JP2020523733A - Shape-compatible alkali metal-sulfur battery - Google Patents

Abstract

(A) less than 5% by volume containing from about 30% to about 95% by volume of cathode active material (sulfur-containing material) and an alkali salt dissolved in a solvent and an ion conductive polymer dissolved, dispersed or impregnated in the solvent. -40% by volume of a first electrolyte and about 0.01% by volume) to about 30% by volume) of a conductive additive, wherein the conductive additive comprises a conductive filament. Form a 3D network of electronic conduction paths, whereby the quasi-solid electrode has a conductivity of between about 10 ⁻⁶ S/cm and about 300 S/cm, and (b) an anode, ( c) An alkali metal-sulfur cell comprising an ion conducting membrane or a porous separator disposed between the anode and the quasi-solid cathode, the quasi-solid cathode having a thickness of 200 μm to 100 cm, and An alkali metal-sulfur cell is provided having a cathode active material with an active material mass loading of greater than 10 mg/cm ² .
[Selection diagram] Figure 1(C)

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is US Patent Application Publication No. 15/612,497 filed June 2, 2017 and filed June 2, 2017, which is hereby incorporated by reference. Claims priority to published U.S. Patent Application Publication No. 15/612,537.

The present invention relates generally to the field of alkali metal-sulfur batteries, including rechargeable lithium metal-sulfur batteries, sodium metal-sulfur batteries, lithium ion sulfur batteries and sodium ion sulfur batteries.

Rechargeable lithium-ion (Li-ion) and lithium metal batteries (including Li-sulfur and Li-metal-air batteries) are used in electric vehicles (EV), hybrid electric vehicles (HEV) and portable electronic devices such as laptop computers and mobile phones. Considered a promising power source for phones. Lithium as a metal element has the highest capacity (excluding Li _4.4 Si having a specific capacity of 4,200 mAh/g) as the anode active material (excluding Li _4.4 Si having a specific capacity of 4,200 mAh/g). 3,861 mAh/g). Therefore, Li metal batteries generally have significantly higher energy densities than lithium ion batteries.

Non Historically, rechargeable lithium metal batteries, as a cathode active material is combined with lithium metal _anodes, etc. _{TiS 2, MoS 2, MnO 2} , CoO 2 and _V 2 _{O 5,} having a relatively high specific capacity Prepared using a lithiated compound. When the battery was discharged, lithium ions moved from the lithium metal anode through the electrolyte to the cathode, lithiating the cathode. Unfortunately, upon repeated charge and discharge, lithium metal formed dendrites at the anode, which eventually grew through the separator, causing internal short circuits and explosions. As a result of a series of accidents related to this problem, production of these types of secondary batteries was discontinued in the early 1990s, replacing lithium ion batteries.

In lithium-ion batteries, a sheet or film of pure lithium metal has been replaced by a carbonaceous material as the anode. The carbonaceous material absorbs lithium (eg, by intercalating lithium ions or atoms between the graphene planes) and desorbs lithium ions during the recharge and discharge phases of lithium-ion battery operation, respectively. The carbonaceous material may predominantly include graphite that is capable of intercalating with lithium, and the resulting graphite intercalation compound can be represented as Li _x C ₆ , where x is typically 1 Is less than.

While lithium-ion (Li-ion) batteries are a promising energy storage device for electric powered vehicles, state-of-the-art Li-ion batteries have not yet met the cost and performance goals. Li-ion cells typically use lithium transition metal oxides or phosphates as the positive electrode (cathode) that de-/re-intercalates Li+ at high potential relative to the carbon negative electrode (anode). The specific capacity of lithium transition metal oxide or phosphate based cathode active materials is typically in the range of 140-170 mAh/g. As a result, the specific energy of commercially available Li-ion cells is typically in the range of 120-250 Wh/kg, most typically 150-220 Wh/kg. These specific energy values are 2-3 times lower than required for the wide acceptance of battery-powered electric vehicles.

With the rapid development of hybrid (HEV), plug-in hybrid electric vehicle (HEV), all-battery electric vehicle (EV), significantly higher specific energy, higher energy density, higher rate performance, long cycle life and safety There is an urgent need for anode and cathode materials that provide a rechargeable battery with good performance. One of the most promising energy storage devices is the lithium-sulfur (Li-S) cell. This is because the theoretical capacity of Li is 3,861 mAh/g and the theoretical capacity of S is 1,675 mAh/g. In its simplest form, a Li-S cell consists of elemental sulfur as the positive electrode and lithium as the negative electrode. The lithium-sulfur cell operates with a redox couple represented by the reaction S ₈ +16Li⇔8Li ₂ S, which is close to 2.2 V with respect to Li ⁺ /Li ⁰ . This electrochemical potential is about 2/3 of the potential exhibited by a conventional positive electrode (eg, LiMnO ₄ ) in a conventional lithium-ion battery. However, this drawback is offset by the very high theoretical capacities of both Li and S. Thus, compared to conventional intercalation-based Li-ion batteries, Li-S cells have the potential to offer significantly higher energy density (product of capacity and voltage). Assuming a complete reaction to Li ₂ S, the energy density values can approach 2,500 Wh/kg and 2,800 Wh/L, respectively, based on the total weight or volume of Li and S. When based on total cell weight or volume, the energy densities can reach about 1,000 Wh/kg and 1,100 Wh/L, respectively. However, current Li-sulfur cells reported by industry leaders in sulfur cathode technology have maximum cell specific energies of 250-400 Wh/kg (based on total cell weight or volume) and 500-650 Wh/L. , Which is much lower than possible.

In summary, despite their considerable advantages, Li-S cells have some major technical problems, thus preventing them from widespread commercialization.
(1) Conventional lithium metal cells still have the problems of dendrite formation and related internal short circuits.
(2) Sulfur or a sulfur-containing organic compound has high electrical and ionic insulation. The sulfur must maintain intimate contact with the conductive additive to allow reversible electrochemical reactions at high current densities or charge/discharge rates. Various carbon-sulfur complexes have been utilized for this purpose, but with limited scale of contact area, with limited success. Typical capacities reported are 300-550 mAh/g (based on cathode carbon-sulfur composite weight) at moderate rates.
(3) This cell tends to show significant capacity fade during the discharge-charge cycle. This is mainly due to the high solubility of the lithium polysulfide anion formed in the reaction intermediate both during the discharge process and the charge process in the polar organic solvent used for the electrolyte. During cycling, the lithium polysulfide anions can move through the separator to the Li negative electrode where it is reduced to a solid precipitate (Li ₂ S ₂ and/or Li ₂ S), causing active mass loss. Furthermore, the solid product deposited on the surface of the positive electrode during discharge becomes electrochemically irreversible, which also contributes to active mass loss.
(4) More generally speaking, the major drawback of cells containing cathodes containing elemental sulfur, organic sulfur and carbon-sulfur materials is that soluble sulfides, polysulfides, organosulfates from the cathode to the rest of the cell. It relates to the dissolution and excessive outdiffusion of sulphides, carbon sulphides and/or carbon polysulphides (hereinafter referred to as anionic reduction products). This phenomenon is generally called the shuttle effect. This process gives rise to several problems such as: high self-discharge rate, loss of cathode capacity, corrosion of current collectors and electrical leads leading to loss of electrical contact to active cell components, anode Fouling of the anode surface resulting in malfunction and clogging of the pores of the cell membrane separator resulting in loss of ionic transport and a large increase in internal resistance within the cell.

In response to these challenges, new electrolytes, protective films for lithium anodes and solid electrolytes have been developed. Several interesting cathode developments have recently been reported, including lithium polysulfide. However, their performance has not yet reached that required for practical use.

For example, Ji et al. have reported that cathodes based on nanostructured sulfur/mesoporous carbon materials can significantly overcome these problems, exhibit stable and high reversible capacity, and have excellent rate characteristics and cycling efficiency [Xiulei. Ji, Kyu Tae Lee, & Linda F. Nazar, "A highly ordered nanostructured carbon-sulfur cathode for lithium-sulfur batteries," Nature Materials 8, 500-506 (2009)]. However, the fabrication of the proposed highly ordered mesoporous carbon structure requires a tedious and costly template-assisted process. It is also difficult to load these mesoscale pores with a high proportion of sulfur using physical vapor deposition or solution precipitation.

Zhang et al. (US Patent Publication No. 2014/0234702; August 21, 2014) utilize a chemical reaction method that deposits S particles on the surface of isolated graphene oxide (GO) sheets. However, this method fails to produce a high proportion of S particles (ie, typically less than 66% S in GO-S nanocomposite compositions) on the GO surface. The resulting Li-S cell also has poor rate performance, for example, a specific capacity of 1,100 mAh/g (based on the weight of S) at a rate of 0.02 C drops to <450 mAh/g at a rate of 1.0 C. To be done. Note that the highest achievable specific capacity of 1,100 mAh/g shows a sulfur utilization efficiency of 1,100/1,675=65.7% even at such low charge/discharge rates (0. 02C means complete the charge or discharge process in 1/0.02=50 hours (also 1C=1 hour, 2C=1/2 hours, 3C=1/3 hours, etc.). Moreover, such S-GO nanocomposite cathode-based Li-S cells exhibit very short cycle life, with capacities typically 60% of their original capacity at less than 40 charge/discharge cycles. Fall below. Due to such short cycle life, this Li-S cell is not useful for practical applications. Another chemical reaction method for depositing S particles on graphene oxide surfaces has been disclosed by Wang et al. (US 2013/0171339; Jul. 4, 2013). This Li-S cell still has the same problem.

Liu et al. disclose a solution precipitation method for preparing graphene-sulfur nanocomposites (having sulfur particles adsorbed on GO surfaces) for use as cathode materials in Li-S cells (US Pat. Application Publication No. 2012/0088154; April 12, 2012). The method includes forming a suspension by mixing the S of GO sheets and solvent (CS ₂₎ in. The solvent is then evaporated to obtain a solid nanocomposite, which is then milled to obtain a nanocomposite powder having primary sulfur particles with an average diameter of less than about 50 nm. Unfortunately, this method does not appear to produce S particles below 40 nm. The resulting Li-S cell has a very short cycle life (50% capacity fade after only 50 cycles). Even when these nanocomposite particles are encapsulated in polymers, the Li-S cell retains only less than 80% of its original capacity after 100 cycles. Also, this cell exhibits low rate performance (specific capacity of 1,050 mAh/g (S weight) at a rate of 0.1 C. It drops to <580 mAh/g at a rate of 1.0 C). Again, this suggests that a high proportion of S does not contribute to lithium storage, resulting in low S utilization efficiency.

Despite various proposals for the fabrication of high energy density Li-S cells, charging with improved utilization of electroactive cathode materials (S utilization efficiency) and high capacity over many cycles. There remains a need for cathode materials and manufacturing processes that provide formula Li-S cells.

Most importantly, including lithium metal (pure lithium, high lithium content lithium alloys with other metal elements or lithium-containing compounds with high lithium content; eg >80 wt% or more or preferably >90%. The wt% Li) still provides the highest anode specific capacity compared to virtually all other anode active materials (except pure silicon, but silicon has powdering problems). If the problems associated with dendrites can be addressed, lithium metal will be an ideal anode material in lithium-sulfur secondary batteries.

Sodium metal (Na) and potassium metal (K) have similar chemical properties to Li and are sulfur cathodes in room temperature sodium-sulfur cells (RT Na-S batteries) or potassium-sulfur cells (KS). Face the same problems observed in Li-S cells, such as (i) low active material utilization, (ii) low cycle life, and (iii) low Coulombic efficiency. Again, these drawbacks arise primarily from the insulating properties of S, the dissolution of S and poly Na sulfide or K intermediates in the liquid electrolyte (and the associated shuttle effect), and the large volume changes during charge and discharge.

In most of the published literature reports (scientific papers) and patent literature, scientists or inventors find that the cathode specific capacity is based solely on the weight of sulfur or lithium polysulfide (rather than the total weight of the cathode composite). Unfortunately, these Li-S cells typically have a high proportion of inactive materials (materials that cannot store lithium, such as conductive additives and binders). Note that it is used. For practical purposes, it is more meaningful to use the capacity value based on the weight of the cathode composite.

Low capacity anode or cathode active materials are not the only problems associated with lithium-sulfur or sodium-sulfur batteries. There are significant design and manufacturing issues that the battery industry appears to be unaware of or largely ignores. For example, despite the high weight capacity at the electrode level (based only on the weight of the anode or cathode active material), as frequently claimed in the published and patent literature, these electrodes are unfortunate. However, it is not possible to provide batteries with high capacity at the battery cell or pack level (based on total battery cell weight or pack weight). This is due to the view that the actual active material mass loading of the electrodes is too low in these reports. In most cases, anode active material mass load (surface density) is significantly lower than 15 mg / cm ^2, usually <a 8 mg / cm ² (area density = electrode per cross sectional area in the thickness direction of the electrode Amount of active material). The amount of cathode active material in the cell is typically 1.5 to 2.5 times the amount of anode active material. As a result, the weight ratio of the anode active material (for example, carbon) in the Na ion-sulfur battery cell or the Li ion-sulfur battery cell is typically 15% to 20%, and the weight ratio of the cathode active material is 20% to 35% (usually <30%). The composite weight fraction of cathode active material and anode active material is typically 35% to 50% of the cell weight.

The low active material mass loading is primarily due to the inability to obtain relatively thick electrodes (thickness greater than 100-200 μm) using conventional slurry coating procedures. This is not as easy a task as one might think, and in reality the electrode thickness is not a design parameter that can be changed arbitrarily and freely to optimize cell performance. Conversely, thicker samples tend to be very brittle or have poor structural integrity and also require the use of large amounts of binder resin. Due to the low melting point and soft nature of sulfur, it is virtually impossible to form sulfur cathodes thicker than 100 μm. Moreover, in practical battery manufacturing facilities, coated electrodes thicker than 150 μm require a heating zone 100 meters long to completely dry the coated slurry. This significantly increases equipment costs and reduces manufacturing throughput. Due to the low areal density and low volume density (related to thin electrodes and low packing density), the battery cell has relatively low volume capacity and low volume energy density.

With the increasing demand for more compact and portable energy storage systems, there is a strong interest in increasing battery volume utilization. In order to achieve improved cell volume capacity and energy density, new electrode materials and designs that enable high volume capacity and high mass loading are essential.

Therefore, it is an object of the present invention to provide a rechargeable alkali metal-sulfur based rational material and battery design that overcomes or significantly reduces the following problems commonly associated with conventional Li-S and Na-S cells. To provide a cell: (a) dendrite formation (internal short circuit), (b) very low electrical and ionic conductivity of sulfur. It requires a large proportion (typically 30-55%) of inert conductive fillers and has a significant proportion of inaccessible or unreachable sulfur or alkali metal polysulfides, ( c) Dissolution of S and alkali metal polysulfides in the electrolyte and migration of polysulfides from the cathode to the anode, which reacts irreversibly with Li or Na metal at the anode. This results in active material loss and capacity decay (shuttle effect), (d) short cycle life, and (e) low active mass loading on both anode and cathode.

A specific object of the present invention is to provide a rechargeable alkali metal-sulfur battery (eg predominantly Li-S and room temperature Na-S battery) that exhibits very high specific energy or specific energy density. One particular technical goal of the present invention is (all based on total cell weight) greater than 400 Wh/Kg, preferably greater than 500 Wh/Kg, more preferably greater than 600 Wh/Kg, most preferably 700 Wh/kg. To provide an alkali metal-sulfur or alkali ion-sulfur cell having a greater cell specific energy. Preferably, the volumetric energy density is greater than 600 Wh/L, more preferably greater than 800 Wh/L, most preferably greater than 1,000 Wh/L.

Another object of the present invention is greater than 1,200 mAh/g based on the weight of sulfur or the cathode composite weight (including the combined weight of sulfur, conductive additive or substrate and binder, (Excluding the weight of the cathode current collector) to provide an alkali metal-sulfur cell that exhibits a high cathode specific capacity of greater than 1,000 mAh/g. Preferably, the specific capacity is greater than 1,400 mAh/g based on sulfur weight alone or greater than 1,200 mAh/g based on the cathode composite weight. This entails a high specific energy, good resistance to dendrite formation and a long and stable cycle life.

As electronic devices become more compact and electric vehicles (EVs) become lighter, they are conformable, high energy density, that is conformable to fit into any irregular shape or confined space within the device or vehicle. The need for batteries is imminent. Allows devices to be made more compact by mounting batteries in spaces that would otherwise be empty (unused or "wasted") spaces (eg, car doors or parts of rooftops) Or, more power can be stored in the EV. In order to make a cell conformable, the electrodes must be deformable, flexible, and conformable.

Therefore, the need for lithium and sodium batteries with high active material mass loading (high areal density), high electrode thickness or volume without compromising conductivity, high rate performance, high power density and high energy density is clear. , Urgent. These batteries must be manufactured environmentally friendly. Furthermore, the battery must be conformable.

The present invention provides a lithium-sulfur or sodium-sulfur battery with high active material mass loading, extremely low overhead weight and volume (relative to active material mass and volume), high capacity and unprecedented high energy and power densities. A method of manufacturing is provided. The Li-S or Na-S battery may be a primary battery (non-rechargeable) or a secondary battery (rechargeable), and is a rechargeable lithium metal-sulfur battery or sodium metal-sulfur battery (lithium or sodium metal anode). And a lithium ion sulfur battery or a sodium ion sulfur battery (eg, having a first lithium intercalation compound as the anode active material).

In certain embodiments, the invention provides (a) about 30% to about 95% by volume of a sulfur-containing cathode active material (preferably sulfur, metal-sulfur compounds, sulfur-carbon composites, sulfur-graphene composites). A sulfur-graphite composite, an organic sulfur compound, a sulfur-polymer composite or combinations thereof) and an alkali salt dissolved in a solvent, the first about 5% to about 40% by volume. A quasi-solid cathode containing an electrolyte, an ion-conducting polymer dissolved, dispersed or impregnated in the solvent, and about 0.01% to about 30% by volume of a conductive additive, the conductive solid filament containing a conductive filament. A conductive additive that forms a 3D network of electronic conduction pathways, whereby the quasi-solid electrode has a quasi-solid cathode having a conductivity of from about 10 ⁻⁶ S/cm to about 300 S/cm; ) An alkali-sulfur cell comprising an anode and (c) an ion conducting membrane or a porous separator disposed between the anode and the quasi-solid cathode, wherein the quasi-solid cathode has a thickness of 200 μm or more. An alkali-sulfur cell having. Preferably, the quasi-solid cathode is 10 mg/cm ² or more, preferably 15 mg/cm ² or more, more preferably 25 mg/cm ² or more, more preferably 35 mg/cm ² or more, even more preferably 45 mg/cm ² or more, Most preferably it contains a cathode active material mass loading of greater than 65 mg/cm ² .

