Solid-state electrolyte slurry, electrode slurry, solid-state electrolyte sheet, electrode sheet, solid-state battery cell, battery device, and electric device

Abstract

A solid-state electrolyte slurry, an electrode slurry, a solid-state electrolyte sheet, an electrode sheet, a solid-state battery cell, a battery device, and an electric device. The solid-state electrolyte slurry comprises a sulfide solid-state electrolyte material, a solvent, and a binder dissolved in the solvent. The solvent is a non-polar solvent, a weakly polar solvent, or a mixed solvent of the two. The binder comprises a polyacrylate binder and a non-polar polyolefin binder. The solid-state electrolyte slurry has high dispersibility, high suspension, and good adhesion. When the solid-state electrolyte slurry is used in a solid-state battery cell, the solid-state battery cell can have high initial coulombic efficiency.

Description

Solid-state electrolyte slurry, electrode slurry, solid-state electrolyte sheet, electrode sheet, solid-state battery cell, battery device, and power utilization device TECHNICAL FIELD

[0001] The present disclosure relates to a solid-state electrolyte slurry, an electrode slurry, a solid-state electrolyte sheet, an electrode sheet, a solid-state battery cell, a battery device, and a power utilization device. BACKGROUND

[0002] The solid-state battery cell replaces the non-aqueous organic electrolyte with a solid-state electrolyte sheet. Since the solid-state electrolyte sheet cannot spontaneously infiltrate the electrode, the solid-state electrolyte material and the electrode active material are usually used together to improve the ion transport properties of the electrode. Sulfide solid-state electrolyte material is one of the ideal solid-state electrolyte materials at present, but it has poor oxidation resistance and reduction resistance, which leads to a small range of solvents and binders that can be selected, and also leads to poor dispersibility of the slurry containing it, which is prone to gel problems and sedimentation problems. SUMMARY

[0003] The present disclosure provides a solid-state electrolyte slurry, an electrode slurry, a solid-state electrolyte sheet, an electrode sheet, a solid-state battery cell, a battery device, and a power utilization device, which has high dispersibility, high suspensibility, and good adhesion, is used in a solid-state battery cell, and enables the solid-state battery cell to have high initial coulomb efficiency.

[0004] In a first aspect, the present disclosure provides a solid-state electrolyte slurry, the solid-state electrolyte slurry comprising a sulfide solid-state electrolyte material, a solvent, and a binder dissolved in the solvent, the solvent being a non-polar solvent, a weakly polar solvent, or a mixed solvent of the two, the binder comprising a polyacrylate-based binder and a non-polar polyolefin-based binder; the polyacrylate-based binder comprising a structural unit represented by Formula 1, R1 being selected from C2 to C10 alkyl, R2, R3, R4 being independently selected from H or C1 to C3 alkyl.

[0005] By having the binder simultaneously comprising a polyacrylate-based binder and a non-polar polyolefin-based binder, the slurry can have high dispersibility, high suspensibility, and good adhesion, and the slurry can improve the sedimentation problem and the gel problem, and the solid-state electrolyte sheet and the electrode sheet can have good adhesion. In addition, the polyacrylate-based binder and the non-polar polyolefin-based binder of the present disclosure do not react with the sulfide solid-state electrolyte material, and have little effect on the ionic conductivity of the sulfide solid-state electrolyte material. The solid-state electrolyte slurry of the present disclosure is used in a solid-state battery cell, and also enables the solid-state battery cell to have high initial coulomb efficiency.

[0006] In some embodiments, the non-polar polyolefin-based binder includes one or more of a homopolymer non-polar polyolefin-based binder selected from one of the following monomers, a copolymer non-polar polyolefin-based binder selected from two or more of the following monomers: ethylene, propylene, butylene, isobutylene, pentene, hexene, heptylene, octene, butadiene, pentadiene, isoprene, hexadiene, octadiene, 2,3-dimethyl-1,3-butadiene, 3-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene.

[0007] In some embodiments, the non-polar polyolefin-based binder includes one or more of polyethylene, polypropylene, polybutylene, polyisobutylene, polybutadiene, polyisoprene, ethylene-propylene copolymer, ethylene-butylene copolymer, ethylene-octene copolymer, ethylene-propylene-butylene copolymer, ethylene-propylene-octene copolymer, isoprene-butadiene copolymer, ethylene-isoprene copolymer, ethylene-hexadiene copolymer.

[0008] The type of non-polar polyolefin-based binder is within the above range, which can be well dissolved in the solvent and can make the slurry have good suspension stability.

[0009] In some embodiments, the mass ratio of the polyacrylate-based binder to the non-polar polyolefin-based binder is 50:50 to 95:5.

[0010] The mass ratio of the polyacrylate-based binder to the non-polar polyolefin-based binder is within the above range, which can make the slurry better have high dispersibility, high suspension, and good adhesion, and can make the solid-state battery cell have higher initial coulombic efficiency.

[0011] In some embodiments, the weight average molecular weight of the polyacrylate-based binder is 0.9 million to 2 million.

[0012] The weight average molecular weight of the polyacrylate-based binder is within the above range, which can be well dissolved in the solvent and can make the slurry have good dispersibility and adhesion.

[0013] In some embodiments, the weight average molecular weight of the non-polar polyolefin-based binder is 4.5 million to 8.5 million.

[0014] The weight average molecular weight of the non-polar polyolefin-based binder is within the above range, which can be well dissolved in the solvent and can make the slurry have good suspension stability.

[0015] In some embodiments, the solvent comprises one or more of toluene, xylene, mesitylene, chlorobenzene, o-dichlorobenzene, anisole, n-hexane, n-pentane, isopentane, n-heptane, n-octane, isooctane, n-decane, trichlorotrifluoroethane, dichloromethane, trichloromethane, 2-methylpentane, 2,2-dimethylpentane, 3-methylpentane, 2,3-dimethylpentane, 2-methylhexane, 2,2-dimethylhexane, 3-methylhexane, 2,3-dimethylhexane, 3-ethylhexane, cyclohexane, cycloheptane, methylcyclohexane, t-butylcyclohexane, tetrahydrofuran, cyclopentene, cyclohexene, 1-methylcyclohexene, 4-methylcyclohexene, 1-ethylcyclohexene, 1,4-dimethylcyclohexene, 2,4-dimethyl-3-pentanone, cyclohexanone, methylformamide, 1-hexene, 2-hexene, 1-heptene, 2-heptene, 1-octene, 2-octene, ethylene dichloride, petroleum ether, trifluoroacetic acid, butyl chloride, trichloroethylene, carbon tetrachloride, propyl ether, diethyl ether, butyl acetate, ethyl acetate.

[0016] In some embodiments, the solid-state electrolyte slurry further comprises one or more of a halide solid-state electrolyte material, an oxide solid-state electrolyte material.

[0017] In a second aspect, the present disclosure provides a solid-state electrolyte sheet, which is obtained by drying the solid-state electrolyte slurry of the first aspect.

[0018] In a third aspect, the present disclosure provides an electrode slurry, which is a positive electrode slurry, the positive electrode slurry comprising a positive electrode active material, a positive electrode conductive agent, and the solid-state electrolyte slurry of the first aspect.

[0019] Thereby, the sedimentation and gelation problems of the positive electrode slurry can be improved, the coating quality of the positive electrode slurry can be improved, the adhesion of the positive electrode sheet can be improved, the ionic conductivity of the positive electrode sheet can be improved, the impedance of the positive electrode sheet can be reduced, and the solid-state battery monomer can have a high initial coulombic efficiency.

[0020] In a fourth aspect, the present disclosure provides an electrode sheet, which comprises a positive electrode current collector and a positive electrode film layer on at least one surface of the positive electrode current collector, the positive electrode film layer being obtained by drying the electrode slurry of the third aspect.

[0021] In a fifth aspect, the present disclosure provides an electrode slurry, which is a negative electrode slurry, the negative electrode slurry comprising a negative electrode active material and the solid-state electrolyte slurry of the first aspect.

[0022] Thereby, the sedimentation and gelation problems of the negative electrode slurry can be improved, the coating quality of the negative electrode slurry can be improved, the adhesion of the negative electrode sheet can be improved, the ionic conductivity of the negative electrode sheet can be improved, the impedance of the negative electrode sheet can be reduced, and the solid-state battery monomer can have a high initial coulombic efficiency.

