Solid-state electrolyte membrane, dry-method electrode, preparation method of solid-state electrolyte membrane and dry-method electrode, and deep eutectic assistance-based lithium battery

Abstract

The invention discloses a solid electrolyte membrane, a dry-method electrode, a preparation method of the dry-method electrode and a lithium battery based on deep eutectic assistance, and relates to the technical field of batteries. The solid electrolyte membrane comprises a solid electrolyte, a metal salt, a hydrogen bond donor and a binder, the electrode comprises an active substance, a conductive agent, a binder, a metal salt and a hydrogen bond donor, the solid electrolyte membrane and the electrode both contain metal salt and hydrogen bond donors, and the metal salt and the hydrogen bond donors form an electrolyte with a eutectic structure through coordination interaction between molecules. The invention also provides a lithium battery comprising the solid electrolyte membrane and / or the electrode. According to the invention, a deep eutectic electrolyte can be formed based on a metal salt and a hydrogen bond donor, the metal salt and the hydrogen bond donor are added into an active substance / solid electrolyte, and then a solid electrode piece or a solid electrolyte membrane is prepared by adopting a binder fibrillation dry method technology. The problem that a thick electrode or a solid electrolyte membrane is difficult to infiltrate by an electrolyte with relatively high viscosity can be solved.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a solid electrolyte membrane, a dry electrode and a preparation method thereof, and a deep eutectic-assisted lithium battery. Background Art

[0002] The rapid development of electric vehicles and portable electronic devices in recent years has greatly promoted the research on energy storage systems with high energy density and long cycle life. Lithium-ion batteries, as low-cost, high-energy-density energy storage systems, have been widely used in recent years. However, lithium-ion batteries with graphite as the anode have approached their theoretical energy density (300 Wh kg⁻¹), significantly limiting their further development. Lithium metal, as an electrode material with a high theoretical specific capacity (3860 mAh g⁻¹) and a low redox potential (-3.04 V vs. standard hydrogen electrode), has garnered widespread attention in recent years. However, lithium metal is chemically active, and the electroplating / stripping process in liquid electrolytes often leads to continuous fracture and remodeling of the surface solid electrolyte interface (SEI), resulting in continuous side reactions. The use of ultrathin solid electrolytes with high mechanical modulus, high ionic conductivity, and a wide voltage window to construct solid-state lithium metal batteries can significantly improve energy density. Furthermore, high-areal loading of high-voltage metal oxide cathodes is crucial for achieving high specific energy lithium metal batteries. However, the currently widely used electrode wet coating process has many limitations in the preparation of ultra-high areal loading electrodes. In addition, a large amount of expensive and toxic organic solvent N-methylpyrrolidone (NMP) is required during the electrode preparation process, and a large amount of energy is consumed during the drying process, resulting in high costs and environmental pollution.

[0003] The binder fibrillation dry process is a low-cost, efficient, clean, and scalable membrane preparation technology suitable for the preparation of thick electrodes and solid-state electrolyte membranes for solid-state lithium metal batteries. The dry process eliminates the use of organic solvents, saving costs for solvents, solvent evaporation / recovery, and drying. Furthermore, when using the binder fibrillation dry process to prepare electrodes and solid-state electrolytes, the different components can be evenly distributed, eliminating the problem of stratification between components caused by solvent evaporation. Furthermore, the solid particles of each component can be in direct contact, which is more conducive to the formation of a continuous ionic / electronic conductive network. Furthermore, the binder fibrillation dry process offers unique advantages in the preparation of thick electrodes, allowing for easy control of electrode thickness, ensuring uniformity and toughness, and avoiding electrode cracking. Furthermore, the binder fibrillation dry process does not require the use of solvents, preventing side reactions between moisture-sensitive solid electrolytes and polar solvents, thus facilitating the preparation of ultrathin solid-state electrolyte membranes while maintaining their excellent mechanical properties and high ionic conductivity.

[0004] However, in current all-solid-state batteries, the interface between the solid electrolyte and the electrode is in solid-solid contact, and PTFE has poor lithium ion conductivity. Therefore, a large external stacking pressure is required to achieve rapid ion transmission at the interface, which seriously hinders the binder fibrillation dry process technology. In terms of electrodes, due to the large thickness and high compaction density of the electrode sheet, the overall ion conductivity efficiency in the electrode sheet is low, making it difficult for solid-state batteries based on the binder fibrillation dry process technology to operate at low external stacking pressure and high load (≥20mg / cm 2 ) to achieve long-term stable charging and discharging. Summary of the Invention

[0005] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art, and to provide a solid electrolyte membrane, a dry electrode, a preparation method, and a lithium battery. Specifically, it provides a solid electrolyte membrane, a dry electrode, a preparation method, and a lithium battery based on a deep eutectic electrolyte. In order to solve the problems of unstable contact between the solid electrolyte and the electrode, slow ion migration in the thick electrode, and difficulty in electrolyte infiltration, and to solve the problem of uniform penetration of the organic electrolyte into the pores of the thick electrode, the present invention provides an in-situ deep eutectic electrolyte strategy to solve the problems of electrode infiltration and electrode / electrolyte interface in the preparation of quasi-solid-state lithium metal batteries based on the binder fibrillation dry process technology.

[0006] Deep eutectic electrolytes (DEEs) are a new type of green electrolyte system developed based on ionic liquids. They are formed by intermolecular coordination interactions between metal salts and hydrogen bond donors, resulting in a low melting point, a wide electrochemical window, and excellent thermal and chemical stability. This invention utilizes the unique solid-liquid phase transition characteristics of specific deep eutectic electrolytes during their preparation, adapted to the fibrillation dry process, to effectively address the issues of unstable contact between the electrolyte and the electrode, slow ion migration in thick electrodes, and difficulty in wetting the electrodes and electrolyte with high-viscosity electrolytes.

[0007] Specifically, the present invention combines deep eutectic electrolyte with binder fibrillation dry process technology to prepare dry electrodes and solid electrolyte membranes. The present invention solves the problem that electrolytes with high viscosity are difficult to infiltrate thick electrodes or solid electrolyte membranes by adding metal salts and hydrogen bond donors that can form deep eutectic electrolytes to active materials / solid electrolytes, and then adopts binder fibrillation dry process technology to prepare solid electrode plates or solid electrolyte membranes. The electrode plates or solid electrolyte membranes prepared by the present invention contain deep eutectic electrolytes.

[0008] The technical solutions of the present invention are as follows:

[0009] A first aspect of the present invention provides a solid electrolyte membrane, comprising the following components: a solid electrolyte, a metal salt, a hydrogen bond donor, and a binder, wherein the metal salt and the hydrogen bond donor form an electrolyte having a eutectic structure through intermolecular coordination interactions;

[0010] The metal salt includes a lithium salt;

[0011] The hydrogen bond donor is at least one of hydroxyl compounds, carboxylic acid compounds, nitrile compounds, imidazole compounds, pyridine compounds, amide compounds, sulfone compounds, pyrrole compounds, amino acid compounds and ammonium salts.