In this cell, the anode comprises from about 1.0% to about 95% by volume of anode active material and from about 5% to about 40% by volume of a second electrolyte containing an alkali salt dissolved in a solvent. A semi-solid anode comprising an ion conducting polymer dissolved, dispersed or impregnated in the solvent and from about 0.01% to about 30% by volume of a conductive additive, said conductive solid containing a conductive filament. The conductive additive forms a 3D network of electronic conduction paths, whereby the quasi-solid electrode has a conductivity of about 10 ⁻⁶ S/cm to about 300 S/cm, and the quasi-solid anode has a conductivity of 200 μm or more. A quasi-solid anode having a thickness of Preferably, the quasi-solid anode is 10 mg/cm ² or more, preferably 15 mg/cm ² or more, more preferably 25 mg/cm ² or more, more preferably 35 mg/cm ² or more, even more preferably 45 mg/cm ² or more, Most preferably it contains an anode active material mass loading of greater than 65 mg/cm ² . The first electrolyte can be the same or different in composition and structure as the second electrolyte.

In certain embodiments, the invention provides (A) from about 1.0% to about 95% by volume of an anode active material and from about 5% to about 40% by volume containing an alkali salt dissolved in a solvent. A quasi-solid anode containing an electrolyte, an ion-conducting polymer dissolved, dispersed or impregnated in this solvent, and about 0.01% to about 30% by volume of a conductive additive, the conductive solid filament containing a conductive filament. The conductive additive forming a 3D network of electronic conduction paths, whereby the quasi-solid electrode has a conductivity of about 10 ⁻⁶ S/cm to about 300 S/cm; ) Contains a sulfur-containing cathode active material selected from sulfur, metal-sulfur compounds, sulfur-carbon composites, sulfur-graphene composites, sulfur-graphite composites, organic sulfur compounds, sulfur-polymer composites or combinations thereof. And a (C) quasi-solid anode and an ion conductive membrane or a porous separator disposed between the cathode and the alkali-sulfur cell, wherein the quasi-solid anode and the cathode each have a thickness of 200 μm or more. An alkali-sulfur cell having a thickness is provided.

The quasi-solid polymer electrodes of the present invention enable deformable, flexible, conformable, conformable batteries.

The present invention also provides a method for preparing an alkali-sulfur cell having a quasi-solid electrode, which comprises (a) a certain amount of an active material (anode active material or cathode active material) and an alkali salt dissolved in a solvent. A step of forming a deformable and conductive electrode material by combining a certain amount of an electrolyte, an ion conductive polymer dissolved, dispersed or impregnated in this solvent, and a conductive additive, the conductive filament The conductive additive containing is a step of forming a 3D network of electron conduction paths, and (b) a step of forming an electrode material into a quasi-solid electrode, wherein the electrode is 10 ⁻⁶ S/cm or more ( Preferably 10 ⁻⁵ S/cm or more, more preferably 10 ⁻³ S/cm or more, further preferably 10 ⁻² S/cm or more, even more preferably and typically 10 ⁻¹ S/cm or more, More typically and preferably 1 S/cm or more, even more typically and preferably 10 S/cm or more, up to 300 S/cm), so that the 3D network of electronic conduction paths is maintained. Comprising transforming the electrode material into an electrode shape without interruption, (c) forming a second electrode (the second electrode may also be a quasi-solid electrode), and (d) quasi- Forming a alkali-sulfur cell by combining a solid electrode and a second electrode with an ion-conducting separator disposed between the two electrodes.

In some embodiments, the electrolyte (including the first electrolyte or the second electrolyte) is poly(ethylene oxide) (PEO, less than 1×10 ⁶ g/mol, preferably 0.5×10 ⁶ g/mol. Less than), polypropylene oxide (PPO), poly(acrylonitrile) (PAN), poly(methylmethacrylate) (PMMA), poly(vinylidene fluoride) (PVDF), polybis-methoxyethoxyethoxide-phosphazene, poly Contains a lithium ion conducting or sodium ion conducting polymer selected from vinyl chloride, polydimethylsiloxane, poly(vinylidene fluoride)-hexafluoropropylene (PVDF-HFP), their sulfonated derivatives, sulfonated polymers or combinations thereof To do. Here, sulfonation has been found to improve the lithium ion conductivity of the polymer. Molecular weights of PEO higher than 1×10 ⁶ g/mol typically render the PEO insoluble or non-dispersible in the solvent.

Typically and preferably, the ion conducting polymer does not form a matrix (continuous phase) within the electrode.

The ion conductive polymer is poly(perfluorosulfonic acid), sulfonated polytetrafluoroethylene, sulfonated perfluoroalkoxy derivative of polytetrafluoroethylene, sulfonated polysulfone, sulfonated poly(ether ketone), sulfonated poly(ether ether). Ketone), sulfonated polystyrene, sulfonated polyimide, sulfonated styrene-butadiene copolymer, sulfonated polychloro-trifluoroethylene (PCTFE), sulfonated perfluoroethylene-propylene copolymer (FEP), sulfonated ethylene-chloro. Trifluoroethylene copolymer (ECTFE), Sulfonated polyvinylidene fluoride (PVDF), Sulfonated copolymer of polyvinylidene fluoride and hexafluoropropene and tetrafluoroethylene, Sulfonated copolymer of ethylene and tetrafluoroethylene (ETFE), sulfonated polybenzimidazole (PBI), their chemical derivatives, copolymers, blends and combinations thereof. Surprisingly, the inventors have observed that these sulfonated polymers have both lithium and sodium ion conductivity.

A "filament" is a solid material body having a largest dimension (eg length) and a smallest dimension (eg diameter or thickness), the ratio of the largest dimension to the smallest dimension being greater than 3, preferably greater than 10. Is larger, more preferably larger than 100. Typically, this is a wire-like, fiber-like, needle-like, rod-like, platelet-like, sheet-like, ribbon-like or disc-like object, just to name a few. In certain embodiments, the conductive filaments are carbon fibers, graphite fibers, carbon nanofibers, graphite nanofibers, carbon nanotubes, needle cokes, carbon whiskers, conductive polymer fibers, conductive material coated fibers, metal nanowires, metal fibers. , Metal wires, graphene sheets, expanded graphite platelets, combinations thereof or combinations thereof with non-filamentary conductive particles.

In certain embodiments, the electrodes maintain a conductivity of 10 ⁻⁵ S/cm to about 100 S/cm.

In certain embodiments, the deformable electrode material has an apparent viscosity of greater than or equal to about 10,000 Pa·s measured at an apparent shear rate of 1,000 s ⁻¹ . In certain embodiments, the deformable electrode material has an apparent viscosity of greater than or equal to about 100,000 Pa·s at an apparent shear rate of 1,000 s ⁻¹ .

In this method, the amount of active material is typically about 20% to about 95% by volume of the electrode material, more typically about 35% to about 85% by volume of the electrode material, most typically. Is about 50% to about 75% by volume of the electrode material.

Preferably, the step of combining the active material, the conductive additive and the electrolyte, including dissolving the lithium or sodium salt in a liquid solvent, follows a particular sequence. This step involves first dispersing the conductive filaments in a liquid solvent to produce a homogeneous suspension, then adding the active material to the suspension, dissolving the lithium or sodium salt in the liquid solvent, Dissolving or dispersing the conductive polymer in a solvent. In other words, the conductive filaments must first be uniformly dispersed in the liquid solvent before adding the active material and other components such as the ion-conducting polymer and before dissolving the lithium or sodium salt in the solvent. .. This order is essential to achieve percolation of the conducting filaments to form a 3D network of electronic conduction paths with a lower conducting filament volume fraction (lower threshold volume fraction). If such an order is not followed, percolation of the conducting filaments may not occur or may only occur when a very large proportion of conducting filaments (eg greater than 10% by volume) is added. Such extremely large proportions of conductive filaments reduce the fraction of active material and thus the energy density of the cell.

In certain embodiments, combining the electrode materials to form a quasi-solid electrode comprises dissolving a lithium salt (or sodium salt) and an ion-conducting polymer in a liquid solvent to produce a first salt concentration and a first polymer concentration. Forming a polymer electrolyte having a salt concentration and then removing a portion of the liquid solvent to increase the salt concentration to obtain a quasi-solid polymer electrolyte having a second salt concentration and a second polymer concentration, The second salt concentration and the second polymer concentration are higher than the first concentration, preferably higher than 2.5M of the complex salt and polymer (more preferably 3.0M to 14M). The resulting electrolyte is supersaturated without precipitation or crystallization of salts and/or polymers from the electrolyte.

The step of removing a portion of the solvent may be carried out so as not to cause salt or polymer precipitation or crystallization and the electrolyte to be supersaturated. In certain preferred embodiments, the liquid solvent contains a mixture of at least a first liquid solvent and a second liquid solvent, and the first liquid solvent is more volatile than the second liquid solvent and the liquid The step of removing a portion of the solvent includes partially or completely removing the first liquid solvent. The resulting electrolyte is supersaturated without precipitation or crystallization of salts and/or polymers from the electrolyte.

There is no limitation on the type of anode active material that can be used in the practice of the present invention. In one particular preferred embodiment, the alkali metal cell is a lithium metal battery, a lithium ion battery or a lithium ion capacitor, and the anode active material is (a) particles of lithium metal or a lithium metal alloy and (b) natural. Graphite particles, artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles (including soft carbon and hard carbon), needle coke, carbon nanotubes, carbon nanofibers, carbon fibers and graphite fibers, and (c) silicon (Si ), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), nickel (Ni), cobalt (Co), manganese (Mn). ), titanium (Ti), iron (Fe) and cadmium (Cd), and (d) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al or an alloy or intermetallic compound of Cd with another element. And (e) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ni, Co, Ti, Mn, and an alloy or intermetallic compound that is stoichiometric or non-stoichiometric. Or oxides, carbides, nitrides, sulfides, phosphides, selenides and tellurides of Cd and their mixtures or composites, (f) prelithiated versions thereof, and (g) prelithiation. Selected graphene sheets and combinations thereof.

In certain embodiments, the alkali metal-sulfur cell is a sodium metal-sulfur cell or a sodium ion sulfur cell and the active material is petroleum coke, amorphous carbon, activated carbon, hard carbon (carbon that is difficult to graphitize). ), soft carbon (carbon that can be easily graphitized), template carbon, hollow carbon nanowires, hollow carbon spheres, titanates, NaTi ₂ (PO ₄ ) ₃ , Na ₂ Ti ₃ O ₇ , Na ₂ C ₈ H ₄ O. ₄ , Na ₂ TP, Na _x TiO ₂ (x=0.2 to 1.0), Na ₂ C ₈ H ₄ O ₄ , carboxylic acid-based material, C ₈ H ₄ Na ₂ O ₄ , C ₈ H ₆ O _4, is selected from _{C 8 H 5 NaO 4, C} 8 Na 2 F 4 O 4, C 10 H 2 Na 4 O 8, C 14 H 4 O 6, C 14 H 4 Na 4 O 8 , or a combination thereof Is an anode active material containing a sodium intercalation compound.

In certain embodiments, the alkali metal-sulfur cell is a sodium metal-sulfur cell or sodium ion sulfur cell, and the active material is (a) particles of sodium metal or sodium metal alloy and (b) natural graphite particles. , Artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle cokes, carbon nanotubes, carbon nanofibers, carbon fibers and graphite fibers, and (c) sodium-doped silicon (Si), germanium (Ge) , Tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), titanium (Ti), cobalt (Co), nickel (Ni), manganese (Mn). , Cadmium (Cd) and mixtures thereof, and (d) sodium-containing alloys or intermetallics of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Co, Ni, Mn, Cd and mixtures thereof. Compounds and (e) sodium-containing oxides, carbides, and nitrides of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ti, Co, Ni, Mn, Cd, and mixtures or composites thereof. Selected from the group consisting of, sulfides, phosphides, selenides, tellurides or antimonides, (f) sodium salts, (g) graphene sheets preloaded with sodium ions, and combinations thereof. It is an active material.

The electrolyte is water, an organic liquid, an ionic liquid (an ionic salt having a melting point lower than 100° C., preferably lower than room temperature of 25° C.) or a mixture of an ionic liquid and an organic liquid at a ratio of 1/100 to 100/1. Can be included in a ratio. Organic liquids are preferred, but ionic liquids are preferred. The electrolyte typically and preferably contains a high solute concentration (complex concentration of lithium/sodium salt and polymer) that saturates or supersaturates the solute at the resulting electrode (anode or cathode). Such electrolytes are essentially polymeric electrolytes that behave like solids that are deformable or adaptable. This is fundamentally different from liquid electrolytes or polymer gel electrolytes.

In a preferred embodiment, the quasi-solid electrode has a thickness of 200 μm to 1 cm, preferably 300 μm to 0.5 cm (5 mm), more preferably 400 μm to 3 mm, and most preferably 500 μm to 2.5 mm (2,500 μm). .. When the active material is an anode active material, the anode active material has a mass loading of 25 mg/cm ² or more (preferably 30 mg/cm ² or more, more preferably 35 mg/cm ² or more) and/or the battery. It makes up at least 25% by weight or volume% of the entire cell (preferably at least 30% by weight or volume%, more preferably at least 35% by weight or volume %). When the active material is a cathode active material, the cathode active material is preferably 20 mg/cm ² or more (preferably 25 mg/cm ² or more, more preferably 30 mg/cm ² or more, most preferably 40 mg/cm ² in the cathode. ² or more) and/or occupy at least 45 wt% or volume% (preferably at least 50 wt% or volume %, more preferably at least 55 wt% or volume %) of the entire battery cell.

The above requirements for electrode thickness, areal mass loading of the anode active material or mass fraction of the whole battery cell or areal mass loading of the cathode active material or mass fraction of the whole battery cell are conventional slurry coating and drying. It was not possible with conventional lithium or sodium batteries using the process.

In some embodiments, the anode active material is pure graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, graphene hydride, graphene nitride, boron doped. A pre-lithiated version of a graphene sheet selected from graphene, nitrogen-doped graphene, chemically functionalized graphene, physically or chemically activated or etched versions thereof, or combinations thereof. Surprisingly, without prelithiation, the resulting lithium battery cells do not exhibit a satisfactory cycle life (ie, the capacity drops rapidly).

The lithium metal battery, the cathode active material, structure 15 mg / cm ² greater (preferably 25 mg / cm ^2, more preferably above 35 mg / cm ^2, most preferably above 50 mg / cm ² than) an electrode active material loading of And/or the electrode has a thickness of 300 μm or more (preferably 400 μm or more, more preferably 500 μm or more, which can be up to 100 cm or more than 100 cm). There is no theoretical limit to the electrode thickness of the alkali metal battery according to the present invention.

FIG. 1A shows an anode current collector, one or two anode active material layers (for example, a thin Si coating layer) coated on two main surfaces of the anode current collector, a porous separator and an electrolyte. FIG. 1 is a schematic diagram of a prior art lithium-ion battery cell composed of, and one or two cathode electrode layers (eg, a sulfur layer) and a cathode current collector. In FIG. 1B, the electrode layer includes discrete particles of the active material (eg, graphite or tin oxide particles in the anode layer or LiCoO ₂ in the cathode layer), a conductive additive (not shown), and a resin. 1 is a schematic diagram of a prior art lithium-ion battery composed of a binder (not shown). FIG. 1(C) shows a quasi-solid anode (comprising anode active material particles and conductive filaments directly mixed or dispersed in an electrolyte), a porous separator, and a quasi-solid cathode (directly mixed or dispersed in an electrolyte). FIG. 2 is a schematic view of a lithium ion battery cell according to the present invention including a cathode active material particle and a conductive filament). In this embodiment, no resin binder is needed. FIG. 1(D) shows an anode (containing a lithium metal layer deposited on a Cu foil surface), a porous separator, a quasi-solid cathode (cathode active material particles directly mixed or dispersed in an electrolyte and conductivity). And (comprising a filament). In this embodiment, no resin binder is needed. FIG. 2A is a schematic diagram of a dense and highly ordered structure of a solid electrolyte. FIG. 2(B) is a schematic diagram of a completely amorphous liquid electrolyte with a large proportion of free volume to which cations (eg, Na ⁺ ) can easily migrate. FIG. 2(C) is a disordered or amorphous quasi-solid electrolyte containing solvent molecules that separate salt species to create an amorphous zone where free (non-clustered) cations can easily migrate. It is a schematic diagram of a structure. Also, the ion-conducting polymer is in a supersaturated state that remains substantially amorphous. FIG. 3A is a Na ⁺ ion transport number of an electrolyte (for example, (PEO+NaTFSI salt) in a (DOL+DME) solvent) with respect to a sodium salt molecule ratio x. FIG. 3(B) is the Na ⁺ ion transport number of the electrolyte (for example, (PPO+NaTFSI salt) in the solvent of (EMImTFSI+DOL)) with respect to the sodium salt molecule ratio x. FIG. 4 is for producing exfoliated graphite, expanded graphite flakes (thickness >100 nm) and graphene sheets (thickness <100 nm, more typically <10 nm and can be as thin as 0.34 nm). 1 is a schematic diagram of a commonly used method. FIG. 5(A) is the conductivity (percolation behavior) of the conductive filament in the quasi-solid polymer electrode plotted as a function of the volume fraction of the conductive filament (carbon nanofiber). FIG. 5(B) is the conductivity (percolation behavior) of the conductive filament in the quasi-solid polymer electrode plotted as a function of the volume fraction of the conductive filament (reduced graphene oxide sheet). FIG. 6(A) is a Ragone plot (weight output density vs. energy density) of a Li-S cell containing S/CB composite particles as a cathode active material and carbon nanofibers as a conductive filament. Three of the four data curves are for cells prepared according to embodiments of the present invention, the other one is from conventional slurry coating (roll coating) of the electrodes. FIG. 6B is a cycle behavior of a conventional Li-S cell and a Li-S cell including a quasi-solid polymer electrolyte and a quasi-solid polymer cathode. FIG. 7(A) is a Ragone plot (weight output) of a Li-S cell containing graphene-supported S particles (S electrochemically deposited on the graphene surface) as a cathode active material and RGO as a conductive filament. Density versus energy density). Three of the four data curves are for cells prepared according to embodiments of the present invention, the other one is from conventional slurry coating (roll coating) of the electrodes. FIG. 7B is a cycle behavior of a conventional Li-S cell and a Li-S cell including a quasi-solid polymer electrolyte and a quasi-solid polymer cathode.

The present invention is directed to a lithium-sulfur battery or a sodium-sulfur battery, which has not been realized hitherto and has a very high volume energy density. The battery may be a primary battery, but may be a lithium ion sulfur battery, a lithium metal-sulfur secondary battery (e.g. using lithium metal as the anode active material), a sodium ion sulfur battery, a sodium metal-sulfur battery (e.g. It is preferable that the secondary battery is selected from the group consisting of sodium metal used as an anode active material and sulfur supported on carbon used as a cathode active material. Batteries are based on quasi-solid polymer electrolytes containing polymers and lithium or sodium salts dissolved in water, organic solvents, ionic liquids or mixtures of organic and ionic liquids. Preferably, the electrolyte is a "quasi-solid polymer electrolyte" containing a high concentration of solute (complex of lithium salt or sodium salt and polymer) in the solvent, behaving like a solid, but with the desired amount of conductive material. The active filaments and active material remain deformable when added to the electrolyte (hence the term "deformable quasi-solid polymer electrode"). The electrolyte is neither a liquid electrolyte nor a solid electrolyte. The shape of the lithium battery can be cylindrical, square, button-shaped, etc., and can be rough or irregular. The present invention is not limited to any battery shape or configuration.