[0023] In some embodiments, the electrode slurry further comprises a negative conductive agent.

[0024] In a sixth aspect, the present disclosure provides an electrode sheet, comprising a negative current collector and a negative film layer on at least one surface of the negative current collector, the negative film layer being obtained by drying the electrode slurry of the fifth aspect.

[0025] In a seventh aspect, the present disclosure provides a solid-state battery cell, comprising a positive electrode sheet, a solid-state electrolyte sheet and a negative electrode sheet, the solid-state electrolyte sheet being between the positive electrode sheet and the negative electrode sheet, the positive electrode sheet comprising a positive current collector and a positive film layer on at least one surface of the positive current collector, the positive film layer being obtained by drying the electrode slurry of the third aspect; and / or, the solid-state electrolyte sheet being obtained by drying the solid-state electrolyte slurry of the first aspect.

[0026] In some embodiments, the negative electrode sheet comprises a negative current collector and a lithium-based metal layer on at least one surface of the negative current collector.

[0027] In some embodiments, the negative electrode sheet comprises a negative current collector and a negative film layer on at least one surface of the negative current collector, the negative film layer being obtained by drying the electrode slurry of the fifth aspect.

[0028] In an eighth aspect, the present disclosure provides a battery device, comprising a plurality of the solid-state battery cell of the seventh aspect.

[0029] In a ninth aspect, the present disclosure provides an electric device, comprising the solid-state battery cell of the seventh aspect or the battery device of the eighth aspect. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings needed to be used in the embodiments of the present disclosure will be briefly introduced as follows. Obviously, the drawings described below are only some of the embodiments of the present disclosure, and other drawings can also be obtained according to the drawings without creative labor for those skilled in the art.

[0031] FIG. 1 shows a schematic diagram of a solid-state battery cell according to some embodiments of the present disclosure.

[0032] FIG. 2 shows a schematic diagram of an electric device according to some embodiments of the present disclosure.

[0033] In the drawings, the drawings are not necessarily drawn according to the actual scale. DETAILED DESCRIPTION

[0034] Hereinafter, specific embodiments of the solid electrolyte slurry, the electrode slurry, the solid electrolyte sheet, the electrode sheet, the solid battery cell, the battery device, and the power using device of the present disclosure will be described in detail with appropriate reference to the accompanying drawings. However, there will be cases where unnecessary detailed description is omitted. For example, there will be cases where detailed description of matters known well, repeated description of substantially identical structures are omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided so that those skilled in the art can fully understand the present disclosure, and are not intended to limit the subject matter recited in the claims.

[0035] The "ranges" disclosed in the present disclosure are defined in the form of lower and upper limits, and a given range is defined by selecting one lower limit and one upper limit, and the selected lower limit and upper limit define the boundaries of the particular range. The ranges defined in this way can be inclusive or exclusive of the end values, and can be arbitrarily combined, i.e., any lower limit can be combined with any upper limit to form a range. For example, if the ranges 60-120 and 80-110 are listed for a particular parameter, it is understood that the ranges 60-110 and 80-120 are also contemplated. Furthermore, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4, and 5 are listed, then the following ranges are all contemplated: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In the present disclosure, unless otherwise specified, a numerical range "a-b" represents a shorthand manner of describing the arbitrary real number combinations between a and b, where a and b are both real numbers. For example, the numerical range "0-5" means that all the real numbers between "0-5" have been listed herein, and "0-5" is just a shorthand notation for these numerical combinations. In addition, when it is stated that a certain parameter is an integer ≥ 2, it is equivalent to disclose that the parameter is, for example, an integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, and the like.

[0036] Unless otherwise specified, all embodiments and optional embodiments of the present disclosure can be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of the present disclosure.

[0037] Unless otherwise specified, all technical features and optional technical features of the present disclosure can be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of the present disclosure.

[0038] If not otherwise specified, all steps of the present disclosure can be performed in sequence or randomly, preferably in sequence. For example, the method comprising steps (a) and (b) means that the method can comprise steps (a) and (b) in sequence, or steps (b) and (a) in sequence. For example, the method comprising step (c) means that step (c) can be added to the method in any sequence, for example, the method can comprise steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0039] If not otherwise specified, in the present disclosure, the terms "first", "second", etc. are used to distinguish different objects, rather than to describe a specific sequence or primary and secondary relationship.

[0040] In the present disclosure, the terms "a plurality of" and "a plurality of kinds" mean two or more.

[0041] In the description of the embodiments of the present disclosure, if not otherwise specified, a first feature "on" or "under" a second feature can mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "above", "over" and "on" the second feature can mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature. The first feature "under", "below" and "under" the second feature can mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is horizontally lower than the second feature.

[0042] Unless otherwise specified, the test temperature of each parameter mentioned in the present disclosure is 25℃.

[0043] The solid-state battery cell mentioned in the embodiments of the present disclosure is capable of realizing the function of charging and discharging independently, and can continue to be used by activating the active material through charging after discharging. The solid-state battery cell can be in the shape of a cylinder, a cuboid or other shapes, which are not limited in the embodiments of the present disclosure. As shown in FIG. 1, the solid-state battery cell 5 is a cuboid structure as an example.

[0044] The battery apparatus mentioned in the embodiments of the present disclosure can comprise one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly can comprise a plurality of solid-state battery cells connected in series, in parallel or in a mixed manner through a busbar component.

[0045] In some embodiments, the battery cell assembly is typically formed by arranging a plurality of solid-state battery cells.

[0046] As an example, the battery cell assembly can be a battery module, which is formed by arranging and fixing a plurality of solid-state battery cells into one independent module. As an example, the battery module can be formed by bundling a plurality of solid-state battery cells by a cable tie.

[0047] In some embodiments, the battery device can be a battery pack, which includes a case and one or more battery cell assemblies, and the battery cell assemblies are accommodated in the case.

[0048] As an example, the battery cell assembly can be a battery module, which can be accommodated in the case by fixing the battery module in the case.

[0049] As an example, the battery cell assembly can also be accommodated in the case by directly fixing a plurality of solid-state battery cells in the case.

[0050] As an example, the case can include a first case and a second case. The first case and the second case are buckled so that a closed space is formed inside the case to accommodate the battery cell assembly. Here, closed means covered or closed, which can be sealed or unsealed. The first case can be a top cover or a bottom plate.

[0051] As an example, the case can include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected with the frame so that a closed space is formed inside the case to accommodate the battery cell assembly.

[0052] In some embodiments, the case can be part of the chassis structure of a vehicle. For example, part of the case can be at least part of the floor of the vehicle, or part of the case can be at least part of the cross beam and the longitudinal beam of the vehicle.

[0053] The technical solutions described in the embodiments of the present disclosure are applicable to various electric devices using solid-state battery cells and battery devices, such as mobile devices (e.g., mobile phones, tablet computers, notebook computers, etc.), electric vehicles (e.g., pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc. The solid-state battery cells and the battery devices are used to store or provide electric energy.

[0054] FIG. 2 is a schematic diagram of an electric device as an example. The electric device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc.

[0055] Due to the particularity of the structure of the sulfide solid electrolyte material, the oxidation resistance and the reduction resistance are poor, so the solvent and the binder matched therewith need to be weakly polar or non-polar. In addition, the particle size of the sulfide solid electrolyte material is usually small, and the specific surface area is large, so the slurry containing the sulfide solid electrolyte material is prone to dispersion problems, such as slurry gel problems, sedimentation problems, etc.

[0056] At present, the traditional binders for lithium ion batteries, such as polyvinylidene fluoride (PVDF), styrene-butadiene rubber (SBR), sodium carboxymethyl cellulose (CMC), polyacrylic acid (PAA), etc., are not suitable for use in the slurry system containing the sulfide solid electrolyte material. The solid-state battery monomer usually adopts nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), SEBS (linear three-embedded copolymer with polystyrene as the terminal segment and ethylene-butene copolymer obtained by hydrogenation of polybutadiene as the middle elastic embedded segment) binder, but these binders cannot simultaneously improve the sedimentation problem and the gel problem of the slurry, and also cause serious loss of ionic conductivity and low first coulombic efficiency of the solid-state battery monomer.