[0012] The components in the solid electrolyte membrane are calculated by mass fraction as follows: solid electrolyte 60% to 90%, metal salt 1% to 10%, hydrogen bond donor 1% to 15%, and binder 1% to 20%.

[0013] Preferably, among the hydrogen bond donors, the hydroxyl compounds are ethylene glycol, 1,2-propylene glycol, 2-cyanoethanol, and phenol; the carboxylic acid compounds are formic acid, acetic acid, glutamic acid, glycolic acid, malonic acid, oxalic acid, and levulinic acid; the nitrile compounds are succinonitrile, acetonitrile, propionitrile, dimethylmalononitrile, tricyanomethane, tetracyanoethylene, and cyanoacetic acid; the imidazole compounds are imidazole, 2-methylimidazole, 1,2-dimethylimidazole, 4(5)-hydroxyimidazole, imidazole hydrochloride, imidazole-4-carboxylic acid, N-methylimidazole, 2-aminoimidazole, and 2-imidazolidinone; and pyridine The sulfone compound is 2-cyanopyridine; the amide compound is N-methylacetamide, N-methyltrifluoroacetamide, N-ethylacetamide, N-methylpropionamide, N-benzylacetamide, acetamide, formamide, oxalamide, caprolactam, urea, N,N-dimethylpropyleneurea, tetramethylurea, trifluoroacetamide, 1,3-dimethylurea; the sulfone compound is butadiene sulfone; the pyrrole compound is 2-pyrrolidine and tetrahydropyran; the amino acid compound is N-acetylglycine; the ammonium salt is propenyl-1,3-sultone and (2-hydroxyethyl)-trimethylammonium chloride;

[0014] Preferably, the lithium salt is at least one of lithium nitrate, lithium bis(fluorosulfonyl imide), lithium bis(trifluoromethanesulfonyl imide), lithium hexafluorophosphate, lithium difluorooxalatoborate, lithium perchlorate, lithium hexafluoroarsenate, lithium difluorophosphate, lithium trifluoromethanesulfonate, lithium bis(oxalatoborate) and lithium tetrafluoroborate;

[0015] Preferably, the solid electrolyte is at least one of a sodium ultrafast ion conductor, a garnet-type solid electrolyte, an inorganic perovskite-type, and a LiPON film;

[0016] Preferably, the binder is at least one of sodium carboxymethyl cellulose, styrene-butadiene rubber, sodium carboxymethyl cellulose, polytetrafluoroethylene, polyvinylidene fluoride, and polyethylene oxide.

[0017] A second aspect of the present invention provides a method for preparing a solid electrolyte membrane, comprising the following steps:

[0018] uniformly mixing the solid electrolyte, the metal salt and the binder to obtain a first mixture;

[0019] uniformly mixing the remaining solid electrolyte, the hydrogen bond donor, and the remaining binder to obtain a second mixture;

[0020] The first mixture and the second mixture are mixed uniformly, ground, and rolled to obtain a solid electrolyte membrane.

[0021] A third aspect of the present invention provides a dry electrode, comprising the following components: an active material, a conductive agent, a binder, a metal salt, and a hydrogen bond donor, wherein the metal salt and the hydrogen bond donor form an electrolyte having a eutectic structure through intermolecular coordination interactions;

[0022] The active material is a positive electrode active material or a negative electrode active material;

[0023] The metal salt includes a lithium salt;

[0024] The hydrogen bond donor is at least one of hydroxyl compounds, carboxylic acid compounds, nitrile compounds, imidazole compounds, pyridine compounds, amide compounds, sulfone compounds, pyrrole compounds, amino acid compounds and ammonium salts.

[0025] Preferably, the components in the electrode are calculated in proportion by mass as follows: active material 50% to 90%, conductive agent 2% to 12%, binder 1% to 15%, lithium salt 1% to 15%, and hydrogen bond donor 1% to 15%.

[0026] Preferably, among the hydrogen bond donors, the hydroxyl compounds are ethylene glycol, 1,2-propylene glycol, 2-cyanoethanol, and phenol; the carboxylic acid compounds are formic acid, acetic acid, glutamic acid, glycolic acid, malonic acid, oxalic acid, and levulinic acid; the nitrile compounds are succinonitrile, acetonitrile, propionitrile, dimethylmalononitrile, tricyanomethane, tetracyanoethylene, and cyanoacetic acid; the imidazole compounds are imidazole, 2-methylimidazole, 1,2-dimethylimidazole, 4(5)-hydroxyimidazole, imidazole hydrochloride, imidazole-4-carboxylic acid, N-methylimidazole, 2-aminoimidazole, and 2-imidazolidinone; and pyridine The sulfone compound is 2-cyanopyridine and tetrahydropyran; the amide compound is N-methylacetamide, N-methyltrifluoroacetamide, N-ethylacetamide, N-methylpropionamide, N-benzylacetamide, acetamide, formamide, oxalamide, caprolactam, urea, N,N-dimethylpropyleneurea, tetramethylurea, trifluoroacetamide, 1,3-dimethylurea; the sulfone compound is butadiene sulfone; the pyrrole compound is 2-pyrrolidine; the amino acid compound is N-acetylglycine; the ammonium salt is (propenyl-1,3-sultone) and (2-hydroxyethyl)-trimethylammonium chloride;

[0027] Preferably, the lithium salt is at least one of lithium nitrate, lithium bis(fluorosulfonyl imide), lithium bis(trifluoromethanesulfonyl imide), lithium hexafluorophosphate, lithium difluorooxalatoborate, lithium perchlorate, lithium hexafluoroarsenate, lithium difluorophosphate, lithium trifluoromethanesulfonate, lithium bis(oxalatoborate) and lithium tetrafluoroborate.

[0028] Preferably, the positive electrode active material is at least one of sulfur, polyacrylonitrile, lithium iron phosphate, lithium cobalt oxide, nickel-cobalt-manganese / nickel-cobalt-aluminum ternary positive electrode and lithium-rich manganese-based positive electrode material;

[0029] Preferably, the negative electrode active material is at least one of metallic lithium, silicon-carbon negative electrode material, lithium titanate, graphite, and pure silicon;

[0030] Preferably, the conductive agent is at least one of superconducting carbon black, graphite powder, carbon nanotubes, and vapor-grown carbon fibers;

[0031] Preferably, the binder is at least one of sodium carboxymethyl cellulose, styrene-butadiene rubber, sodium carboxymethyl cellulose, polytetrafluoroethylene, polyvinylidene fluoride, and polyethylene oxide.

[0032] A fourth aspect of the present invention provides a method for preparing the electrode, comprising the following steps:

[0033] mixing the active material and the conductive carbon black to obtain a third mixture;

[0034] The third mixture is divided into two parts, a metal salt and a binder are added to one part of the third mixture, and the mixture is mixed to obtain a fourth mixture; a hydrogen bond donor and the remaining binder are added to the other part of the third mixture, and the mixture is mixed to obtain a fifth mixture;

[0035] The fourth mixture and the fifth mixture are mixed uniformly, ground, and pressed to obtain an electrode.

