Anode coatings for solid-state Li-ion batteries

Abstract

The present invention generally relates to the field of electrical energy storage in rechargeable accumulators of the Li-ion type. More specifically, the present invention relates to an anode coating for a fully solid-state Li-ion battery. The present invention also relates to a method for the preparation of said coating. The present invention also relates to an anode coated with said coating, a method for producing such an anode and also to a Li-ion accumulator comprising such an anode.

Description

[Technical field]

[0001] The present invention generally relates to the field of electrical energy storage in rechargeable accumulators of the Li-ion type. More specifically, the present invention relates to an anode coating for all-solid-state Li-ion batteries. The present invention also relates to a method for preparing said coating. The present invention also relates to an anode coated with this coating, a method for producing such an anode and also to a Li-ion accumulator comprising such an anode. [Background technology]

[0002] Lithium batteries can be used as power sources for a variety of electronic devices, from mobile phones, laptop computers and small household electronics devices to vehicles and even large-capacity energy storage devices, and the demand for lithium batteries is constantly expanding.

[0003] Conventional lithium storage batteries generally use organic-containing liquid electrolytes that advantageously have high ionic conductivity but require additional safety devices due to the risk of liquid leakage, fire, or explosion at high temperatures.

[0004] To address the safety issues associated with liquid electrolytes, fully solid-state batteries using solid electrolytes have been developed in recent years.

[0005] An all-solid-state battery generally comprises a positive electrode, a solid electrolyte, and a negative electrode. The positive electrode includes a positive electrode active material and a solid electrolyte, and further includes an electronically conductive material and a binder. The solid electrolyte includes one or more elements from the following list: a polymer, a plasticizer, a lithium salt, an inorganic particle, and an ionic liquid. The negative electrode includes a negative electrode active material and a solid electrolyte, similar to the positive electrode, and further includes a conductive material and a binder.

[0006] However, currently there are no solid electrolytes that meet the specifications for bulk applications of solid-state batteries, due to the general difficulty in combining ionic conductivity, electrochemical stability, mechanical strength, and compatibility with anode or cathode materials for solid electrolytes.

[0007] In particular, examples may include inorganic compounds that exhibit very high ionic conductivity but electrochemical instability with respect to potentials at the anode and high potentials at the cathode. (Y. Zhu, ACS Appl. Mater. Interfaces, 2015, 7, 23685-23693) There remains a need to develop solutions that allow the anode to be compatible with the solid electrolyte in solid-state Li-ion batteries. In particular, the problem of the variation in the volume of the anode during charge and discharge cycles needs to be solved. Finally, in the particular case of lithium metal anodes, there is a need to provide an anode protected by effective means from the formation of dendrites. [Prior art documents] [Non-patent literature]

[0008] [Non-Patent Document 1] Y. Zhu,ACS Appl.Mater.Interfaces,2015,7,23685-23693 Summary of the Invention [Problem to be solved by the invention]

[0009] The object of the present invention is therefore to provide a coating that can be applied directly to a Li-ion battery anode and that then allows a physical separation between the solid electrolyte and the electrode active material.The present invention therefore provides an anode comprising a first layer of a conventional anode and a second layer of an anode coating according to the present invention.

[0010] The present invention also aims to provide a method for producing said anode coating.Finally, the present invention relates to an anode exhibiting such a coating and to a method for producing such an anode.

[0011] Finally, the present invention aims to provide a rechargeable Li-ion accumulator comprising such an anode. [Means for solving the problem]

[0012] The technical solution proposed by the present invention is to provide an anode coating that makes the cathode compatible with the solid electrolyte in an all-solid-state battery.

[0013] The present invention first provides a method for producing a a. one or more poly(vinylidene fluorides); b. a lithium salt; c. Conductive additives The anode coating comprises:

[0014] The invention also relates to a method for producing an anode coating from an ink obtained by mixing all the constituents of the coating.

[0015] The present invention also relates to an anode for a lithium-ion battery, which consists of a layer of negative active material coated with a coating layer according to the invention.

