A method for preparing a negative electrode material for a fast-charging lithium-ion battery and its application in electrochemical devices

Abstract

The present application discloses a method for preparing a negative electrode material for a fast-chargeable lithium-ion battery and its application in electrochemical devices. The lithium-ion battery negative electrode material in the present application comprises a coated ferromanganese borate material, an ion-doped compound based on ferromanganese borate, and an ion-doped and coated ferromanganese borate material, the main component of which is an inorganic compound called FeMnBO4. The FeMnBO4 / C material prepared in the present application has an energy density higher than that of traditional graphite and lithium titanate negative electrode materials, an operating voltage lower than that of lithium titanate, and high-rate rapid charge and discharge characteristics. The present application discloses a new lithium-ion battery negative electrode material with promising application prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of lithium ion batteries, and in particular relates to a method for preparing a negative electrode material for a fast-chargeable lithium ion battery and its application in electrochemical devices. Background Art

[0002] In recent years, the excessive use of fossil energy such as oil and natural gas has brought serious environmental pollution and energy shortage crisis to the whole society. Therefore, there is an urgent need for a green and reliable energy storage device to replace the current fuel vehicles and reduce the use of fossil energy. Lithium-ion batteries are currently the most energy-dense commercial batteries (greater than 200Whkg). -1 ), green and environmentally friendly energy storage equipment with a long service life, is widely used in electric vehicles and electronic products. However, the development of lithium-ion battery fast charging technology is severely restricted by the negative electrode material. The development of negative electrode materials has gone through a series of new materials such as hard carbon, soft carbon, graphite and lithium titanate. The electrochemical performance indicators of these materials have their own advantages. Among them, the mainstream negative electrode materials are mainly divided into two categories: graphite and lithium titanate. Among them, graphite and lithium titanate are two types of negative electrode materials currently used in lithium-ion batteries. Graphite as a negative electrode material for lithium-ion batteries has a capacity of nearly 372mAh g -1 The specific capacity, however, is relatively low in lithium storage potential (close to 0V vs. Li / Li + ), resulting in poor rate capability and serious safety hazards, thus limiting its use in fast-charge lithium-ion batteries. Another lithium titanate (Li4Ti5O 12 ) The negative electrode material has a suitable lithium storage potential (1.55Vv.Li / Li + ), but its specific capacity is only 200mAhg -1, which severely impacts the energy density of this type of battery. In addition to carbon and lithium titanate anode materials, recent research has focused on tin-based and silicon-based materials. Research on tin-based materials has focused on tin alloying and carbon-tin composites. Composites of elemental tin and carbon are the most commonly used methods to improve the cyclability of tin anodes. Patent document (CN200910048318.6) proposes using high-temperature chemical vapor deposition and reduction to produce tin-carbon / core-shell nanoparticles. This structured anode material can achieve a reversible lithium storage capacity exceeding 700 mAh / g. Patent document (CN201110058034.2) uses a mesoporous carbon matrix as a carrier to in situ grow tin nanoparticles within the mesoporous channels. The mesopores suppress the volume change of the active particles during lithium ion insertion and extraction, thereby improving the cycling performance of lithium-ion batteries. Research on silicon anodes primarily involves ball-milling silicon powder with a carbon source material, followed by pyrolysis, to produce a silicon-carbon composite material. Since the ball milling method is difficult to effectively control the particle size, morphology, and orientation of nano-silicon particles, and it is difficult to achieve a single and uniform dispersion of nano-silicon particles in the carbon carrier, the cycle performance of the silicon-carbon composite material prepared by the ball milling method is poor. Patent document (CN200910082897.6) proposes a nano-silicon amorphous carbon composite lithium ion battery negative electrode material, the negative electrode material particles are a nano-sized core-shell structure particle, the core of the nanoparticle is nano-silicon, and the shell is amorphous carbon obtained by pyrolysis of organic matter. In recent years, researchers have greatly improved the cycle stability of silicon materials by preparing silicon nanowires (Candace K. Chan, Hailin Peng, Gao Liu, Yi Cui. Nat. Nanotechnol, 2008, 3 (1); 31-35). However, since these materials do not contain conductive carriers, silicon can directly contact the electrolyte, so the material is highly polarized under high current charge and discharge conditions, which limits its practical application. The above methods have improved the material's cycling performance to a certain extent, but long-term charging and discharging still lead to the collapse of the material structure and the pulverization and peeling of the electrode material, which results in poor contact between the material and the current collector and a sharp decline in the electrode's cycling performance. Although tin-based and silicon-based materials have large capacities, their large irreversible capacity during the first charge and discharge and poor cycling performance limit their commercialization. Treatment methods such as carbon coating are relatively complex and difficult to apply on a large scale, which in turn limits the commercialization of the material. Summary of the Invention