[0036] A fifth aspect of the present invention provides a lithium battery comprising the solid electrolyte membrane and / or the electrode.

[0037] The present invention has at least one of the following beneficial effects:

[0038] The present invention is based on the fact that metal salts and hydrogen bond donors can form a deep eutectic electrolyte. By adding metal salts and hydrogen bond donors to active materials / solid electrolytes and then using a binder fibrillation dry process to prepare solid electrode plates or solid electrolyte membranes, the problem that electrolytes with high viscosity are difficult to infiltrate thick electrodes or solid electrolyte membranes can be solved.

[0039] The present invention forms a thin interfacial liquid layer at the electrode-solid electrolyte interface by bringing the metal salt and the hydrogen bond donor into contact with each other, thereby improving the ion transport problem at each interface and enhancing the interface stability of the solid-state battery, while ensuring that the organic electrolyte uniformly penetrates into the pores of the thick electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is an optical image of a mixture of NCM811, Surper-P, PTFE, LiTFSI, and Bds in Example 1 of the present invention;

[0041] Figure 2 This is a SEM image of the electrode fiberization test in Example 1 of the present invention;

[0042] Figure 3 This is an optical photograph of the electrode flexibility test in Example 1 of the present invention;

[0043] Figure 4 is an optical image of a solution formed by LiTFSI and Bds in Example 2 of the present invention;

[0044] Figure 5 is the ionic conductivity of the electrolyte at different ratios in Example 2 of the present invention;

[0045] Figure 6 3 is a comparison of the charge and discharge curves of the lithium / (NCM811+Super-P+PTFE) and lithium / (NCM811+Super-P+PTFE+LiTFSI+Bds) half-cells assembled with electrodes in Example 3 of the present invention;

[0046] Figure 7 is an optical image of a solid electrolyte membrane synthesized from LLZTO, PTFE, LiTFSI, and Bds in Example 4 of the present invention;

[0047] Figure 8 1 is a charge and discharge curve diagram of a lithium / NCM811 quasi-solid-state battery assembled with a solid electrolyte membrane in Example 5 of the present invention;

[0048] Figure 9 This is a charge and discharge test chart of a lithium half-cell assembled with the electrode obtained in Example 11 of the present invention;

[0049] Figure 10 This is a charge and discharge test chart of a lithium half-cell assembled with the electrode obtained in Example 12 of the present invention;

[0050] Figure 11 This is a charge and discharge test chart of a lithium half-cell assembled with the electrode obtained in Example 13 of the present invention;

[0051] Figure 12 This is a charge and discharge test chart of a lithium half-cell assembled with the electrode obtained in Example 14 of the present invention;

[0052] Figure 13 This is a charge and discharge test chart of a lithium half-cell assembled with the electrode obtained in Example 15 of the present invention;

[0053] Figure 14 This is a charge and discharge test chart of a lithium half-cell assembled with the electrode obtained in Example 16 of the present invention;

[0054] Figure 15 This is a charge and discharge test chart of a lithium half-cell assembled with the electrode obtained in Example 17 of the present invention;

[0055] Figure 16 This is a charge and discharge test chart of a lithium half-cell assembled with the electrode obtained in Example 18 of the present invention. DETAILED DESCRIPTION

[0056] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0057] One embodiment of the present invention provides a solid electrolyte membrane based on a deep eutectic electrolyte, which includes the following components: a solid electrolyte, a metal salt, a hydrogen bond donor and a binder, wherein the metal salt and the hydrogen bond donor form an electrolyte with a eutectic structure through intermolecular coordination interactions; the metal salt includes a lithium salt; and the hydrogen bond donor is at least one of a hydroxyl compound, a carboxylic acid compound, a nitrile compound, an imidazole compound, a pyridine compound, an amide compound, a sulfone compound, a pyrrole compound, an amino acid compound and an ammonium salt.

[0058] The present invention utilizes metal salts and hydrogen bond donors to form a deep eutectic electrolyte. By adding the deep eutectic electrolyte to a solid electrolyte, and then adopting a binder fibrillation dry process to prepare a solid electrolyte membrane, the prepared solid electrolyte membrane contains the deep eutectic electrolyte, thereby solving the problem that electrolytes with high viscosity are difficult to infiltrate the solid electrolyte membrane and the electrode / electrolyte interface.

[0059] In some embodiments, the components of the solid electrolyte membrane are as follows by mass: solid electrolyte 60% to 90%, metal salt 1% to 10%, hydrogen bond donor 1% to 15%, and binder 1% to 20%. Preferably, the solid electrolyte is 65% to 85%, the metal salt is 2% to 9%, the hydrogen bond donor is 3% to 13%, and the binder is 5% to 18%. More preferably, the solid electrolyte is 70% to 80%, the metal salt is 3% to 8%, the hydrogen bond donor is 4% to 12%, and the binder is 8% to 15%.

[0060] In some embodiments, the solid electrolyte is an oxide solid electrolyte ceramic. Specifically, the oxide solid electrolyte ceramic is (1) a sodium ultrafast ion conductor (NASICON), such as Li3Zr2Si2PO 12 、Li 1+x Al x Ti 2-x (PO4)3(LATP, x is 0.3), Li 1.5 Al 0.5 Ge 1.5 (PO4)3(LAGP), etc.; (2) Garnet (LLZO) type, such as: Li7La3Zr2O 12 (LLZO), Li 6.5 La3Zr 1.5 Ta 0.5 O 12 (LLZTO), etc.; (3) Inorganic perovskite (LLTO) type, such as Li 0.33 La 0.56 TiO3 (LLTO), etc.; (4) LiPON thin films, such as: Li 3x (PO4) y N z (such as Li + 3.3 PO 3.9 N 0.17 ) etc.

[0061] In some embodiments, the lithium salt may include a mixture of one or more of lithium nitrate (LiNO3), lithium bis(fluorosulfonyl imide) (LiFSI), lithium bis(trifluoromethanesulfonyl imide) (LiTFSI), lithium hexafluorophosphate (LiPF6), lithium difluorooxalatoborate (LiDFOB), lithium perchlorate (LiClO4), lithium hexafluoroarsenate (LiAsF6), lithium difluorophosphate (LiPO2F2), lithium trifluoromethanesulfonate (LiOTf), lithium bis(oxalatoborate) (LiBOB), and lithium tetrafluoroborate (LiBF4).