[0016] The present invention also provides a method for producing a Li-ion battery anode, the method comprising the steps of: providing an anode; depositing a coating layer on said anode; The present invention relates to a method comprising the steps of:

[0017] Another subject of the invention is a Li-ion accumulator comprising a negative electrode, a positive electrode and an all-solid-state electrolyte, the anode being as defined above.

[0018] The present invention makes it possible to overcome the drawbacks of the state of the art: it provides an ionically conductive coating that has a uniform distribution of its dielectric constant while maintaining sufficient mechanical strength to avoid the formation of dendrites, which coating demonstrates good reduction stability and good flexibility, making it possible to withstand variations in the anode volume during charge and discharge cycles.

[0019] In the particular case of lithium anodes, the coating according to the invention makes it possible to prevent the growth of dendrites which may cause short circuits, and the good homogeneity of the dielectric constant makes it possible to avoid the formation of regions with a high concentration of lithium ions. This coating also makes it possible to form a stable and low resistivity solid electrolyte interface (SEI) on the lithium metal, thereby improving the performance and lifetime of the all-solid-state battery. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The invention will now be explained in more detail, without being limiting, in the following description.

[0021] According to a first aspect, the present invention provides a method for producing a composition comprising: a. one or more poly(vinylidene fluorides) (component A); b. at least one lithium salt (component B); c. at least one conductive additive (component C); The anode coating comprises:

[0022] According to various embodiments, the coating comprises the following properties when properly combined, with amounts given by weight unless otherwise specified:

[0023] Ingredient A The semi-crystalline fluoropolymers used in the present invention are polymers based on vinylidene difluoride, commonly referred to by the abbreviation PVDF.

[0024] According to one embodiment, the PVDF is a poly(vinylidene fluoride) homopolymer or a mixture of vinylidene fluoride homopolymers.

[0025] According to one embodiment, the PVDF is a poly(vinylidene fluoride) homopolymer or a copolymer of vinylidene difluoride and at least one comonomer that is compatible with vinylidene difluoride.

[0026] According to one embodiment, the PVDF is semi-crystalline.

[0027] Comonomers compatible with vinylidene difluoride can be halogenated (fluorinated, chlorinated or brominated) or non-halogenated.

[0028] Examples of suitable fluorinated comonomers are vinyl fluoride, tetrafluoroethylene, hexafluoropropylene, trifluoropropene, in particular 3,3,3-trifluoropropene, tetrafluoropropene, in particular 2,3,3,3-tetrafluoropropene or 1,3,3,3-tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, pentafluoropropene, in particular 1,1,3,3,3-pentafluoropropene or 1,2,3,3,3-pentafluoropropene, perfluoroalkyl vinyl ethers, in particular those of the general formula Rf-O-CF-CF2, where Rf is an alkyl group, preferably a C1-C4 alkyl group (preferred examples are perfluoro(propyl vinyl ether) and perfluoro(methyl vinyl ether)).

[0029] The fluorinated comonomer may contain a chlorine atom or a bromine atom. The fluorinated comonomer may be selected in particular from bromotrifluoroethylene, chlorofluoroethylene, chlorotrifluoroethylene and chlorotrifluoropropene. Chlorofluoroethylene may refer to either 1-chloro-1-fluoroethylene or 1-chloro-2-fluoroethylene. The 1-chloro-1-fluoroethylene isomer is preferred. The chlorotrifluoropropene is preferably 1-chloro-3,3,3-trifluoropropene or 2-chloro-3,3,3-trifluoropropene.

[0030] The VDF copolymer may also contain non-halogenated monomers such as ethylene and / or acrylic or methacrylic comonomers.

[0031] The fluoropolymer preferably contains at least 50 mol % vinylidene difluoride.

[0032] According to one embodiment, the PVDF is a copolymer of vinylidene fluoride (VDF) and hexafluoropropylene (HFP) (P(VDF-HFP)), with the weight percentage of hexafluoropropylene monomer units being between 2% and 23% by weight, preferably between 4% and 15% by weight, based on the weight of the copolymer.