[0003] Technical issues solved:

[0004] This application addresses the deficiencies of the existing technology and solves the current technical problems of low capacity, poor rate performance, and volume expansion of silicon-based negative electrode materials. It provides a method for preparing a negative electrode material for fast-charging lithium-ion batteries and its application in electrochemical devices. The iron manganese borate negative electrode material is different from existing commercial lithium-ion battery negative electrodes such as graphite and lithium titanate. It is a new type of lithium-ion battery negative electrode material with low cost, high specific capacity, and fast charge and discharge. The FeMnBO4@C negative electrode material of the present invention undergoes a transformation and alloying process during the lithium storage process, providing a capacity greater than 1300mAhg -1 The material has a high specific capacity with minimal volume change, and exhibits excellent fast-charging performance and cycle stability. It is a new type of negative electrode material for lithium-ion batteries with great application prospects. It can also greatly improve the endurance of lithium-ion battery electric vehicles.

[0005] Technical solution:

[0006] To achieve the above objectives, this application is implemented through the following technical solutions:

[0007] A method for preparing a negative electrode material for a fast-chargeable lithium-ion battery comprises the following steps:

[0008] Step 1, weighing 4.04-8.08 parts of iron source and 0.4-1.24 parts of boron source in a mass ratio and dissolving them in 100-150 parts of deionized water, then preparing and adding 1.79-3.46 parts of manganese source solution, stirring continuously and heating the mixed solution at 40-60 ° C and stirring for 2 hours, then filtering the obtained precipitated product, washing it with deionized water several times, and drying it at 60 ° C for 24 hours, and grinding it to obtain a uniformly mixed precursor powder; Step 2, placing the above-obtained precursor powder in a porcelain boat, placing it in a tube furnace and pre-calcining it at 300 ° C for 3 hours, and then ball milling the product with 0.2-0.4 parts of carbon source to mix it evenly, and then heating it to 500-700 ° C at a heating rate of 5-10 ° C / min and calcining it for 12 hours. The sintering protective atmosphere is nitrogen, and by ball milling and mixing with the carbon source, a black carbon-coated iron manganese borate composite product FeMnBO4@C negative electrode material is obtained in situ after high-temperature carbonization.

[0009] Furthermore, in step 1, the iron source is ferric nitrate nonahydrate, the boron source is boric acid or sodium borate, and the manganese source is manganese acetate or manganese nitrate; in step 2, the carbon coating is a single layer or multilayer coating, the coating method is a ball milling carbonization method, and the carbon is one or more of hard carbon, carbon black, natural graphite, artificial graphite, expanded graphite, and amorphous carbon.

[0010] Furthermore, in step 2, the carbon source is glucose and / or sucrose, and the carbon content of the ball-milled mixed product is 5%-10% by mass.

[0011] Furthermore, the positions of Fe, Mn, B and O elements in the FeMnBO4@C inorganic material can be replaced by other elements, which are cations, anions or co-doping of several elements. The cation is Li + , K + Mg 2+ 、Sr + 、Al 3+ 、Ge 4+ 、Sn 2+ 、Sn 4+ Sc 3+ 、V 3+ 、V 5+ Cr 3+ 、Mn 3+ 、Mn 4+ 、Mn 7+ 、Fe 3+ 、Co 3+ 、Co 4+ 、Ni 2+ 、Ni 3+ 、Ni 4+ 、Cu 2+ 、Zn 2+ 、Zr 4+ 、W 3+ 、W 4+ 、W 6+ 、Mo 4+ 、Mo 6+ One or more of the anions, wherein the anion is S 2- 、F - 、Cl - Br - , I - 、CO3 2- 、SO4 2- 、SiO4 4- One or more of the .