As shown in FIG. 1A, prior art lithium or sodium battery cells, including Li-S or room temperature Na-S cells, typically have an anode current collector (eg, Cu foil) and an anode. Electrode or anode active material layer (eg, Li metal foil, sodium foil or prelithiated Si deposited on one or two sides of Cu foil), porous separator and/or electrolyte component, and cathode electrode or cathode It is composed of an active material layer (or two cathode active material layers coated on two sides of an Al foil) and a cathode current collector (for example, Al foil).

In a more commonly used prior art cell configuration (FIG. 1(B)), the anode layer comprises an anode active material (eg, graphite, hard carbon or Si) and a conductive additive (eg, carbon black particles). ) And a resin binder (for example, SBR or PVDF). The cathode layer includes a cathode active material (for example, LFP particles in a Li ion cell or polylithium sulfide/carbon composite particles in a Li-S cell), a conductive additive (for example, carbon black particles), and a resin binder ( For example, PVDF) and particles. Both the anode and cathode layers are typically 100-200 [mu]m thick so as to probably produce a sufficient amount of current per unit electrode area. This thickness range is considered to be an industry accepted constraint that battery designers typically work with. This thickness constraint is due to several reasons: (a) existing battery electrode coating machines are not equipped to coat very thin or very thick electrode layers. , (B) thinner layers are preferred in view of shortening the lithium ion diffusion path length, but if the layers are too thin (eg less than 100 μm) they do not contain a sufficient amount of active lithium storage material (and therefore Sufficient current output), (c) thicker electrodes are susceptible to delamination or cracking during drying or handling after roll coating, and (d) minimal overhead weight and maximum lithium storage performance and thus maximization. In order to obtain a defined energy density (Wk/kg or Wh/L of cell), all non-active material layers (eg current collector and separator) in the battery cell must be minimized.

In less commonly used cell configurations, an anode active material (eg, Si coating) or cathode active material is deposited on a current collector, such as a copper or Al foil, as shown in FIG. It is deposited directly in the form of a thin film. However, such thin film structures, which have very small thickness dimensions (typically much less than 500 nm, and often less than 100 nm if needed), have It suggests that only small amounts of active material can be incorporated into the electrodes (assuming the same surface area), resulting in low total lithium storage capacity and low lithium storage capacity per unit electrode surface area. Such a thin film should have a thickness of less than 100 nm in order to be more resistant to cycling-induced cracking (for the anode) or to facilitate full utilization of the cathode active material. Such constraints further reduce the total lithium storage capacity and the sodium or lithium storage capacity per unit electrode surface area. Such thin film batteries have a very limited range of applications.

On the anode side, Si layers thicker than 100 nm have been found to have low cracking resistance during battery charge/discharge cycles. The Si layer is crushed in just a few cycles. On the cathode side, a sputtered layer of lithium metal oxide thicker than 100 nm does not allow lithium ions to fully penetrate and reach the entire cathode layer, resulting in low cathode active material utilization. The desired electrode thickness is at least 100 μm and the individual active material coatings or particles desirably have dimensions less than 100 nm. Therefore, these thin film electrodes (having a thickness of <100 nm) deposited directly on the current collector are three orders of magnitude less than the required thickness. As a further problem, cathode active materials are not all conductive to both electrons and lithium ions. A large layer thickness indicates a very high internal resistance and low active material utilization. Sodium batteries have similar problems.

That is, in terms of material type, size, electrode layer thickness and active material mass loading, there are several conflicting factors that must be considered simultaneously when designing and selecting a cathode or anode active material. So far, no effective solution has been provided by any prior art teaching to these often conflicting problems. As disclosed herein, the inventors have plagued battery designers and also electrochemists for over thirty years by developing new methods of making lithium or sodium batteries. Solved these challenges.

Prior art lithium battery cells are typically manufactured by a method that includes the following steps: (a) The first step is the anode active material (eg, Si nanoparticles or mesocarbon microbeads, MCMB). , Particles of a conductive filler (eg, graphite flakes) and a resin binder (eg, PVDF) in a solvent (eg, NMP) to form an anode slurry. Separately, particles of a cathode active material (eg, LFP particles), a conductive filler (eg, acetylene black) and a resin binder (eg, PVDF) are mixed and dispersed in a solvent (eg, NMP). Forming a cathode slurry. (B) The second step is to dry the coated layer by coating the anode slurry on one or both major surfaces of the anode current collector (eg Cu foil) and evaporating the solvent (eg NMP). To form a dry anode electrode coated on a Cu foil. Similarly, the cathode slurry is coated and dried to form a coated dry cathode electrode on the Al foil. In an actual manufacturing situation, slurry coating is usually performed by a roll-to-roll method, and (c) the third step is to laminate an anode/Cu foil sheet, a porous separator layer and a cathode/Al foil sheet together. Forming a three-layer or five-layer assembly, which is cut or slit into desired sizes and laminated to form a rectangular structure (as an example of a shape) or rolled into a cylindrical cell structure. Including doing. (D) The rectangular or cylindrical laminated structure is then housed in an aluminum plastic laminated envelope or steel casing. (E) Next, a liquid electrolyte is injected into the laminated structure to manufacture a lithium battery cell.

There are several significant problems associated with this method and the resulting lithium battery cell.
1) It is very difficult to manufacture an electrode layer (anode layer or cathode layer) thicker than 200 μm. There are several reasons. Electrodes 100-200 μm thick typically require a heating zone of 30-50 meters in length in a slurry coating facility, which is too time consuming, energy consuming and cost effective. Absent. For some electrode active materials such as metal oxide particles, electrodes with good structural integrity thicker than 100 μm have not been able to be continuously manufactured in a real manufacturing environment. The resulting electrode is very fragile and brittle. Thicker electrodes are more prone to delamination and cracking.
2) In the conventional method as shown in FIG. 1(A), the actual mass loading of the electrodes and the apparent density of the active material are too low to achieve the weight energy density of more than 200 Wh/kg. Often, even for relatively large graphite particles, the anode active material mass loading (area density) of the electrode is much lower than 25 mg/cm ² , and the apparent bulk or tap density of the active material is typically 1. It is less than 2 g/cm ³ . The cathode active material mass loading (area density) of the electrodes is significantly below 45 mg/cm ^{2 for} lithium metal oxide type inorganic materials and below 15 mg/cm ² for organic or polymeric materials. Moreover, there are numerous other non-active materials (eg, conductive additives and resin binders) that add additional weight and volume to the electrode without contributing to battery capacity. These low areal and low volume densities result in relatively low gravimetric energy densities and low volumetric energy densities.
3) In the conventional method, it is necessary to disperse the electrode active material (anode active material and cathode active material) in a liquid solvent (for example, NMP) to form a slurry. It must be removed and the electrode layer dried. After stacking the anode and cathode layers with the separator layer and packaging in a housing to form a battery cell, a liquid electrolyte is injected into the cell. In practice, the two electrodes are wetted, then the electrodes are dried and finally wetted again. Such a dry-wet-dry-wet method is not a good process.
4) Current lithium ion batteries still have problems of relatively low weight energy density and low volume energy density. Commercially available lithium ion batteries exhibit a gravimetric energy density of about 150-220 Wh/kg and a volume energy density of 450-600 Wh/L.

In the literature, energy density data reported based on active material weight alone or electrode weight cannot directly derive the energy density of a practical battery cell or device. The "overhead weight", ie the weight of other device components (binders, conductive additives, current collectors, separators, electrolytes and packaging) must also be taken into account. In conventional manufacturing processes, the weight ratio of anode active material (eg, graphite or carbon) in a lithium-ion battery is typically 12% to 17%, and the weight ratio of cathode active material is 20% to 35%. % (For inorganics such as LiMn ₂ O ₄ ) or 7-15% (for organic or polymeric cathode materials).

The present invention provides lithium sulfur batteries or room temperature sodium sulfur battery cells having high electrode thickness, high active material mass loading, low overhead weight and volume, high capacity and high energy density. In certain embodiments, the invention provides (a) about 30% to about 95% by volume of a cathode active material (sulfur, metal-sulfur compound, sulfur-carbon composite, sulfur-graphene composite, sulfur-graphite composite). An organic sulfur compound, a sulfur-polymer composite or a combination thereof), and about 5% to about 40% by volume of an alkali salt dissolved in a solvent. A quasi-solid polymer cathode comprising a first electrolyte, an ion-conducting polymer dissolved, dispersed or impregnated in the solvent, and from about 0.01% to about 30% by volume of a conductive additive, wherein The conductive additive containing the conductive filaments forms a 3D network of electronic conduction paths, which allows the quasi-solid electrode to have a conductivity of about 10 ⁻⁶ S/cm to about 300 S/cm (which can be higher). A quasi-solid polymer cathode having an index, (b) an anode (which may be a conventional anode or a quasi-solid polymer electrode), and (c) an ion-conducting membrane or porosity disposed between the anode and the quasi-solid cathode. And a semi-solid cathode, wherein the quasi-solid cathode has a thickness of 200 μm or more. Preferably, the quasi-solid polymer cathode is 10 mg/cm ² or more, preferably 15 mg/cm ² or more, more preferably 25 mg/cm ² or more, more preferably 35 mg/cm ² or more, even more preferably 45 mg/cm ² or more. Most preferably contains a cathode active material mass loading of greater than 65 mg/cm ² .

In this cell, the anode comprises about 30% to about 95% by volume of anode active material, about 5% to about 40% by volume of a second electrolyte containing an alkali salt dissolved in a solvent, and the solvent. A quasi-solid polymer anode comprising an ion-conducting polymer dissolved, dispersed or impregnated in a sol, and from about 0.01% to about 30% by volume of a conductive additive, the conductive solid containing a conductive filament. The additive forms a 3D network of electronic conduction pathways, whereby the quasi-solid electrode has a conductivity of about 10 ⁻⁶ S/cm to about 300 S/cm, and the quasi-solid anode has a conductivity of 200 μm or more. It may include a quasi-solid polymer anode having a thickness. Preferably, the quasi-solid anode is 10 mg/cm ² or more, preferably 15 mg/cm ² or more, more preferably 25 mg/cm ² or more, more preferably 35 mg/cm ² or more, even more preferably 45 mg/cm ² or more, Most preferably it contains an anode active material mass loading of greater than 65 mg/cm ² . The first electrolyte can be the same or different in composition and structure as the second electrolyte.

In some embodiments, the alkali metal cell comprises a quasi-solid polymer anode, but comprises a conventional cathode. However, preferably the cathode is a quasi-solid polymer electrode.

The present invention also provides a method of manufacturing an alkali metal battery. In certain embodiments, the method comprises
(A) A combination of an amount of active material (anode active material or cathode active material), an amount of quasi-solid polymer electrolyte (containing a polymer dissolved in a solvent and an alkali metal salt), and a conductive additive. Then, in the step of forming a deformable and conductive electrode material, the conductive additive containing the conductive filament forms a 3D network of electron conduction paths (these conductive materials such as carbon nanotubes and graphene sheets are electrically conductive). Filaments are large numbers of filaments that are randomly agglomerated before being mixed with the particles of active material and the electrolyte The mixing procedure is to convert these conductive filaments into a high viscosity electrolyte containing particles of active material. Distribution, which is discussed further in a later section), steps, and
(B) In the step of forming an electrode material into a quasi-solid electrode, the electrode is 10 ^-6 S/cm or more (preferably 10 ^-5 S/cm or more, more preferably 10 ^-4 S/cm or more, further preferably Is 10 ⁻³ S/cm or more, even more preferably and typically 10 ⁻² S/cm, even more typically and preferably 10 ⁻¹ S/cm, even more typically and preferably 1 S/cm or more; up to 300 S/cm was observed), the electrode material being transformed into an electrode shape without disturbing the 3D network of electron conduction paths.
(C) forming a second electrode (the second electrode can be a quasi-solid polymer electrode or a conventional electrode);
(D) combining a quasi-solid electrode and a second electrode with an ion-conducting separator disposed between the two electrodes to form an alkali metal cell.

As shown in FIG. 1C, one preferred embodiment of the present invention is a conductive quasi-solid polymer anode 236, a conductive quasi-solid polymer cathode 238 (containing a sulfur-containing cathode active material), and an anode. An alkaline ion sulfur cell having a porous separator 240 (or an ion permeable membrane) that electronically separates the cathode. These three components are typically housed in a protective enclosure (not shown), which is typically connected to the anode tab (terminal) and the cathode. And a cathode tab (terminal). These tabs are for connecting an external load (eg, an electronic device to be powered by its battery). In this particular embodiment, the quasi-solid polymer anode 236 includes an anode active material (eg, particles of Li, Si or hard carbon, not shown in FIG. 1C) and an electrolyte phase (typically, It contains a lithium salt or sodium salt dissolved in a solvent and an ion-conducting polymer dissolved, dispersed or impregnated in the solvent; similarly, it is not shown in FIG. 1C), and 3D of an electron conduction path. And a conductive additive (containing a conductive filament) that forms the network 244. Similarly, a quasi-solid polymer cathode contains a sulfur-containing cathode active material, an electrolyte, and a conductive additive (containing a conductive filament) that forms a 3D network 242 of electronic conduction paths.

Another preferred embodiment of the invention shown in FIG. 1(D) is an anode composed of a lithium or sodium metal coating/foil 282 deposited/attached to a current collector 280 (eg Cu foil), An alkali metal-sulfur cell having a quasi-solid polymer cathode 284 and a separator or ion conductive membrane 282. The quasi-solid polymer cathode 284 includes a cathode active material 272 (eg, porous carbon particles impregnated with S or lithium polysulfide or composite particles containing S supported on a graphene sheet) and an electrolyte phase 274 ( Typically containing a lithium or sodium salt dissolved in a solvent and an ion-conducting polymer dissolved, diffused or impregnated in the solvent) and a conductive additive that forms a 3D network 270 of electronic conduction paths. Agent phase (containing a conductive filament).

The electrolyte is preferably a quasi-solid electrolyte containing a lithium salt or sodium salt dissolved in a solvent and a polymer, the complex salt/polymer concentration being ≥1.5 M, preferably >2.5 M, more preferably It is more than 3.5M, more preferably more than 5M, even more preferably more than 7M, even more preferably more than 10M. In certain embodiments, the electrolyte is a quasi-solid polymer electrolyte containing a polymer and a lithium or sodium salt dissolved in a liquid solvent with a complex salt/polymer concentration of 3.0M to 14M. The choice of lithium or sodium salt and solvent is discussed further in a later section.

In some embodiments, the electrolyte is poly(ethylene oxide) (PEO, having a molecular weight of less than 1×10 ⁶ g/mol), polypropylene oxide (PPO), poly(acrylonitrile) (PAN), poly(methyl methacrylate). (PMMA), poly(vinylidene fluoride) (PVdF), polybis-methoxyethoxyethoxide-phosphazene, polyvinyl chloride, polydimethylsiloxane, poly(vinylidene fluoride)-hexafluoropropylene (PVDF-HFP), sulfones thereof. Containing a lithium ion conducting or sodium ion conducting polymer selected from fluorinated derivatives, sulfonated polymers or combinations thereof. Here, sulfonation has been found to improve the lithium ion conductivity of the polymer. Molecular weights of PEO higher than 1×10 ⁶ g/mol typically make it difficult to dissolve or disperse PEO in a solvent.

Typically, the ion conducting polymer does not form a matrix (continuous phase) within the electrode. Instead, the polymer is either dissolved in the solvent as a solution phase or dispersed in the solvent matrix as a discrete phase. The resulting electrolyte is a quasi-solid polymer electrolyte, which is neither a liquid electrolyte nor a solid electrolyte.

The ion conductive polymer is poly(perfluorosulfonic acid), sulfonated polytetrafluoroethylene, sulfonated perfluoroalkoxy derivative of polytetrafluoroethylene, sulfonated polysulfone, sulfonated poly(ether ketone), sulfonated poly(ether ether). Ketone), sulfonated polystyrene, sulfonated polyimide, sulfonated styrene-butadiene copolymer, sulfonated polychloro-trifluoroethylene (PCTFE), sulfonated perfluoroethylene-propylene copolymer (FEP), sulfonated ethylene-chloro. Trifluoroethylene copolymer (ECTFE), Sulfonated polyvinylidene fluoride (PVDF), Sulfonated copolymer of polyvinylidene fluoride and hexafluoropropene and tetrafluoroethylene, Sulfonated copolymer of ethylene and tetrafluoroethylene (ETFE), sulfonated polybenzimidazole (PBI), their chemical derivatives, copolymers, blends and combinations thereof. Surprisingly, the inventors have observed that these sulfonated polymers have both lithium and sodium ion conductivity.

Both the quasi-solid anode and the quasi-solid cathode preferably have a thickness above 200 μm (preferably above 300 μm, more preferably above 400 μm, even more preferably above 500 μm, even more preferably above 800 μm, even more preferably above 1 mm). And can be greater than 5 mm, greater than 1 cm, or even thicker). There is no theoretical limit to the thickness of the electrodes according to the invention. In the cells of the invention, the anode active material is typically 10 mg/cm ² or more (more typically and preferably 20 mg/cm ² or more, more preferably 30 mg/cm ² or more) electrode in the anode. Configure active material loading. When an inorganic material is used as the cathode active material, the cathode active material has an electrode active material loading of 45 mg/cm ² or more (typically and preferably more than 50 mg/cm ² , more preferably more than 60 mg/cm ² ). Constituting (25 mg/cm ² or more in the case of organic or polymer cathode active material).

In such a configuration (FIGS. 1(C) and 1(D)), the electrons are collected by the conductive filament only after traveling a short distance (eg, a few micrometers or less). The conductive filaments make up the 3D network of electronic conduction paths and are ubiquitous throughout the quasi-solid polymer electrode (anode or cathode). Furthermore, all electrode active material particles are pre-dispersed in the electrolyte solvent (without wetting problems) and are commonly present in electrodes prepared by conventional processes of wet coating, drying, packing and electrolyte injection. Eliminate the presence of dry pockets. Therefore, the process or method according to the present invention has totally unexpected advantages over conventional battery cell manufacturing processes.

These conductive filaments (such as carbon nanotubes and graphene sheets) are a large number of filaments that are originally randomly aggregated before being mixed with the particles of the active material and the electrolyte when supplied. The mixing procedure involves dispersing these conductive filaments in an electrolyte such as a high viscosity solid containing particles of active material. This is not as easy as it sounds. Dispersion of nanomaterials (particularly nanofilament materials such as carbon nanotubes, carbon nanofibers and graphene sheets) in high fluid (non-viscous) liquids is known to be very difficult, let alone with high loadings. Not to mention in high-viscosity quasi-solids, such as electrolytes containing active materials (eg Si nanoparticles for the anode and solid particles such as lithium cobalt oxide for the cathode). In some preferred embodiments, this problem is further exacerbated by the electrolyte itself being a quasi-solid polymer electrolyte, containing high concentrations of lithium or sodium salts in the solvent.

In a particular embodiment of the invention, the formation of the electrode layer can be achieved by using the following sequence of steps.