[0033] According to one embodiment, the PVDF is a mixture of poly(vinylidene fluoride) homopolymer and VDF-HFP copolymer.

[0034] According to one embodiment, the PVDF is a copolymer of vinylidene fluoride and tetrafluoroethylene (TFE).

[0035] According to one embodiment, the PVDF is a copolymer of vinylidene fluoride and chlorotrifluoroethylene (CTFE).

[0036] According to one embodiment, the PVDF is a VDF-TFE-HFP terpolymer. According to one embodiment, the PVDF is a VDF-TrFE-TFE terpolymer (TrFE is trifluoroethylene). In these terpolymers, the weight content of VDF is at least 10% and the comonomers are present in various proportions.

[0037] According to one embodiment, the PVDF is a mixture of two or more PVDF-HFP copolymers. The presence of a comonomer based on HFP makes it possible to improve the chemical stability of the coating towards lithium metal.

[0038] According to one embodiment, the PVDF comprises monomer units having at least one of the following functional groups: carboxylic acid, carboxylic anhydride, carboxylic ester, epoxy (such as glycidyl), amide, hydroxyl, carbonyl, mercapto, sulfide, oxazoline, phenol, ester, ether, siloxane, sulfonic acid, sulfuric acid, phosphoric acid or phosphonic acid. The functional groups are introduced by chemical reaction, which may be grafting or copolymerization, of a fluorinated monomer with a monomer having at least one of the functional groups and a vinyl functional group capable of copolymerizing with the fluorinated monomer, according to techniques well known to those skilled in the art.

[0039] According to one embodiment, the functional group has a carboxylic acid functionality which is a (meth)acrylic acid type group selected from acrylic acid, methacrylic acid, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate and hydroxyethylhexyl (meth)acrylate.

[0040] According to one embodiment, the unit having carboxylic acid functionality further comprises a heteroatom selected from oxygen, sulfur, nitrogen and phosphorus.

[0041] According to one embodiment, the functionality is introduced by a transfer agent used during the synthesis process. The transfer agent is a polymer with a molar mass of less than or equal to 20000 g / mol, carrying functional groups selected from the following groups: carboxylic acid, carboxylic anhydride, carboxylic ester, epoxy (such as glycidyl), amide, hydroxyl, carbonyl, mercapto, sulfide, oxazoline, phenol, ester, ether, siloxane, sulfonic acid, sulfuric acid, phosphoric acid or phosphonic acid. An example of this type of transfer agent is an acrylic acid oligomer.

[0042] The content of functional groups in PVDF is at least 0.01 mol %, preferably at least 0.1 mol % and at most 15 mol %, preferably at most 10 mol %.

[0043] The PVDF is preferably of high molecular weight. The term "high molecular weight" as used herein is understood to mean a PVDF having a melt viscosity of more than 100 Pa.s, preferably more than 500 Pa.s, more preferably more than 1000 Pa.s, advantageously more than 2000 Pa.s. The viscosity is measured according to standard ASTM D3825 using a capillary or parallel plate rheometer at 232°C for 100 s. -1 The shear gradient is measured at 100 nm. The two methods give similar results.

[0044] The PVDF homopolymers and VDF copolymers used in the present invention can be obtained by known polymerization methods, such as emulsion polymerization.

[0045] According to one embodiment, they are prepared by an emulsion polymerization process in the absence of fluorinated surfactants.

[0046] Polymerization of PVDF generally results in a latex having a solids content of 10% to 60% by weight, preferably 10% to 50% by weight, and a weight average particle size of less than 1 micrometer, preferably less than 1000 nm, preferably less than 800 nm and more preferably less than 600 nm. The weight average size of the particles is generally at least 10 nm, preferably at least 50 nm, and advantageously the average size is in the range of 100 to 400 nm. The polymer particles may form weak agglomerates, called secondary particles, whose weight average size is less than 5000 μm, preferably less than 1000 μm, advantageously 1 to 80 micrometers and preferably 2 to 50 micrometers. The weak agglomerates can be broken down into individual particles during formulation and application to a substrate.