[0012] Furthermore, the iron-manganese borate composite product has a microscopic morphology, and the microscopic morphology is micrometer scale, nanometer scale, nanometer-micrometer composite structure or macropore, mesopore, or micropore structure.

[0013] The present application also discloses the use of the negative electrode material for a fast-chargeable lithium-ion battery prepared by the above-mentioned preparation method in an electrochemical device. The electrochemical device has a cylindrical, square, or button-shaped shape, and its shell is made of organic plastic, metal material, or a composite material of metal-organic material; the interior of the electrochemical device is composed of a negative electrode membrane, an electrolyte containing anions and cations and having ionic conductivity, a separator, and a lithium sheet from bottom to top;

[0014] The electrolyte used in the electrochemical device is a non-aqueous electrolyte, which includes one or more of an organic liquid electrolyte, an ionic liquid electrolyte, a polymer electrolyte, and an all-solid electrolyte; the organic liquid electrolyte used in the device is composed of electrolyte cations, anions, and an organic solvent:

[0015] The negative electrode film composition is composed of FeMnBO4@C negative electrode material, an additional electronic conductive agent, a binder and a solvent, wherein the electronic conductive agent accounts for no more than 50% of the total mass of the slurry, and the binder accounts for no more than 20% of the total mass of the slurry;

[0016] The electronic conductive agent is one or more of graphite, carbon black, and acetylene black;

[0017] The binder is one or more of polytetraethylene, water-soluble rubber, and cellulose;

[0018] The solvent is selected from one or more of N-methylpyrrolidone NMP, dimethylformamide DMF, and diethylformamide DEF. The electronic conductive agent is made into a slurry, and the slurry is applied to the electrode current collector to obtain a negative electrode film. The current collector material is a porous, mesh or thin film material of a metal, and the metal is one or more of nickel, aluminum, copper, stainless steel, and titanium. The amount of the solvent used is 4-10 drops.

[0019] The electrolyte containing anions and cations and having ionic conductivity is a non-aqueous electrolyte, and the non-aqueous electrolyte includes one or more of an organic liquid electrolyte, an ionic liquid electrolyte, a polymer electrolyte, and an all-solid electrolyte;

[0020] The diaphragm is an existing commercial lithium-ion battery diaphragm or a glass fiber diaphragm, and the existing commercial lithium-ion battery diaphragm is a porous polystyrene or polyethylene diaphragm.

[0021] Furthermore, the cation in the organic liquid electrolyte is tetraethylammonium (C2H5)4N + , Tetrabutylammonium (C4H9)4N + 、Lithium ion Li + One or more of the following, the anion is hexafluorophosphate PF6 - , tetrafluoroborate BF4 - , trifluoromethanesulfonate CF3SO3 - 、Perchlorate ClO4 - The organic solvent is one or more of dimethyl carbonate DMC, diethyl carbonate DEC, ethylene carbonate EC, propylene carbonate PC, methyl vinyl carbonate EMC, methyl propyl carbonate MPC, 1,2-dimethoxyethane DME, and 1,4-butyrolactone GBL.

[0022] Furthermore, the volume proportion of the organic solvent is not less than 50%, and the lithium salt concentration is not higher than 1 molL -1 ; The ionic liquid is one or more of a piperidine ionic liquid and an imidazole ionic liquid; the lithium salt is one or more of lithium hexafluorophosphate LiPF6, lithium tetrafluoroborate LiBF4, and lithium bis(trifluoromethylsulfonyl)imide LiTFSI; the organic solvent is one or more of a carbonate, a carboxylate, an ether or a ketone; the carbonate is one or more of dimethyl carbonate, diethyl carbonate, ethylene carbonate, propylene carbonate, butylene carbonate, ethylene carbonate, methyl vinyl carbonate, and methyl propyl carbonate; the carboxylate is one or more of methyl formate, ethyl formate, methyl acetate, ethyl acetate, propyl acetate, ethyl propionate, methyl butyrate, and ethyl butyrate; the ether is one or more of dimethoxymethane, 1,2-dimethoxyethane, tetrahydrofuran, and 1,2-dioxolane; the ketone is γ-butyrolactone.