[0057] Based on this, the present disclosure provides a solid electrolyte slurry with high dispersibility and high suspensibility for use in a solid-state battery monomer, which can enable the solid-state battery monomer to have high first coulombic efficiency.

[0058] The solid electrolyte slurry of the present disclosure comprises a sulfide solid electrolyte material, a solvent, and a binder dissolved in the solvent, the solvent is a non-polar solvent, a weakly polar solvent or a mixed solvent of the two, and the binder comprises a polyacrylate binder and a non-polar polyolefin binder.

[0059] The polyacrylate binder comprises a structural unit shown in Formula 1, R1 is selected from C2 to C10 alkyl, and R2, R3, R4 are each independently selected from H or C1 to C3 alkyl.

[0060] The R1 group in the molecular structure of the polyacrylate binder is selected from C2 to C10 alkyl, which is a non-polar group, has lipophilicity, and the ester group has weak polarity and hydrophilicity, so that the polyacrylate binder has a dispersing effect, and at the same time the ester group in its molecular structure can provide a strong bonding effect. Therefore, the polyacrylate binder has both dispersibility and high adhesion, but its long suspension stability in non-polar solvents and / or weakly polar solvents is poor, which leads to poor storage performance of the slurry.

[0061] The nonpolar polyolefin-based binder can be stably and uniformly dispersed in the nonpolar solvent and / or the weakly polar solvent for a long time, the molecular structure of which is a nonpolar segment, and the interaction with the sulfide solid electrolyte material particles is weak, thereby reducing the problem of sedimentation of the slurry caused by the formation of agglomerates of the sulfide solid electrolyte material particles, and having a good anti-settling effect, but the molecular structure does not contain a strong adhesive functional group.

[0062] By including both the polyacrylate-based binder and the nonpolar polyolefin-based binder in the binder, the slurry can have high dispersibility, high suspensibility, and good adhesiveness, the problems of sedimentation and gelation of the slurry can be improved, and the solid electrolyte sheet and the electrode sheet can have good adhesion. In addition, the polyacrylate-based binder and the nonpolar polyolefin-based binder of the present disclosure do not react with the sulfide solid electrolyte material and have little effect on the ionic conductivity of the sulfide solid electrolyte material. The solid electrolyte slurry of the present disclosure, when used in a solid-state battery cell, can also provide a high initial coulombic efficiency to the solid-state battery cell.

[0063] R1 is selected from C2 to C10 alkyl, and R1 can be a straight-chain alkyl group or a branched-chain alkyl group. For example, R1 can be ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, or decyl.

[0064] Alternatively, R1 can be selected from C3 to C8 alkyl.

[0065] R1 is within the above range, which can allow the polyacrylate-based binder to be well dissolved in the solvent and the slurry containing the polyacrylate-based binder to have good dispersibility and adhesiveness.

[0066] R2, R3, and R4 are each independently selected from H or C1 to C3 alkyl. Alternatively, R2, R3, and R4 are each independently selected from H or methyl. More alternatively, R2 is selected from methyl, and R3 and R4 are selected from H.

[0067] R2, R3, and R4 are within the above range, which can allow the polyacrylate-based binder to be well dissolved in the solvent and the slurry containing the polyacrylate-based binder to have good dispersibility and adhesiveness.

[0068] In some embodiments, the weight average molecular weight of the polyacrylate-based binder can be 0.9 million to 2 million, for example, 0.9 million, 1 million, 1.1 million, 1.2 million, 1.3 million, 1.4 million, 1.5 million, 1.6 million, 1.7 million, 1.8 million, 1.9 million, 2 million, or a range consisting of any of the above values.

[0069] The weight average molecular weight of the polyacrylate-based binder is within the above range, and the slurry can be well dissolved in the solvent and have good dispersibility and cohesiveness.

[0070] In some embodiments, the non-polar polyolefin-based binder can include one or more of a homopolymer non-polar polyolefin-based binder selected from one of the following monomers, a copolymer non-polar polyolefin-based binder selected from two or more of the following monomers: ethylene, propylene, butylene, isobutylene, pentene, hexene, heptylene, octene, butadiene, pentadiene, isoprene, hexadiene, octadiene, 2,3-dimethyl-1,3-butadiene, 3-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene.

[0071] In some embodiments, the non-polar polyolefin-based binder can include one or more of polyethylene, polypropylene, polybutylene, polyisobutylene, polybutadiene, polyisoprene, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-octene copolymer, ethylene-propylene-butene copolymer, ethylene-propylene-octene copolymer, isoprene-butadiene copolymer, ethylene-isoprene copolymer, ethylene-hexadiene copolymer.

[0072] The kind of the non-polar polyolefin-based binder is within the above range, and the slurry can be well dissolved in the solvent and have good suspension stability.

[0073] In some embodiments, the weight average molecular weight of the non-polar polyolefin-based binder can be 450,000-850,000, for example, can be 450,000, 480,000, 500,000, 520,000, 540,000, 560,000, 580,000, 600,000, 620,000, 640,000, 660,000, 680,000, 700,000, 720,000, 740,000, 760,000, 780,000, 800,000, 820,000, 850,000, or a range consisting of any of the above values.

[0074] The weight average molecular weight of the non-polar polyolefin-based binder is within the above range, and the slurry can be well dissolved in the solvent and have good suspension stability.

[0075] The weight average molecular weight of the polyacrylate-based binder, the non-polar polyolefin-based binder refers to the weight average molecular weight converted by standard polystyrene using gel permeation chromatography (GPC).

[0076] In some embodiments, the mass ratio of the polyacrylate-based binder to the non-polar polyolefin-based binder can be 50:50 to 95:5, for example, can be 50:50, 51:49, 52:48, 53:47, 54:46, 55:45, 56:44, 57:43, 58:42, 59:41, 60:40, 61:39, 62:38, 63:37, 64:36, 65:35, 66:34, 67:33, 68:32, 69:31, 70:30, 71:29, 72:28, 73:27, 74:26, 75:25, 76:24, 77:23, 78:22, 79:21, 80:20, 81:19, 82:18, 83:17, 84:16, 85:15, 86:14, 87:13, 88:12, 89:11, 90:10, 91:9, 92:8, 93:7, 94:6, 95:5, or a range consisting of any of the aforementioned values.

[0077] The mass ratio of the polyacrylate-based binder to the non-polar polyolefin-based binder in the above range can make the slurry better have high dispersibility, high suspensibility, and good adhesion, and can also make the solid-state battery cell have higher first coulomb efficiency.

[0078] Alternatively, the mass ratio of the polyacrylate-based binder to the non-polar polyolefin-based binder can be 50:50 to 90:10, 50:50 to 85:15, 50:50 to 80:20, 55:45 to 90:10, 55:45 to 85:15, 55:45 to 80:20, 60:40 to 90:10, 60:40 to 85:15, 60:40 to 80:20.

[0079] The solvent is a non-polar solvent, a weakly polar solvent, or a mixed solvent of the two, and in some embodiments, the solvent can include, but is not limited to, one or more of toluene, xylene, trimethylbenzene, chlorobenzene, o-dichlorobenzene, anisole, n-hexane, n-pentane, isopentane, n-heptane, n-octane, isooctane, n-decane, trichlorotrifluoroethane, dichloromethane, trichloromethane, 2-methylpentane, 2,2-dimethylpentane, 3-methylpentane, 2,3-dimethylpentane, 2-methylhexane, 2,2-dimethylhexane, 3-methylhexane, 2,3-dimethylhexane, 3-ethylhexane, cyclohexane, cycloheptane, methylcyclohexane, t-butylcyclohexane, tetrahydrofuran, cyclopentene, cyclohexene, 1-methylcyclohexene, 4-methylcyclohexene, 1-ethylcyclohexene, 1,4-dimethylcyclohexene, 2,4-dimethyl-3-pentanone, cyclohexanone, methylformamide, 1-hexene, 2-hexene, 1-heptene, 2-heptene, 1-octene, 2-octene, dichloroethylene, petroleum ether, trifluoroacetic acid, butyl chloride, trichloroethylene, carbon tetrachloride, propyl ether, diethyl ether, butyl acetate, ethyl acetate.