[0062] In some embodiments, the hydrogen bond donor is (1) hydroxyl group: ethylene glycol, 1,2-propylene glycol, 2-cyanoethanol, phenol, etc.; (2) carboxylic acid: formic acid, acetic acid, glutamic acid, glycolic acid, malonic acid, oxalic acid, levulinic acid, etc.; (3) nitrile: succinonitrile, acetonitrile, propionitrile, dimethylmalononitrile, tricyanomethane, tetracyanoethylene, cyanoacetic acid, etc.; (4) imidazole: imidazole, 2-methylimidazole, 1,2-dimethylimidazole, 4 (5) -hydroxyimidazole, imidazole hydrochloride, imidazole-4-carboxylic acid, N-methylimidazole, 2-aminoimidazole, 2-imidazolidinone, etc.; (5) pyridine: tetramethyl imidazole, ... (6) Amides: N-methylacetamide, N-methyltrifluoroacetamide, N-ethylacetamide, N-methylpropionamide, N-benzylacetamide, acetamide, formamide, oxalamide, caprolactam, urea, N,N-dimethylpropyleneurea, tetramethylurea, trifluoroacetamide, 1,3-dimethylurea, etc.; (7) Sulfones: butadiene sulfone, etc.; (8) Pyrroles: 2-pyrrolidine, etc.; (9) Amino acids: N-acetylglycine, etc.; (10) Ammonium salts: one or more of propenyl-1,3-sultone, (2-hydroxyethyl)-trimethylammonium chloride, etc.

[0063] In some embodiments, the binder is one or more of CMC (sodium carboxymethyl cellulose), SBR (styrene-butadiene rubber), CMC (sodium carboxymethyl cellulose), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and polyethylene oxide (PEO).

[0064] Another embodiment of the present invention provides a method for preparing a solid electrolyte membrane, comprising the following steps:

[0065] uniformly mixing the solid electrolyte, the metal salt and the binder to obtain a first mixture;

[0066] uniformly mixing the remaining solid electrolyte, the hydrogen bond donor, and the remaining binder to obtain a second mixture;

[0067] The first mixture and the second mixture are mixed uniformly, ground, and rolled to obtain a solid electrolyte membrane.

[0068] The present invention adopts a binder fibrillation dry method to prepare a solid electrolyte membrane, which does not require the addition of a solvent, avoids the use of an organic solvent, and saves the cost of solvent, solvent evaporation / recovery and drying.

[0069] In some embodiments, the method specifically includes the following steps:

[0070] The solid electrolyte, metal salt and binder are mixed in a high-speed disperser, and the mixture is uniformly mixed under strong mechanical stirring at a stirring speed of 100 rpm to 5000 rpm for 1 minute to 120 minutes to obtain a first mixture;

[0071] The remaining solid electrolyte, hydrogen bond donor and remaining binder are mixed in a high-speed disperser, and the mixture is mixed uniformly under strong mechanical stirring at a stirring speed of 100 rpm to 5000 rpm for 1 hour to 48 hours to obtain a second mixture;

[0072] The first mixture and the second mixture are mixed in a high-speed disperser, and the mixture is mixed uniformly under strong mechanical stirring at a stirring speed of 100 rpm to 5000 rpm for 1 hour to 48 hours;

[0073] The obtained mixture is placed in a mortar and evenly ground into a flexible film. The obtained film is placed in a roller press and rolled into a certain thickness to obtain a solid electrolyte membrane.

[0074] Another embodiment of the present invention provides a dry electrode based on a deep eutectic electrolyte, which includes the following components: an active material, a conductive agent, a binder, a metal salt and a hydrogen bond donor, wherein the metal salt and the hydrogen bond donor form an electrolyte with a eutectic structure through intermolecular coordination interactions; the active material is a positive electrode active material or a negative electrode active material; the metal salt includes a lithium salt; and the hydrogen bond donor is at least one of a hydroxyl compound, a carboxylic acid compound, a nitrile compound, an imidazole compound, a pyridine compound, an amide compound, a sulfone compound, a pyrrole compound, an amino acid compound and an ammonium salt.

[0075] The present invention utilizes metal salts and hydrogen bond donors to form a deep eutectic electrolyte. By adding the deep eutectic electrolyte to the active material and the conductive agent, and then adopting the binder fibrillation dry method to prepare the electrode, the prepared electrode contains the deep eutectic electrolyte, thereby solving the problem that the electrolyte with high viscosity is difficult to infiltrate the electrode and the electrode / electrolyte interface.

[0076] In some embodiments, the components of the electrode are as follows by mass: active material 50%-90%, conductive agent 2%-12%, binder 1%-15%, lithium salt 1%-15%, hydrogen bond donor 1%-15%. Preferably, the active material is 50%-80%, conductive agent 4%-12%, binder 5%-15%, lithium salt 3%-15%, and hydrogen bond donor 3%-15%. More preferably, the active material is 55%-70%, conductive agent 6%-12%, binder 8%-15%, lithium salt 8%-15%, and hydrogen bond donor 8%-15%.

[0077] In some embodiments, the binder, metal salt, and hydrogen bond donor used in the dry electrode are the same as those used in the solid electrolyte membrane.

[0078] In some embodiments, the positive electrode active material is one or more of sulfur, polyacrylonitrile, lithium iron phosphate, lithium cobalt oxide, nickel-cobalt-manganese / nickel-cobalt-aluminum ternary positive electrode and lithium-rich manganese-based positive electrode material.

[0079] In some embodiments, the negative electrode active material is one or more of metallic lithium, silicon-carbon negative electrode material, lithium titanate, graphite, and pure silicon.

[0080] In some embodiments, the conductive agent is one or more of small-particle superconductive carbon black (Super-P), large-particle graphite powder (KS-6), carbon nanotubes (CNT), and vapor-grown carbon fiber (VGCF).

[0081] Yet another embodiment of the present invention provides a method for preparing a dry electrode based on a deep eutectic electrolyte, comprising the following steps:

[0082] mixing the active material and the conductive carbon black to obtain a third mixture;

[0083] The third mixture is divided into two parts, a metal salt and a binder are added to one part of the third mixture, and the mixture is mixed to obtain a fourth mixture; a hydrogen bond donor and the remaining binder are added to the other part of the third mixture, and the mixture is mixed to obtain a fifth mixture;

[0084] The fourth mixture and the fifth mixture are mixed uniformly, ground, and pressed to obtain an electrode.

[0085] The present invention adopts a binder fibrillation dry method to prepare the electrode, which does not require the addition of a solvent, avoids the use of an organic solvent, and saves the cost of the solvent, solvent evaporation / recovery and drying.

[0086] In some embodiments, the method specifically includes the following steps:

[0087] The active material and the conductive carbon black are mixed in a high-speed disperser, and stirred at a speed of 100 rpm to 5000 rpm for 1 to 120 minutes to obtain a uniform third mixture;

[0088] The third mixture is divided into two parts, a metal salt and a binder are added to one of the third mixtures, and the mixtures are mixed uniformly to obtain a fourth mixture; a hydrogen bond donor and the remaining binder are added to the other third mixture, and the mixtures are mixed uniformly to obtain a fifth mixture; the mixing uniformly comprises: placing the mixtures in a high-speed disperser, mixing them uniformly, and stirring at a speed of 100 rpm to 5000 rpm for 1 to 48 hours to obtain a mixture;

[0089] The fourth mixture and the fifth mixture are placed in a high-speed disperser and mixed, and stirred at a speed of 100 rpm to 5000 rpm for 1 h to 48 h;

[0090] The obtained mixture is placed in a mortar and evenly ground into a flexible film; the obtained film is placed in a roller press and rolled into a certain thickness; at a certain temperature, the film is adhered to the current collector to obtain a pole piece.