[0023] Furthermore, the polymer electrolyte is composed of a high molecular weight polymer, a lithium salt and an additive, wherein the volume proportion of the additive is not less than 50%, and the concentration of the lithium salt is not higher than 1 molL -1 ; The high molecular polymer is selected from one or more of polymethyl methacrylate PMMA, polyvinylidene fluoride PVDF, polytetrafluoroethylene PTFE, polyethylene oxide PEO, polyethylene-polypropylene-polyethylene block copolymer, polyvinyl alcohol PVA, and polyvinyl butyral PVB; the weight average molecular weight of the high molecular polymer is 50,000-500,000.

[0024] Furthermore, the all-solid electrolyte is composed of polyethylene oxide, lithium salt and ultrafine powder filler, the mass proportion of the ultrafine powder filler does not exceed 20%, and the lithium salt concentration is not higher than 1 molL -1 The ultrafine powder filler is nano-heterostilbene, nano-aluminum oxide Al2O3, nano-titanium dioxide TiO2, nano-zirconium dioxide ZrO2, nano-silicon dioxide SiO2 or nano-clay; the lithium salt is one or more of lithium hexafluorophosphate LiPF6, lithium tetrafluoroborate LiBF4, lithium bis(trifluoromethylsulfonyl)imide LiTFSI, lithium perchlorate LiClO4, lithium hexafluoroarsenate LiAsF6, lithium halide LiCl,LiI,et.al, lithium chloroaluminate LiAlO4, and lithium fluorohydroxysulfonate LiHSO3F.

[0025] The working principle of the above-mentioned method for preparing a negative electrode material for a fast-chargeable lithium-ion battery and its application in an electrochemical device is that the prepared manganese borate has a rod-like structure with holes, which has a good lithium ion accommodation capacity and allows lithium ions to be quickly intercalated and deintercalated in the porous structure of the manganese borate. In addition, the pyrolyzed carbon can be evenly coated on the surface of the manganese borate, which can obtain better electronic conductivity and realize rapid charging and discharging functions.

[0026] Beneficial effects:

[0027] The present application provides a method for preparing a negative electrode material for a fast-chargeable lithium-ion battery and its application in an electrochemical device. Compared with the prior art, the present application has the following beneficial effects:

[0028] 1. This paper proposes a new type of negative electrode material for fast-chargeable lithium-ion batteries by combining simple carbon coating technology with the two reaction mechanisms of conversion and alloying. It successfully solves the problem of volume expansion during the alloying reaction and compensates for the problem of low capacity of conversion reaction and intercalation reaction.

[0029] 2. The FeMnBO4@C negative electrode material of the present invention undergoes transformation and alloying during the lithium storage process, providing a capacity greater than 1300 mAhg -1 It has a high specific capacity and is accompanied by a small volume change, while showing excellent fast charging performance and cycle stability. It is a new type of negative electrode material for lithium-ion batteries with good application prospects, and can greatly improve the endurance of lithium-ion battery electric vehicles.

[0030] 3. Iron manganese borate negative electrode material is different from existing commercial lithium-ion battery negative electrodes such as graphite and lithium titanate. It is a new type of lithium-ion battery negative electrode material with low cost, high specific capacity and fast charge and discharge.

[0031] 4. The carbon-coated iron manganese borate (FeMnBO4@C) inorganic material of the present application exhibits excellent electrochemical properties as a negative electrode material for lithium-ion batteries, such as high capacity, fast charging, long cycle, low cost, and environmental friendliness.

[0032] 5. The negative electrode material is 100mAg -1 At the charge and discharge current, its initial reversible capacity is 1300mAhg -1 Even at a discharge rate of 1 minute, it still has 930mAhg -1 The ultra-high capacity shows that it has excellent fast charging performance. -1 ) and graphite (370mAhg -1 ) capacity, it has obvious advantages.

[0033] 6. The synergistic use of organic solvents and ionic liquids can reduce the viscosity of ionic liquids while maintaining the advantages of high antioxidant potential and good thermal stability of ionic liquids.