[0047] According to some embodiments, the PVDF homopolymer and VDF copolymer are composed of bio-based VDF. The term "bio-based" means "obtained from biomass". This makes it possible to improve the ecological footprint of the coating. Bio-based VDF is according to the standard NF EN 16640 14 It may be characterized by a content of at least 1 atomic % of renewable carbon, i.e. carbon of natural origin derived from biological material or biomass, as determined by the content of C. The term "renewable carbon" indicates that the carbon is of natural origin and derived from biological material (or biomass), as shown below. According to some embodiments, the biocarbon content of the VDF may be greater than 5%, preferably greater than 10%, preferably greater than 25%, preferably greater than 33%, preferably greater than 50%, preferably greater than 66%, preferably greater than 75%, preferably greater than 90%, preferably greater than 95%, preferably greater than 98%, preferably greater than 99%, advantageously equal to 100%.

[0048] Component B As non-limiting examples, the lithium salt (or lithium salts) is selected from LiPF6 (lithium hexafluorophosphate), LiFSI (lithium bis(fluorosulfonyl)imide), TFSI (lithium bis(trifluoromethylsulfonyl)imide), LiTDI (lithium 2-trifluoromethyl-4,5-dicyanoimidazolate), LiPOF2, LiB(C2O4)2, LiF2B(C2O4)2, LiBF4, LiNO3, LiClO4, and mixtures of two or more of the listed salts.

[0049] Component C The conductive additive may be an organic molecule or a mixture of organic molecules capable of swelling the fluoropolymer without dissolving it and having a dielectric constant greater than 1. According to one embodiment, component C is selected from linear or cyclic ethers, esters, lactones, nitriles, carbonates and ionic liquids.

[0050] As non-limiting examples, among the ethers, mention may be made of linear or cyclic ethers such as dimethoxyethane (DME), the methyl ethers of oligoethylene glycols of 2 to 5 oxyethylene units, dioxolane, dioxane, dibutyl ether, tetrahydrofuran, and mixtures thereof.

[0051] Among the esters, mention may be made of phosphates or sulfites, for example methyl formate, methyl acetate, methyl propionate, ethyl acetate, butyl acetate, gamma-butyrolactone or mixtures thereof.

[0052] Among the lactones, mention may in particular be made of cyclohexanone.

[0053] Among the nitriles, mention may be made, for example, of acetonitrile, pyruvonitrile, propionitrile, methoxypropionitrile, dimethylaminopropionitrile, butyronitrile, isobutyronitrile, valeronitrile, pivalonitrile, isovaleronitrile, glutaronitrile, methoxyglutaronitrile, 2-methylglutaronitrile, 3-methylglutaronitrile, adiponitrile, malononitrile and mixtures thereof.

[0054] For example, among carbonates, ethylene carbonate (EC) (CAS: 96-49-1), propylene carbonate (PC) (CAS: 108-32-7), butylene carbonate (BC) (CAS: 4437-85-8), dimethyl carbonate (DMC) (CAS: 616-38-6), diethyl carbonate (DEC) (CAS: 105-58-8), ethyl methyl carbonate (EMC) (CAS: 623-53-0), diphenyl carbonate (CAS: 102-09-0), methyl phenyl carbonate (CAS: 102-09-0), cyclic carbonates such as ethyl propyl carbonate (CAS:13509-27-8), dipropyl carbonate (DPC) (CAS:623-96-1), methyl propyl carbonate (MPC) (CAS:1333-41-1), ethyl propyl carbonate (EPC), vinylene carbonate (VC) (CAS:872-36-6), fluoroethylene carbonate (FEC) (CAS:114435-02-8), trifluoropropylene carbonate (CAS:167951-80-6) or mixtures thereof.

[0055] Among the ionic liquids, mention may in particular be made of EMIM:FSI, PYR:FSI, EMIM:TFSI, PYR:TFSI, EMIM:BOB, PYR:BOB, EMIM:TDI, PYR:TDI, EMIM:BF4 or PYR:BF4.