[0091] Yet another embodiment of the present invention is a lithium secondary battery capable of achieving rapid interfacial ion transport and uniform wetting of electrodes and solid electrolytes, namely, a deep eutectic-assisted lithium battery, comprising the above-mentioned solid electrolyte membrane and / or the above-mentioned electrodes.

[0092] This invention utilizes an electrolyte with a low melting point, a wide electrochemical window, and excellent thermal and chemical stability, formed through intermolecular coordination interactions between metal salts and hydrogen bond donors. By leveraging the unique solid-liquid phase transition characteristics of a specific deep eutectic electrolyte during preparation and adapting it to a fibrillation dry process, it effectively addresses issues such as unstable contact between the electrolyte and the electrode, slow ion migration in thick electrodes, and difficulty in wetting the electrode and electrolyte with high-viscosity electrolytes. This improves ion transport at each interface and enhances the interfacial stability of solid-state batteries.

[0093] In some embodiments, the battery further includes a separator, which is one or more of a polyethylene porous membrane, a polypropylene porous membrane, a polyethylene / polypropylene three-layer composite membrane, and glass fiber.

[0094] The present invention is further described in detail below with reference to specific examples, but the present invention is not limited to the following specific examples.

[0095] Example 1:

[0096] This embodiment provides a method for preparing a dry electrode, comprising the following steps:

[0097] Step 1: NCM811 (40 g) and conductive carbon black (8 g) were mixed in a high-speed disperser, and the mixture was uniformly mixed under strong mechanical stirring at a stirring speed of 2000 r / min for 35 min to obtain a mixture.

[0098] Step 2: Divide the mixture obtained in step 1 into two equal parts (24 g each), add lithium bis(trifluoromethanesulfonyl)imide (10 g) and polytetrafluoroethylene (5 g) into one part, and add butadiene sulfone (10 g) and polytetrafluoroethylene (5 g) into the other part, and mix them evenly at a speed of 3000 r / min for 2 h.

[0099] Step 3: Put the two mixtures obtained in step 2 into a high-speed disperser at a speed of 3000 r / min for 2 hours to obtain an electrode capable of achieving rapid ion transport at the interface.

[0100] Step 4: Place the mixture obtained in step 3 into a mortar and grind it evenly for 20 minutes to form a flexible film. Then place the obtained film into a roller press and roll it into a certain thickness. At a temperature of 100°C, adhere the film to the current collector to obtain a pole piece.

[0101] Figure 1 This is an optical image of the mixture obtained by mixing NCM811, Surper-P, PTFE, LiTFSI and Bds in step 2 of Example 1.

[0102] The electrode obtained in step 3 of Example 1 was tested by scanning electron microscope, and the obtained SEM image was as follows: Figure 2 As shown, it can be seen that the obtained electrode PTFE is uniformly fiberized.

[0103] The flexibility test of the electrode material obtained in step 4 of Example 1 was carried out, and the obtained optical photographs are as follows: Figure 3 As shown, the flexible characteristics of the electrode are demonstrated.

[0104] Example 2:

[0105] In order to determine the optimal mixing ratio of the lithium salt and the hydrogen bond donor to achieve an optimal ratio of the lithium salt and the hydrogen bond donor in the electrode or solid electrolyte membrane, the scheme of this embodiment is as follows:

[0106] Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and butadiene sulfone (Bds) were mixed into uniform solutions at molar ratios of 1:3, 1:4, and 1:5, respectively.

[0107] Figure 4These are optical images of a solution formed by LiTFSI and Bds in a molar ratio of 1:5 in Example 2. The left image is a image of LiTFSI and Bds immediately after addition, before a deep eutectic electrolyte is formed, and the right image is a image of a clear deep eutectic electrolyte.

[0108] The ionic conductivity of the obtained uniform solution with different proportions was tested, and the obtained ionic conductivity was as follows: Figure 5 shown.

[0109] according to Figure 5 It can be seen that the ionic conductivities of the solutions of lithium salt and hydrogen bond donor at a molar ratio of 1:3, 1:4, and 1:5 at room temperature are 0.96×10 -3 S cm -1 ; 1.2×10 -3 S cm -1 ; 1.3×10 -3 S cm -1 5 shows that the optimal molar ratio of lithium salt and hydrogen bond donor is 1:5.

[0110] Comparative Example 1

[0111] The difference from Example 1 is that lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and butadiene sulfone (Bds) are not added, that is, only NCM811+Super-P+PTFE are included. The preparation method is as follows:

[0112] Step 1: NCM811 (40 g) and conductive carbon black (8 g) were mixed in a high-speed disperser, and the mixture was uniformly mixed under strong mechanical stirring at a stirring speed of 2000 r / min for 35 min to obtain a mixture.

[0113] Step 2: Add polytetrafluoroethylene (10 g) to the mixture obtained in step 1 and mix evenly at a speed of 3000 r / min for 2 h.

[0114] Step 3: Place the mixture obtained in step 2 into a high-speed disperser at a speed of 3000 r / min for 2 h to obtain an electrode.

[0115] Step 4: Place the mixture obtained in step 3 into a mortar and grind it evenly for 20 minutes to form a thin film. Then place the obtained film into a roller press and roll it into a certain thickness. At a temperature of 100°C, adhere the film to the current collector to obtain a pole piece.

[0116] Example 3:

[0117] The charge and discharge test was carried out on the lithium / (NCM811+Super-P+PTFE) half-cell assembled with the electrode obtained in Comparative Example 1 and the lithium / (NCM811+Super-P+PTFE+LiTFSI+Bds) half-cell assembled with the electrode obtained in Example 1. The capacity-voltage curves obtained are shown in FIG. Figure 6 shown.

[0118] Depend on Figure 6 It can be seen that the lithium / (NCM811+Super-P+PTFE+LiTFSI+Bds) battery has a 188mAh g -1 The discharge specific capacity of the lithium / (NCM811+Super-P+PTFE) battery, on the other hand, shows rapid capacity decay and low coulombic efficiency in the voltage range of 2.5-4.4V at 0.1C. This shows that the addition of metal salts and hydrogen bond donors can solve the problems of unstable contact between the solid electrolyte and the electrode, slow ion migration in thick electrodes, and difficulty in electrolyte infiltration.

[0119] Example 4:

[0120] This embodiment provides a method for preparing a solid electrolyte membrane, comprising the following steps:

[0121] Step 1: Mix garnet oxide solid electrolyte (LLZTO, 20 g), lithium bis(trifluoromethanesulfonyl imide) (5 g) and polytetrafluoroethylene (5 g) in a high-speed disperser, and mix the mixture evenly under strong mechanical stirring at a speed of 3000 r / min for 1 h.

[0122] Step 2: Mix garnet oxide solid electrolyte (LLZTO, 20 g), butadiene sulfone (5 g) and polytetrafluoroethylene (5 g) in a high-speed disperser, and mix the mixture evenly under strong mechanical stirring at a speed of 3000 r / min for 1 h.