[0034] 7. The carbon coating effect can shorten the diffusion path during the insertion and extraction of lithium ions, and enhance the electronic conductivity of the electrode material, thereby achieving fast charging performance of the electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A performance comparison chart of the negative electrode for the iron manganese borate lithium-ion battery in this application, commercial lithium titanate, and graphite;

[0036] Figure 2 This is the X-ray diffraction result of the ferromanganese borate of this application;

[0037] Figure 3 This is the shape diagram of ferromanganese borate in this application under field emission electron microscope;

[0038] Figure 4 This is the specific capacity diagram of ferromanganese borate at a discharge rate of 10h for this application;

[0039] Figure 5 This is a graph of the specific capacity of ferromanganese borate at different discharge rates for this application. DETAILED DESCRIPTION

[0040] In order to further illustrate the present invention, the present invention is described in further detail below with reference to the embodiments.

[0041] Example 1:

[0042] A method for preparing a negative electrode material for a fast-charging lithium-ion battery, wherein a carbon-coated ferromanganese borate FeMnBO4@C inorganic material is synthesized by a solid-phase calcination method:

[0043] According to the stoichiometric molar ratio of manganese source, boron source and iron source, 8.08 g of ferric nitrate nonahydrate and 1.24 g of boric acid were added to 150 mL of aqueous solution, stirred evenly, and then 3.46 g of manganese acetate was added. After heating and stirring at 60 ° C for 2 h, a precipitate was obtained. The solid powder was obtained by filtration and washing with deionized water several times. The solid powder was dried at 60 ° C for 24 h and ground into a uniformly mixed precursor powder.

[0044] The precursor powder obtained above was placed in a porcelain boat, placed in a tube furnace and pre-calcined at 300°C for 3h, then mixed with 0.4g sucrose and ground into a ball mill for 4h (the carbon content of the final product was 5%-10% by mass). The obtained sample was placed in a tube furnace and heated to 700°C at a heating rate of 5-10°C / min in a nitrogen atmosphere and calcined for 12h to obtain in-situ carbon-coated ferromanganese borate FeMnBO4@C inorganic material powder. The X-ray diffraction results are shown in detail. Figure 1 , and its scanning electron microscope image is shown in Figure 2 .

[0045] The prepared FeMnBO4@C powder was ground into a uniform viscous slurry with carbon black as a conductive agent and a 9% polyvinylidene fluoride binder (9% polyvinylidene fluoride dissolved in N-methyl-2-pyrrolidone). The PVDF and carbon black accounted for 10% of the total weight of the mixture. The mixture was then coated onto an aluminum foil current collector to a thickness of 0.1 mm. After the solvent evaporated, the mixture was rolled under a pressure of 1 MPa and dried in a vacuum oven at 120°C for 12 hours. This was then used as the negative electrode for a lithium-ion battery. In a glove box, the positive electrode / separator / anode assembly was assembled in the order of positive electrode / separator / anode for single-electrode testing. For single-electrode testing, a sodium foil was used as the negative electrode, and the electrolyte consisted of 1M LiPF6·EC / EMC / DMC (solvent volume ratio 1:1:1) with 1-5% FEC. Commercial lithium-ion battery separators or glass fiber were used as separators. Coin-type cells (CR2016) were assembled. The battery operating range is 0.01~3V, and the charge and discharge current is 100mAg -1 The initial reversible capacity was measured to be 1300 mAh g -1 ( Figure 3 ), even at a discharge rate of 1min, it still has 930mAhg -1 Ultra-high capacity ( Figure 4 ), it can be seen that it has excellent fast charging performance.

[0046] Example 2:

[0047] A method for preparing a negative electrode material for fast-charging lithium-ion batteries and its application in electrochemical devices, synthesizing carbon-coated iron manganese borate FeMnBO4@C inorganic material by sol-gel method:

[0048] According to the stoichiometric molar ratio of manganese source, boron source and iron source, 4.04 g of ferric nitrate nonahydrate and 0.4 g of sodium borate were added to 100 mL of distilled water, and then 1.79 g of manganese nitrate was added. The mixture was heated and stirred at 60 ° C for 2 h to obtain a precipitate. The solid powder was obtained by filtration and washing with deionized water several times. The solid powder was dried at 60 ° C for 24 h and ground into a uniformly mixed precursor powder.