[0056] Composition by weight of the anode coating according to the invention: - component A having a weight ratio of 20% to 80%, - component B having a weight ratio of 1% to 40%, -Component C having a weight ratio of 2% to 50% (However, the total of these percentages is 100%) has.

[0057] The invention also relates to a method for producing said anode coating by the solvent route from an ink obtained by mixing all the constituents of the coating in a solvent.

[0058] The inks making it possible to prepare the coatings can be produced by any type of mixer known to those skilled in the art, such as planetary mixers, centrifuges, orbital mixers, stirrer shafts or Ultra-Turrax. The different constituents of the ink are not added in a strict order. The inks can be produced at different temperatures ranging from ambient temperature up to the boiling point of the solvent used to produce the ink.

[0059] The solvent used is preferably a polar solvent with a Hansen parameter greater than 2. Non-limiting examples include acetone, triethyl acetyl citrate (TEAC), γ-butyrolactone (GBL), cyclohexanone (CHO), cyclopentanone (CPO), dibutyl phthalate (DBP), dibutyl sebacate (DBS), diethyl carbonate (DEC), diethyl phthalate (DEP), dihydrolevoglucosenone (Cyrene), dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dimethylsulfoxide (DMSO), 1,4-dioxane, 3-heptanone, heptane, among others. Examples of the solvents that may be mentioned include heptanemethylphosphoramide (HMPA), 3-hexanone, methyl ethyl ketone (MEK), N-methyl-2-pyrrolidinone (NMP), 3-octanone, 3-pentanone, propylene carbonate (PC), tetrahydrofuran (THF), tetramethylurea (TMU), triacetin, triethyl citrate (TEC), triethyl phosphate (TEP), trimethyl phosphate (TMP), N,N,N',N'-tetrabutylsuccinamide (TBSA) or a mixture of two or more of the mentioned solvents.

[0060] According to one embodiment, the porosity of the coated anode according to the invention is less than 10%, preferably less than 5%.

[0061] The porosity of the coated electrode (CE) is obtained according to the following calculation described in the publication by M. Cai, Nature Communications, 10, 2019, 4597:

[0062]

number

[0063]

number

[0064] The thickness of this coating may range from 0.1 to 100 μm, preferentially from 0.1 to 50 μm and more preferentially from 0.1 to 35 μm.

[0065] The present invention also relates to an anode for an all-solid-state lithium-ion battery comprising, preferably consisting of, an active material coated with a coating layer according to the invention, preferably said active material of the anode being deposited on a metal support.

[0066] According to one embodiment, the active material in the negative electrode is graphite, Li4Ti5O 12 The lithium ion exchange material is selected from lithium titanates of the type, titanium oxide TiO2, silicon or lithium / silicon alloys, tin oxide, lithium intermetallic compounds, lithium metal, or mixtures thereof.

[0067] The active material, apart from the lithium metal, is mixed with an electronic conductive material and a binder.

[0068] The electronically conductive materials are selected from carbon black, natural or synthetic graphite, carbon fibres, carbon nanotubes, metal fibres and powders and conductive metal oxides. Preferentially, they are selected from carbon black, natural or synthetic graphite, carbon fibres and carbon nanotubes.

[0069] The binder used to manufacture the anode is a polymer selected from polyolefins (e.g., polyethylene or polypropylene), fluoropolymers capable of exhibiting acid functionality (PVDF), polyacrylic acid (PAA), polyacrylonitrile (PAN), cellulosic polymers, polyphenylsulfone, polyethersulfone, phenolic resins, vinyl ester resins, epoxy resins, PTFE, or liquid crystal polymers.

[0070] The anode thus comprises, preferably consists of, an active material coated with a coating layer according to the invention comprising, preferably consisting of, a) at least one poly(vinylidene fluoride) (component A) and b) at least one lithium salt (component B) and at least one conductive additive (component C). Preferably, the anode has a porosity as defined in the present application.