Sequence 1 (S1): First, the lithium salt or sodium salt (eg LiBF ₄ ) and the ion conducting polymer (eg PEO) are dissolved in a mixture of PC and DOL to give the desired complex salt/polymer concentration. An electrolyte having can be formed. The conductive filaments (eg, carbon nanofibers, reduced graphene oxide sheets or CNTs) are then dispersed in the electrolyte to form a filament-electrolyte suspension. Mechanical shear can be used to facilitate the production of a uniform dispersion (this filament-electrolyte suspension is quite viscous even at salt concentrations as low as 1.0M). The particles of cathode active material (eg, S/carbon composite particles) are then dispersed in the filament-electrolyte suspension to form a quasi-solid polymer electrode material.

Sequence 2 (S2): First, the lithium salt or sodium salt and the ion conducting polymer are dissolved in a mixture of PC and DOL to form an electrolyte having the desired complex salt/polymer concentration. The particles of cathode active material are then dispersed in the electrolyte to form an active particle-electrolyte suspension. Mechanical shear can be used to facilitate the production of a uniform dispersion. The conductive filaments are then dispersed in the active particle-electrolyte suspension to form a quasi-solid polymer electrode material.

Sequence 3 (S3): This is the preferred sequence. First, the desired amount of conductive filaments is dispersed in a liquid solvent mixture (PC+DOL) that does not contain dissolved lithium salt or polymer. Mechanical shearing can be used to promote the formation of a uniform suspension of conductive filaments in the solvent. The lithium salt or sodium salt and the ion-conducting polymer are then added to the suspension and the salt and polymer are dissolved in the solvent mixture of the suspension to form an electrolyte with the desired combined salt/polymer concentration. Simultaneously or afterwards, the active material particles are dispersed in the electrolyte to form a deformable quasi-solid electrode material. This quasi-solid electrode material is composed of active material particles and conductive filaments dispersed in a quasi-solid polymer electrolyte (neither a liquid electrolyte nor a solid electrolyte). In this quasi-solid electrode material, the conducting filaments percolate to form a 3D network of electronic conduction paths. This 3D conduction network is maintained when the electrode material is molded into the battery electrodes.

In some preferred embodiments, the electrolyte comprises a polymer and an alkali metal (lithium salt and/or sodium salt) dissolved in an organic or ionic liquid solvent at a sufficiently high complex alkali metal salt/polymer concentration, As a result, the electrolyte has a vapor pressure (measured at 20° C.) of less than 0.01 kPa or 0.6 (60%) of the vapor pressure of the solvent alone, at least 20° C. above the flash point of the first organic liquid solvent alone. High flash point (when no lithium salt is present), flash point higher than 150° C. or no detectable flash point.

Most surprising and of great scientific and technical importance is that if a sufficiently large quantity of alkali metal salt and polymer are added to this organic solvent and dissolved to produce a solid-like or quasi-solid electrolyte. It is the discovery of the present inventors that the flammability of any volatile organic solvent can be effectively suppressed. Generally, such quasi-solid polymer electrolytes are less than 0.01 kPa and often less than 0.001 kPa (measured at 20° C.) and less than 0.1 kPa and often less than 0.01 kPa (measured at 100° C.). Vapor pressure (in the absence of any alkali metal salt and/or polymer dissolved in the solvent, the vapor pressure of the corresponding neat solvent is typically much higher). In many cases featuring quasi-solid polymer electrolytes, vapor molecules are too few to be detected in practice.

A very important observation is that the solubility of the complex of alkali metal salt and polymer in a solvent that is normally highly volatile (typically above 0.2, more typically above 0.3). And a large molecular ratio (molar fraction of the alkali metal salt/polymer chain segment), often greater than 0.4 or even greater than 0.5), allowing volatility to escape into the vapor phase at thermodynamic equilibrium The amount of solvent molecules can be dramatically reduced. In many cases, this effectively prevents flammable solvent gas molecules from producing a flame, even at very high temperatures (eg, using a torch). The flash point of quasi-solid electrolytes is typically at least 20 degrees (often greater than 50 degrees or greater than 100 degrees) above the flash point of neat organic solvent alone. In most cases, the flash point is higher than 150°C or the flash point cannot be detected. The electrolyte does not ignite. In addition, accidental flames do not last longer than a few seconds. Given the view that ignition and explosion concerns are the main obstacles to the wide acceptance of battery-powered electric vehicles, this is a very significant finding. This new technology can greatly help accelerate the emergence of a vibrant EV industry.

For safety considerations, ultra-high concentrations of battery electrolytes (including high molecular weight, eg, alkali metal salt/polymer chain segments with a molecular weight greater than 0.2 or greater than 0.3, or a composite concentration of about 2.5 M No studies have previously been reported for vapor pressures (or above 3.5 M). This is totally unexpected and of highest technical and scientific importance.

Furthermore, the present inventors have found that the presence of a 3D network of electron conduction pathways constituted by conducting nanofilaments acts to further reduce the threshold concentration of alkali metal salt required to achieve the suppression of critical vapor pressure. Unexpectedly discovered to do.

Another surprising element of the present invention is that it is highly soluble in almost all types of commonly used battery grade organic solvents to produce quasi-solid polymer electrolytes suitable for use in rechargeable alkaline metal batteries. The view is that concentrations of alkali metal salts and selected ion-conducting polymers can be dissolved. In simpler terms, this concentration is typically greater than 2.5M (mol/liter), more typically and preferably greater than 3.5M, and even more typically and preferably Is more than 5M, even more preferably more than 7M, most preferably more than 10M. Above 2.5 M salt/polymer concentration, the electrolyte is no longer a liquid electrolyte, but a quasi-solid electrolyte. In the field of lithium or sodium batteries, it is generally believed that such high concentrations of alkali metal salts in a solvent are neither possible nor desirable. However, the present inventors have found that these quasi-solid polymer electrolytes are surprisingly good electrolytes for both lithium batteries and sodium batteries from the viewpoint of significant safety improvement (nonflammability), energy density improvement and power density improvement. I found that.

In addition to the non-flammability and high alkali metal ion transport numbers discussed above, there are some additional benefits associated with the use of the quasi-solid polymer electrolyte according to the present invention. As an example, the quasi-solid polymer electrolyte can significantly improve the cycle performance and safety performance of a rechargeable alkali metal-sulfur battery by effectively suppressing the growth of dendrite when mounted in the anode. .. It is generally accepted that dendrites begin to grow in non-aqueous liquid electrolytes when anions are depleted near the electrodes where plating occurs. In ultra-high-concentration electrolytes, there are large amounts of anions to balance the cations (Li ⁺ or Na ⁺ ) and anions near the metallic lithium or sodium anode. In addition, the space charge produced by anion depletion is minimal, which does not contribute to dendrite growth. Further, due to both the ultra-high Li or Na salt concentration and high Li-ion or Na-ion transport numbers, the quasi-solid polymer electrolyte provides a large amount of available lithium-ion or sodium-ion flux, and the electrolyte and lithium- or sodium electrode. Increase the lithium or sodium ion mass transfer rate between and, thereby improving the uniformity and dissolution of lithium or sodium deposition during the charge/discharge process. Furthermore, the local high viscosity induced by high concentration may increase the pressure from the electrolyte and inhibit the growth of dendrites, resulting in more uniform deposition on the surface of the anode. Also, the high viscosity can limit anion convection near the deposition region and promote more uniform deposition of sodium ions. The same reasoning applies to lithium metal batteries. These reasons, taken individually or in combination, are believed to support that no dendrite-like features were observed in any of the numerous rechargeable alkali metal-sulfur cells we have investigated so far. ..

In addition, those skilled in the chemical or materials science arts would expect such electrolytes to behave like solids with extremely high viscosities due to such high salt/polymer concentrations, and thus the electrolytes should have internal alkali metal It was expected that it would be difficult to undergo the rapid diffusion of ions. As a result, alkali metal batteries containing polymer electrolytes such as solids do not and cannot exhibit high capacity at high charge/discharge rates or under conditions of high current densities (ie battery rate performance Should be low). Contrary to these expectations of those of ordinary and even better skill in the art, all alkali metal-sulfur cells containing such quasi-solid polymer electrolytes offer high energy density and high power density over long cycle life. The quasi-solid polymer electrolytes devised and disclosed herein appear to contribute to easy alkali metal ion transport. This surprising observation result is considered to be due to the following two main factors. That is, one factor is associated with the internal structure of the electrolyte and the other is associated with high Na ⁺ or Li ⁺ ion transport numbers (TN).

Without wishing to be bound by any theory, one can visualize the internal structure of three fundamentally different types of electrolytes, as in FIGS. 2(A)-2(C). FIG. 2A schematically shows a dense, highly ordered structure of a typical solid electrolyte, which has little free volume for diffusion of alkali metal ions. The migration of ions in such a crystal structure is very difficult, with a very low diffusion coefficient (10 ⁻¹⁶ to 10 ⁻¹² cm ² /sec) and a very low ionic conductivity (typically 10 ^{−). 7} S/cm to 10 ⁻⁴ S/cm). In contrast, as shown schematically in FIG. 2B, the internal structure of the liquid electrolyte is completely amorphous and has a large percentage of free volume through which cations (eg, , Li ⁺ or Na ⁺ ) can be easily transferred, a high diffusion coefficient (10 ⁻⁸ to 10 ⁻⁶ cm ² /sec) and a high ionic conductivity (typically 10 ⁻³ S/cm to). 10 ⁻² S/cm). However, liquid electrolytes containing low concentrations of alkali metal salts are flammable and tend to form dendrites, creating the risk of fire and explosion. Shown schematically in FIG. 2(C) is a solvent molecule that separates salts and polymer chain segments to create an amorphous zone in which free (non-clustered) cations can readily migrate. Is a disordered or amorphous structure of a quasi-solid polymer electrolyte containing. Such structures tend to achieve high ionic conductivity values (typically 10 ⁻⁴ S/cm to 8×10 ⁻³ S/cm) and still maintain noncombustibility. Solvent molecules are relatively few and these molecules are conserved (preventing evaporation) by an overwhelming majority of salts, network of polymer chain segments and conducting filaments.

In the Li-S or Na-S cells of the invention, the anode is typically a metal foil, thin film or thin coating (thickness) deposited on a current collector (such as Cu foil or 3D graphene nanostructures). Less than 50 μm) in the form of Li or Na metal.

In some embodiments, the anode active material is pure graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, graphene hydride, graphene nitrogen, chemical. Is a pre-lithiated or pre-sodiumized version of a graphene sheet selected from functionalized graphene or a combination thereof. The starting graphene material for producing any one of the above graphene materials is natural graphite, artificial graphite, mesophase carbon, mesophase pitch, mesocarbon microbeads, soft carbon, hard carbon, coke, carbon fiber, carbon nanofiber. , Carbon nanotubes or a combination thereof. Graphene materials are also good conductivity additives for both anode and cathode active materials in lithium batteries.

Assuming that the interplane van der Waals forces can be overcome, the constituent graphene faces of graphite crystals in natural or artificial graphite particles are exfoliated and extracted or isolated to form individual graphenes of hexagonal carbon atoms. Sheets can be obtained, which are monatomic thick. One manufacturing method is shown in FIG. The isolated individual graphene planes of carbon atoms are commonly referred to as monolayer graphene. A stack of graphene planes joined by van der Waals forces at a graphene plane spacing of about 0.3354 nm in the thickness direction is commonly referred to as multilayer graphene. Multilayer graphene platelets have up to 300 layers of graphene faces (thickness less than 100 nm), but more typically up to 30 layers of graphene faces (thickness less than 10 nm), and even more typically up to 20 layers. Graphene surface (thickness less than 7 nm) and most typically up to 10 layers of graphene surface (commonly referred to as few-layer graphene in the scientific community). Single-layer graphene and multilayer graphene sheets are collectively referred to as "nano-graphene platelets" (NGP). Graphene sheets/platelets (collectively NGP) are a new class of carbon nanomaterials (2D nanocarbons) different from OD fullerene, 1D CNT or CNF and 3D graphite. For purposes of defining the claims and as is generally understood in the art, graphene materials (isolated graphene sheets) are not carbon nanotubes (CNTs) or carbon nanofibers (CNFs) (they are not). Not included).

In one method, as shown in FIG. 5, a graphene material is obtained by intercalating natural graphite particles with a strong acid and/or an oxidizing agent to obtain a graphite intercalation compound (GIC) or graphite oxide (GO). Obtained by The presence of chemical species or functional groups in the interstitial space between the graphene planes in the GIC or GO serves to increase the graphene spacing (d ₀₀₂ ; determined by X-ray diffraction), and thus usually For example, the van der Waals force that holds the graphene surfaces together along the c-axis direction is greatly reduced. GIC or GO is most often produced by immersing natural graphite powder in a mixture of sulfuric acid, nitric acid (oxidizing agent) and another oxidizing agent (eg potassium permanganate or sodium perchlorate). When an oxidizing agent is present during the intercalation procedure, the resulting GIC is actually some graphitic oxide (GO) particles. The GIC or GO was then washed repeatedly and rinsed in water to remove excess acid, resulting in a graphite oxide suspension or dispersion, which was dispersed in water and was discrete and visually distinct. Including graphite oxide particles. One of two process routes can be followed after this rinsing step to produce the graphene material, briefly described below.

Route 1 involves removing water from the suspension to obtain "expanded graphite" which is essentially a mass of dry GIC or dry graphite oxide particles. When the expanded graphite is exposed to temperatures typically in the range of 800-1,050° C. for about 30 seconds to 2 minutes, the GIC rapidly expands in volume 30-300 times to form a “graphite worm”. .. The graphite worms (104) are each a set of exfoliated but hardly separated graphite flakes that remain interconnected.

In Route 1A, these graphite worms (exfoliated graphite or “network of interconnected/non-isolated graphite flakes”) are recompressed, typically 0.1 mm (100 μm) to 0.5 mm. Flexible graphite sheets or foils having a thickness in the range of (500 μm) can be obtained. Alternatively, a graphite worm may simply be used using a low-strength air mill or a shearing machine for the purpose of producing so-called "expanded graphite flakes" which mainly contain graphite flakes or platelets thicker than 100 nm (thus not a nanomaterial by definition). It is also possible to choose to crush.

In Route 1B, exfoliated graphite can be used (e.g., ultrasonic devices, high shear mixers, as disclosed in commonly assigned U.S. Patent Publication No. 200502571574 (September 8, 2005)). Subjected to high strength mechanical shear (using a high strength air jet mill or high energy ball mill) to form separated monolayer and multilayer graphene sheets (collectively referred to as NGP). Single-layer graphene can be as thin as 0.34 nm, while multilayer graphene can have a thickness of up to 100 nm, but more typically less than 10 nm (commonly referred to as few-layer graphene). Multiple graphene sheets or platelets can be formed as a sheet of NGP paper using a papermaking process. This NGP paper is an example of a porous graphene structure layer utilized in the method according to the present invention.

Route 2 involves sonicating a graphite oxide suspension (eg, graphite oxide particles dispersed in water) for the purpose of separating/isolating individual graphene oxide sheets from the graphite oxide particles. This is because the graphene surface separation distance is increased from 0.3354 nm in natural graphite to 0.6 to 1.1 nm in highly oxidized graphite oxide, and van der Waals that holds adjacent surfaces together. It is based on the view that it will weaken significantly. The ultrasonic power may be sufficient to further separate the graphene face sheet to form a fully separated, isolated or discrete graphene oxide (GO) sheet. These graphene oxide sheets can then be chemically or thermally reduced to give "reduced graphene oxide" (RGO), which typically ranges from 0.001% to 10% by weight, More typically it has an oxygen content of 0.01 wt% to 5 wt% and most typically and preferably comprises less than 2 wt% oxygen.

For purposes of defining the claims of this application, NGP or graphene materials include mono- and multi-layer (typically less than 10 layers) pure graphene, graphene oxide, reduced graphene oxide (RGO), graphene fluoride. , Graphene chloride, graphene bromide, graphene iodide, graphene hydride, graphene nitride, chemically functionalized graphene, discrete sheets/platelets of doped (eg, B or N doped) graphene. Pure graphene has essentially 0% oxygen. RGOs typically have an oxygen content of 0.001% to 5% by weight. Graphene oxide (including RGO) can have 0.001 wt% to 50 wt% oxygen. With the exception of pure graphene, all graphene materials contain 0.001% to 50% by weight of non-carbon elements (eg, O, H, N, B, F, Cl, Br, I, etc.). These materials are referred to herein as impure graphene materials.

Pure graphene is produced by direct sonication (also known as liquid phase exfoliation or generation) or supercritical fluid exfoliation of graphite particles as smaller discrete graphene sheets (typically 0.3 μm-10 μm). can do. These methods are well known in the art.

Graphene oxide (GO) is a starting graphite material at a desired temperature in a reaction vessel over a period of time (typically 0.5-96 hours depending on the nature of the starting material and the type of oxidant used). Can be obtained by dipping the powder or filament (for example, natural graphite powder) in an oxidizing liquid medium (for example, a mixture of sulfuric acid, nitric acid and potassium permanganate). The resulting graphite oxide particles can then be subjected to thermal or ultrasonic induced exfoliation to produce isolated GO sheets, as described above. Then, these GO sheets can convert the OH groups other chemical groups (e.g., Br, etc. NH ₂₎ in a variety of graphene materials by replacing.

In this specification, fluorinated graphene or fluorinated graphene is used as an example of the halogenated graphene material group. There are two different approaches that have been taken to produce fluorinated graphene. (1) Fluorination of pre-synthesized graphene: This approach requires treating graphene prepared by mechanical exfoliation or CVD growth with a fluorinating agent such as XeF ₂ or F-based plasma. (2) Exfoliation of multi-layered fluorinated graphite: Both mechanical exfoliation and liquid phase exfoliation of fluorinated graphite can be easily achieved.

Graphite intercalation compound (GIC) C _x F (2≦x≦24) is produced at low temperature, whereas the interaction between F ₂ and graphite at high temperature is due to covalent fluorinated graphite (CF). _n or (C ₂ F) _n . In (CF) _n , the carbon atoms are sp3 hybridized, so the fluorocarbon layer is corrugated, consisting of the translinked cyclohexane chair conformation. In (C 2 _{F) n,} only one half of the C atoms are fluorinated, none pair of carbon sheets adjacent are coupled by covalent C-C bonds. From the systematic study on the fluorination reaction, the obtained F/C ratio is determined by the fluorination temperature, the partial pressure of fluorine in the fluorination gas and the physical properties of the graphite precursor such as the degree of graphitization, the particle size and the specific surface area. It was shown to be highly dependent. In addition to fluorine (F ₂ ), other fluorinating agents can also be used, but most of the available literature involves fluorination with F ₂ gas, sometimes in the presence of fluoride.

In order to exfoliate the layered precursor material into individual layers or layers, it is necessary to overcome the attractive forces between adjacent layers and to further stabilize the layers. This can be achieved by covalent modification of the graphene surface with functional groups or by non-covalent modification using specific solvents, surfactants, polymers or donor-acceptor aromatic molecules. The process of liquid phase exfoliation involves sonication of fluorinated graphite in a liquid medium.