[0080] In some embodiments, the sulfide solid electrolyte material can include one or more of Li6PS5X, LGPS-like sulfide solid electrolyte material, multi-element sulfide solid electrolyte material, X including one or more elements of F, Cl, Br, and I.

[0081] Optionally, the LGPS-like sulfide solid electrolyte material can include Li 10±δ5 Ge 1-g G g P 2-q Q q S 12-w W w , 0 < δ5 < 1, 0 < g < 1, 0 < q < 2, 0 < w < 1, G including one or both of Si and Sn, Q including Sb, W including one or more elements of O, Se, Te, Cl, Br, I, and F.

[0082] Optionally, the multi-element sulfide solid electrolyte material can include one or more of Li2S-P2S5, Li2S-SiS2, Li2S-GeS2, (100-u-v)Li2S-uP2S5-vM m N n , 0 < u < 100, 0 < v < 100, 0 < u + v < 100, 0 < m < 4, 0 < n < 6, M including one or more elements of Li, B, Ge, Si, Sn, and Sb, N including one or more elements of S, Se, Te, O, Cl, Br, I, and F.

[0083] In some embodiments, the sulfide solid electrolyte material can include, by way of example, one or more of Li6PS5Cl, Li6PS5Br, Li 10 GeP2S 12 , Li3PS4, Li7P3S 11 .

[0084] In some embodiments, the average particle size of the sulfide solid electrolyte material can be 50 nm - 5 μm.

[0085] In some embodiments, the solid electrolyte slurry can further include one or more of halide solid electrolyte material, oxide solid electrolyte material.

[0086] In some embodiments, the halide solid electrolyte material can include one or more of Li3YCl6, Li3YBr6, Li3ErCl6, Li3InCl6, Li3InBr6.

[0087] In some embodiments, the oxide solid-state electrolyte material can include one or more of a perovskite structure oxide solid-state electrolyte material, a garnet structure oxide solid-state electrolyte material, an oxide solid-state electrolyte material having a NASICON structure, an oxide solid-state electrolyte material having a LISICON structure.

[0088] The embodiments of the present disclosure further provide a preparation method of a solid-state electrolyte slurry, which can prepare the solid-state electrolyte slurry provided by the present disclosure.

[0089] The preparation method of the solid-state electrolyte slurry includes the following steps: uniformly stirring a sulfide solid-state electrolyte material, a polyacrylate binder, and a non-polar polyolefin binder in a solvent to obtain a solid-state electrolyte slurry, wherein the solvent is a non-polar solvent, a weakly polar solvent, or a mixed solvent of the two.

[0090] The embodiments of the present disclosure further provide a solid-state electrolyte sheet, which is obtained by drying the solid-state electrolyte slurry provided by the present disclosure.

[0091] In some embodiments, the total mass content of the polyacrylate binder and the non-polar polyolefin binder in the solid-state electrolyte sheet can be 0.5%-10%, for example, can be 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, or a range consisting of any of the above values, based on the total mass of the solid-state electrolyte sheet being 100%.

[0092] In some embodiments, the thickness of the solid-state electrolyte sheet can be 10 μm-50 μm.

[0093] The embodiments of the present disclosure further provide an electrode slurry. The electrode slurry can be a positive electrode slurry or a negative electrode slurry.

[0094] In some embodiments, the electrode slurry is a positive electrode slurry, which can include a positive electrode active material, a positive electrode conductive agent, and the solid-state electrolyte slurry provided by the present disclosure.

[0095] In this way, the sedimentation problem and the gel problem of the positive electrode slurry can be improved, the coating quality of the positive electrode slurry can be improved, the adhesion of the positive electrode sheet can be improved, the ionic conductivity of the positive electrode sheet can be improved, the impedance of the positive electrode sheet can be reduced, and the solid-state battery monomer can have a high initial coulomb efficiency.

[0096] In some embodiments, the positive electrode active material can include one or more of a lithium transition metal oxide and a modified material thereof, a lithium-containing phosphate and a modified material thereof, lithium titanate, sulfur, selenium, and tellurium.

[0097] Optionally, examples of lithium transition metal oxides can include, but are not limited to, one or more of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide.

[0098] Optionally, examples of lithium-containing phosphates can include, but are not limited to, one or more of lithium iron phosphate, a composite of lithium iron phosphate and carbon, lithium manganese phosphate, a composite of lithium manganese phosphate and carbon, lithium manganese iron phosphate, a composite of lithium manganese iron phosphate and carbon.

[0099] In some embodiments, to further enhance the energy density of the solid-state battery cell, the cathode active material can include one or more of lithium transition metal oxides of the general formula Li a Ni b Co c M d O e A f 0.8≤a≤1.2, 0.5≤b<1, 0<c<1, 0<d<1, 1≤e≤2, 0≤f≤1, M can include one or more of Mn, Al, Zr, Zn, Cu, Cr, Mg, Fe, V, Ti, and B, and A can include one or more of N, F, S, and Cl.

[0100] As examples, the cathode active material can include, but is not limited to, one or more of LiCoO2, LiNiO2, LiMnO2, LiMn2O4, LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2(simplified as NCM333), LiNi 0.5 Co 0.2 Mn 0.3 O2(simplified as NCM523), LiNi 0.5 Co 0.25 Mn 0.25 O2(simplified as NCM211), LiNi 0.6 Co 0.2 Mn 0.2 O2(simplified as NCM622), LiNi 0.8 Co 0.1 Mn 0.1 O2(simplified as NCM811), LiNi 0.96 Co 0.02 Mn 0.02 O2(simplified as Ni96), LiNi 0.80 Co 0.15 Al 0.05 O2, LiFePO4, LiMnPO4, and their respective modified materials.

[0101] The solid-state battery cell will be accompanied by Li deintercalation and consumption during charging and discharging, and the molar content of Li is different when the solid-state battery cell is discharged to different states. In the enumeration of the positive electrode active material in the present disclosure, the molar content of Li is the initial state of the material, i.e., the state before feeding, and the positive electrode active material is applied to the solid-state battery cell. After charging and discharging cycles, the molar content of Li will change. In the enumeration of the positive electrode active material in the present disclosure, the molar content of O is only the theoretical state value, and the release of oxygen from the crystal lattice will cause the molar content of O to change, and the actual molar content of O will also appear to float.

[0102] The modified material of each of the above positive electrode active materials can be a doping modification and / or a surface coating modification of the positive electrode active material.

[0103] In some embodiments, the positive electrode conductive agent can include, but is not limited to, one or more of super-p, acetylene black, carbon black, ketjen black, carbon dots, carbon nanotubes, graphene, carbon nanofibers, and vapor grown carbon fiber (VGCF).

[0104] The present disclosure also provides a preparation method of a positive electrode slurry, which can prepare the positive electrode slurry of the present disclosure.

[0105] In some embodiments, the preparation method of the positive electrode slurry includes the following steps: uniformly stirring a sulfide solid-state electrolyte material, a polyacrylate binder, and a non-polar polyolefin binder in a solvent to obtain a solid-state electrolyte slurry, the solvent being a non-polar solvent, a weakly polar solvent, or a mixed solvent of the two; uniformly stirring a positive electrode active material and a positive electrode conductive agent in the solid-state electrolyte slurry to obtain a positive electrode slurry.

[0106] In other embodiments, the preparation method of the positive electrode slurry includes the following steps: uniformly stirring a positive electrode active material, a positive electrode conductive agent, a sulfide solid-state electrolyte material, a polyacrylate binder, and a non-polar polyolefin binder in a solvent to obtain a positive electrode slurry, the solvent being a non-polar solvent, a weakly polar solvent, or a mixed solvent of the two.

[0107] The present disclosure also provides a positive electrode sheet, which is obtained by drying the positive electrode slurry provided by the present disclosure.

[0108] In some embodiments, the electrode slurry is a negative electrode slurry, which can include a negative electrode active material and the solid-state electrolyte slurry provided by the present disclosure.

[0109] In this way, the sedimentation problem and the gel problem of the negative electrode slurry can be improved, the coating quality of the negative electrode slurry can be improved, the adhesion of the negative electrode sheet can be improved, the ionic conductivity of the negative electrode sheet can be improved, the impedance of the negative electrode sheet can be reduced, and the solid-state battery cell can have a high initial coulomb efficiency.