[0123] Step 3: Place the two mixtures obtained in step 1 and step 2 into a high-speed disperser at a speed of 3000 r / min for 1 hour.

[0124] Step 4: Place the mixture obtained in step 3 into a mortar and grind it evenly for 20 minutes to form a flexible film. Then, place the obtained film into a roller press and roll it into a certain thickness at a temperature of 100°C to obtain a solid electrolyte membrane.

[0125] Figure 7 This is an optical image of a solid electrolyte membrane synthesized from LLZTO, PTFE, LiTFSI, and Bds in Example 4 of the present invention.

[0126] Comparative Example 2:

[0127] The difference from Example 4 is that lithium bis(trifluoromethanesulfonyl imide) and diisobutylene sulfone are not added, and the garnet-type oxide solid electrolyte is directly used as the electrolyte membrane.

[0128] Example 5:

[0129] The charge and discharge tests were carried out on the assembled lithium / NCM811 battery (control group) assembled with the electrolyte membrane obtained in Comparative Example 2 and the assembled lithium / NCM811 battery (experimental group) assembled with the electrolyte membrane obtained in Example 4. The capacity-voltage curves obtained are shown in FIG. Figure 8 As shown, the left picture is the control group, and the right picture is the experimental group. Figure 8 It can be seen that in the voltage range of 2.5-4.4 V at 0.1C, the lithium / NCM811 battery in the experimental group has a capacity of 4.7 mAh cm in the second cycle. -1 , indicating that the battery prepared with the solid electrolyte obtained by adding lithium salt and hydrogen bond donor in the experimental group has better charge and discharge performance.

[0130] Example 6:

[0131] This embodiment provides a method for preparing a dry electrode, comprising the following steps:

[0132] Step 1: lithium iron phosphate (40 g) and conductive carbon black (8 g) were mixed in a high-speed disperser, and the mixture was uniformly mixed under strong mechanical stirring at a stirring speed of 2000 r / min for 35 min to obtain a mixture.

[0133] Step 2: Divide the mixture obtained in step 1 into two equal parts (24 g each), add lithium bis(trifluoromethanesulfonyl)imide (10 g) and polytetrafluoroethylene (5 g) into one part, and add butadiene sulfone (10 g) and polytetrafluoroethylene (5 g) into the other part, and mix them evenly at a speed of 3000 r / min for 2 h.

[0134] Step 3: Place the two mixtures obtained in step 2 into a high-speed disperser and mix them evenly at a speed of 3000 r / min for 2 h.

[0135] Step 4: Place the mixture obtained in step 3 into a mortar and grind it evenly for 20 minutes to form a flexible film. Then place the obtained film into a roller press and roll it into a certain thickness. At a temperature of 100°C, adhere the film to the current collector to obtain a pole piece.

[0136] The lithium (lithium iron phosphate + Super-P + PTFE + LiTFSI + Bds) half-cell assembled with the obtained electrode was tested for charge and discharge. The battery capacity was 161mAh g in the voltage range of 2.5-3.9V at 0.1C. -1 discharge capacity.

[0137] Example 7:

[0138] This embodiment provides a method for preparing a dry electrode, comprising the following steps:

[0139] Step 1: lithium iron phosphate (40 g) and conductive carbon black (8 g) were mixed in a high-speed disperser, and the mixture was uniformly mixed under strong mechanical stirring at a stirring speed of 2000 r / min for 35 min to obtain a mixture.

[0140] Step 2: Divide the mixture obtained in step 1 into two equal parts (24 g each), add lithium bis(fluorosulfonyl)imide (10 g) and polytetrafluoroethylene (5 g) into one part, and add butadiene sulfone (10 g) and polytetrafluoroethylene (5 g) into the other part, and mix them evenly at a speed of 3000 r / min for 2 h.

[0141] Step 3: Place the two mixtures obtained in step 2 into a high-speed disperser and mix them evenly at a speed of 3000 r / min for 2 h.

[0142] Step 4: Place the mixture obtained in step 3 into a mortar and grind it evenly for 20 minutes to form a flexible film. Then place the obtained film into a roller press and roll it into a certain thickness. At a temperature of 100°C, adhere the film to the current collector to obtain a pole piece.

[0143] The lithium (lithium iron phosphate + Super-P + PTFE + LiFSI + Bds) half-cell assembled with the obtained electrode was tested for charge and discharge. The battery had a capacity of 160mAh g in the voltage range of 2.5-3.9V at 0.1C. -1 discharge capacity.

[0144] Example 8:

[0145] This embodiment provides a method for preparing a dry electrode, comprising the following steps:

[0146] Step 1: Graphite (40 g) and conductive carbon black (8 g) were mixed in a high-speed disperser, and the mixture was uniformly mixed under strong mechanical stirring at a stirring speed of 2000 r / min for 35 min to obtain a mixture.

[0147] Step 2: Divide the mixture obtained in step 1 into two equal parts (24 g each), add lithium bis(trifluoromethanesulfonyl)imide (10 g) and polytetrafluoroethylene (5 g) into one part, and add butadiene sulfone (10 g) and polytetrafluoroethylene (5 g) into the other part, and mix them evenly at a speed of 3000 r / min for 2 h.

[0148] Step 3: Place the two mixtures obtained in step 2 into a high-speed disperser and mix them evenly at a speed of 3000 r / min for 2 h.

[0149] Step 4: Place the mixture obtained in step 3 into a mortar and grind it evenly for 20 minutes to form a flexible film. Then place the obtained film into a roller press and roll it into a certain thickness. At a temperature of 100°C, adhere the film to the current collector to obtain a pole piece.

[0150] The lithium (graphite + Super-P + PTFE + LiTFSI + Bds) half-cell assembled with the obtained electrode was tested for charge and discharge. The battery had a capacity of 350mAh g in the voltage range of 0.01-2V at 0.1C. -1 discharge capacity.

[0151] Example 9:

[0152] This embodiment provides a method for preparing a dry electrode, comprising the following steps:

[0153] Step 1: Mix the silicon-carbon material (50 g) and the conductive carbon black (8 g) in a high-speed disperser, and mix the mixture evenly under strong mechanical stirring at a stirring speed of 2000 r / min for 35 min.

[0154] Step 2: Divide the mixture obtained in step 1 into two equal parts (29 g each), add lithium bis(trifluoromethanesulfonyl)imide (10 g) and polytetrafluoroethylene (5 g), butadiene sulfone (10 g) and polytetrafluoroethylene (5 g) respectively, and mix them evenly at a speed of 3000 r / min for 2 h.

[0155] Step 3: Place the two mixtures obtained in step 2 into a high-speed disperser and mix them evenly at a speed of 3000 r / min for 2 h.

[0156] Step 4: Place the mixture obtained in step 3 into a mortar and grind it evenly for 20 minutes to form a flexible film. Then place the obtained film into a roller press and roll it into a certain thickness. At a temperature of 100°C, adhere the film to the current collector to obtain a pole piece.