Nitrogenation of graphene can be performed by exposing graphene materials such as graphene oxide to ammonia at high temperatures (200-400°C). Nitrogenated graphene can also be produced at lower temperatures by the hydrothermal method. This is done, for example, by sealing GO and ammonia in an autoclave and then raising the temperature to 150-250°C. Other methods of synthesizing nitrogen-doped graphene include nitrogen plasma treatment of graphene, arc discharge between graphite electrodes in the presence of ammonia, ammonolysis of graphene oxide under CVD conditions and graphene oxide at various temperatures. Includes hydrothermal treatment of urea.

There is no limitation on the type of anode active material that can be used in the practice of the present invention. Preferably, in the lithium-sulfur cell of the present invention, the anode active material is less than 1.0 Volt than Li/Li ⁺ (ie relative to Li→Li ⁺ +e ⁻ as a standard potential) when the battery is charged. Absorbs lithium ions with high electrochemical potential (preferably less than 0.7 volts). In one preferred embodiment, the lithium battery anode active material comprises (a) particles of lithium metal or lithium metal alloy and (b) natural graphite particles, artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles ( (Including soft carbon and hard carbon), needle coke, carbon nanotube, carbon nanofiber, carbon fiber and graphite fiber, and (c) silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), nickel (Ni), cobalt (Co), manganese (Mn), titanium (Ti), iron (Fe) and cadmium (Cd), (D) An alloy or intermetallic compound of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al or Cd and another element, which is stoichiometric or non-stoichiometric. An intermetallic compound and (e) an oxide, a carbide, or a nitride of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ni, Co, Ti, Mn or Cd and a mixture or composite thereof. It is selected from the group consisting of sulfides, phosphides, selenides and tellurides, (f) prelithiated versions thereof, (g) prelithiated graphene sheets, and combinations thereof.

In certain embodiments, the alkali metal-sulfur cell is a sodium ion sulfur cell and the active material is petroleum coke, carbon black, amorphous carbon, activated carbon, hard carbon (carbon that is difficult to graphitize), soft carbon. Carbon (carbon which can be easily graphitized), template carbon, hollow carbon nanowire, hollow carbon sphere, titanate, NaTi ₂ (PO ₄ ) ₃ , Na ₂ Ti ₃ O ₇ , Na ₂ C ₈ H ₄ O ₄ , Na. _{2 TP, Na x TiO 2 (} x = 0.2~1.0), Na 2 C 8 H 4 O 4, the carboxylic acid-based _{material, C 8 H 4 Na 2 O} 4, C 8 H 6 O 4, _{C 8 H 5 NaO 4, C} 8 Na 2 F 4 O 4, C 10 H 2 Na 4 O 8, C 14 H 4 O 6, C 14 H 4 Na 4 O 8 , or sodium are selected inter combinations thereof It is an anode active material containing a curation compound.

In certain embodiments, the alkali metal-sulfur cell is a sodium metal-sulfur cell or sodium ion sulfur cell, and the active material is (a) particles of sodium metal or sodium metal alloy and (b) natural graphite particles. , Artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle cokes, carbon nanotubes, carbon nanofibers, carbon fibers and graphite fibers, and (c) sodium-doped silicon (Si), germanium (Ge) , Tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), titanium (Ti), cobalt (Co), nickel (Ni), manganese (Mn). , Cadmium (Cd) and mixtures thereof, and (d) sodium-containing alloys or intermetallics of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Co, Ni, Mn, Cd and mixtures thereof. Compounds and (e) sodium-containing oxides, carbides, and nitrides of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ti, Co, Ni, Mn, Cd, and mixtures or composites thereof. Selected from the group consisting of, sulfides, phosphides, selenides, tellurides or antimonides, (f) sodium salts, (g) graphene sheets preloaded with sodium ions, and combinations thereof. It is an active material.

A wide variety of sulfur-based cathode active materials can be used to implement the lithium sulfur or sodium sulfur cells of the present invention. Such sulfur-containing cathode active materials include sulfur, metal-sulfur compounds (eg, lithium polysulfide), sulfur-carbon composites (eg, carbon black-S composite prepared by ball milling, or S-impregnated porous material. Carbon particles), sulfur-graphene composites, sulfur-graphite composites, organic sulfur compounds, sulfur-polymer composites or combinations thereof.

In some embodiments, the cathode active material may be selected from sulfur or sulfur compounds supported by or bound to functional materials or nanostructured materials. The functional material or nanostructured material is (a) soft carbon, hard carbon, polymer carbon or carbonized resin, mesophase carbon, coke, carbonized pitch, carbon black, activated carbon, nanocell carbon foam or partially graphitized. Nanostructured or porous disordered carbon material selected from carbon, (b) nanographene platelets selected from single-layer graphene sheets or multilayer graphene platelets, and (c) selected from single-wall carbon nanotubes or multi-wall carbon nanotubes Carbon nanotubes, (d) carbon nanofibers, nanowires, metal oxide nanowires or fibers, conductive polymer nanofibers or combinations thereof, (e) carbonyl-containing organic or polymer molecules, and (f) carbonyl groups, It may be selected from the group consisting of functional materials containing carboxyl or amine groups and combinations thereof.

The functional material or the nanostructured material is poly(2,5-dihydroxy-1,4-benzoquinone-3,6-methylene), Na _x C ₆ O ₆ (x=1 to 3), Na ₂ (C _{6 H 2 O 4), Na 2} C 8 H 4 O 4 (Na _{terephthalate), Na 2 C 6 H 4} O 4 (Na trans - trans - muconic acid salt), 3,4,9,10-perylenetetracarboxylic acid Dianhydride (PTCDA) sulfide polymer, PTCDA, 1,4,5,8-naphthalene-tetracarboxylic dianhydride (NTCDA), benzene-1,2,4,5-tetracarboxylic dianhydride , 1,4,5,8-tetrahydroxyanthraquinone, tetrahydroxy-p-benzoquinone and combinations thereof. Desirably, the functional material or nanostructured materials, -COOH, = _O, -NH 2, a functional group selected from -OR or -COOR, wherein, R is a hydrocarbon radical.

Single-layer or few-layer (up to 20 layers) non-graphene 2D nanomaterials can be produced by several methods, including: Mechanical cleavage, laser ablation (eg, ablation of TMD to a single layer using laser pulses), liquid phase exfoliation, synthesis by thin film techniques, eg PVD (eg sputtering), evaporation, vapor phase epitaxy, liquid phase Epitaxy, chemical vapor epitaxy, molecular beam epitaxy (MBE), atomic layer epitaxy (ALE) and their plasma-assisted versions.

A wide variety of electrolytes can be used to practice the invention. Most preferred are non-aqueous organic and/or ionic liquid electrolytes. The non-aqueous electrolyte that can be used in the present invention can be produced by dissolving an electrolyte salt in a non-aqueous solvent. Any known non-aqueous solvent that has been adopted as a solvent for a lithium secondary battery can be adopted. A mixture mainly containing ethylene carbonate (EC) and at least one non-aqueous solvent having a melting point lower than that of the ethylene carbonate and having a donor number of 18 or less (hereinafter referred to as a second solvent) A non-aqueous solvent consisting of a solvent can be preferably used. This non-aqueous solvent is (a) stable to a negative electrode containing a carbonaceous material having a fully developed graphite structure, (b) effective in suppressing reduction or oxidative decomposition of the electrolyte, and (c). It is advantageous in that it has high conductivity. Non-aqueous electrolytes composed solely of ethylene carbonate (EC) are advantageous in that they are relatively stable to decomposition by reduction on graphitized carbonaceous materials. However, since the melting point of EC is relatively high at 39 to 40° C. and its viscosity is also relatively high, its electrical conductivity is low. Therefore, EC alone cannot be used as an electrolyte of a secondary battery operated at room temperature or below. Not suitable. The second solvent used in the mixture with EC serves to make the viscosity of the solvent mixture lower than that of EC alone, thereby promoting the ionic conductivity of the mixed solvent. Further, when a second solvent having a donor number of 18 or less (the donor number of ethylene carbonate is 16.4) is adopted, the above-mentioned ethylene carbonate can be easily and selectively solvated with lithium ions. Therefore, it is assumed that the reduction reaction between the second solvent and the carbonaceous material sufficiently developed into the graphitized state is suppressed. Further, when the number of donors of the second solvent is controlled to be 18 or less, the oxidative decomposition potential to the lithium electrode can be easily increased to 4 V or more, and thus a high voltage lithium secondary battery can be manufactured. Is.

Preferred second solvent is dimethyl carbonate (DMC), methyl ethyl carbonate (MEC), diethyl carbonate (DEC), ethyl propionate, methyl propionate, propylene carbonate (PC), gamma-butyrolactone (γ-BL), acetonitrile. (AN), ethyl acetate (EA), propyl formate (PF), methyl formate (MF), toluene, xylene and methyl acetate (MA). These second solvents may be used alone or in combination of two or more. More desirably, this second solvent should be selected from those having a donor number of 16.5 or less. The viscosity of this second solvent should preferably not exceed 28 cps at 25°C.

The mixing ratio of the above ethylene carbonate in the mixed solvent should preferably be 10 to 80% by volume. If the mixing ratio of ethylene carbonate is out of this range, the conductivity of the solvent may be lowered, or the solvent may be more easily decomposed, thereby lowering the charge/discharge efficiency. A more preferable mixing ratio of ethylene carbonate is 20 to 75% by volume. When the mixing ratio of ethylene carbonate in the non-aqueous solvent is increased to 20% by volume or more, the solvating effect of ethylene carbonate on lithium ions is promoted and the solvent decomposition inhibiting effect can be improved.

Examples of preferable mixed solvents include a composition containing EC and MEC, a composition containing EC, PC and MEC, a composition containing EC, MEC and DEC, a composition containing EC, MEC and DMC, EC, MEC, PC And DEC, and the volume ratio of MEC is controlled within the range of 30 to 80%. The conductivity of the solvent can be improved by selecting the volume ratio of MEC in the range of 30 to 80%, more preferably 40 to 70%. For the purpose of suppressing the decomposition reaction of the solvent, an electrolyte in which carbon dioxide is dissolved can be adopted, whereby both the capacity and cycle life of the battery can be effectively improved. The electrolyte salt taken into the non-aqueous electrolyte is lithium perchlorate (LiClO ₄ ), lithium hexafluorophosphate (LiPF ₆ ), lithium borofluoride (LiBF ₄ ), lithium hexafluoroarsenide (LiAsF ₆ ), trifluorometamet lithium sulfonate (LiCF ₃ SO ₃₎ and bis - it may be selected from lithium salts such as trifluoromethyl sulfonyl imide lithium _{[LiN (CF 3 SO 2)} 2]. Among them, LiPF ₆ , LiBF ₄ and LiN(CF ₃ SO ₂ ) ₂ are preferable. The content of the electrolyte salt in the non-aqueous solvent is preferably 0.5 to 2.0 mol/liter.

In the case of a sodium cell, the electrolyte (including non-combustible quasi-solid electrolyte) is preferably sodium perchlorate (NaClO ₄ ), sodium hexafluorophosphate (NaPF ₆ ), sodium borofluoride (NaBF ₄ ), hexafluorohidden. sodium reduction, sodium trifluoro meth acid _(NaCF 3 _SO 3), bis - trifluoromethyl sulfonyl imide sodium _{(NaN (CF 3 SO 2)} 2), containing a sodium salt selected from the ionic liquid salts or their combinations You can

Ionic liquids are composed only of ions. Ionic liquids are low melting temperature salts that are in a molten or liquid state when the desired temperature is exceeded. For example, a salt is considered an ionic liquid if its melting point is below 100°C. If the melting temperature is below room temperature (25° C.), the salt is called a room temperature ionic liquid (RTIL). IL salts are characterized by weak interactions due to the combination of large cations and charge delocalized anions. This reduces the tendency for crystallization due to flexibility (anion) and asymmetry (cation).

The combination of the 1-ethyl-3-methylimidazolium (EMI) cation and the N,N-bis(trifluoromethane)sulfonamide (TFSI) anion forms a typical and well known ionic liquid. This combination results in a fluid with ionic conductivity and low degradability and low vapor pressure comparable to many organic electrolyte solutions up to about 300-400°C. This generally suggests a low volatility and non-flammability, and thus a much safer electrolyte for batteries.

Ionic liquids are basically composed of organic ions that produce an essentially unlimited number of structural changes due to the ease of preparation of the various components. Thus, various types of salts can be used to design ionic liquids with the desired properties for a given application. These include, among others, imidazolium, pyrrolidinium and quaternary ammonium salts as cations, and bis(trifluoromethanesulfonyl)imides, bis(fluorosulfonyl)imides and hexafluorophosphates as anions. Ionic liquids are basically divided into various classes based on their composition, including aprotic, protic and zwitterionic types, each suitable for a particular application.

Common cations of room temperature ionic liquids (RTIL) include, but are not limited to, tetraalkylammonium, di-, tri- and tetra-alkylimidazolium, alkylpyridinium, dialkylpyrrolidinium, dialkylpiperidinium, tetraalkyl. Examples include phosphonium as well as trialkylsulfonium. General anions of RTIL include, but are not limited to, BF ₄ ⁻ , B(CN) ₄ ⁻ , CH ₃ BF ₃ ⁻ , CH ₂ CHBF ₃ ⁻ , CF ₃ BF ₃ ⁻ , C ₂ F ₅ BF ₃ ⁻ , n. ^{_{-C 3 F 7 BF 3 -,}} n-C 4 F 9 BF 3 -, PF 6 -, CF 3 CO 2 -, CF 3 SO 3 -, n (SO 2 CF 3) 2 -, n (COCF 3) ^{_{(SO 2 CF 3) -,}} N (SO 2 F) 2 -, N (CN) 2 -, C (CN) 3 -, SCN -, SeCN -, CuCl 2 -, AlCl 4 -, F (HF) 2 _{. 3} ^{− and the} like. Relatively speaking, imidazolium- or sulfonium-based cations and AlCl ₄ ⁻ , BF ₄ ⁻ , CF ₃ CO ₂ ⁻ , CF ₃ SO ₃ ⁻ , NTf ₂ ⁻ , N(SO ₂ F) ₂ ⁻ or F( _{HF) 2.3} ^- combination with complex halide anions, such as results in a RTIL having good operation conductivity.

RTILs have high intrinsic ionic conductivity, high thermal stability, low volatility, low (substantially zero) vapor pressure, non-flammability, and the ability to maintain liquids over a wide temperature range above and below room temperature. , Can have typical properties such as high polarity, high viscosity and wide electrochemical window. These properties, except for high viscosity, are desirable attributes when using RTIL as the electrolyte component (salt and/or solvent) in supercapacitors.

In the following, some examples of several different types of anode active materials, sulfur-based cathode active materials and ion-conducting polymers are provided to show the best mode of carrying out the invention. These exemplary embodiments and the rest of the description and the drawings, individually or in combination, are more than sufficient to enable those skilled in the art to practice the invention. However, these examples should not be construed as limiting the scope of the invention.

Example 1: Preparation of graphene oxide (GO) and reduced graphene oxide (RGO) nanosheets from natural graphite powder Huadong Graphite Co. Natural graphite (Qingdao, China) was used as the starting material. GO was obtained by following the well-known modified Hummers method. This method involves two oxidation steps. In a typical procedure, the first oxidation was achieved under the following conditions. 1100 mg of graphite was placed in a 1000 mL boiling flask. Then K ₂ S ₂ O ₈ , 20 g P ₂ O ₅ and 400 mL concentrated aqueous H ₂ SO ₄ solution (96%) were added to the flask. The mixture was heated under reflux for 6 hours and then left at room temperature for 20 hours. The graphite oxide was filtered and rinsed with a large amount of distilled water until it had a neutral pH. At the end of this first oxidation, a wet cake was recovered.

In the second oxidation process, the wet cake previously collected was placed in a boiling flask containing 69 mL of concentrated H ₂ SO ₄ aqueous solution (96%). The flask was kept in an ice bath while slowly adding 9 g of KMnO ₄ . Care was taken to avoid overheating. The resulting mixture was stirred at 35° C. for 2 hours (sample color changed to dark green), followed by addition of 140 mL of water. After 15 minutes, the reaction was stopped by adding 420 mL of water and 15 mL of 30 wt% H ₂ O ₂ aqueous solution. The color of the sample at this stage turned bright yellow. The mixture was filtered and rinsed with 1:10 aqueous HCl to remove metal ions. The collected material was gently centrifuged at 2700 g and rinsed with deionized water. The final product was a wet cake containing 1.4 wt% GO, as estimated from the dry extract. Then, the wet cake material diluted with deionized water was lightly sonicated to obtain a liquid dispersion of GO platelets.

RGO (RGO-BS) stabilized with a surfactant was obtained by diluting the wet cake with a surfactant aqueous solution instead of pure water. A commercial mixture of salts of sodium cholate (50 wt%) and sodium deoxycholate (50 wt%) provided by Sigma Aldrich was used. The weight fraction of surfactant was 0.5 wt %. This fraction was kept constant for all samples. Sonication was performed using a Branson Sonifier S-250A equipped with a 13 mm step distractor horn and a 3 mm tapered microchip and operating at a frequency of 20 kHz. For example, 10 mL of an aqueous solution containing 0.1 wt% GO was sonicated for 10 minutes and then centrifuged at 2700 g for 30 minutes to remove undissolved large particles, aggregates and impurities. The GO obtained as described above was chemically reduced to produce RGO by following a method comprising placing 10 mL of 0.1 wt% GO aqueous solution in a 50 mL boiling flask. Then, to the mixture stabilized by the surfactant, 10 μL of 35 wt% N ₂ H ₄ (hydrazine) aqueous solution and 70 mL of 28 wt% NH ₄ OH (ammonia) aqueous solution were added. The solution was heated to 90° C. and refluxed for 1 hour. The pH value measured after the reaction was about 9. The color of the sample turned dark black during the reduction reaction.

RGO was used as a conductive additive for one or both of the anode and cathode active materials in certain lithium-sulfur batteries of the present invention. Pre-lithiated RGO (eg, RGO+lithium particles or pre-deposited RGO with lithium coating) was also used as the anode active material in selected lithium-sulfur cells.

For comparison, a slurry coating and drying procedure was performed to make a conventional electrode. Then, one anode and one cathode, and a separator disposed between the two electrodes are assembled and housed in an Al plastic laminate packaging container, after which a liquid electrolyte is injected to obtain lithium in the prior art. A battery cell was formed.

Example 2: Preparation of pure graphene sheet (essentially 0% oxygen)
Recognizing that the high defect counts in GO sheets can act to reduce the conductivity of individual graphene planes, we have found that pure graphene sheets (non-oxidized and oxygen-free, non-halogenated and It was decided to investigate whether the use of (eg halogen-free) could lead to conductive additives with high electrical conductivity and high thermal conductivity. Pre-lithiated pure graphene was also used as the anode active material. Pure graphene sheets were manufactured using direct sonication or liquid phase manufacturing process.