[0110] In some embodiments, the negative active material can include, but is not limited to, one or more of natural graphite, artificial graphite, meso-carbon microbead, soft carbon, hard carbon, silicon-based material, tin-based material, lithium titanate, metal oxide. Optionally, the silicon-based material can include, but is not limited to, one or more of elemental silicon, silicon oxide, silicon-carbon composite, silicon-nitrogen composite, silicon alloy material. Optionally, the tin-based material can include, but is not limited to, one or more of elemental tin, tin oxide, tin alloy material. Optionally, the metal oxide includes one or more of TiO2, MoO2, In2O3, Al2O3, Cu2O, VO2, Ga2O3, Sb2O5, Bi2O5.

[0111] In some embodiments, the negative electrode slurry can further include a negative conductive agent. Optionally, the negative conductive agent can include, but is not limited to, one or more of super-p carbon, conductive graphite, acetylene black, carbon black, ketjen black, carbon dot, carbon nanotube, graphene, carbon nanofiber, vapor grown carbon fiber (VGCF).

[0112] The embodiments of the present disclosure further provide a preparation method of a negative electrode slurry, which can prepare the negative electrode slurry of the present disclosure.

[0113] In some embodiments, the preparation method of the negative electrode slurry includes the following steps: uniformly stirring a sulfide solid-state electrolyte material, a polyacrylate binder, and a non-polar polyolefin binder in a solvent to obtain a solid-state electrolyte slurry, the solvent being a non-polar solvent, a weakly polar solvent, or a mixed solvent of the two; uniformly stirring a negative active material and an optional negative conductive agent in the solid-state electrolyte slurry to obtain a negative electrode slurry.

[0114] In other embodiments, the preparation method of the negative electrode slurry includes the following steps: uniformly stirring a negative active material, an optional negative conductive agent, a sulfide solid-state electrolyte material, a polyacrylate binder, and a non-polar polyolefin binder in a solvent to obtain a negative electrode slurry, the solvent being a non-polar solvent, a weakly polar solvent, or a mixed solvent of the two.

[0115] The embodiments of the present disclosure further provide a negative electrode sheet, which is obtained by drying the negative electrode slurry provided by the present disclosure.

[0116] The present disclosure further provides a solid-state battery monomer, which includes a positive electrode sheet, a solid-state electrolyte sheet, and a negative electrode sheet, the solid-state electrolyte sheet being located between the positive electrode sheet and the negative electrode sheet.

[0117] [Positive electrode sheet]

[0118] In some embodiments, the positive electrode sheet can include a positive electrode current collector and a positive electrode film layer on at least one surface of the positive electrode current collector, the positive electrode film layer including a positive electrode active material, a positive electrode conductive agent, a sulfide solid electrolyte material, a polyacrylate-based binder, and a non-polar polyolefin-based binder, the types of the positive electrode active material, the positive electrode conductive agent, the sulfide solid electrolyte material, the polyacrylate-based binder, and the non-polar polyolefin-based binder can be referred to the above, and will not be repeated here; or the positive electrode film layer is obtained by drying the positive electrode slurry provided by the present disclosure.

[0119] The positive electrode current collector has two surfaces opposite in the thickness direction of itself, and the positive electrode film layer is disposed on any one or both of the two opposite surfaces of the positive electrode current collector.

[0120] In some embodiments, the mass content of the sulfide solid electrolyte material in the positive electrode film layer can be 5%-25%, for example, can be 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, or a range consisting of any of the above values, based on 100% of the total mass of the positive electrode film layer.

[0121] In some embodiments, the total mass content of the polyacrylate-based binder and the non-polar polyolefin-based binder in the positive electrode film layer can be 0.5%-10%, for example, can be 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, or a range consisting of any of the above values, based on 100% of the total mass of the positive electrode film layer.

[0122] In some embodiments, the positive electrode current collector can adopt a metal foil or a composite current collector. As an example of the metal foil, an aluminum foil, a carbon-coated aluminum foil, or a stainless steel foil can be adopted. The composite current collector can include a polymer material base layer and a metal material layer formed on at least one surface of the polymer material base layer. As an example, the metal material can include, but is not limited to, one or more of aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, a titanium alloy, silver, and a silver alloy. As an example, the polymer material base layer can include, but is not limited to, one or more of polypropylene, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), and polyethylene.

[0123] [Positive electrode sheet]

[0124] In some embodiments, the negative electrode sheet can include a negative electrode current collector and a lithium-based metal layer on at least one surface of the negative electrode current collector. The negative electrode current collector has two opposite surfaces in the thickness direction of itself, and the lithium-based metal layer is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.

[0125] In some embodiments, the lithium-based metal layer can include lithium or a lithium alloy, and the mass fraction of lithium in the lithium alloy is greater than 90%.

[0126] Optionally, the other elements in the lithium alloy can include one or more of In, Mg, Al, Zn, Sn, Ag, Au, Ga, Pt, and Fe.

[0127] Optionally, the lithium alloy can include a Li-In alloy, a Li-Mg alloy, a Li-Al alloy, a Li-Zn alloy, a Li-Fe alloy, or the like.

[0128] In other embodiments, the negative electrode sheet can include a negative electrode current collector and a negative electrode film layer on at least one surface of the negative electrode current collector, the negative electrode film layer including a negative electrode active material and a negative electrode binder. The negative electrode current collector has two opposite surfaces in the thickness direction of itself, and the negative electrode film layer is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.

[0129] In some embodiments, the negative electrode active material can include, but is not limited to, one or more of natural graphite, artificial graphite, mesocarbon microbeads, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, and metal oxides. Optionally, the silicon-based materials can include, but are not limited to, one or more of elemental silicon, silicon oxides, silicon-carbon composite materials, silicon-nitrogen composites, and silicon alloy materials. Optionally, the tin-based materials can include, but are not limited to, one or more of elemental tin, tin oxides, and tin alloy materials. Optionally, the metal oxides include one or more of TiO2, MoO2, In2O3, Al2O3, Cu2O, VO2, Ga2O3, Sb2O5, and Bi2O5.

[0130] Optionally, the negative electrode binder can include one or more of methyl vinyl silicone rubber, nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), styrene butadiene rubber (SBR), thermoplastic styrene butadiene rubber (SBS), isoprene rubber, cis-butadiene rubber (BR), ethyl cellulose, fluororubber, and acrylate rubber.

[0131] Optionally, the negative electrode film layer can further include a negative electrode conductive agent. The negative electrode conductive agent can include, but is not limited to, one or more of super conductive carbon, conductive graphite, acetylene black, carbon black, ketjen black, carbon dots, carbon nanotubes, graphene, carbon nanofibers, and vapor grown carbon fiber (VGCF).

[0132] In yet some embodiments, the negative electrode sheet can include a negative electrode current collector and a negative electrode film layer on at least one surface of the negative electrode current collector, the negative electrode film layer including a negative electrode active material, a sulfide solid electrolyte material, a polyacrylate-based binder, and a non-polar polyolefin-based binder, the types of the negative electrode active material, the sulfide solid electrolyte material, the polyacrylate-based binder, and the non-polar polyolefin-based binder can refer to the above, and will not be repeated here; or, the negative electrode film layer is obtained by drying the negative electrode slurry provided by the present disclosure.

[0133] Optionally, the mass content of the sulfide solid electrolyte material in the negative electrode film layer can be 5%-25%, for example, can be 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, or a range consisting of any of the above values, based on 100% of the total mass of the negative electrode film layer.

[0134] Optionally, the total mass content of the polyacrylate-based binder and the non-polar polyolefin-based binder in the negative electrode film layer can be 0.5%-10%, for example, can be 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, or a range consisting of any of the above values, based on 100% of the total mass of the negative electrode film layer.

[0135] Optionally, the negative electrode film layer can further include a negative electrode conductive agent. The negative electrode conductive agent can include, but is not limited to, one or more of super conductive carbon, conductive graphite, acetylene black, carbon black, ketjen black, carbon dots, carbon nanotubes, graphene, carbon nanofibers, and vapor grown carbon fiber (VGCF).