[0049] The precursor powder obtained above was placed in a porcelain boat, placed in a tube furnace and pre-fired at 300°C for 3 hours, then the sample was taken out and ball-milled with 0.2g glucose for 4 hours, and placed in a tube furnace in a nitrogen atmosphere and calcined at 600°C for 12 hours to obtain in-situ carbon-coated iron manganese borate FeMnBO4@C inorganic material powder.

[0050] At the same time, the lithium ion battery negative electrode material prepared above was processed and tested according to the method in Example 1, and the performance of the obtained battery was similar to that of the battery in Example 1.

[0051] The above is an exemplary description of the present invention. It should be noted that, without departing from the core of the present invention, any simple deformation, modification or other equivalent replacement that can be made by other skilled in the art without expending creative labor falls within the scope of protection of the present invention.

Claims

1. A method for preparing a negative electrode material for a fast-chargeable lithium-ion battery, characterized in that: The following steps are involved: Step 1. Weigh 4.04-8.08 parts of iron source and 0.4-1.24 parts of boron source in a mass ratio and dissolve them in 100-150 parts of deionized water, then add 1.79-3.46 parts of manganese source solution, continue stirring and heat the mixed solution at 40-60 ° C for 2 hours, then filter the obtained precipitate, wash it with deionized water several times, and dry it at 60 ° C for 24 hours, and grind it to obtain a uniformly mixed precursor powder; Step 2: The precursor powder obtained above is placed in a porcelain boat, placed in a tube furnace and pre-calcined at 300°C for 3 hours, and then the product is mixed with 0.2-0.4 parts of a carbon source by ball milling. The mixture is then heated to 500-700°C at a heating rate of 5-10°C / min and calcined for 12 hours in a nitrogen atmosphere. The black carbon-coated iron-manganese borate composite product FeMnBO4@C negative electrode material is obtained in situ by ball milling with the carbon source and high-temperature carbonization. In step 1, the iron source is ferric nitrate nonahydrate, the boron source is boric acid or sodium borate, and the manganese source is manganese acetate or manganese nitrate; in step 2, the carbon coating is a single layer or multilayer coating, the coating method is a ball milling carbonization method, and the carbon is one or more of natural graphite, artificial graphite, expanded graphite, and amorphous carbon; In step 2, the carbon source is glucose and / or sucrose, and the carbon content of the ball-milled mixed product is 5%-10% by mass.

2. The method for preparing a negative electrode material for a fast-chargeable lithium-ion battery according to claim 1, wherein: The iron-manganese borate composite product has a microscopic morphology, and the microscopic morphology is micrometer scale, nanometer scale, nanometer-micrometer composite structure or macropore, mesopore, or micropore structure.

3. Use of a negative electrode material for a fast-chargeable lithium-ion battery prepared by the preparation method of claim 1 in an electrochemical device, characterized in that: The electrochemical device is cylindrical, square, or button-shaped, and its outer shell is made of organic plastic, metal, or a metal-organic composite material. The inside of the electrochemical device is composed of a negative electrode membrane, an electrolyte containing anions and cations and having ion conductivity, a separator, and a lithium sheet from bottom to top. The electrolyte used in the electrochemical device is a non-aqueous electrolyte, which includes one or more of an organic liquid electrolyte, an ionic liquid electrolyte, a polymer electrolyte, and an all-solid electrolyte; the organic liquid electrolyte used in the device is composed of electrolyte cations, anions, and an organic solvent: The negative electrode film composition is composed of FeMnBO4@C negative electrode material, an additional electronic conductive agent, a binder and a solvent, wherein the electronic conductive agent accounts for no more than 50% of the total mass of the slurry, and the binder accounts for no more than 20% of the total mass of the slurry; The electronic conductive agent is one or more of graphite, carbon black, and acetylene black; The binder is water-soluble rubber and / or cellulose; The solvent is selected from one or more of N-methylpyrrolidone NMP, dimethylformamide DMF, and diethylformamide DEF. The electronic conductive agent is made into a slurry, and the slurry is applied to the electrode current collector to obtain a negative electrode film. The current collector material is a porous, mesh or thin film material of a metal, and the metal is one or more of nickel, aluminum, copper, stainless steel, and titanium. The amount of the solvent used is 4-10 drops. The electrolyte containing anions and cations and having ionic conductivity is a non-aqueous electrolyte, and the non-aqueous electrolyte includes one or more of an organic liquid electrolyte, an ionic liquid electrolyte, a polymer electrolyte, and an all-solid electrolyte; The diaphragm is an existing commercial lithium-ion battery diaphragm or a glass fiber diaphragm, and the existing commercial lithium-ion battery diaphragm is a porous polystyrene or polyethylene diaphragm.