[0157] The lithium (silicon carbon + Super-P + PTFE + LiTFSI + Bds) half-cell assembled with the obtained electrode was tested for charge and discharge. The battery capacity was 1100mAh g in the voltage range of 0.01-2V at 0.1C. -1 discharge capacity.

[0158] Example 10:

[0159] This embodiment provides a method for preparing a dry electrode, comprising the following steps:

[0160] Step 1: Pure silicon (20 g) and conductive carbon black (14 g) were mixed in a high-speed disperser, and the mixture was mixed evenly under strong mechanical stirring at a speed of 2000 r / min for 35 min.

[0161] Step 2: Divide the mixture obtained in step 1 into two equal parts (27 g each), add lithium bis(trifluoromethanesulfonyl)imide (10 g) and polytetrafluoroethylene (5 g), butadiene sulfone (10 g) and polytetrafluoroethylene (5 g) respectively, and mix them evenly at a speed of 3000 r / min for 2 h.

[0162] Step 3: Place the two mixtures obtained in step 2 into a high-speed disperser and mix them evenly at a speed of 3000 r / min for 2 h.

[0163] Step 4: Place the mixture obtained in step 3 into a mortar and grind it evenly for 20 minutes to form a flexible film. Then place the obtained film into a roller press and roll it into a certain thickness. At a temperature of 100°C, adhere the film to the current collector to obtain a pole piece.

[0164] The lithium (pure silicon + Super-P + PTFE + LiTFSI + Bds) half-cell assembled with the obtained electrode was tested for charge and discharge. The battery capacity was 3200mAh g in the voltage range of 0.01-2V at 0.1C. -1 discharge capacity.

[0165] Example 11:

[0166] This embodiment provides a method for preparing a dry electrode, which differs from Example 1 in that "butadiene sulfone" is replaced with "succinonitrile", and the rest is the same as Example 1.

[0167] The lithium (lithium iron phosphate + Super-P + PTFE + LiDFOB + SN) half-cell assembled with the obtained electrode was tested for charge and discharge. The battery capacity was 156.11 mAh g in the voltage range of 2.5 to 3.9 V at 0.1 C. -1 The discharge capacity of Figure 9 .

[0168] Example 12:

[0169] This embodiment provides a method for preparing a dry electrode, which differs from Example 1 in that "butadiene sulfone" is replaced with "propenyl-1,3-sultone" and is otherwise the same as Example 1.

[0170] The lithium (lithium iron phosphate + Super-P + PTFE + LiFSI + PES) half-cell assembled with the obtained electrode was tested for charge and discharge. The battery capacity was 157.34 mAh g in the voltage range of 2.5-3.9 V at 0.1 C. -1 The discharge capacity of Figure 10 .

[0171] Example 13:

[0172] This embodiment provides a method for preparing a dry electrode, which differs from Example 1 in that "butadiene sulfone" is replaced with "tetrahydropyran" and is otherwise the same as Example 1.

[0173] The lithium (lithium iron phosphate + Super-P + PTFE + LiTFSI + THP) half-cell assembled with the obtained electrode was tested for charge and discharge. The battery capacity was 161.23 mAh g in the voltage range of 2.5-3.9 V at 0.1 C. -1 The discharge capacity of Figure 11 .

[0174] Example 14:

[0175] This embodiment provides a method for preparing a dry electrode, which differs from Example 1 in that "butadiene sulfone" is replaced with "N-methyltrifluoroacetamide" and is otherwise the same as Example 1.

[0176] The lithium (lithium iron phosphate + Super-P + PTFE + LiTFSI + NMTFA) half-cell assembled with the obtained electrode was tested for charge and discharge. The battery capacity was 156.68 mAh g in the voltage range of 2.5 to 3.9 V at 0.1 C. -1 The discharge capacity of Figure 12 .

[0177] Example 15:

[0178] This embodiment provides a method for preparing a dry electrode, which differs from Example 1 in that "butadiene sulfone" is replaced with "dimethylmalononitrile" and is otherwise the same as Example 1.

[0179] The lithium (lithium iron phosphate + Super-P + PTFE + LiTFSI + DMMN) half-cell assembled with the obtained electrode was tested for charge and discharge. The battery capacity was 160.57 mAh g in the voltage range of 2.5-3.8 V at 0.1 C. -1 The discharge capacity of Figure 13 .

[0180] Example 16:

[0181] This embodiment provides a method for preparing a dry electrode, which differs from Example 1 in that "butadiene sulfone" is replaced with "N-methylacetamide" and is otherwise the same as Example 1.

[0182] The lithium (lithium iron phosphate + Super-P + PTFE + LiTFSI + NMAC) half-cell assembled with the obtained electrode was tested for charge and discharge. The battery capacity was 160.82 mAh g in the voltage range of 2.5-3.9 V at 0.1 C. -1 The discharge capacity of Figure 14 .

[0183] Example 17:

[0184] This embodiment provides a method for preparing a solid electrolyte membrane, which differs from Example 4 in that "LLZTO" is replaced with "LLZO" and is otherwise the same as Example 4.

[0185] The lithium / NCM811 half-cell assembled with the obtained solid electrolyte membrane was subjected to charge and discharge tests. The battery capacity was 185.33 mAh g in the voltage range of 2.5 to 4.4 V at 0.1 C. -1 The discharge capacity of Figure 15 .

[0186] Example 18:

[0187] This embodiment provides a method for preparing a solid electrolyte membrane. The difference from embodiment 4 is that “LLZTO” is replaced by “Li3Zr2Si2PO 12 ", and the rest are the same as in Example 4.

[0188] The lithium / NCM811 half-cell assembled with the obtained solid electrolyte membrane was subjected to charge and discharge tests. The battery capacity was 176.36 mAh g in the voltage range of 2.5 to 4.4 V at 0.1 C. -1 The discharge capacity of Figure 16 .

[0189] Example 19:

[0190] This embodiment provides a method for preparing a solid electrolyte membrane. The difference from embodiment 4 is that “LLZTO” is replaced by “Li 1.5 Al 0.5 Ge 1.5 (PO4)3", and the rest is the same as in Example 4.

[0191] The lithium / NCM811 half-cell assembled with the obtained solid electrolyte membrane was subjected to charge and discharge tests. The battery capacity was 172.67 mAh g in the voltage range of 2.5-4.4 V at 0.1 C. -1 discharge capacity.

[0192] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A solid electrolyte membrane, characterized in that The solid electrolyte membrane comprises the following components: a solid electrolyte, a metal salt, a hydrogen bond donor, and a binder, wherein the metal salt and the hydrogen bond donor form an electrolyte having a eutectic structure through intermolecular coordination interactions; The metal salt includes a lithium salt; The hydrogen bond donor is at least one of hydroxyl compounds, carboxylic acid compounds, nitrile compounds, imidazole compounds, pyridine compounds, amide compounds, sulfone compounds, pyrrole compounds, amino acid compounds and ammonium salts.