[0136] In some embodiments, the negative electrode current collector can adopt a metal foil or a composite current collector. As an example of the metal foil, a copper foil, a nickel foil, a copper alloy foil, or a nickel alloy foil can be adopted. The composite current collector can include a polymer material base layer and a metal material layer formed on at least one surface of the polymer material base layer. As an example, the metal material can include, but is not limited to, one or more of copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy. As an example, the polymer material base layer can include, but is not limited to, one or more of polypropylene, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene, and polyethylene.

[0137] [Solid electrolyte sheet]

[0138] In some embodiments, the solid-state electrolyte sheet comprises a solid-state electrolyte material. Optionally, the solid-state electrolyte material can comprise one or more of a sulfide solid-state electrolyte material, a halide solid-state electrolyte material, and an oxide solid-state electrolyte material. The types of the sulfide solid-state electrolyte material, the halide solid-state electrolyte material, and the oxide solid-state electrolyte material can refer to the above, and will not be repeated here.

[0139] Optionally, the solid-state electrolyte sheet can further comprise a binder. The binder can comprise one or more of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, styrene butadiene rubber (SBR), water-soluble unsaturated resin SR-1B, methyl vinyl silicone rubber, nitrile butadiene rubber (NBR), hydrogenated nitrile butadiene rubber (HNBR), thermoplastic styrene butadiene rubber (SBS), isoprene rubber, butadiene rubber (BR), ethyl cellulose, fluoro rubber, and acrylate rubber.

[0140] In other embodiments, the solid-state electrolyte sheet can comprise a sulfide solid-state electrolyte material, a polyacrylate-based binder, and a non-polar polyolefin-based binder. The types of the sulfide solid-state electrolyte material, the polyacrylate-based binder, and the non-polar polyolefin-based binder can refer to the above, and will not be repeated here. Alternatively, the solid-state electrolyte sheet can be obtained by drying the solid-state electrolyte slurry provided by the present disclosure.

[0141] In some embodiments, the total mass content of the polyacrylate-based binder and the non-polar polyolefin-based binder in the solid-state electrolyte sheet can be 0.5%-10%, for example, can be 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, or a range consisting of any of the above values, based on the total mass of the solid-state electrolyte sheet being 100%.

[0142] In some embodiments, the thickness of the solid-state electrolyte sheet can be 10 μm-50 μm.

[0143] In some embodiments, the solid-state battery cell can further comprise an outer package for accommodating the positive electrode sheet, the solid-state electrolyte sheet, and the negative electrode sheet. The outer package can be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc. The outer package can also be a soft package, such as a pouch-type soft package. The material of the soft package can be plastic, such as one or more of aluminum-plastic film, polypropylene, polybutylene terephthalate (PBT), and polybutylene succinate (PBS).

[0144] The preparation method of the solid-state battery cell is known. In some embodiments, a positive electrode sheet, a solid-state electrolyte sheet, and a negative electrode sheet can be assembled to obtain an electrode assembly, and the electrode assembly can be placed in an outer package to obtain a solid-state battery cell.

[0145] Embodiments

[0146] The following examples describe the present disclosure in more detail, which are only used for illustrative explanation, and various modifications and changes within the scope of the present disclosure are obvious to those skilled in the art. Unless otherwise stated, all parts, percentages and ratios reported in the following examples are based on mass, and all reagents used in the examples are commercially available or synthesized according to conventional methods, and can be used directly without further treatment, and the instruments used in the examples are commercially available.

[0147] Positive electrode slurry D1#

[0148] The positive electrode active material LiNi 0.8 Co 0.1 Mn 0.1 O2, the sulfide solid-state electrolyte material Li6PS5Cl, the positive electrode conductive agent vapor-grown carbon fiber (VGCF), and the positive electrode binder butyl nitrile rubber were weighed and mixed according to a solid mass ratio of 80:16:2:2, and then stirred uniformly in a weakly polar solvent dimethylbenzene to prepare the positive electrode slurry D1#.

[0149] Positive electrode slurry D2#

[0150] The positive electrode active material LiNi 0.8 Co 0.1 Mn 0.1 O2, the sulfide solid-state electrolyte material Li6PS5Cl, the positive electrode conductive agent vapor-grown carbon fiber (VGCF), and the positive electrode binder polypropyl methacrylate were weighed and mixed according to a solid mass ratio of 80:16:2:2, and then stirred uniformly in a weakly polar solvent dimethylbenzene to prepare the positive electrode slurry D2#. The weight average molecular weight of the positive electrode binder polypropyl methacrylate is between 1 million and 1.1 million.

[0151] Positive electrode slurry D3#

[0152] The positive electrode active material LiNi 0.8 Co 0.1 Mn 0.1 O2, the sulfide solid-state electrolyte material Li6PS5Cl, the positive electrode conductive agent vapor-grown carbon fiber (VGCF), and the positive electrode binder polypropylene were weighed and mixed according to a solid mass ratio of 80:16:2:2, and then stirred uniformly in a weakly polar solvent dimethylbenzene to prepare the positive electrode slurry D3#. The weight average molecular weight of the positive electrode binder polypropylene is between 0.5 million and 0.6 million.

[0153] Positive electrode slurry 1

[0154] The positive electrode active material LiNi 0.8 Co 0.1 Mn 0.1 O2, sulfide solid electrolyte material Li6PS5Cl, positive electrode conductive agent vapor grown carbon fiber (VGCF), positive electrode binder polypropyl methacrylate, and positive electrode binder polypropylene were weighed and mixed according to a solid mass ratio of 80:16:2:1.6:0.4, and then stirred uniformly in a weakly polar solvent dimethylbenzene to prepare a positive electrode slurry 1#. The weight average molecular weight of the positive electrode binder polypropyl methacrylate was between 1 million and 1.01 million, and the weight average molecular weight of the positive electrode binder polypropylene was between 0.5 million and 0.51 million.

[0155] Positive electrode slurry 2

[0156] The positive electrode active material LiNi 0.8 Co 0.1 Mn 0.1 O2, sulfide solid electrolyte material Li6PS5Cl, positive electrode conductive agent vapor grown carbon fiber (VGCF), positive electrode binder polypropyl methacrylate, and positive electrode binder polypropylene were weighed and mixed according to a solid mass ratio of 80:16:2:1.2:0.8, and then stirred uniformly in a weakly polar solvent dimethylbenzene to prepare a positive electrode slurry 2#. The weight average molecular weight of the positive electrode binder polypropyl methacrylate was between 1 million and 1.01 million, and the weight average molecular weight of the positive electrode binder polypropylene was between 0.5 million and 0.51 million.

[0157] Positive electrode slurry 3

[0158] The positive electrode active material LiNi 0.8 Co 0.1 Mn 0.1 O2, sulfide solid electrolyte material Li6PS5Cl, positive electrode conductive agent vapor grown carbon fiber (VGCF), positive electrode binder polypropyl methacrylate, and positive electrode binder polypropylene were weighed and mixed according to a solid mass ratio of 80:16:2:1:1, and then stirred uniformly in a weakly polar solvent dimethylbenzene to prepare a positive electrode slurry 3#. The weight average molecular weight of the positive electrode binder polypropyl methacrylate was between 1 million and 1.01 million, and the weight average molecular weight of the positive electrode binder polypropylene was between 0.5 million and 0.51 million.

[0159] Positive electrode slurry 4

[0160] The positive electrode active material LiNi 0.8 Co 0.1 Mn 0.1O2, sulfide solid-state electrolyte material Li6PS5Cl, positive electrode conductive agent vapor-grown carbon fiber (VGCF), positive electrode binder polypropyl methacrylate, and positive electrode binder polypropylene are weighed and mixed according to a solid mass ratio of 80:16:2:1.8:0.2, and then stirred uniformly in a weakly polar solvent dimethylbenzene to prepare a positive electrode slurry 4#. The weight average molecular weight of the positive electrode binder polypropyl methacrylate is between 1 million and 1.01 million, and the weight average molecular weight of the positive electrode binder polypropylene is between 0.5 million and 0.51 million.

[0161] Performance test of positive electrode slurry

[0162] The positive electrode slurry is placed in a beaker and allowed to stand at 25°C. After 24 hours, the slurry is poured out with the beaker, and whether the slurry can flow continuously is observed. If the slurry cannot flow continuously, it is considered to be gelled.