4. The use according to claim 3, characterized in that: The cation in the organic liquid electrolyte is tetraethylammonium (C2H5)4N + , Tetrabutylammonium (C4H9)4N + 、Lithium ion Li + One or more of the following, the anion is hexafluorophosphate PF6 - , tetrafluoroborate BF4 - , trifluoromethanesulfonate CF3SO3 - 、Perchlorate ClO4 - The organic solvent is one or more of dimethyl carbonate DMC, diethyl carbonate DEC, ethylene carbonate EC, propylene carbonate PC, methyl vinyl carbonate EMC, methyl propyl carbonate MPC, 1,2-dimethoxyethane DME, and 1, 4-butyrolactone GBL.

5. The use according to claim 3, characterized in that: The ionic liquid electrolyte is composed of an ionic liquid, a lithium salt and an organic solvent, wherein the volume proportion of the organic solvent is not less than 50%, and the concentration of the lithium salt is not higher than 1 mol L -1 ; The ionic liquid is one or more of a piperidine ionic liquid and an imidazole ionic liquid; the lithium salt is one or more of lithium hexafluorophosphate LiPF6, lithium tetrafluoroborate LiBF4, and lithium bis(trifluoromethylsulfonyl)imide LiTFSI; the organic solvent is one or more of a carbonate, a carboxylate, an ether or a ketone; the carbonate is one or more of dimethyl carbonate, diethyl carbonate, ethylene carbonate, propylene carbonate, butylene carbonate, ethylene carbonate, methyl vinyl carbonate, and methyl propyl carbonate; the carboxylate is one or more of methyl formate, ethyl formate, methyl acetate, ethyl acetate, propyl acetate, ethyl propionate, methyl butyrate, and ethyl butyrate; the ether is dimethoxymethane, 1,2-dimethoxyethane, or tetrahydrofuran; the ketone is γ-butyrolactone.

6. The use according to claim 3, characterized in that: The polymer electrolyte is composed of a high molecular weight polymer, a lithium salt and an additive, wherein the volume proportion of the additive is not less than 50%, and the concentration of the lithium salt is not higher than 1 mol L -1 ; The high molecular polymer is selected from one or more of polymethyl methacrylate PMMA, polyvinylidene fluoride PVDF, polytetrafluoroethylene PTFE, polyethylene oxide PEO, polyethylene-polypropylene-polyethylene block copolymer, polyvinyl alcohol PVA, and polyvinyl butyral PVB; the weight average molecular weight of the high molecular polymer is 50,000-500,000.

7. The use according to claim 3, characterized in that: The all-solid-state electrolyte is composed of polyethylene oxide, lithium salt and ultrafine powder filler, wherein the mass proportion of the ultrafine powder filler does not exceed 20%, and the lithium salt concentration is not higher than 1 mol L -1 The ultrafine powder filler is nano-heterostilbene, nano-aluminum oxide Al2O3, nano-titanium dioxide TiO2, nano-zirconium dioxide ZrO2, nano-silicon dioxide SiO2 or nano-clay; the lithium salt is one or more of lithium hexafluorophosphate LiPF6, lithium tetrafluoroborate LiBF4, lithium bis(trifluoromethylsulfonyl)imide LiTFSI, lithium perchlorate LiClO4, lithium hexafluoroarsenate LiAsF6, the lithium halide is one or more of LiCl or LiI, lithium chloroaluminate LiAlO4, and lithium fluorohydroxysulfonate LiHSO3F.

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