2. The solid electrolyte membrane according to claim 1, characterized in that The components in the solid electrolyte membrane are calculated by mass fraction as follows: solid electrolyte 60% to 90%, metal salt 1% to 10%, hydrogen bond donor 1% to 15%, and binder 1% to 20%.

3. The solid electrolyte membrane according to claim 1, wherein Among the hydrogen bond donors, the hydroxyl compounds are ethylene glycol, 1,2-propylene glycol, 2-cyanoethanol, and phenol; the carboxylic acid compounds are formic acid, acetic acid, glutamic acid, glycolic acid, malonic acid, oxalic acid, and levulinic acid; the nitrile compounds are succinonitrile, acetonitrile, propionitrile, dimethylmalononitrile, tricyanomethane, tetracyanoethylene, and cyanoacetic acid; the imidazole compounds are imidazole, 2-methylimidazole, 1,2-dimethylimidazole, 4(5)-hydroxyimidazole, imidazole hydrochloride, imidazole-4-carboxylic acid, N-methylimidazole, 2-aminoimidazole, and 2-imidazolidinone; the pyridine compounds are The compound is 2-cyanopyridine; the amide compound is N-methylacetamide, N-methyltrifluoroacetamide, N-ethylacetamide, N-methylpropionamide, N-benzylacetamide, acetamide, formamide, oxalamide, caprolactam, urea, N,N-dimethylpropyleneurea, tetramethylurea, trifluoroacetamide, 1,3-dimethylurea; the sulfone compound is butadiene sulfone; the pyrrole compound is 2-pyrrolidine and tetrahydropyran; the amino acid compound is N-acetylglycine; the ammonium salt is (propenyl-1,3-sultone, 2-hydroxyethyl)-trimethylammonium chloride; The lithium salt is at least one of lithium nitrate, lithium bis(fluorosulfonyl imide), lithium bis(trifluoromethanesulfonyl imide), lithium hexafluorophosphate, lithium difluorooxalatoborate, lithium perchlorate, lithium hexafluoroarsenate, lithium difluorophosphate, lithium trifluoromethanesulfonate, lithium bis(oxalatoborate) and lithium tetrafluoroborate; The solid electrolyte is at least one of a sodium ultrafast ion conductor, a garnet-type solid electrolyte, an inorganic perovskite-type electrolyte, and a LiPON film; The binder is at least one of sodium carboxymethyl cellulose, styrene-butadiene rubber, sodium carboxymethyl cellulose, polytetrafluoroethylene, polyvinylidene fluoride, and polyethylene oxide.

4. A method for preparing a solid electrolyte membrane according to any one of claims 1 to 3, comprising the following steps: uniformly mixing the solid electrolyte, the metal salt and the binder to obtain a first mixture; uniformly mixing the remaining solid electrolyte, the hydrogen bond donor, and the remaining binder to obtain a second mixture; The first mixture and the second mixture are mixed uniformly, ground, and rolled to obtain a solid electrolyte membrane.

5. A dry electrode, characterized in that: The electrode comprises the following components: an active material, a conductive agent, a binder, a metal salt and a hydrogen bond donor, wherein the metal salt and the hydrogen bond donor form an electrolyte having a eutectic structure through intermolecular coordination interactions; The active material is a positive electrode active material or a negative electrode active material; The metal salt includes a lithium salt; The hydrogen bond donor is at least one of hydroxyl compounds, carboxylic acid compounds, nitrile compounds, imidazole compounds, pyridine compounds, amide compounds, sulfone compounds, pyrrole compounds, amino acid compounds and ammonium salts.

6. The electrode according to claim 5, characterized in that The components in the electrode are calculated by mass fraction as follows: active material 50% to 90%, conductive agent 2% to 12%, binder 1% to 15%, lithium salt 1% to 15%, and hydrogen bond donor 1% to 15%.

7. The electrode according to claim 5, characterized in that Among the hydrogen bond donors, the hydroxyl compounds are ethylene glycol, 1,2-propylene glycol, 2-cyanoethanol, and phenol; the carboxylic acid compounds are formic acid, acetic acid, glutamic acid, glycolic acid, malonic acid, oxalic acid, and levulinic acid; the nitrile compounds are succinonitrile, acetonitrile, propionitrile, dimethylmalononitrile, tricyanomethane, tetracyanoethylene, and cyanoacetic acid; the imidazole compounds are imidazole, 2-methylimidazole, 1,2-dimethylimidazole, 4(5)-hydroxyimidazole, imidazole hydrochloride, imidazole-4-carboxylic acid, N-methylimidazole, 2-aminoimidazole, and 2-imidazolidinone; the pyridine compounds are The compounds are 2-cyanopyridine and tetrahydropyran; the amide compounds are N-methylacetamide, N-methyltrifluoroacetamide, N-ethylacetamide, N-methylpropionamide, N-benzylacetamide, acetamide, formamide, oxalamide, caprolactam, urea, N,N-dimethylpropyleneurea, tetramethylurea, trifluoroacetamide, and 1,3-dimethylurea; the sulfone compound is butadiene sulfone; the pyrrole compound is 2-pyrrolidine; the amino acid compound is N-acetylglycine; the ammonium salts are allyl-1,3-sultone and (2-hydroxyethyl)-trimethylammonium chloride; The lithium salt is at least one of lithium nitrate, lithium bis(fluorosulfonyl imide), lithium bis(trifluoromethanesulfonyl imide), lithium hexafluorophosphate, lithium difluorooxalatoborate, lithium perchlorate, lithium hexafluoroarsenate, lithium difluorophosphate, lithium trifluoromethanesulfonate, lithium bis(oxalatoborate) and lithium tetrafluoroborate.

8. The electrode according to claim 5, characterized in that The positive electrode active material is at least one of sulfur, polyacrylonitrile, lithium iron phosphate, lithium cobalt oxide, nickel-cobalt-manganese / nickel-cobalt-aluminum ternary positive electrode and lithium-rich manganese-based positive electrode material; The negative electrode active material is at least one of metallic lithium, silicon-carbon negative electrode material, lithium titanate, graphite, and pure silicon; The conductive agent is at least one of superconductive carbon black, graphite powder, carbon nanotubes, and vapor-grown carbon fibers; The binder is at least one of sodium carboxymethyl cellulose, styrene-butadiene rubber, sodium carboxymethyl cellulose, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and polyethylene oxide.

9. The method for preparing an electrode according to any one of claims 5 to 8, characterized in that: The following steps are involved: mixing the active material and the conductive carbon black to obtain a third mixture; The third mixture is divided into two parts, a metal salt and a binder are added to one part of the third mixture, and the mixture is mixed to obtain a fourth mixture; a hydrogen bond donor and the remaining binder are added to the other part of the third mixture, and the mixture is mixed to obtain a fifth mixture; The fourth mixture and the fifth mixture are mixed uniformly, ground, and pressed to obtain an electrode.

10. A deep eutectic-assisted lithium battery, characterized in that: It comprises the solid electrolyte membrane according to any one of claims 1 to 3 and / or the electrode according to any one of claims 5 to 8.

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