[0163] The positive electrode slurry is placed in a beaker and allowed to stand at 25°C. After 24 hours, the slurry is scraped with a spatula, and then the spatula is vertically scraped to allow the slurry on the spatula to flow naturally. If there is residual slurry in the form of a lump on the spatula, the slurry is considered to have settled. Otherwise, the slurry is considered to have no settlement.

[0164] Table 1

[0165] According to the test results above, the positive electrode slurry of the present disclosure has no settlement and no gelation for 24 hours, and can meet the requirements of industrial production line coating.

[0166] Solid-state battery monomer D1#

[0167] The positive electrode slurry D1# is coated on both sides of an aluminum foil, dried, and cut to obtain a positive electrode sheet D1#.

[0168] A negative electrode active material silicon-carbon composite material and a negative electrode binder styrene-butadiene rubber are weighed and mixed according to a solid mass ratio of 90:10, and then added to a solvent N-methylpyrrolidone to prepare a negative electrode slurry. The negative electrode slurry is then coated on both sides of a copper foil, dried, and a negative electrode sheet is obtained. A sulfide solid-state electrolyte material Li6PS5Cl and a styrene-butadiene rubber are weighed and mixed according to a solid mass ratio of 90:10, and then added to a weakly polar solvent dimethylbenzene to prepare a solid-state electrolyte slurry. The solid-state electrolyte slurry is then coated on the surface of the negative electrode film layer prepared above, dried, and cut to obtain a negative electrode sheet with a solid-state electrolyte sheet.

[0169] The negative electrode sheet-solid-state electrolyte sheet-positive electrode sheet are sequentially placed in order, and then heat-pressed and packaged in an outer packaging aluminum plastic film to obtain a solid-state battery monomer D1#.

[0170] Solid-state battery monomer D2#

[0171] The positive electrode slurry D2# is coated on both sides of the aluminum foil, dried, cut, and then a positive electrode sheet D2# is obtained.

[0172] The negative electrode active material silicon-carbon composite material and the negative electrode binder styrene-butadiene rubber are mixed according to a solid mass ratio of 90:10, added into a solvent N-methyl pyrrolidone, and then a negative electrode slurry is prepared. The negative electrode slurry is coated on both sides of the copper foil, dried, and then a negative electrode sheet is obtained. The sulfide solid electrolyte material Li6PS5Cl and the styrene-butadiene rubber are mixed according to a solid mass ratio of 90:10, added into a weakly polar solvent dimethylbenzene, and then a solid electrolyte slurry is prepared. The solid electrolyte slurry is coated on the surface of the negative electrode film layer prepared above, dried, cut, and then a negative electrode sheet with a solid electrolyte sheet is obtained.

[0173] The negative electrode sheet, the positive electrode sheet, and the negative electrode sheet are sequentially placed in the order of negative electrode sheet-positive electrode sheet-negative electrode sheet, and then encapsulated in an outer packaging aluminum plastic film after hot pressing treatment, and a solid-state battery monomer D2# is obtained.

[0174] Solid-state battery monomer D3#

[0175] The positive electrode slurry D3# is coated on both sides of the aluminum foil, dried, cut, and then a positive electrode sheet D3# is obtained.

[0176] The negative electrode active material silicon-carbon composite material and the negative electrode binder styrene-butadiene rubber are mixed according to a solid mass ratio of 90:10, added into a solvent N-methyl pyrrolidone, and then a negative electrode slurry is prepared. The negative electrode slurry is coated on both sides of the copper foil, dried, and then a negative electrode sheet is obtained. The sulfide solid electrolyte material Li6PS5Cl and the styrene-butadiene rubber are mixed according to a solid mass ratio of 90:10, added into a weakly polar solvent dimethylbenzene, and then a solid electrolyte slurry is prepared. The solid electrolyte slurry is coated on the surface of the negative electrode film layer prepared above, dried, cut, and then a negative electrode sheet with a solid electrolyte sheet is obtained.

[0177] The negative electrode sheet, the positive electrode sheet, and the negative electrode sheet are sequentially placed in the order of negative electrode sheet-positive electrode sheet-negative electrode sheet, and then encapsulated in an outer packaging aluminum plastic film after hot pressing treatment, and a solid-state battery monomer D3# is obtained.

[0178] Solid-state battery monomer 1#

[0179] The positive electrode slurry 1# is coated on both sides of the aluminum foil, dried, cut, and then a positive electrode sheet 1# is obtained.

[0180] The negative electrode active material silicon-carbon composite material and the negative electrode binder styrene-butadiene rubber are mixed according to a solid mass ratio of 90:10, added into a solvent N-methyl pyrrolidone, and then a negative electrode slurry is prepared; then the negative electrode slurry is coated on both surfaces of a copper foil, dried, and a negative electrode sheet is obtained; the sulfide solid electrolyte material Li6PS5Cl and the styrene-butadiene rubber are mixed according to a solid mass ratio of 90:10, added into a weakly polar solvent dimethylbenzene, and then a solid electrolyte slurry is prepared; then the solid electrolyte slurry is coated on the surface of the negative electrode film layer prepared above, dried, cut, and a negative electrode sheet with a solid electrolyte sheet is obtained.

[0181] The negative electrode sheet, the positive electrode sheet and the negative electrode sheet are sequentially placed in the order of negative electrode sheet-positive electrode sheet-negative electrode sheet, and then packaged in an outer packaging aluminum plastic film after hot pressing treatment, and a solid-state battery monomer 1# is obtained.

[0182] Solid-state battery monomer 2#

[0183] The positive electrode slurry 2# is coated on both surfaces of an aluminum foil, dried, and cut, and a positive electrode sheet 2# is obtained.

[0184] The negative electrode active material silicon-carbon composite material and the negative electrode binder styrene-butadiene rubber are mixed according to a solid mass ratio of 90:10, added into a solvent N-methyl pyrrolidone, and then a negative electrode slurry is prepared; then the negative electrode slurry is coated on both surfaces of a copper foil, dried, and a negative electrode sheet is obtained; the sulfide solid electrolyte material Li6PS5Cl and the styrene-butadiene rubber are mixed according to a solid mass ratio of 90:10, added into a weakly polar solvent dimethylbenzene, and then a solid electrolyte slurry is prepared; then the solid electrolyte slurry is coated on the surface of the negative electrode film layer prepared above, dried, cut, and a negative electrode sheet with a solid electrolyte sheet is obtained.

[0185] The negative electrode sheet, the positive electrode sheet and the negative electrode sheet are sequentially placed in the order of negative electrode sheet-positive electrode sheet-negative electrode sheet, and then packaged in an outer packaging aluminum plastic film after hot pressing treatment, and a solid-state battery monomer 2# is obtained.

[0186] Solid-state battery monomer 3#

[0187] The positive electrode slurry 3# is coated on both surfaces of an aluminum foil, dried, and cut, and a positive electrode sheet 3# is obtained.

[0188] The negative electrode active material silicon-carbon composite material and the negative electrode binder styrene-butadiene rubber are mixed according to a solid mass ratio of 90:10, added into a solvent N-methyl pyrrolidone, and then a negative electrode slurry is prepared; then the negative electrode slurry is coated on both surfaces of a copper foil, dried, and a negative electrode sheet is obtained; the sulfide solid electrolyte material Li6PS5Cl and the styrene-butadiene rubber are mixed according to a solid mass ratio of 90:10, added into a weakly polar solvent dimethylbenzene, and then a solid electrolyte slurry is prepared; then the solid electrolyte slurry is coated on the surface of the negative electrode film layer prepared above, dried, cut, and a negative electrode sheet with a solid electrolyte sheet is obtained.

[0189] The positive electrode sheet, the negative electrode sheet and the positive electrode sheet are sequentially stacked and placed in order of negative electrode sheet-positive electrode sheet-negative electrode sheet, and after hot pressing treatment, they are placed in an outer packaging aluminum plastic film for packaging to obtain a solid-state battery monomer 3#.

[0190] Solid-state battery monomer 4#

[0191] The positive electrode slurry 4# is coated on both sides of the aluminum foil, dried and cut to obtain a positive electrode sheet 4#.

