CN106299467A - Composite solid electrolyte and flexible all-solid-state battery and preparation method, wearable electronic - Google Patents

Abstract

The invention proposes a composite solid electrolyte and a preparation method thereof, a flexible all-solid-state battery and a preparation method thereof, and a wearable electronic device. The composite solid electrolyte contains: a ceramic-based solid electrolyte and a first polymer-based solid electrolyte; wherein, based on the total weight of the composite solid electrolyte, the content of the ceramic-based solid electrolyte is 20-90% by weight. The composite solid electrolyte proposed in the present invention has good mechanical properties, high ion conductivity at room temperature, good thermal stability and electrochemical stability, high safety, can effectively prevent penetration by lithium dendrites, and A good interfacial contact with the composite positive electrode is formed, so that a flexible all-solid-state battery with high area specific capacity and energy density, low battery internal resistance, high flexibility, and bending and cutting without affecting the use can be obtained.

Description

Composite solid-state electrolyte and flexible all-solid-state battery and preparation method, wearable electronics equipment

technical field

The present invention relates to the technical field of lithium-ion batteries. Specifically, the present invention relates to a composite solid-state electrolyte and a preparation method thereof, a flexible all-solid-state battery and a preparation method thereof, and wearable electronic devices.

Background technique

At present, commercial lithium-ion batteries mostly use liquid electrolyte as the conduction medium for lithium ions between the positive and negative electrodes. Flammability and explosiveness have brought great safety hazards to the large-scale application of lithium-ion batteries.

In view of the above problems, it is the best solution to prepare all-solid-state lithium-ion batteries by using solid electrolytes instead of traditional electrolytes. The all-solid-state lithium-ion battery can prevent safety accidents such as liquid leakage and explosion, and at the same time, it can meet many harsh environmental requirements and use conditions. However, the design of the all-solid-state battery structure is still a difficult problem. The design of the composite cathode and the optimization of the interface between the cathode and the solid-state electrolyte are all problems that need to be solved urgently.

Contents of the invention

The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

The present invention has been accomplished based on the following findings of the inventors:

The inventors found during the research process that solid electrolyte materials can be divided into ceramic-based solid electrolyte materials and polymer-based solid electrolyte materials. Among them, the ceramic-based solid electrolyte material has high lithium ion conductivity at room temperature, and has good thermal and electrochemical stability, but it is difficult to form a good contact interface with the positive electrode, so that the assembled all-solid lithium ion The internal resistance of the battery is large; while the polymer-based solid electrolyte material can form a good contact interface with the positive electrode, but its mechanical strength is poor, and it may be penetrated by lithium dendrites.

After in-depth research, the inventors of the present invention found that the solid-state electrolyte is mainly made of ceramic-based solid-state electrolyte, which has high mechanical strength, is non-flammable and non-explosive, and has high safety; at the same time, a certain proportion of polymer-based electrolyte is added to the composite positive electrode and solid-state electrolyte The material can improve the ion transport performance of the composite positive electrode and the interface between the composite positive electrode and the solid electrolyte, and can also make the all-solid-state lithium-ion battery have a certain flexibility, and bending or cutting it will not affect the use of the all-solid-state battery.

In view of this, an object of the present invention is to propose a kind of having good mechanical properties, high ionic conductivity at room temperature, excellent area specific capacity, excellent energy density, good thermal stability, electrochemical stability under high temperature, and can Bending and cutting flexible all-solid-state batteries.

In the first aspect of the present invention, the present invention proposes a composite solid electrolyte. According to an embodiment of the present invention, the composite solid electrolyte contains: a ceramic-based solid electrolyte; and a first polymer-based solid electrolyte; wherein, based on the total weight of the composite solid electrolyte, the content of the ceramic-based solid electrolyte is 20 ~90% by weight; optionally, based on the total weight of the composite solid electrolyte, the content of the ceramic-based solid electrolyte is 40-80% by weight, and the content of the first polymer-based solid electrolyte is 20-60% by weight %.

The inventors of the present invention have found through long-term research that in the composite all-solid electrolyte with ceramic-based solid electrolyte as the main body, the mechanical properties can be significantly improved after the polymer-based solid electrolyte is added, and lithium dendrites can be effectively prevented from breaking through. At the same time, the composite all-solid electrolyte has certain flexibility and can also form a good interface with the composite positive electrode.