[0071] The present invention also provides a method for producing a Li-ion battery anode, the method comprising the steps of: providing an anode; depositing on said anode a coating layer according to the invention. The present invention relates to a method comprising the steps of:

[0072] The present invention therefore provides a negative electrode comprising, and preferably consisting of, a metal support on which is deposited an active material coated with a coating layer according to the present invention comprising, and preferably consisting of, a) at least one poly(vinylidene fluoride) (component A), and b) at least one lithium salt (component B) and at least one conductive additive (component C).

[0073] This coating can be produced by any deposition method known to those skilled in the art, such as solvent route coating, dip-pulling, centrifugal coating, spray coating or calendaring coating, etc. These deposition techniques can be carried out at different temperatures that can range from 5° C. up to 180° C.

[0074] The metal support of the anode is generally made of copper. The metal support may be surface-treated and may have a conductive primer with a thickness of 5 μm or more. The support may also be a woven or non-woven fabric made of carbon fiber.

[0075] Another subject of the invention is an all-solid-state Li-ion accumulator comprising a negative electrode, a positive electrode and an all-solid-state electrolyte, the anode being as defined above.

[0076] According to one embodiment, the cathode of the cell is also coated with a coating layer according to the present invention. EXAMPLES

[0077] The following examples illustrate the scope of the invention without, however, limiting it.

[0078] Preparation of fluoropolymer (FP) solutions: 14.992 g of VDF-HFP copolymer with a weight content of 23% HFP is dissolved in 85.753 g of acetone using a planetary mixer at 2000 rpm for 6 times 1 min in order to completely dissolve.

[0079] Preparation of coating ink I: FP / LiFSI / S1 60 / 20 / 20 0.441 g of LiFSI is dissolved in 0.449 g of tetraethylene glycol dimethyl ether (CAS 143-24-8) using a magnetic stirrer for 10 minutes at 21° C. Then 8.826 g of a 15% solution of FP in acetone is added.

[0080] Preparation of Coating Ink II: FP / LiFSI / MPCN 60 / 20 / 20 0.3986 g of LiFSI is dissolved in 0.3986 g of methoxypropionitrile (CAS 110-67-8) using a magnetic stirrer for 10 minutes at 21° C. Then 7.972 g of a 15% solution of FP in acetone is added.

[0081] Preparation of Coating Ink III: FP / LiFSI / S1 40 / 30 / 30 0.528 g of LiFSI is dissolved in 0.528 g of tetraethylene glycol dimethyl ether (CAS 143-24-8) using a magnetic stirrer for 10 minutes at 21° C. Then 4.675 g of a 15% solution of FP in acetone is added.

[0082] Coating of lithium metal with Ink III: Ink III is coated onto a 200 μm thick lithium metal foil using a coating blade. The thickness of the deposited wet film is 50 μm. After drying for 2 hours at ambient temperature, the thickness of the deposited film is measured to be 38 μm. The electrode is then calendered to obtain a 2 μm deposit on the lithium metal. The ionic conductivity is measured by impedance spectroscopy. The value obtained is 0.553 mS / cm.

[0083] Dendrite Testing: A dendrite test is carried out to compare the coating on Li metal obtained with Ink III with a standard liquid electrolyte.

[0084] method The method consists of charging and discharging a symmetric Li metal / Li metal cell, then measuring the potential of the cell: this potential is proportional to the surface area of ​​the electrode, so the appearance of dendrites causes an increase in potential.

[0085] System used : Cathode: Coated or uncoated lithium metal Anode: Lithium metal The battery is charged using a positive current of 0.25 mA to an energy density of 0.25 mAh. The battery is then discharged using a negative current of 0.25 mA to an energy density of 0.25 mAh.

[0086] For liquid electrolyte, the porous PE separator is immersed in an electrolyte solution containing 1M LiFSI in EC / EMC 3 / 7 volume ratio.

[0087] Table 1 shows the time required for the initial potential of the battery to double.

[0088] [Table 1]

Claims

1. a. at least one poly(vinylidene fluoride) (PVDF) (Component A); b. at least one lithium salt (Component B); c. at least one conductive additive (Component C) comprising an anode coating.