In a typical procedure, 5 grams of graphite flakes milled to a size of about 20 μm or less contains 1,000 mL of deionized water (0.1 wt% dispersant, DuPont Zonyl® FSO. ), and a suspension was obtained. An ultrasonic energy level of 85 W (Branson S450 Ultrasonicator) was used to peel, separate and reduce the size of the graphene sheets over a period of 15 minutes to 2 hours. The resulting graphene sheet is pure graphene that has not been oxidized, is oxygen free, and relatively defect free. Pure graphene is substantially free of any non-carbon elements.

The pure graphene sheet as the conductive additive is then used as an anode active material (or cathode) using both the slurry pouring procedure according to the invention and the conventional slurry coating, drying and laminating procedures. (Cathode active material in the above) and incorporated into a battery. Both lithium ion sulfur batteries and lithium metal-sulfur batteries were investigated.

Example 3: Preparation of Pre-lithiated Graphene Fluoride Sheet as Anode Active Material for Lithium Ion Batteries To make GF, we have used several processes, but here are examples. Will describe only one process. In a typical procedure, highly exfoliated graphite (HEG) was prepared from the intercalated compound C ₂ F.xClF ₃ . HEG was further fluorinated with chlorine trifluoride vapor to produce fluorinated highly exfoliated graphite (FHEG). Pre-cooled liquid-filled pre-cooling ClF ₃ of 20~30mL Teflon reactor and cooled to liquid nitrogen temperature by closing the reactor. Then, 1 g or less of HEG was placed in a container having a hole for ClF ₃ gas to access, and the HEG was placed inside the reactor. Gray beige product of the approximate formula C _{2 F} are formed in 7-10 days.

Then, a small amount of FHEG (about 0.5 mg) was mixed with 20 to 30 mL of organic solvent (individually methanol and ethanol) and sonicated (280 W) for 30 minutes to produce a homogeneous yellowish dispersion. .. After removal of the solvent, the dispersion became a brownish powder. Graphene fluoride powder was mixed with surface-stabilized lithium powder in a liquid electrolyte to allow prelithiation.

Example 4: Some Examples of Preferred Salts, Solvents, Polymers for Forming a Quasi-Solid Polymer Electrolyte Preferred sodium metal salts include: Sodium perchlorate (NaClO ₄ ), sodium hexafluorophosphate (NaPF ₆ ), sodium borofluoride (NaBF ₄ ), sodium hexafluoroarsenide, potassium hexafluoroarsenide, sodium trifluoro-metasulfonate (NaCF ₃ SO _{3 ).} ) and bis - trifluoromethyl sulfonyl imide sodium _{(NaN (CF 3 SO 2)} 2). The following are good choices for lithium salts that tend to be well soluble in the organic or ionic liquid solvent of choice. Lithium borofluoride (LiBF _4), trifluoro - Lithium methanesulfonic acid _(LiCF 3 _SO 3), lithium bis - trifluoromethylsulfonyl imide _{(LiN (CF 3 SO 2)} 2 or LiTFSI), lithium-bis (oxalato) borate ( LiBOB), oxalyl lithium difluoro borate (liBF2C ₂ O ₄₎ and bis perfluoro ethyl - imide lithium (LiBETI). A good electrolyte additive that helps to stabilize Li metal is LiNO ₃ . Particularly useful ionic liquid-based lithium salts include lithium bis(trifluoromethanesulfonyl)imide (LiTFSI).

In the case of aqueous electrolytes, the sodium or potassium salts are preferably Na ₂ SO ₄ , K ₂ SO ₄ , mixtures thereof, NaOH, KOH, NaCl, KCl, NaF, KF, NaBr, KBr, NaI, KI or theirs. Selected from a mixture of. The salt concentration used in this study was 0.3M to 3.0M (0.5M to 2.0M in most cases).

The following are mentioned as a preferable organic liquid solvent. Ethylene carbonate (EC), dimethyl carbonate (DMC), methyl ethyl carbonate (MEC), diethyl carbonate (DEC), propylene carbonate (PC), acetonitrile (AN), vinylene carbonate (VC), allyl ethyl carbonate (AEC), 1, 3-dioxolane (DOL), 1,2-dimethoxyethane (DME), tetraethylene glycol dimethyl ether (TEGDME), poly(ethylene glycol) dimethyl ether (PEGDME), diethylene glycol dibutyl ether (DEGDBE), 2-ethoxyethyl ether (EEE) , Hydrofluoroethers (eg TPTP), sulfones and sulfolanes.

Preferred ionic liquid solvents may be selected from room temperature ionic liquids (RTILs) having a cation selected from tetraalkylammonium, di-alkylimidazolium, alkylpyridinium, dialkyl-pyrrolidinium or dialkylpiperidinium. The counter anion is preferably BF ₄ ⁻ , B(CN) ₄ ⁻ , CF ₃ CO ₂ ⁻ , CF ₃ SO ₃ ⁻ , N(SO ₂ CF ₃ ) ₂ ⁻ , N(COCF ₃ ) (SO ₂ CF ₃ ). ) ⁻ Or N(SO ₂ F) ₂ ⁻ . Particularly useful ionic liquid-based solvents include: N-n-butyl-N-ethylpyrrolidinium bis(trifluoromethanesulfonyl)imide (BEPyTFSI), N-methyl-N-propylpiperidinium bis(trifluoromethylsulfonyl)imide (PP ₁₃ TFSI) and N,N. -Diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)imide.

The following are mentioned as preferable lithium ion conduction or sodium ion conduction polymers. Poly(ethylene oxide) (PEO, having a molecular weight of less than 1×10 ⁶ g/mol), polypropylene oxide (PPO), poly(acrylonitrile) (PAN), poly(vinylidene fluoride)-hexafluoropropylene (PVDF-HFP). And sulfonated polymers. The following are mentioned as a preferable sulfonated polymer. Poly(perfluorosulfonic acid), sulfonated polytetrafluoroethylene, sulfonated polysulfone, sulfonated poly(ether ether ketone) (S-PEEK) and sulfonated polyvinylidene fluoride (S-PVDF).

Example 5: Several solvents and the corresponding quasi-solid electrolyte vapor pressure borofluoride sodium (NaBF _4), sodium perchlorate (NaClO ₄₎ or bis (trifluoromethanesulfonyl) imide sodium at various sodium salt molar ratio Some solvents (DOL, DME, PC, AN, ionic liquid based co-solvent PP ₁₃ TFSI with or without a wide range of sodium salts such as (NaTFSI) before and after addition with PEO. ) Vapor pressure was measured. The vapor pressure drops very rapidly above the salt/polymer concentration of the complex above 2.3M and rapidly approaches a minimum or essentially zero above the concentration of complex above 3.0M. If the vapor pressure is too low, the vapor phase of the electrolyte will not be able to generate a flame or sustain it for more than 3 seconds after generation.

Example 6: Complex sodium or lithium salt/flash point and vapor pressure of some solvents and corresponding quasi-solid polymer electrolytes with polymer concentration of 3.0 M Na or Li salt/some with polymer concentration of 3 M The flash points and vapor pressures of the solvents and their electrolytes are shown in Table 1 below. It should be noted that according to the OSHA (US Occupational Safety and Health Administration) classification, any liquid with a flash point below 38.7°C is flammable. However, in order to ensure safety, we have a flash point significantly higher than 38.7° C. (eg higher by at least 50° C., preferably higher than 150° C. with a large margin). A quasi-solid electrolyte was designed as shown. The data in Table 1 show that the addition of 3.0M complex alkali metal salt/polymer concentration is usually sufficient to meet these criteria (often 2.3M is sufficient). is there). All of the quasi-solid polymer electrolytes by the present inventors are not flammable.

Example 7: Alkali metal ion transport numbers in some electrolytes Study Na ⁺ ion transport numbers of several types of electrolytes (eg (PEO+NaTFSI salt) in (EMImTFSI+DME) solvent) related to the molecular ratio of the lithium salt. did. Representative results are summarized in FIGS. 3(A)-3(B). In general, Na ⁺ ion transport numbers in low salt electrolytes decrease with increasing concentration from x=0 to x=0.2-0.30. However, when the molecular ratio of x = 0.2 to 0.30 is exceeded, the transport number increases with an increase in salt concentration, which shows a fundamental change in the Na ⁺ ion transport mechanism. A similar tendency was observed for lithium ions.

As Na ⁺ ions migrate through a low salt concentration electrolyte (eg, x<0.2), they can drag with them multiple solvating molecules. The coordinated migration of such clusters of charged species can be further hindered if the fluid viscosity is increased by more salt and polymer dissolved in the solvent. In contrast, Na ⁺ ions can significantly exceed the number of available solvating molecules in the presence of very high concentrations of sodium salts with x>0.2. Such solvating molecules are normally capable of clustering sodium ions, forming multi-ionic complex species and slowing the diffusion process of Na ⁺ ions. This high Na ⁺ ion concentration allows having more “free Na ⁺ ions” (not clustered), thereby providing a higher Na ⁺ transport number (and thus easier Na ⁺ transport). .. The sodium ion transport mechanism is from a multi-ion complex dominating mechanism (having a larger overall hydrodynamic radius) to a single ion dominating mechanism having a large number of available free Na ⁺ ions (smaller hydrodynamic radius). Have). This observation indicates that an appropriate number of Na ⁺ ions can be rapidly moved through or out of the quasi-solid electrolyte, which may lead to interactions or reactions with the cathode (during discharge) or the anode (during charge). It further claims to be readily available, thereby ensuring good rate performance of sodium secondary cells. Most importantly, these concentrated electrolytes are nonflammable and safe. Therefore, it has been very difficult to obtain a combination of safety, easy sodium ion transport, and electrochemical performance characteristics for all types of sodium and lithium secondary batteries.

Example 8: Preparation of Sulfur/Carbon Black (S/CB) Composite Particles for Lithium Sulfur Battery Cathode Sulfur powder and CB particles were mixed (ratio 70/30) and ball milled for 2 hours. S/CB particles were obtained. In this example, an electrode containing S/CB particles as a cathode active material and an electrolyte (containing a lithium salt and a polymer dissolved in an organic solvent) was used as a conductive filament for a graphene sheet (RGO) and a carbon nanofiber ( CNF) was included separately. The lithium salt used in this example comprises lithium borofluoride (LiBF ₄ ) and the organic solvent is PC, DOL, DEC and mixtures thereof. This study included a wide range of conductive filament volume fractions from 0.1% to 30%. The formation of the electrode layer was achieved by using the following series of steps.

Sequence 1 (S1): First, LiBF ₄ salt and PEO are dissolved in a mixture of PC and DOL to form an electrolyte having a combined salt/polymer concentration of 1.0M, 2.5M and 3.5M, respectively. (At concentrations of 2.3M and above, the resulting electrolyte was no longer a liquid electrolyte; in fact, it behaved more like a solid, thus using the term "quasi-solid"). The RGO or CNT filament was then dispersed in the electrolyte to form a filament-electrolyte suspension. Mechanical shear was used to facilitate the formation of a uniform dispersion (this filament-electrolyte suspension was quite viscous even at low salt concentrations of 1.0M). Then, the cathode active material S/CB particles were dispersed in the filament-electrolyte suspension to form a quasi-solid polymer electrode material.

Sequence 2 (S2): First, LiBF ₄ salt and PEO are dissolved in a mixture of PC and DOL to form an electrolyte having a combined salt/polymer concentration of 1.0M, 2.5M and 3.5M, respectively. did. Then, the S/CB particles as the cathode active material were dispersed in the electrolyte to form an active particle-electrolyte suspension. Mechanical shear was used to facilitate the production of a uniform dispersion (this active particle-electrolyte suspension was quite viscous even at low salt concentrations of 1.0M). The RGO or CNT filament was then dispersed in the active particle-electrolyte suspension to form a quasi-solid polymer electrode material.

Sequence 3 (S3): First, the desired amount of RGO or CNT filaments was dispersed in a liquid solvent mixture (PC+DOL) containing no dissolved lithium salt or polymer. Mechanical shear was used to promote the formation of a uniform suspension of conductive filaments in the solvent. Then LiBF ₄ salt, PEO and S/CB particles were added to the suspension and LiBF ₄ salt and PEO were dissolved in the suspension solvent mixture to give 1.0M, 2.5M and 3.5M respectively. An electrolyte was formed having a combined salt/polymer concentration of. Simultaneously or afterwards, the S/CB particles were dispersed in the electrolyte to form a deformable quasi-solid electrode material. This quasi-solid electrode material is composed of active material particles and conductive filaments dispersed in a quasi-solid polymer electrolyte (neither a liquid electrolyte nor a solid electrolyte). In this quasi-solid electrode material, the conducting filaments percolate to form a 3D network of electronic conduction paths. This 3D conduction network is maintained when the electrode material is molded into the battery electrodes.

The conductivity of the electrodes was measured using the 4-point probe method. The results are summarized in Figures 5(A) and 5(B). As these data show, typically the percolation of conductive filaments (CNFs or RGOs) to form a 3D network of electronic conduction paths, except for the electrodes formed by Sequence 3 (S3) below. , Does not occur until the volume fraction of the conductive filament exceeds 10 to 12%. In other words, the step of dispersing the conductive filaments in the liquid solvent must be performed before the lithium salt, sodium salt or ion conductive polymer is dissolved in the liquid solvent and before the active material particles are dispersed in the solvent. Also, such an order allows the threshold of percolation to be lowered to 0.3%-2.0%, with a minimal amount of conductive additive and thus a higher proportion of active material (and higher energy density). Makes it possible to manufacture conductive electrodes. Moreover, it was found that these observation results are applicable to all types of electrodes containing the active material particles, the conductive filaments and the electrolyte which have been examined so far. This is a very important and unexpected process requirement for preparing high performance alkali metal batteries with both high energy density and high power density.

A quasi-solid cathode, a porous separator, and a quasi-solid anode (similarly prepared but with artificial graphite particles as the anode active material) are then assembled together to form a unit cell, which is then A battery was formed by housing in a protective housing (laminated aluminum plastic pouch) having two protruding terminals. Batteries containing liquid or polymer gel electrolytes (1M) and quasi-solid polymer electrolytes (2.5M and 3.5M) were prepared and tested.

For comparison, a slurry coating and drying procedure was performed to produce a conventional electrode. Then, one anode and one cathode, and a separator disposed between the two electrodes are assembled and housed in an Al plastic laminate packaging container, after which a liquid electrolyte is injected to obtain lithium in the prior art. A battery cell was formed. The battery test results are summarized in Example 18.

Example 9: Electrochemical deposition of S on various web or paper structures for Li-S and Na-S batteries. Or Na-S cell). In this approach, an anode, an electrolyte and a layer of graphene sheets coagulated together (serving as a cathode layer) are positioned in an electrochemical deposition chamber. The equipment required is similar to electroplating systems well known in the art.

In a typical procedure, a metal polysulfide (M _x S _y ) is dissolved in a solvent (eg, a DOL/DME mixture in a volume ratio of 1:3 to 3:1) to form an electrolyte solution. Optionally, an amount of lithium salt can be added, but this is not necessary for external electrochemical deposition. A wide range of solvents is available for this purpose, and there is no theoretical limit as to what kind of solvent can be used. Any solvent can be used, provided there is some solubility of the metal polysulfide in this desired solvent. Greater solubility means that more sulfur can be drawn from the electrolyte.

The electrolyte is then injected into the chamber or reactor under a controlled dry atmosphere (eg, He or nitrogen gas). A metal foil can be used as the anode and a layer of porous graphene structure can be used as the cathode. Both are immersed in the electrolytic solution. This configuration constitutes an electrochemical deposition system. The step of electrochemically depositing nanoscale sulfur particles or coatings on the surface of the graphene sheet is performed at a current density preferably in the range of 1 mA/g to 10 A/g based on the layer weight of the porous graphene structure. Be seen.

Chemical reaction occurring in this reactor, the _{formula: (typically, z = 1~4) M x S} y → M x S y-z + zS can be represented by. Quite surprisingly, precipitated S is preferentially nucleated and grows on large graphene surfaces to form nanoscale coatings or nanoparticles. The S coating/particle coating thickness or particle size and amount can be controlled by specific surface area, electrochemical reaction current density, temperature and time. In general, lower current densities and lower reaction temperatures result in a more uniform distribution of S and the reaction is easier to control. Longer reaction times cause more S to be deposited on the graphene surface, and the reaction is stopped when the sulfur source is consumed or when the desired amount of S is deposited. These S-coated paper or web structures were then pulverized into fine particles for use as cathode active material in Li-S or Na-S cells.

Example 10: Chemical Reaction Induced Deposition of Sulfur Particles on Isolated Graphene Sheets Prior to Provision of the Cathode Layer To prepare S-graphene composites from isolated graphene oxide sheets, prior art Utilizing chemical vapor deposition (ie, these GO sheets were not packed into a monolithic structure of porous graphene prior to chemical deposition of S on the surface of the GO sheets). The procedure started by adding 0.58 g Na ₂ S to a flask filled with 25 ml distilled water to form a Na ₂ S solution. Then, 0.72 g of S element was suspended in a Na ₂ S solution and stirred with a magnetic stirrer at room temperature for about 2 hours. The color of the solution slowly changed to orange-yellow as the sulfur dissolved. After dissolution of sulfur, a sodium polysulfide (Na ₂ S _x ) solution was obtained (x=4-10).

Then, a graphene oxide-sulfur (GO-S) composite was prepared by a chemical vapor deposition method in an aqueous solution. First, 180 mg of graphite oxide was suspended in 180 ml of ultrapure water, and then ultrasonically treated at 50° C. for 5 hours to generate a stable graphene oxide (GO) dispersion liquid. Then, to the GO dispersion prepared as described above, the Na ₂ S _x solution was added in the presence of 5 wt% of the surfactant cetyltrimethylammonium bromide (CTAB), and the prepared GO/Na ₂ S _x mixture was added. The solution was sonicated for a further 2 hours, then 100 ml of a 2 mol/L HCOOH solution was titrated at a rate of 30-40 drops/min and stirred for 2 hours. Finally, the precipitate was filtered and washed several times with acetone and distilled water to remove salts and impurities. After filtration, the precipitate was dried in a drying oven at 50°C for 48 hours. This reaction, the _reaction: can be expressed by ^{S x 2- + 2H + → (} x-1) S + H 2 S.

Example 11: Deposition of Sulfur Particles and Activated Carbon (AC) Particles on Separated Graphene Sheets by Redox Chemistry Prior to Cathode Layer Preparation In this deposition process based on chemical reaction, sodium thiosulfate (Na) was used as the sulfur source. ₂ S ₂ O ₃ ) was used and HCl was used as the reaction. GO- water or an active carbon - water suspensions were prepared, then poured two reactants (HCl and _Na 2 _S 2 _{O 3)} to the suspension. The reaction was allowed to proceed at 25 to 75° C. for 1 to 3 hours to obtain a precipitate of S particles deposited on the surface of the GO sheet or in the pores of AC particles. This reaction can be represented by the following reaction:
2HCl+Na ₂ S ₂ O ₃ →2NaCl+S↓+SO ₂ ↑+H ₂ O

Example 12: a mixture of Preparation GO sheets and S of S / GO nanocomposite by solution deposition, are dispersed in a solvent (CS _2), to form a suspension. After careful stirring, the solvent was evaporated to obtain a solid nanocomposite, which was then crushed to obtain a nanocomposite powder. The primary sulfur particles in these nanocomposite particles have an average diameter of about 40-50 nm.