The inventors of the present invention conducted in-depth research and found that when the content of the ceramic-based solid electrolyte is 20-90% by weight of the total weight of the composite solid electrolyte, it can simultaneously ensure that the composite solid electrolyte has good mechanical properties and forms a good interface with the composite positive electrode , it is further flexible, and can be bent and cut without affecting the performance. Specifically, when the content of the ceramic-based solid electrolyte is 40 to 80% by weight and the content of the first polymer-based solid electrolyte is 20 to 60% by weight, the composite solid electrolyte can further have high mechanical strength and a good interface at the same time, and More excellent flexibility, can be bent at will.

The inventors unexpectedly found that the composite solid electrolyte of the embodiment of the present invention has good mechanical properties, high ionic conductivity at room temperature, good thermal stability and electrochemical stability, and can effectively prevent lithium dendrites from being penetrated. It is transparent, and also forms a good interface contact with the composite positive electrode, which has high safety.

In addition, the composite solid electrolyte according to the above embodiments of the present invention may also have the following additional technical features:

According to an embodiment of the present invention, the ceramic-based solid electrolyte includes at least one selected from lithium lanthanum zirconium oxide, lithium lanthanum titanium oxide, lithium titanium aluminum phosphate, and lithium germanium aluminum phosphate. The inventors of the present invention have found through research that lithium lanthanum zirconium oxide has a cubic garnet structure, has high room temperature ionic conductivity and electrochemical stability, and can optimize and improve the interface contact between the electrode and the electrolyte; The grain conductivity at room temperature is very high, and its conductivity is closest to the commercial level; while lithium titanium aluminum phosphate belongs to the trigonal crystal system, and has a high room temperature ionic conductivity, which is close to the level of commercial electrolytes.

Therefore, the ceramic-based solid electrolyte of the embodiment of the present invention has high ionic conductivity at room temperature, and has good thermal stability and electrochemical stability, and high mechanical properties can also be prepared without high temperature sintering treatment. All solid battery.

According to an embodiment of the present invention, the first polymer-based solid-state electrolyte includes: a first lithium salt, and the lithium salt includes lithium perchlorate, lithium ammonium trifluoromethanesulfonate, lithium hexafluorophosphate, and lithium tetrafluoroborate. and at least one of lithium diacetate borate; and a first macromolecular matrix, said macromolecular matrix comprising polyethylene oxide or its modification, polymethyl methacrylate or its modification, polyvinylidene fluoride At least one of polyacrylonitrile or its modified product and epichlorohydrin rubber or its modified product.

The inventors of the present invention have found through research that the polymer solid-based electrolyte has high energy density, is easy to manufacture, is safe and reliable, and is flexible in design, and a good contact interface can be formed between the polymer material and the composite positive electrode. At the same time, the above-mentioned polymer matrix The toughness is high, and the flexibility of the formed composite solid electrolyte sheet is improved. Moreover, adding lithium salt to the polymer matrix can improve the ion transport performance of the polymer solid-based electrolyte and enhance the mechanical strength of the polymer matrix.

Therefore, the polymer-based solid electrolyte of the embodiment of the present invention has high toughness, and the mechanical properties and flexibility of the solid electrolyte combined with the ceramic-based solid electrolyte are significantly improved, and at the same time, a good contact interface is formed with the positive electrode. , thereby reducing the internal resistance of the all-solid-state battery.

In the second aspect of the present invention, the present invention proposes a flexible all-solid-state battery. According to an embodiment of the present invention, the flexible all-solid-state battery contains the above-mentioned composite solid-state electrolyte. Those skilled in the art can understand that the flexible all-solid-state battery may also contain other necessary components, such as positive electrodes, negative electrodes, etc., which will not be repeated here.

The inventor unexpectedly found that the flexible all-solid-state battery of the embodiment of the present invention can be used at high temperature, has high mechanical strength, good safety performance, excellent area specific capacity and energy density, and the internal resistance of the battery is small, and its High flexibility, can be bent and cut without affecting the use of all-solid-state batteries. Those skilled in the art can understand that the features and advantages described above for the composite solid-state electrolyte are still applicable to the flexible all-solid-state battery, and will not be repeated here.

In addition, the flexible all-solid-state battery according to the above-mentioned embodiments of the present invention may also have the following additional technical features:

According to an embodiment of the present invention, the flexible all-solid-state battery also contains a composite positive electrode and a negative electrode; based on the total weight of the composite positive electrode, the composite positive electrode includes: a positive electrode active material, the content of which is 40-90% by weight, preferably, 50-75% by weight; the second polymer-based solid electrolyte, the content is 5-40% by weight, preferably 20% by weight; and the conductive additive, the content is 5-30% by weight.

