrafluoroborate, bis (trifluoromethylsulfonyl) imide, tetracyanoborate and trifluoromethanesulfonate.

6. The supercapacitor according to any one of the preceding claims wherein the organic solvent is selected from linear sulfones, linear carbonates and acetonitrile.

7. The ultracapacitor of any one of claims 1-5, wherein the operating temperature range comprises 0 degrees Celsius to 210 degrees Celsius.

8. The ultracapacitor of any one of claims 1-5, wherein the electrolyte composition is configured to provide one or more enhanced eutectic properties that alter the freezing point of an advanced electrolyte system.

9. The supercapacitor according to any one of claims 1 to 5 wherein the electrolyte composition is configured such that the operational performance of the supercapacitor is improved relative to the performance of an equivalent device having an electrolyte consisting of only one component of the electrolyte composition, wherein improved operational performance comprises at least one selected from the list of:

the total resistance is reduced; improved long term stability of resistance, increased total capacitance, improved long term stability of capacitance, increased energy density, improved voltage stability, reduced vapor pressure, and wider temperature range performance of individual capacitors.

10. The ultracapacitor of any one of claims 1-5, wherein the ultracapacitor is configured to have:

a volumetric leakage current of less than 1 milliamp/cubic centimeter maintained at a constant temperature; and

a volumetric capacitance in the range of 1 millifarad to 6 farads per cubic centimeter.

11. A method for manufacturing a supercapacitor, comprising the steps of:

disposing an energy storage unit comprising an energy storage medium within a housing;

pre-treating components of the ultracapacitor including at least one of electrodes, separators, leads, assembled energy storage cells, and the housing to reduce moisture therein, wherein the pre-treating includes heating selected components under vacuum in a temperature range of 100 to 150 degrees celsius or 150 to 300 degrees celsius;

purifying an advanced electrolyte system, wherein the advanced electrolyte system comprises an electrolyte composition selected from the group consisting of: (a) a first ionic liquid mixed with a second ionic liquid, (b) an ionic liquid mixed with an organic solvent, and (c) a first ionic liquid mixed with a second ionic liquid and an organic solvent; wherein the total concentration of impurities in the electrolyte is less than 1000 parts per million; the electrolyte composition has a halide ion content of less than 100 parts per million;

the total concentration of metal species in the electrolyte composition is below 1000 parts per million, wherein the metal species is selected from one or more metals selected from Cd, Co, Cr, Cu, Fe, K, Li, Mo, Na, Ni, Pb, and Zn; and a total water content in the electrolyte composition of less than 100 parts per million;

filling the housing with the advanced electrolyte system by disposing the advanced electrolyte system in the housing through a fill port and drawing a vacuum in the housing over the fill port, wherein the vacuum is less than 150 mtorr and the filling is performed in an inert environment; and

the housing is hermetically sealed and the air-tight seal is provided,

wherein the ultracapacitor is manufactured to have an operating temperature range that extends between-40 degrees Celsius or less and 210 degrees Celsius or more.