Example 13: Electrospun electroconductive web as a support layer for the anode Conductive web of filaments from PAA fibrils Poly(amic acid) (PAA) precursor for spinning, tetrahydrofuran/methanol (THF/MeOH, weight ratio 8) /2) in a mixed solvent of pyromellitic dianhydride (Aldrich) and 4,4'-oxydianiline (Aldrich). The PAA solution was spun into a fibrous web using an electrospinning apparatus. The device consisted of a 15 kV DC power supply with a positively charged capillary through which the polymer solution was extruded and a negatively charged drum to collect the fibers. At the same time, solvent removal from PAA and imidization were carried out by stepwise heat treatment under an air stream at 40° C. for 12 hours, 100° C. for 1 hour, 250° C. for 2 hours, and 350° C. for 1 hour. A thermoset polyimide (PI) web sample was carbonized at 1,000° C. to obtain carbonized nanofibers with an average fibril diameter of 67 nm. Such webs can be used as conductive substrates for anode active materials. We have observed that the implementation of a network of conductive nanofilaments at the anode of a Li-S cell can effectively suppress the initiation and growth of lithium dendrites, which can lead to internal short circuits. There is.

Example 14: Preparation of Pre-sodiumized Graphene Fluoride Sheet as Anode Active Material for Sodium Sulfur Batteries In order to produce graphene fluoride (GF), we have used several processes. However, only one process is described here as an example. In a typical procedure, highly exfoliated graphite (HEG) was prepared from the intercalated compound C ₂ F.xClF ₃ . HEG was further fluorinated with chlorine trifluoride vapor to produce fluorinated highly exfoliated graphite (FHEG). Pre-cooled liquid-filled pre-cooling ClF ₃ of 20~30mL Teflon reactor and cooled to liquid nitrogen temperature by closing the reactor. Then, 1 g or less of HEG was placed in a container having a hole for ClF ₃ gas to access, and the HEG was placed inside the reactor. Gray beige product of the approximate formula C _{2 F} are formed in 7-10 days.

Then, a small amount of FHEG (about 0.5 mg) was mixed with 20 to 30 mL of organic solvent (individually methanol and ethanol) and sonicated (280 W) for 30 minutes to produce a homogeneous yellowish dispersion. .. After removal of the solvent, the dispersion became a brownish powder. Graphene fluoride powder was mixed with a lithium tip in a liquid electrolyte to allow prelithiation before or after injection into the pores of the anode current collector.

Example 15: Graphene Reinforced Nano Silicon as Anode Active Material for Lithium Ion Sulfur Battery Graphene-encapsulated Si particles were loaded onto an Angstron Energy Co. (Dayton, Ohio, USA). Pure graphene sheets (as conductive filaments) are dispersed in a PC-DOL (50/50 ratio) mixture, followed by graphene wrapped Si particles (anode active material) in a mixed solvent at 60°C. A quasi-solid anode electrode was prepared by dissolving 3.5 M lithium hexafluorophosphate (LiPF ₆ ) in. Then, the DOL was removed to obtain a quasi-solid electrolyte containing about 5.0 M LiPF ₆ in PC. The maximum solubility of LiPF _{6 in} PC is known to be less than 3.0 M at room temperature, so this causes LiPF ₆ to become supersaturated.

Example 16: Graphene-reinforced tin oxide nanoparticles as anode active material Tin oxide (SnO ₂ ) nanoparticles were obtained by hydrolyzing SnCl ₄ .5H ₂ O with NaOH under control using the following procedure. It was _{SnCl 4 · 5H 2 O (0.95g} , 2.7m-mol) and NaOH (0.212g, 5.3m-mol) were each dissolved in distilled water 50 mL. The NaOH solution was added dropwise to the tin chloride solution at a rate of 1 mL/min with vigorous stirring. The solution was homogenized by sonication for 5 minutes. Then, the resulting hydrosol was reacted with the GO dispersion for 3 hours. A few drops of 0.1 M H ₂ SO ₄ were added to this mixed solution to aggregate the product. The precipitated solid was collected by centrifugation, washed with water and ethanol and dried under vacuum. The dried product was heat-treated under Ar atmosphere at 400° C. for 2 hours and used as an anode active material.

Example 17: Preparation of various battery cells and electrochemical testing For most of the anode and cathode active materials studied, lithium ion cells or lithium metal cells were prepared using both the method according to the invention and the conventional method. ..

In the conventional method, a typical anode composition is 85 wt% active material (eg, Si-coated graphene sheet), 7 wt% acetylene black (Super-P), and N-methyl-2-. 8% by weight polyvinylidene fluoride binder (PVDF, 5% by weight solids content) dissolved in pyrrolidinone (NMP). After coating the slurry on the Cu foil, the electrode was vacuum dried at 120° C. for 2 hours to remove the solvent. The method typically does not require or use a binder resin, reducing weight by 8% (reducing the amount of inactive material). The cathode layer is similarly prepared (using Al foil as the cathode current collector) using conventional slurry coating and drying procedures. The anode layer, separator layer (eg Celgard 2400 membrane) and cathode layer are then laminated together and housed in a plastic Al envelope. As an example, then, a mixture of ethylene carbonate (EC) and diethyl carbonate (DEC) (EC-DEC, 1: 1v / v) injecting 1M LiPF ₆ electrolyte solution dissolved in the cell. In some cells, ionic liquids were used as the liquid electrolyte. The cell assembly was formed in a glove box filled with argon.

The process of the present invention preferably assembles a quasi-solid polymer anode, a porous separator and a quasi-solid polymer cathode in a protective enclosure. The pouch was then sealed.

Cyclic voltammetry (CV) measurements were performed using an Arbin electrochemical workstation at a typical scan rate of 1 mV/s. Furthermore, the electrochemical performance of various cells was evaluated at constant current charge/discharge cycles at current densities of 50 mA/g to 10 A/g. A LAND multi-channel battery tester was used for the long-term cycle test.

Example 18: Typical Test Results For each sample, several current densities (representing charge/discharge rates) were imposed to determine the electrochemical response and a Ragone plot (power density vs. energy density) was constructed. It enables the calculation of the energy density and power density values required for. FIG. 6A shows a Ragone plot (weight power density vs. energy density) of a lithium-sulfur cell containing Li foil as an anode active material and carbon black-sulfur composite particles as a cathode active material. Three of the four data curves relate to cells prepared according to embodiments of the invention (using the sequence S1, S2 and S3 respectively), the other one is conventional slurry coating of electrodes (roll coating). ). Some important observations can be made from these data.

The weight energy density and power density of the lithium-ion battery cells prepared by the method according to the invention are significantly higher than those of the counterparts prepared by the conventional roll coating method (designated as "conventional"). From a cathode thickness of 150 μm (coated on a flat solid Al foil) to a thickness of 530 μm with quasi-solid polymer electrolyte, from 325 Wh/kg to 413 Wh/kg (S1), 425 Wh/kg (S1), 425 Wh/kg (S1), respectively. S2) and an increase in gravimetric energy density to 526 Wh/kg (S3) occur. Also, surprisingly, a cell containing a quasi-solid electrode according to the invention with a 3D network of electronic conduction paths (due to percolation of the conductive filaments) has a significantly higher energy density (FIG. 6(A)) and more stable cycling. The behavior (FIG. 6(B)) is provided.

These large differences cannot simply be attributed to increased electrode thickness and mass loading. These differences are due to the significantly higher active material mass loading (rather than just mass loading) and higher conductivity associated with cells according to the present invention, a reduction in the ratio of active material weight/volume of overhead (inactive) components, and Surprisingly good utilization of electrode active materials (most, if not all, due to higher conductivity and lack of dry pockets or ineffective spots in the electrode, especially under high charge/discharge rate conditions. S contributes to the lithium ion storage capacity).

FIG. 7( a) shows a Ragone plot (weight power density vs. weight energy density) of two cells, both containing graphene-supported S particles as cathode active material. Experimental data were obtained from Li-S battery cells prepared by the method according to the invention and battery cells prepared by conventional slurry coating of electrodes.

These data show that the gravimetric energy density and power density of the battery cells prepared by the method according to the invention are considerably higher than their counterparts prepared by the conventional method. Here too, the difference is significant. Conventionally made cells show a gravimetric energy density of 433 Wh/kg, whereas cells according to the invention provide an energy density of 603 Wh/kg (S3). The high power density of 1,887 W/kg is also unprecedented for lithium-sulfur batteries. The cell according to the invention also achieves a much more stable charge/discharge cycle behavior, as shown in FIG. 7(B).

These energy and power density differences are mainly due to the high active material mass loadings associated with cells according to the invention (greater than 25 mg/cm ^{2 for} anodes, greater than 45 mg/cm ^{2 for} cathodes) and high electrode conductivity. Reduction of the ratio of overhead (inactive) component to active material weight/volume and the ability of the method of the present invention to better utilize the active material particles (all particles reachable to the liquid electrolyte and fast ions and Electronic kinematics).

Reports of energy and power density by weight of active material alone on the Ragone plot, as many researchers have done, may not give a realistic picture of the performance of assembled supercapacitor cells. It would be important to point out. The weight of other device components must also be taken into account. These overhead components, including current collectors, electrolytes, separators, binders, connectors and packaging are non-active materials and do not contribute to charge storage. These components only add weight and volume to the device. Therefore, it is desirable to reduce the relative weight ratio of the overhead components and increase the proportion of active material. However, it was not possible to achieve this end using conventional battery manufacturing methods. The present invention overcomes this longstanding and most significant problem in the lithium battery art.

In commercially available lithium-ion batteries with electrode thickness of 100-200 μm, the weight ratio of anode active material (eg, graphite or carbon) in the lithium-ion battery is typically 12-17%, or cathode active material. The weight ratio (for inorganic materials such as LiMn ₂ O ₄ ) is between 22% and 41% or for organic or polymeric materials between 10% and 15%. Therefore, a factor of 3-4 is often used to extrapolate the energy density or power density of the device (cell) from the properties based solely on the active material weight. In most scientific papers, the properties reported are typically based solely on active material weight, and electrodes are typically very thin (<<100 μm and mostly <<50 μm). The active material weight is typically 5% to 10% of the total device weight, which is the actual cell (device) energy or power density obtained by dividing the corresponding active material weight base value by a factor of 10-20. Suggest that you can get After considering this factor, the properties reported in these papers do not appear to be better than those of commercial batteries. Therefore, one must be very careful in reading and interpreting the battery performance data reported in scientific papers and patent applications.

Claims (57)