The inventors unexpectedly found that adding a certain proportion of polymer-based solid electrolyte to the composite positive electrode can improve the ion transport performance of the composite positive electrode, as well as the interfacial contact between the composite positive electrode and the solid electrolyte, and make the composite positive electrode also have certain flexibility. Therefore, using the composite positive electrode of the embodiment of the present invention can not only improve ion transport, but also improve electronic conductivity, have good interface contact with the solid electrolyte, and have flexibility, so that the electrical performance of the all-solid-state battery can be improved. Internal resistance is reduced and flexibility is increased.

According to an embodiment of the present invention, the positive electrode active material includes at least one selected from lithium cobalt oxide, lithium manganese oxide, lithium iron phosphate, and nickel-cobalt-manganese ternary materials. Therefore, using the positive electrode active material of the embodiment of the present invention can make the composite positive electrode have high electrochemical activity, charge and discharge performance, and electrochemical stability, thereby increasing the stability and safety of the all-solid-state battery.

According to an embodiment of the present invention, the second polymer-based solid-state electrolyte contains: a second lithium salt, the lithium salt includes lithium perchlorate, lithium ammonium trifluoromethanesulfonate, lithium hexafluorophosphate, lithium tetrafluoroborate and at least one of lithium diacetate borate; and a second polymer matrix, said polymer matrix comprising polyethylene oxide or its modification, polymethyl methacrylate or its modification, polyvinylidene fluoride At least one of polyacrylonitrile or its modified product and epichlorohydrin rubber or its modified product. Therefore, the polymer-based solid electrolyte of the embodiment of the present invention has high toughness, improves the ion transport channel for the composite positive electrode, thereby increasing the ion transport property of the composite positive electrode, and can also increase the interaction between the composite positive electrode and the composite solid electrolyte. Contact the interface, thereby reducing the internal resistance of the all-solid-state battery and improving the electrochemical activity of the all-solid-state battery.

According to an embodiment of the present invention, the conductive additives include indium tin oxide, indium oxide, tin dioxide, zinc oxide, nickel oxide, ferric oxide, conductive carbon black, conductive graphite, carbon nanotubes, graphene , at least one of carbon fiber and acetylene. Therefore, using the conductive additive of the embodiment of the present invention provides an electron transport channel for the composite positive electrode, thereby improving the electronic conductivity of the composite positive electrode and further improving the electrochemical performance of the all-solid-state battery.

According to an embodiment of the present invention, the negative electrode includes lithium sheet, graphitized material, amorphous carbon, lithium titanate, titanium oxide, silicon, germanium, tin, antimony, tin oxide, silicon oxide, iron oxide, oxide At least one of cobalt, nickel oxide, molybdenum oxide, and copper oxide. Therefore, using the negative electrode of the embodiment of the present invention can improve the electrochemical performance, stability and safety of the all-solid-state battery.

In the third aspect of the present invention, the present invention proposes a method for preparing a composite solid electrolyte.

According to an embodiment of the present invention, the method includes: mixing a ceramic-based solid electrolyte and a first polymer-based solid electrolyte according to a predetermined ratio, so as to obtain the composite solid electrolyte.

The inventor unexpectedly found that the preparation method of the composite solid electrolyte according to the embodiment of the present invention is simple, the process conditions are mild, no complicated equipment is required, and the preparation cycle is short, and its raw material sources are extensive, which is conducive to large-scale semi-continuous production and manufacturing. Those skilled in the art can understand that the features and advantages described above for the composite solid electrolyte are still applicable to the preparation method of the composite solid electrolyte, and will not be repeated here.

In addition, the preparation method according to the above-mentioned embodiments of the present invention may also have the following additional technical features:

According to an embodiment of the present invention, the method includes: first mixing the ceramic-based solid electrolyte, the first polymer matrix and the first lithium salt in an organic medium; wherein the organic medium is the polymer matrix The good solvent includes at least one selected from acetonitrile, acetone, butanone, dimethylformamide and tetrahydrofuran; and the time for the first mixing is 5-48 hours, preferably 12-24 hours.