2. The coating according to claim 1, wherein Component A is selected from a poly(vinylidene fluoride) homopolymer and a copolymer of vinylidene difluoride and at least one comonomer selected from the list of vinyl fluoride, tetrafluoroethylene, hexafluoropropylene, 3,3,3-trifluoropropene, 2,3,3,3-tetrafluoropropene, 1,3,3,3-tetrafluoropropene, hexafluoroisobutylene, perfluorobutylethylene, 1,1,3,3,3-pentafluoropropene, 1,2,3,3,3-pentafluoropropene, perfluoro(propyl vinyl ether), perfluoro(methyl vinyl ether), bromotrifluoroethylene, chlorofluoroethylene, chlorotrifluoroethylene, chlorotrifluoropropene and ethylene, and mixtures thereof.

3. The coating according to claim 1, wherein the PVDF comprises monomer units having at least one of the following functional groups: carboxylic acid, carboxylic anhydride, carboxylic ester, epoxy (such as glycidyl), amide, hydroxyl, carbonyl, mercapto, sulfide, oxazoline, phenol, ester, ether, siloxane, sulfonic acid, sulfuric acid, phosphoric acid or phosphonic acid.

4. Said Component B is LiPF ６ (lithium hexafluorophosphate), LiFSI (lithium bis(fluorosulfonyl)imide), TFSI (lithium bis(trifluoromethylsulfonyl)imide), LiTDI (lithium 2-trifluoromethyl-4,5-dicyanoimidazolate), LiPOF ２ , LiB(C ２ O ４ ) ２ , LiF ２ B(C ２ O ４ ) ２ , LiBF ４ , LiNO ３ , LiClO ４ and the coating according to claim 1, selected from mixtures of two or more of the salts listed.

5. The coating according to claim 1, wherein Component C is selected from linear or cyclic ethers, esters, lactones, nitriles, carbonates and ionic liquids.

6. The coating according to claim 1, having a thickness in the range of 0.1 to 100 μm, preferably 0.1 to 50 μm and more preferably 0.1 to 35 μm.

7. The following weight composition: - Component A in a ratio of 20% to 80%; - Component B in a ratio of 1% to 40%; - Component C in a ratio of 2% to 50% (wherein the sum of these ratios is 100%) comprising the coating according to claim 1.

8. A method for producing the anode coating according to any one of claims 1 to 7 from an ink obtained by mixing all the constituent substances of the coating in a solvent.

9. The method according to claim 8, wherein the solvent is selected from the list of acetone, triethylacetyl citrate, γ-butyrolactone, cyclohexanone, cyclopentanone, dibutyl phthalate, dibutyl sebacate, diethyl carbonate, diethyl phthalate, dihydrolevoglucosenone, dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, 1,4-dioxane, 3-heptanone, hexamethylphosphoramide, 3-hexanone, methyl ethyl ketone, N-methyl-2-pyrrolidinone, 3-octanone, 3-pentanone, propylene carbonate, tetrahydrofuran, tetramethylurea, triacetin, triethyl citrate, triethyl phosphate, trimethyl phosphate, N,N'-tetrabutyl succinamide, and mixtures thereof.

10. An anode for an all-solid-state lithium-ion battery, the anode comprising an active material coated with the coating layer according to any one of claims 1 to 7.

11. wherein the active material is graphite, Li ４ Ti ５ O １２ type lithium titanate, titanium oxide TiO ２ , silicon or lithium / silicon alloy, tin oxide, lithium intermetallic compound, or a mixture thereof, the anode according to claim 10.

12. The anode according to claim 10, having a porosity of less than 10%, preferably less than 5%.

13. A method for manufacturing a Li-ion battery negative electrode, the method comprising the following operations: - providing an anode, - depositing the coating layer according to any one of claims 1 to 7 on the anode. The method comprising.

14. An all-solid-state Li-ion storage battery comprising a cathode, the anode according to claim 10, and an all-solid electrolyte.

15. The battery according to claim 14, wherein the cathode is coated with the coating layer according to any one of claims 1 to 7.