(A) 30% by volume to 95% by volume of a sulfur-containing cathode active material, 5% by volume to 40% by volume of a first electrolyte containing an alkali salt and an ion conductive polymer dissolved or dispersed in a solvent, and A quasi-solid cathode containing from 01 vol% to about 30 vol% conductive additive, wherein the sulfur-containing cathode active material is sulfur, a metal-sulfur compound, a sulfur-carbon composite, a sulfur-graphene composite. , A sulfur-graphite composite, an organosulfur compound, a sulfur-polymer composite or a combination thereof, the conductive additive containing a conductive filament forms a 3D network of electronic conduction pathways, whereby The quasi-solid electrode has a conductivity of 10 ⁻⁶ S/cm to 300 S/cm;
(B) an anode,
(C) In an alkali metal-sulfur cell including an ion conductive membrane or a porous separator disposed between the anode and the quasi-solid cathode, the quasi-solid cathode has a thickness of 200 μm or more. Characteristic alkali metal-sulfur cell. The alkali metal-sulfur cell of claim 1, wherein the anode comprises 1.0 vol% to about 95 vol% anode active material, an alkali salt dissolved or dispersed in a solvent, and an ion-conducting polymer. Comprising a quasi-solid anode containing from 40% to 40% by volume of a second electrolyte and from 0.01% to about 30% by volume of a conductive additive, wherein the conductive additive containing conductive filaments is Alkali metal-sulfur cell, wherein the quasi-solid electrode has a conductivity of about 10 ⁻⁶ S/cm to about 300 S/cm, which forms a 3D network of electronic conduction paths. In the alkali metal-sulfur cell,
A) 1.0% by volume to 95% by volume of the anode active material, 5% by volume to 40% by volume of an electrolyte containing an alkali salt and an ion conductive polymer dissolved or dispersed in a solvent, and 0.01% by volume. A quasi-solid anode containing 30% by volume of a conductive additive, said conductive additive containing a conductive filament forming a 3D network of electronic conduction paths, whereby said quasi-solid electrode comprises A quasi-solid state anode having a conductivity of about 10 ⁻⁶ S/cm to about 300 S/cm,
B) a cathode containing a cathode active material selected from sulfur, metal-sulfur compounds, sulfur-carbon composites, sulfur-graphene composites, sulfur-graphite composites, organic sulfur compounds or sulfur-polymer composites;
(C) An alkali metal-sulfur cell comprising an ion conductive membrane or a porous separator disposed between the semi-solid anode and the cathode. The alkali metal-sulfur cell of claim 1, wherein the first electrolyte is poly(ethylene oxide) (PEO), polypropylene oxide (PPO), poly(acrylonitrile) having a molecular weight of less than 1×10 ⁶ g/mol. (PAN), poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride) (PVDF), polybis-methoxyethoxyethoxide-phosphazene, polyvinyl chloride, polydimethylsiloxane, poly(vinylidene fluoride)-hexafluoropropylene Alkali metal-sulfur cell, characterized in that it contains a quasi-solid polymer electrolyte containing an ion-conducting polymer selected from (PVDF-HFP), their sulfonated derivatives, sulfonated polymers or combinations thereof. The alkali metal-sulfur cell of claim 2, wherein the first electrolyte or the second electrolyte is poly(ethylene oxide) (PEO), polypropylene oxide (PPO) having a molecular weight of less than 1×10 ⁶ g/mol. ), poly(acrylonitrile) (PAN), poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride) (PVDF), polybis-methoxyethoxyethoxide-phosphazene, polyvinyl chloride, polydimethylsiloxane, poly(fluorinated) Vinylidene)-hexafluoropropylene (PVDF-HFP), alkali metal characterized by containing a quasi-solid polymer electrolyte containing an ion-conducting polymer selected from sulfonated derivatives thereof, sulfonated polymers or combinations thereof- Sulfur cell. The alkali metal-sulfur cell according to claim 3, wherein the electrolyte has poly(ethylene oxide) (PEO), polypropylene oxide (PPO), poly(acrylonitrile) (PAN) having a molecular weight of less than 1×10 ⁶ g/mol. , Poly(methylmethacrylate) (PMMA), poly(vinylidene fluoride) (PVDF), polybis-methoxyethoxyethoxide-phosphazene, polyvinyl chloride, polydimethylsiloxane, poly(vinylidene fluoride)-hexafluoropropylene (PVDF- HFP), sulfonated derivatives thereof, sulfonated polymers or quasi-solid polymer electrolytes containing ion-conducting polymers selected from combinations thereof, alkali metal-sulfur cells. The alkali metal-sulfur cell according to claim 1, wherein the ion conductive polymer is poly(perfluorosulfonic acid), sulfonated polytetrafluoroethylene, sulfonated perfluoroalkoxy derivative of polytetrafluoroethylene, sulfonated polysulfone, Sulfonated poly(ether ketone), Sulfonated poly(ether ether ketone), Sulfonated polystyrene, Sulfonated polyimide, Sulfonated styrene-butadiene copolymer, Sulfonated polychloro-trifluoroethylene (PCTFE), Sulfonated perfluoroethylene -Propylene copolymer (FEP), sulfonated ethylene-chlorotrifluoroethylene copolymer (ECTFE), sulfonated polyvinylidene fluoride (PVDF), sulfonated copolymer of polyvinylidene fluoride with hexafluoropropene and tetrafluoroethylene Being selected from the group consisting of a combination, a sulfonated copolymer of ethylene and tetrafluoroethylene (ETFE), a sulfonated polybenzimidazole (PBI), their chemical derivatives, copolymers, blends and combinations thereof. And an alkali metal-sulfur cell. The alkali metal-sulfur cell according to claim 2, wherein the ion conductive polymer is poly(perfluorosulfonic acid), sulfonated polytetrafluoroethylene, sulfonated perfluoroalkoxy derivative of polytetrafluoroethylene, sulfonated polysulfone, Sulfonated poly(ether ketone), Sulfonated poly(ether ether ketone), Sulfonated polystyrene, Sulfonated polyimide, Sulfonated styrene-butadiene copolymer, Sulfonated polychloro-trifluoroethylene (PCTFE), Sulfonated perfluoroethylene -Propylene copolymer (FEP), sulfonated ethylene-chlorotrifluoroethylene copolymer (ECTFE), sulfonated polyvinylidene fluoride (PVDF), sulfonated copolymer of polyvinylidene fluoride with hexafluoropropene and tetrafluoroethylene Be selected from the group consisting of: coalesce, sulfonated copolymer of ethylene and tetrafluoroethylene (ETFE), sulfonated polybenzimidazole (PBI), their chemical derivatives, copolymers, blends and combinations thereof. And an alkali metal-sulfur cell. The alkali metal-sulfur cell according to claim 3, wherein the ion conductive polymer is poly(perfluorosulfonic acid), sulfonated polytetrafluoroethylene, sulfonated perfluoroalkoxy derivative of polytetrafluoroethylene, sulfonated polysulfone, Sulfonated poly(ether ketone), Sulfonated poly(ether ether ketone), Sulfonated polystyrene, Sulfonated polyimide, Sulfonated styrene-butadiene copolymer, Sulfonated polychloro-trifluoroethylene (PCTFE), Sulfonated perfluoroethylene -Propylene copolymer (FEP), sulfonated ethylene-chlorotrifluoroethylene copolymer (ECTFE), sulfonated polyvinylidene fluoride (PVDF), sulfonated copolymer of polyvinylidene fluoride with hexafluoropropene and tetrafluoroethylene Being selected from the group consisting of a combination, a sulfonated copolymer of ethylene and tetrafluoroethylene (ETFE), a sulfonated polybenzimidazole (PBI), their chemical derivatives, copolymers, blends and combinations thereof. And an alkali metal-sulfur cell. The alkali metal-sulfur cell according to claim 1, wherein the conductive filament is carbon fiber, graphite fiber, carbon nanofiber, graphite nanofiber, carbon nanotube, needle coke, carbon whisker, conductive polymer fiber, conductive material. Alkali metal-sulfur cell, characterized in that it is selected from coated fibers, metal nanowires, metal fibers, metal wires, graphene sheets, expanded graphite platelets, combinations thereof or combinations thereof with non-filamentary conductive particles. The alkali metal-sulfur cell of claim 1, wherein the ion conductive polymer does not form a matrix within the quasi-solid cathode. The alkali metal-sulfur cell of claim 3, wherein the ion conducting polymer does not form a matrix within the quasi-solid anode. The alkali metal-sulfur cell according to claim 1, wherein the electrode maintains a conductivity of 10 ⁻³ S/cm to 10 S/cm. The alkali metal-sulfur cell according to claim 1, wherein the quasi-solid cathode contains 0.1% to 20% by volume of a conductive additive. The alkali metal-sulfur cell according to claim 1, wherein the quasi-solid cathode contains 1% to 10% by volume of a conductive additive. The alkali metal-sulfur cell according to claim 1, wherein the amount of the active material is 40% by volume to 90% by volume of the electrode material. The alkali metal-sulfur cell according to claim 1, wherein the amount of the active material is 50% by volume to 85% by volume of the electrode material. The alkali metal-sulfur cell according to claim 1, wherein the first electrolyte is in a supersaturated state. The alkali metal-sulfur cell according to claim 2, wherein the first electrolyte or the second electrolyte is in a supersaturated state. The alkali metal-sulfur cell according to claim 1, wherein the solvent is selected from water, an organic solvent, an ionic liquid, or a mixture of an organic solvent and an ionic liquid. The alkali metal-sulfur cell according to claim 2, wherein the first electrolyte or the second electrolyte contains a solvent selected from water, an organic solvent, an ionic liquid, or a mixture of an organic solvent and an ionic liquid. An alkali metal-sulfur cell characterized by the following. The alkali metal-sulfur cell of claim 1, wherein the anode is
(A) particles of lithium metal or lithium metal alloy, a thin film or foil,
(B) natural graphite particles, artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle cokes, carbon nanotubes, carbon nanofibers, carbon fibers and graphite fibers,
(C) Silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), nickel (Ni), cobalt ( Co), manganese (Mn), titanium (Ti), iron (Fe) and cadmium (Cd),
(D) An alloy or intermetallic compound of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al or Cd and another element, which is stoichiometric or non-stoichiometric. Inter-compound,
(E) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ni, Co, Ti, Mn or Cd, and oxides, carbides, nitrides, sulfides, phosphorus of mixtures or composites thereof. And selenides and tellurides,
(F) their pre-lithiated versions,
(G) a pre-lithiated graphene sheet,
An alkali metal-sulfur cell, comprising an anode active material selected from the group consisting of a combination thereof. 23. The alkali metal-sulfur cell of claim 22, wherein the pre-lithiated graphene sheet is pure graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide. , Hydrogenated graphene, nitrogenated graphene, boron-doped graphene, nitrogen-doped graphene, chemically functionalized graphene, physically or chemically activated or etched versions thereof, or pre-lithiated versions thereof Alkali metal-sulfur cell characterized in that it is selected from different versions. The alkali metal-sulfur cell according to claim 1, which is a sodium metal-sulfur cell or a sodium ion sulfur cell, and the anode is petroleum coke, amorphous carbon, activated carbon, hard carbon, soft carbon, template carbon, Hollow carbon nanowires, hollow carbon spheres, titanates, NaTi ₂ (PO ₄ ) ₃ , Na ₂ Ti ₃ O ₇ , Na ₂ C ₈ H ₄ O ₄ , Na ₂ TP, Na _x TiO ₂ (x=0.2). _{~1.0), Na 2 C 8 H} 4 O 4, the carboxylic acid-based _{material, C 8 H 4 Na 2 O} 4, C 8 H 6 O 4, C 8 H 5 NaO 4, C 8 Na 2 F 4 An anode active material containing a sodium metal or an alkaline intercalation compound selected from O ₄ , C ₁₀ H ₂ Na ₄ O ₈ , C ₁₄ H ₄ O ₆ , C ₁₄ H ₄ Na ₄ O ₈ or a combination thereof. An alkali metal-sulfur cell characterized by containing. The alkali metal-sulfur cell according to claim 2, which is a sodium-sulfur cell or a sodium-ion sulfur cell, and the anode is
a) sodium metal or sodium metal alloy particles, foil or thin film,
b) natural graphite particles, artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle cokes, carbon nanotubes, carbon nanofibers, carbon fibers and graphite fibers,
c) Sodium-doped silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), titanium (Ti). ), cobalt (Co), nickel (Ni), manganese (Mn), cadmium (Cd) and mixtures thereof,
d) a sodium-containing alloy or intermetallic compound of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Co, Ni, Mn, Cd and mixtures thereof,
e) Sodium-containing oxides, carbides, nitrides, sulfides of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ti, Co, Ni, Mn, Cd and mixtures or composites thereof, Phosphides, selenides, tellurides or antimonides,
f) a sodium salt,
g) a graphene sheet preloaded with sodium ions,
An alkali metal-sulfur cell, comprising an anode active material selected from the group consisting of a combination thereof. The alkali metal-sulfur cell according to claim 1, wherein the cathode active material is
A) Nanostructured or porous selected from soft carbon, hard carbon, polymeric carbon or carbonized resin, mesophase carbon, coke, carbonized pitch, carbon black, activated carbon, nanocell carbon foam or partially graphitized carbon. Irregular carbon material,
B) Nano-graphene platelets selected from single-layer graphene sheets or multilayer graphene platelets,
C) a carbon nanotube selected from single-walled carbon nanotubes or multi-walled carbon nanotubes,
D) Carbon nanofibers, nanowires, metal oxide nanowires or fibers, conductive polymer nanofibers or combinations thereof,
E) a carbonyl-containing organic or polymer molecule,
F) a functional material containing a carbonyl group, a carboxyl group or an amine group for reversibly capturing sulfur,
An alkali metal-sulfur cell characterized in that it is supported by a functionalized material or a nanostructured material selected from the group consisting of a combination thereof. The alkali metal-sulfur battery according to claim 1, wherein the first electrolyte is 1,3-dioxolane (DOL), 1,2-dimethoxyethane (DME), tetraethylene glycol dimethyl ether (TEGDME), poly(ethylene). Glycol) dimethyl ether (PEGDME), diethylene glycol dibutyl ether (DEGDBE), 2-ethoxyethyl ether (EEE), sulfone, sulfolane, ethylene carbonate (EC), dimethyl carbonate (DMC), methyl ethyl carbonate (MEC), diethyl carbonate (DEC). ), ethyl propionate, methyl propionate, propylene carbonate (PC), γ-butyrolactone (γ-BL), acetonitrile (AN), ethyl acetate (EA), propyl formate (PF), methyl formate (MF), toluene, Characterized by containing a liquid organic solvent selected from the group consisting of xylene, methyl acetate (MA), fluoroethylene carbonate (FEC), vinylene carbonate (VC), allylethyl carbonate (AEC), hydrofluoroether and combinations thereof. And how to. The alkali metal-sulfur battery according to claim 1, wherein the first electrolyte is lithium perchlorate (LiClO ₄ ), lithium hexafluorophosphate (LiPF ₆ ), lithium borofluoride (LiBF ₄ ), and hexafluoride. Lithium arsenate (LiAsF ₆ ), lithium trifluoro-metasulfonate (LiCF ₃ SO ₃ ), lithium bis-trifluoromethylsulfonylimide (LiN(CF ₃ SO ₂ ) ₂ ), lithium bis(oxalate)borate (LiBOB) , Lithium oxalyl difluoroborate (LiBF ₂ C ₂ O ₄ ), lithium oxalyl difluoroborate (LiBF ₂ C ₂ O ₄ ), lithium nitrate (LiNO ₃ ), Li-fluoroalkyl phosphate (LiPF3(CF ₂ CF ₃ ) ₃ ), lithium bisperfluoroethisulfonylimide (LiBETI), sodium perchlorate (NaClO ₄ ), potassium perchlorate (KClO ₄ ), sodium hexafluorophosphate (NaPF ₆ ), potassium hexafluorophosphate (KPF _{6 ).} ), sodium borofluoride (NaBF ₄ ), potassium borofluoride (KBF ₄ ), sodium hexafluoroarsenate, potassium hexafluoroarsenate, sodium trifluoro-metasulfonate (NaCF ₃ SO ₃ ), trifluoro-metasulfonic acid potassium _(KCF 3 _SO 3), bis - trifluoromethyl sulfonyl imide sodium _{(NaN (CF 3 SO 2)} 2), trifluoromethane sulfonimide sodium (NaTFSI), bis - trifluoromethyl sulfonyl imide potassium (KN _(CF 3 SO ₂ ) A method comprising containing an alkali metal salt selected from ₂ ) or a combination thereof. The alkali metal-sulfur battery according to claim 1, wherein the first electrolyte is tetra-alkylammonium, di-, tri- or tetra-alkylimidazolium, alkylpyridinium, dialkyl-pyrrolidinium, dialkylpiperidinium, tetra. A method comprising the inclusion of an ionic liquid solvent selected from room temperature ionic liquids having a cation selected from alkylphosphonium, trialkylsulfonium or combinations thereof. The alkaline metal-sulfur battery according to claim 29, wherein the ionic liquid solvent is BF ₄ ⁻ , B(CN) ₄ ⁻ , CH ₃ BF ₃ ⁻ , CH ₂ CHBF ₃ ⁻ , CF ₃ BF ₃ ⁻ , C _2. F ₅ BF ₃ ⁻ , n−C ₃ F ₇ BF ₃ ⁻ , n−C ₄ F ₉ BF ₃ ⁻ , PF ₆ ⁻ , CF ₃ CO ₂ ⁻ , CF ₃ SO ₃ ⁻ , N(SO ₂ CF ₃ ) _{2 ^{-, N (COCF 3) (}} SO 2 CF 3) -, N (SO 2 F) 2 -, N (CN) 2 -, C (CN) 3 -, SCN -, SeCN -, CuCl 2 -, AlCl 4 ^-, F (HF) _2.3 ^- wherein the chosen from room temperature ionic liquid having an anion selected from or a combination thereof. The alkali metal cell of claim 1, wherein the cathode active material comprises an electrode active material mass loading of greater than 15 mg/cm ² . The alkali metal cell of claim 2, wherein the anode active material comprises an electrode active material mass loading of greater than 20 mg/cm ² . The alkali metal cell of claim 1, wherein the cathode active material comprises an electrode active material mass loading of greater than 30 mg/cm ² . In a method of preparing an alkali metal-sulfur cell having a quasi-solid electrode,
(A) combining a quantity of cathode active material, a quantity of electrolyte, and a conductive additive to form a deformable and conductive cathode material, wherein the cathode active material is sulfur, metal. A sulfur-containing material selected from a sulfur compound, a sulfur-carbon composite, a sulfur-graphene composite, a sulfur-graphite composite, an organic sulfur compound, a sulfur-polymer composite or a combination thereof, and a conductive filament The conductive additive containing forms a 3D network of electron conducting pathways, and the electrolyte contains an alkali salt and an ion conducting polymer dissolved or dispersed in a solvent, and
(B) forming the cathode material into a quasi-solid cathode, wherein the 3D network of electron conduction paths is uninterrupted so that the cathode maintains a conductivity of 10 ⁻⁶ S/cm or more. The step of transforming the cathode material into an electrode shape; (c) forming the anode;
(D) combining the quasi-solid cathode and the anode to form an alkali metal-sulfur cell. 35. The method of claim 34, wherein the quasi-solid cathode comprises 30% to 95% by volume of the cathode active material, 5% to 40% by volume of the electrolyte, and 0.01% to 30% by volume of the electrolyte. A method comprising containing a conductive additive. 35. The method of claim 34, wherein the electrolyte is poly(ethylene oxide) (PEO), polypropylene oxide (PPO), poly(acrylonitrile) (PAN), poly(methyl) having a molecular weight of less than 1 x 10< ⁶ > g/mol. Methacrylate) (PMMA), poly(vinylidene fluoride) (PVDF), polybis-methoxyethoxyethoxide-phosphazene, polyvinyl chloride, polydimethylsiloxane, poly(vinylidene fluoride)-hexafluoropropylene (PVDF-HFP), and the like. A quasi-solid polymer electrolyte containing an ion-conducting polymer selected from sulfonated derivatives, sulfonated polymers or combinations thereof. 35. The method of claim 34, wherein the ion conductive polymer is poly(perfluorosulfonic acid), sulfonated polytetrafluoroethylene, sulfonated perfluoroalkoxy derivative of polytetrafluoroethylene, sulfonated polysulfone, sulfonated poly( Ether ketone), sulfonated poly(ether ether ketone), sulfonated polystyrene, sulfonated polyimide, sulfonated styrene-butadiene copolymer, sulfonated polychloro-trifluoroethylene (PCTFE), sulfonated perfluoroethylene-propylene copolymer Polymer (FEP), sulfonated ethylene-chlorotrifluoroethylene copolymer (ECTFE), sulfonated polyvinylidene fluoride (PVDF), sulfonated copolymer of polyvinylidene fluoride with hexafluoropropene and tetrafluoroethylene, ethylene and Characterized by being selected from the group consisting of sulfonated copolymers with tetrafluoroethylene (ETFE), sulfonated polybenzimidazoles (PBI), their chemical derivatives, copolymers, blends and combinations thereof. Method. The method according to claim 34, wherein the conductive filament is carbon fiber, graphite fiber, carbon nanofiber, graphite nanofiber, carbon nanotube, needle coke, carbon whisker, conductive polymer fiber, conductive material-coated fiber, metal. A method characterized by being selected from nanowires, metal fibers, metal wires, graphene sheets, expanded graphite platelets, combinations thereof or combinations thereof with non-filamentary conductive particles. 35. The method of claim 34, wherein the ion conducting polymer does not form a matrix within the quasi-solid cathode. 35. The method of claim 34, wherein the electrode maintains a conductivity of ^10-3 S/cm to 10 S/cm. 35. The method of claim 34, wherein the quasi-solid cathode contains 0.1% to 20% by volume conductive additive. 35. The method of claim 34, wherein the quasi-solid cathode contains 1% to 10% by volume conductive additive. 35. The method of claim 34, wherein the amount of cathode active material is 40% to 90% by volume of the cathode material. 35. The method of claim 34, wherein the amount of active material is about 50% to about 85% by volume of the cathode material. 35. The method of claim 34, wherein the combining step comprises dissolving the alkali metal salt and the ion-conducting polymer in the liquid solvent of the suspension prior to adding the cathode active material to the suspension. Before, comprising dispersing the conductive filaments in a liquid solvent to form a homogeneous suspension. 35. The method of claim 34, wherein the step of combining the cathode materials and forming a quasi-solid cathode comprises dissolving a lithium salt or sodium salt and the polymer in a liquid solvent to produce a first salt/polymer concentration. A second salt/polymer higher than the first concentration and higher than 2.5M to form an electrolyte having and then to remove a portion of the liquid solvent to increase the salt/polymer concentration. A method comprising obtaining a quasi-solid polymer electrolyte having a concentration. 47. The method of claim 46, wherein the removing step does not cause precipitation or crystallization of the salt or the polymer, and the electrolyte is supersaturated. 47. The method of claim 46, wherein the liquid solvent contains at least a mixture of a first liquid solvent and a second liquid solvent, and the first liquid solvent is more volatile than the second liquid solvent. The method of claim 3, wherein the step of removing a portion of the liquid solvent is highly reactive and comprises removing the first liquid solvent. 35. The method of claim 34, wherein the step of forming the anode comprises: (A) combining a quantity of anode active material, a quantity of electrolyte, and a conductive additive with a deformable and conductive anode. Forming a material, wherein the conductive additive containing a conductive filament forms a 3D network of electronic conduction paths, and the electrolyte is dissolved or dispersed in a solvent, an alkali salt and an ion conductive polymer. And (B) forming the deformable and conductive anode material into a quasi-solid state anode, the electron being maintained so that the anode maintains a conductivity of 10 ⁻⁶ S/cm or more. Transforming the deformable and conductive anode material into an electrode shape without interrupting the 3D network of conduction paths. 35. The method according to claim 34, wherein the solvent is selected from water, an organic solvent, an ionic liquid or a mixture of an organic solvent and an ionic liquid. 35. The method of claim 34, wherein the alkali metal-sulfur cell is a lithium ion sulfur cell and the anode is
(A) particles of lithium metal or lithium metal alloy,
(B) natural graphite particles, artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle cokes, carbon nanotubes, carbon nanofibers, carbon fibers and graphite fibers,
(C) Silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), nickel (Ni), cobalt ( Co), manganese (Mn), titanium (Ti), iron (Fe) and cadmium (Cd),
(D) An alloy or intermetallic compound of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al or Cd and another element, which is stoichiometric or non-stoichiometric. Inter-compound,
(E) Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ni, Co, Ti, Mn or Cd, and oxides, carbides, nitrides, sulfides, phosphorus of mixtures or composites thereof. And selenides and tellurides,
(F) their pre-lithiated versions,
(G) a pre-lithiated graphene sheet,
A method of including an anode active material selected from the group consisting of a combination thereof. 52. The method of claim 51, wherein the pre-lithiated graphene sheet comprises pure graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, graphene hydride. Selected from nitrogenated graphene, boron-doped graphene, nitrogen-doped graphene, chemically functionalized graphene, physically or chemically activated or etched versions thereof, or prelithiated versions of combinations thereof. A method characterized by being performed. 35. The method of claim 34, wherein the alkali metal-sulfur cell is a sodium ion sulfur cell and the anode is petroleum coke, carbon black, amorphous carbon, activated carbon, hard carbon, soft carbon, template carbon. , Hollow carbon nanowires, hollow carbon spheres, titanates, NaTi ₂ (PO ₄ ) ₃ , Na ₂ Ti ₃ O ₇ , Na ₂ C ₈ H ₄ O ₄ , Na ₂ TP, Na _x TiO ₂ (x=0. _{2~1.0), Na 2 C 8 H} 4 O 4, the carboxylic acid-based _{material, C 8 H 4 Na 2 O} 4, C 8 H 6 O 4, C 8 H 5 NaO 4, C 8 Na 2 F Contains an anode active material containing an alkaline intercalation compound selected from ₄ O ₄ , C ₁₀ H ₂ Na ₄ O ₈ , C ₁₄ H ₄ O ₆ , C ₁₄ H ₄ Na ₄ O ₈ or combinations thereof. A method characterized by that. 35. The method of claim 34, wherein the alkali metal-sulfur cell is a sodium ion sulfur cell and the active material is
a) particles of sodium metal or sodium metal alloy,
b) natural graphite particles, artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle cokes, carbon nanotubes, carbon nanofibers, carbon fibers and graphite fibers,
c) Sodium-doped silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), titanium (Ti). ), cobalt (Co), nickel (Ni), manganese (Mn), cadmium (Cd) and mixtures thereof,
d) a sodium-containing alloy or intermetallic compound of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Co, Ni, Mn, Cd and mixtures thereof,
e) Sodium-containing oxides, carbides, nitrides, sulfides of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ti, Co, Ni, Mn, Cd and mixtures or composites thereof, Phosphides, selenides, tellurides or antimonides,
f) a sodium salt,
g) a graphene sheet preloaded with sodium ions,
A method comprising: an anode active material selected from the group consisting of a combination thereof. The method of claim 34, wherein the cathode active material, wherein the forming the electrode active material mass loading of 15 mg / cm ² greater. The method of claim 34, wherein the cathode active material, wherein the forming the electrode active material mass loading of 25 mg / cm ² greater. The method of claim 34, wherein the cathode active material, wherein the forming the electrode active material mass loading of 45 mg / cm ² greater.

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