Thus, using the preparation method of the composite solid electrolyte of the embodiment of the present invention, the ceramic-based and polymer-based solid electrolytes are fully dissolved and mixed in the organic medium, thereby obtaining a uniform composite solid electrolyte slurry, and further forming The final composite solid electrolyte layer is denser and has higher mechanical properties, while maintaining toughness.

In the fourth aspect of the present invention, the present invention proposes a method for preparing a flexible all-solid-state battery.

According to an embodiment of the present invention, the method includes: coating a composite solid electrolyte on the surface of a composite positive electrode and drying it to obtain a composite sheet; and attaching a negative electrode on the surface of the composite sheet to obtain the flexible all-solid-state battery ; Wherein, the composite solid electrolyte is the composite solid electrolyte of any of the above or the composite solid electrolyte prepared by any of the above methods.

The inventors unexpectedly found that the preparation method of the flexible all-solid-state battery according to the embodiment of the present invention is simple, the process conditions are mild, no complicated equipment is required, and the preparation cycle is short, which is conducive to mass production and manufacturing, and can prepare A flexible all-solid-state battery that can be used at high temperatures, has high mechanical strength, good safety performance, excellent area specific capacity and energy density, low battery internal resistance, high flexibility, and can be bent and cut without affecting the use . Those skilled in the art can understand that the features and advantages described above for the composite solid electrolyte, its preparation method and flexible all-solid-state battery are still applicable to the preparation method of the flexible all-solid-state battery, and will not be repeated here.

In addition, the preparation method according to the above-mentioned embodiments of the present invention may also have the following additional technical features:

According to an embodiment of the present invention, the composite positive electrode is obtained through the following steps: secondly mixing the positive electrode active material, the second lithium salt, the second polymer matrix and the conductive additive in an organic medium to obtain the positive electrode slurry, The positive electrode slurry is shaped to obtain a composite positive electrode.

Therefore, using the preparation method of the embodiment of the present invention, the preparation method is simple, the process conditions are mild, no complicated equipment is needed, and the preparation cycle is short, and it can produce high ion transport properties, high electron conductivity, and composite solid electrolytes with good properties. interface contact, and has a flexible composite positive electrode.

According to an embodiment of the present invention, the forming includes: coating the positive electrode slurry on an aluminum foil and drying it to obtain a composite positive electrode; or drying the positive electrode slurry, and drying the dried product on an aluminum foil pressed in order to obtain a composite positive electrode. The inventors unexpectedly found that the performance of the composite positive electrode sheet obtained by pressing the positive electrode slurry after drying is similar to that of the composite positive electrode sheet obtained by directly coating and drying the positive electrode slurry, and the internal structure of the former is denser. Therefore, using the method of the embodiment of the present invention, the composite positive electrode prepared has higher ion transport and electronic conductivity, better interface contact with the composite solid electrolyte, and better flexibility.

According to an embodiment of the present invention, the drying is carried out at a temperature of 20-100 degrees Celsius, preferably 60 degrees Celsius; the drying time is 5-48 hours, preferably 12 hours; the surface of the composite sheet The thickness of the composite solid electrolyte is 10-200 microns, preferably 40 microns; the second mixing time is 5-48 hours, preferably 12-24 hours; the pressing pressure is 2-20 MPa, preferably Ground, 4MPa; and the thickness of the composite positive electrode is 20-1000 microns.

The inventors of the present invention have found through long-term research that in the process of preparing composite positive electrodes, composite solid-state electrolytes and flexible all-solid-state batteries, the numerical range of each process condition will affect the final performance of flexible all-solid-state batteries. If the drying time is less than 5 hours, the slurry cannot be shaped, and if the drying time exceeds 48 hours, the flexibility of the sheet will be reduced, so 12 hours of drying is the most suitable; the length of mixing time will affect the uniformity of the composite positive electrode and composite solid electrolyte , the mixing is too short, the mixing effect is not good if it is shorter than 5 hours, and the cost is wasted if it exceeds 48 hours, so the effect of mixing for 12 to 24 hours is the best; the thickness of the composite positive electrode is preferably 20 to 1000 microns, and it is not easy to prepare if it is too thin. And the energy density of the battery is low, if it is too thick, the flexibility of the all-solid-state battery will be greatly reduced; while the thickness of the composite solid-state electrolyte on the surface of the composite sheet should be 10-200 microns, if it is thinner than 10 microns, the capacity of the all-solid-state battery will be too small, The thickness of 200 microns affects the flexibility of all solid-state batteries, so the thickness of the composite solid electrolyte is 40 microns is the best.

Therefore, using the method of the embodiment of the present invention, the preparation method is simple, the process conditions are mild, and the preparation cycle is short, which is beneficial to mass production and manufacturing, and can be used at high temperature, with high mechanical strength and good safety performance. , has excellent area specific capacity and energy density, and the internal resistance of the battery is small, and the flexibility is high, and the flexible all-solid-state battery that can be bent and cut will not affect the use.

In a fifth aspect of the present invention, the present invention provides a wearable electronic device. According to an embodiment of the present invention, the wearable electronic device includes the above-mentioned flexible all-solid-state battery. Those skilled in the art can understand that the wearable electronic device may also include other necessary components, such as an integrated circuit, an output device, an input device, and a casing, which will not be repeated here.

The inventors unexpectedly found that, using the wearable electronic device according to the embodiment of the present invention, the all-solid-state battery of the device is small in size, large in capacitance and good in flexibility, and can be bent and cut without affecting the use of the battery. Those skilled in the art can understand that the features and advantages described above for the composite solid electrolyte and the flexible all-solid-state battery are still applicable to the wearable electronic device, and will not be repeated here.

Additional aspects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Description of drawings

The above and/or additional aspects and advantages of the present invention will become apparent and comprehensible from the description of the embodiments in conjunction with the following drawings, wherein:

Fig. 1 is a scanning electron micrograph of a cross-section of a composite positive electrode according to an embodiment of the present invention;

2 is an electrochemical impedance diagram of a composite solid electrolyte at room temperature according to another embodiment of the present invention;

Fig. 3 is a charge-discharge curve of an all-solid-state battery at 60 degrees Celsius according to another embodiment of the present invention; and

Fig. 4 is a working diagram of bending and cutting of an all-solid-state battery according to another embodiment of the present invention.

detailed description

The following describes the embodiments of the present invention in detail, and those skilled in the art will understand that the following embodiments are intended to explain the present invention, and should not be regarded as limiting the present invention. Unless otherwise specified, those skilled in the art can follow the commonly used techniques or conditions in the field or follow the product specification for those that do not explicitly describe specific techniques or conditions in the following examples. The reagents or instruments used were not indicated by the manufacturer, and they were all commercially available conventional products.

The present invention will be described below with reference to specific embodiments. It should be noted that these embodiments are only illustrative and do not limit the present invention in any way.

general method

Unless clearly stated, the following electrochemical test conditions and sample preparation methods are adopted in the following examples:

Instrument model: ZAHNER elektrik IM6 impedance analyzer, LAND electrochemical workstation;

The parameters of electrochemical impedance test: the amplitude range of AC voltage is 5-50mV, the frequency range of electrochemical workstation is 0.1Hz-8MHz, or the frequency range of impedance analyzer is 40Hz-110MHz;

Parameters of charge and discharge performance test: voltage range 2.3V-3.8V, test current 100 microamperes/cm ² ; and

Preparation of electrochemical impedance samples: The electrolyte slurry was vacuum-dried at 60 degrees Celsius for 12 hours, rolled to form an electrolyte film after drying, and a 200nm-thick gold layer was sputtered on the upper and lower surfaces respectively, as an ion-blocking electrode, which can pass through the fixture Add to the electrochemical workstation or impedance analyzer for testing.

Example 1

In this embodiment, the positive electrode active material is nickel-cobalt-manganese ternary material (LiNi _0.5 Co _0.2 Mn _0.3 O ₂ ), the polymer matrix is polyethylene oxide, the lithium salt is lithium trifluoromethanesulfonate ammonium, and the conductive additive For indium oxide, the 4 raw materials were mixed in acetonitrile at a mass ratio of 5:1:1:3, and stirred at room temperature for 12 hours to obtain a composite cathode slurry. The composite positive electrode slurry was vacuum-dried at 60°C for 12 hours to obtain a composite positive electrode precursor powder, and finally the composite positive electrode precursor powder was pressed under a pressure of 4 MPa to obtain a composite positive electrode sheet with a thickness of 200 microns.

The cross-sectional scanning electron micrograph of the composite positive electrode sheet of this embodiment is shown in FIG. 1 . It can be seen from Figure 1 that the composite positive electrode sheet prepared by the compression molding method is denser, and there is no obvious larger cavity between the particles, which can provide better ion and electron transport channels, and at the same time, the polymer electrolyte tightly adheres the particles. Together, the composite positive sheet is flexible.

Example 2

In this example, lithium cobaltate is used as the positive electrode active material, chlorohydrin rubber as the polymer matrix, lithium perchlorate is selected as the lithium salt, and indium oxide is used as the conductive additive. The mass ratio of the four raw materials is 2:1:1: 1 was mixed in acetone and stirred at room temperature for 12 hours to obtain a composite positive electrode slurry. The composite positive electrode slurry was directly coated on the aluminum foil, and dried under vacuum at 60° C. for 12 hours to obtain a composite positive electrode sheet with a thickness of 20 μm.

Example 3

In this example, the positive electrode active material is lithium iron phosphate, the polymer matrix is polyethylene oxide, the lithium salt is lithium hexafluorophosphate, and the conductive additive is conductive graphite. The mass ratio of the four raw materials is 36:1:1:2. After mixing with nitrile, the mixture was stirred at room temperature for 12 hours to obtain a composite positive electrode slurry. The composite positive electrode slurry was vacuum-dried at 60°C for 12 hours to obtain a composite positive electrode precursor powder, and finally the composite positive electrode precursor powder was pressed under a pressure of 6 MPa to obtain a composite positive electrode sheet with a thickness of 1000 microns

Example 4

In this embodiment, the ceramic-based solid electrolyte is lithium lanthanum titanium oxide, the polymer matrix is polyacrylonitrile, and the lithium salt is lithium perchlorate. amide, and stirred at room temperature for 24 hours to obtain a composite solid electrolyte slurry. According to the sample preparation method and test conditions basically the same as the general method, the electrochemical impedance test was performed on the electrochemical impedance sample prepared from the composite solid electrolyte slurry in Example 4.

For the electrochemical impedance data of this embodiment, the total resistance of the sample can be further obtained by performing equivalent circuit fitting through software. According to the parameters such as the thickness of the sample and the area of the gold electrode, the total conductivity of the sample can be finally calculated. Therefore, the composite solid electrolyte of this embodiment has a total ion conductivity of 2×10 ⁻⁴ S/cm at room temperature.

Example 5

In this example, the ceramic-based solid electrolyte is lithium lanthanum zirconium oxide, the polymer matrix is polyethylene oxide, and the lithium salt is lithium ammonium trifluoromethanesulfonate. The three raw materials are mixed in a mass ratio of 8:1:1 mixed in acetonitrile and stirred at room temperature for 24 hours to obtain a composite solid electrolyte slurry. According to the sample preparation method and test conditions basically the same as the general method, the electrochemical impedance test was performed on the electrochemical impedance sample prepared from the composite solid electrolyte slurry in Example 5.

The room temperature impedance diagram of the composite solid electrolyte of this embodiment is shown in FIG. 2 . It can be seen from Figure 2 that the impedance data consists of a semi-circular arc and a straight line. The straight line is caused by the blocking electrodes at both ends of the electrolyte. The total resistance obtained by fitting is 510Ω. In addition, the composite solid electrolyte of this embodiment has a total ion conductivity of 4×10 ⁻⁵ S/cm at room temperature.

Example 6

In this example, the ceramic-based solid electrolyte is made of lithium germanium aluminum phosphate, and the lithium salt is lithium hexafluorophosphate. The three raw materials are mixed in acetonitrile at a mass ratio of 4:3:3, and stirred at room temperature for 24 hours. A composite solid electrolyte slurry is obtained. According to the sample preparation method and test conditions basically the same as the general method, the electrochemical impedance test was performed on the electrochemical impedance sample prepared from the composite solid electrolyte slurry in Example 6.

The composite solid electrolyte of this embodiment has a total ion conductivity of 3×10 ⁻⁶ S/cm at room temperature.

Example 7

In this example, a composite positive electrode sheet, a composite sheet, and an all-solid-state lithium-ion battery were sequentially prepared, and then the charge-discharge performance test was performed on the all-solid-state lithium-ion battery.

(1) After mixing lithium iron phosphate positive electrode active material, polyethylene oxide, lithium ammonium trifluoromethanesulfonate, and indium oxide in acetonitrile according to a mass ratio of 7:1:1:1, stir at room temperature for 24 hours, Obtain composite positive electrode slurry; vacuum dry the composite positive electrode slurry at 60°C for 24 hours to obtain composite positive electrode precursor powder, and then press the composite positive electrode precursor powder on aluminum foil under a pressure of 4MPa to obtain a composite positive electrode with a thickness of 300 microns piece;

(2) After mixing lithium lanthanum zirconium oxide, polyethylene oxide, and lithium ammonium trifluoromethanesulfonate in acetonitrile according to a mass ratio of 6:1:1, stir at room temperature for 24 hours to obtain a composite solid electrolyte slurry; Print the composite solid electrolyte slurry on the side of the composite positive electrode sheet that is not in contact with the aluminum foil; then place the positive electrode sheet printed with the composite solid electrolyte at 60°C for 24 hours in vacuum to obtain a layer of composite solid state with a thickness of 40 microns on the surface. Composite sheet of electrolyte;

(3) The lithium sheet is directly pasted on the dried all-solid electrolyte, and packaged with a button cell to obtain an all-solid battery.

The charge-discharge curve of the all-solid-state lithium-ion battery of this embodiment is shown in FIG. 3 . It can be seen from Figure 3 that the prepared all-solid-state battery has a very high area specific capacity, a clear charge-discharge platform, a discharge capacity close to the theoretical discharge capacity of the positive electrode material, and a Coulombic efficiency of the battery close to 100%.

Moreover, the all-solid-state lithium-ion battery of this embodiment is flexible, and its bending and cutting will not affect its use, as shown in FIG. 4 .

Example 8

In this example, a composite positive electrode sheet, a composite sheet, and an all-solid-state lithium-ion battery were sequentially prepared.

(1) Mix nickel-cobalt-manganese ternary material (LiNi _0.5 Co _0.2 Mn _0.3 O ₂ ) positive electrode active material, polyethylene oxide, lithium perchlorate, and conductive graphite in acetonitrile at a mass ratio of 7:1:1:1 Finally, stir at room temperature for 24 hours to obtain a composite positive electrode slurry; print the composite positive electrode slurry on an aluminum foil, and then place it at 60°C for 24 hours in vacuum to obtain a composite positive electrode sheet with a thickness of 20 microns;

(2) Lithium lanthanum zirconium oxide, polyethylene oxide, and lithium perchlorate were mixed in acetonitrile according to a mass ratio of 8:1:1, and stirred at room temperature for 24 hours to obtain a composite solid electrolyte slurry; the composite solid electrolyte slurry Print on the side of the composite positive electrode sheet that is not in contact with the aluminum foil; then place the positive electrode sheet printed with the composite solid electrolyte slurry at 60°C for 24 hours in vacuum to obtain a composite sheet covered with a layer of composite solid electrolyte with a thickness of 40 microns ;

(3) The lithium sheet is directly pasted on the dried all-solid electrolyte, and packaged with a button cell to obtain an all-solid battery.

Summarize

From the comprehensive examples 1 to 8, it can be concluded that the flexible all-solid-state lithium ion battery and its preparation method proposed by the present invention are simple, the process conditions are mild, no complicated equipment is required, and the preparation cycle is short, which is beneficial to mass production And manufacturing, and can be used at high temperature, high mechanical strength, good safety performance, excellent area specific capacity and energy density, while the internal resistance of the battery is small, and high flexibility, can be bent and cut without affecting The flexible all-solid-state battery used.

In the description of the present invention, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structure, material or characteristic is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without conflicting with each other.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and those skilled in the art can make the above-mentioned The embodiments are subject to changes, modifications, substitutions and variations.

Claims (10)

1. a composite solid electrolyte, it is characterised in that contain:

Ceramic base solid electrolyte；With

First polymer-based solid state electrolyte；

Wherein, gross weight based on described composite solid electrolyte, the content of described ceramic base solid electrolyte is 20～90 weights Amount %；

Optionally, gross weight based on described composite solid electrolyte, the content of described ceramic base solid electrolyte is 40～80 Weight %, the content of described first polymer-based solid state electrolyte is 20～60 weight %.

Composite solid electrolyte the most according to claim 1, it is characterised in that

Described ceramic base solid electrolyte includes selected from lithium lanthanum zirconium oxygen, Li-La-Ti oxygen, titanium phosphate aluminum lithium and phosphoric acid germanium aluminum lithium extremely Few one；

Described first polymer-based solid state electrolyte includes:

First lithium salts, described lithium salts includes selected from lithium perchlorate, trifluoromethane sulfonic acid amine lithium, lithium hexafluoro phosphate, LiBF4 With at least one of diacetic acid Lithium biborate；And

First macromolecule matrix, described macromolecule matrix includes selected from polyethylene glycol oxide or its modifier, poly-methyl methacrylate Ester or its modifier, Kynoar or its modifier, polyacrylonitrile or its modifier and chlorohydrin rubber or its modifier are extremely Few one.

3. a flexible all-solid-state battery, it is characterised in that be electrolysed containing the composite solid described in any one of claim 1～2 Matter.

Flexible all-solid-state battery the most according to claim 3, it is characterised in that possibly together with anode composite and negative pole；

Gross weight based on described anode composite, described anode composite includes:

Positive active material, its content is 40～90 weight %, it is preferable that 50～75 weight %,

Second polymer-based solid state electrolyte, its content is 5～40 weight %, it is preferable that 20 weight %, and

Conductive additive, its content is 5～30 weight %；

Wherein, described positive active material, including selected from cobalt acid lithium, LiMn2O4, LiFePO4 and nickel-cobalt-manganese ternary material extremely Few one；

Described second polymer-based solid state electrolyte contains:

Second lithium salts, described lithium salts includes selected from lithium perchlorate, trifluoromethane sulfonic acid amine lithium, lithium hexafluoro phosphate, LiBF4 With at least one of diacetic acid Lithium biborate；With

Second macromolecule matrix, described macromolecule matrix includes selected from polyethylene glycol oxide or its modifier, poly-methyl methacrylate Ester or its modifier, Kynoar or its modifier, polyacrylonitrile or its modifier and chlorohydrin rubber or its modifier are extremely Few one；

Described conductive additive, including selected from tin indium oxide, Indium sesquioxide., tin ash, zinc oxide, nickel oxide, ferroso-ferric oxide, At least one of conductive carbon black, electrically conductive graphite, CNT, Graphene, carbon fiber and acetylene；And

Described negative pole, including selected from lithium sheet, graphite material, agraphitic carbon, lithium titanate, titanium oxide, silicon, germanium, stannum, antimony, stannum oxide, At least one of silicon oxide, ferrum oxide, cobalt oxide, nickel oxide, molybdenum oxide and copper oxide.

5. the method for the composite solid electrolyte prepared described in any one of claim 1～2, it is characterised in that including:

Ceramic base solid electrolyte and the first polymer-based solid state electrolyte are mixed according to predetermined ratio, in order to obtain described multiple Close solid electrolyte.

Method the most according to claim 5, it is characterised in that including:

Described ceramic base solid electrolyte, the first macromolecule matrix and the first lithium salts are carried out the first mixing in organic media；

Wherein, described organic media is the good solvent of described macromolecule matrix, including selected from acetonitrile, acetone, butanone, dimethyl methyl At least one in amide and oxolane；And

The time of described first mixing is 5～48 hours, it is preferable that 12～24 hours.

7. the method for the flexible all-solid-state battery prepared described in claim 3～4, it is characterised in that including:

Composite solid electrolyte it is coated in the surface of anode composite and is dried, in order to obtaining composite sheet；With

Negative pole is attached, in order to obtain described flexible all-solid-state battery on the surface of described composite sheet；

Wherein, described composite solid electrolyte is the composite solid electrolyte described in any one of claim 1～2 or according to power Profit requires prepared by the method described in 5～6 any one.

Method the most according to claim 7, it is characterised in that described anode composite obtains through the following steps:

Positive active material, the second lithium salts, the second macromolecule matrix and conductive additive are carried out the second mixing at organic media, So that acquisition anode sizing agent, described anode sizing agent is shaped, in order to obtain anode composite；

Wherein, described molding includes:

Described anode sizing agent it is coated on aluminium foil and is dried, in order to obtaining anode composite；Or

Described anode sizing agent is dried, dried product is suppressed on aluminium foil, in order to obtain anode composite.

9. according to the method described in claim 7 and 8, it is characterised in that

Described being dried is carried out at a temperature of 20～100 degrees Celsius, it is preferable that 60 degrees Celsius；

The described dry time is 5～48 hours, it is preferable that 12 hours；

The thickness of the composite solid electrolyte on described composite sheet surface is 10～200 microns, it is preferable that 40 microns；

The time of described second mixing is 5～48 hours, it is preferable that 12～24 hours；

The pressure of described compacting is 2～20MPa, it is preferable that 4MPa；And

The thickness of described anode composite is 20～1000 microns.

10. a wearable electronic, it is characterised in that include the flexible all-solid-state battery described in claim 3～4.