[0192] The negative electrode active material silicon-carbon composite material and the negative electrode binder styrene-butadiene rubber are weighed and mixed in a solid mass ratio of 90:10 and added to a solvent N-methyl pyrrolidone to prepare a negative electrode slurry, and then the negative electrode slurry is coated on both sides of the copper foil and dried to obtain a negative electrode sheet; the sulfide solid-state electrolyte material Li6PS5Cl and the styrene-butadiene rubber are weighed and mixed in a solid mass ratio of 90:10 and added to a weakly polar solvent dimethylbenzene to prepare a solid-state electrolyte slurry, and then the solid-state electrolyte slurry is coated on the surface of the negative electrode film layer prepared above, dried and cut to obtain a negative electrode sheet with a solid-state electrolyte sheet.

[0193] The positive electrode sheet, the negative electrode sheet and the positive electrode sheet are sequentially stacked and placed in order of negative electrode sheet-positive electrode sheet-negative electrode sheet, and after hot pressing treatment, they are placed in an outer packaging aluminum plastic film for packaging to obtain a solid-state battery monomer 4#.

[0194] Performance test

[0195] (1) Impedance and ionic conductivity test of positive electrode sheet

[0196] 100 mg of positive electrode powder is scraped from the surface of the prepared positive electrode sheet and placed in a sleeve, and 4000 Kg of pressure is applied to press the positive electrode film sheet, and the thickness is measured and recorded as L; 60 mg of sulfide solid-state electrolyte material Li6PS5Cl is loaded into the two sides of the sleeve, and 2000 Kg of pressure is applied to each side to press the sheet; 60 mg of indium powder is loaded into the two sides of the sleeve, and 2000 Kg of pressure is applied to each side to press the sheet; and lithium-coated copper sheets are loaded into the two sides of the sleeve to assemble a symmetrical battery, and 4000 Kg of pressure is applied to the symmetrical battery for 5 min; the alternating current impedance value R of the positive electrode sheet is obtained by using the alternating current impedance spectrum (EIS) on the electrochemical workstation, the test temperature is 25℃, the test frequency range is 10 5 -10 -2 Hz, and the bias voltage is 10 mV.

[0197] The ionic conductivity of the positive electrode sheet is calculated according to the following formula: σ=L / (R*S). L is the thickness of the positive electrode film sheet, R is the alternating current impedance value in the alternating current impedance spectrum, and S is the area of the positive electrode film sheet.

[0198] (2) First coulomb efficiency test of solid-state battery monomer

[0199] The test temperature was 25°C, and the solid-state battery cell was tested under a pressure of 15 MPa.

[0200] The solid-state battery cell was charged at a rate of 0.1C to a voltage of 4.3 V (vs. Li + / Li) at this time, and the charge specific capacity was recorded as the first cycle charge specific capacity; then, the cell was rested for 5 min, and then discharged at a rate of 0.1C to a voltage of 2 V (vs. Li + / Li), and the discharge specific capacity was recorded as the first cycle discharge specific capacity.

[0201] The first cycle coulombic efficiency of the solid-state battery cell (%) = the first cycle discharge specific capacity / the first cycle charge specific capacity x 100%.

[0202] Table 2

[0203] From the above test results, it can be seen that the positive electrode slurry of the present disclosure has good coating quality, and the positive electrode sheet prepared from the positive electrode slurry has low impedance and high ionic conductivity.

[0204] From the above test results, it can be seen that the positive electrode sheet prepared from the positive electrode slurry of the present disclosure can make the solid-state battery cell have high first cycle coulombic efficiency.

[0205] It should be noted that the present disclosure is not limited to the above embodiments. The above embodiments are only examples, and embodiments having substantially the same configuration and playing the same role and effect within the scope of the technical solutions of the present disclosure are all included within the technical scope of the present disclosure. In addition, within the scope of the main idea of the present disclosure, various modifications that can be thought of by those skilled in the art are applied to the embodiments, and other modes constructed by combining part of the constituent elements in the embodiments are also included within the scope of the present disclosure.

Claims

1. A solid-state electrolyte slurry, characterized by, The solid-state electrolyte slurry comprises a sulfide solid-state electrolyte material, a solvent, and a binder dissolved in the solvent, the solvent is a non-polar solvent, a weakly polar solvent, or a mixed solvent of the two, the binder comprises a polyacrylate-based binder and a non-polar polyolefin-based binder; The polyacrylate-based adhesive includes a structural unit represented by Formula 1, R1 is selected from C2 to C10 alkyl, R2, R3, R4 are independently selected from H or C1 to C3 alkyl.

2. The solid-state electrolyte slurry of claim 1, wherein, The non-polar polyolefin-based binder comprises one or more of a homopolymer non-polar polyolefin-based binder selected from one of the following monomers, a copolymer non-polar polyolefin-based binder selected from two or more of the following monomers: ethylene, propylene, butylene, isobutylene, pentene, hexene, heptyl, octene, butadiene, pentadiene, isoprene, hexadiene, octadiene, 2,3-dimethyl-1,3-butadiene, 3-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene.

3. The solid-state electrolyte slurry of claim 2, wherein, The non-polar polyolefin-based binder comprises one or more of polyethylene, polypropylene, polybutylene, polyisobutylene, polybutadiene, polyisoprene, ethylene-propylene copolymer, ethylene-butylene copolymer, ethylene-octene copolymer, ethylene-propylene-butylene copolymer, ethylene-propylene-octene copolymer, isoprene-butadiene copolymer, ethylene-isoprene copolymer, ethylene-hexadiene copolymer.

4. The solid-state electrolyte slurry of any one of claims 1-3, wherein, The mass ratio of the polyacrylate-based binder to the non-polar polyolefin-based binder is 50:50 to 95:

5.

5. The solid-state electrolyte slurry of any one of claims 1-4, wherein, The weight average molecular weight of the polyacrylate-based binder is 0.9 million to 2 million; and / or, The weight average molecular weight of the non-polar polyolefin-based binder is 0.45 million to 0.85 million.

6. The solid-state electrolyte slurry of any one of claims 1-5, wherein, The solvent comprises one or more of toluene, xylene, trimethylbenzene, chlorobenzene, o-dichlorobenzene, anisole, n-hexane, n-pentane, isopentane, n-heptane, n-octane, isooctane, n-decane, trichlorotrifluoroethane, dichloromethane, trichloromethane, 2-methylpentane, 2,2-dimethylpentane, 3-methylpentane, 2,3-dimethylpentane, 2-methylhexane, 2,2-dimethylhexane, 3-methylhexane, 2,3-dimethylhexane, 3-ethylhexane, cyclohexane, cycloheptane, methylcyclohexane, tert-butylcyclohexane, tetrahydrofuran, cyclopentene, cyclohexene, 1-methylcyclohexene, 4-methylcyclohexene, 1-ethylcyclohexene, 1,4-dimethylcyclohexene, 2,4-dimethyl-3-pentanone, cyclohexanone, methylformamide, 1-hexene, 2-hexene, 1-heptene, 2-heptene, 1-octene, 2-octene, dichloroethylene, petroleum ether, trifluoroacetic acid, butyl chloride, trichloroethylene, carbon tetrachloride, propyl ether, diethyl ether, butyl acetate, ethyl acetate.

7. The solid-state electrolyte slurry of any one of claims 1-6, wherein, The solid-state electrolyte slurry further comprises one or more of a halide solid-state electrolyte material, an oxide solid-state electrolyte material.

8. A solid-state electrolyte sheet, characterized by, The solid-state electrolyte sheet is obtained by drying the solid-state electrolyte slurry of any one of claims 1-7.

9. An electrode slurry, characterized by, The electrode slurry is a positive electrode slurry, the positive electrode slurry comprising a positive active material, a positive conductive agent, and the solid-state electrolyte slurry of any one of claims 1-7.

10. An electrode sheet characterized by The electrode sheet comprises a positive current collector and a positive film layer on at least one surface of the positive current collector, the positive film layer being obtained by drying the electrode slurry of claim 9.

11. An electrode slurry, characterized by, The electrode slurry is a negative electrode slurry, the negative electrode slurry comprising a negative active material, and the solid-state electrolyte slurry of any one of claims 1-7.

12. The electrode paste of claim 11, wherein, The electrode slurry further comprises a negative conductive agent.

13. An electrode tab, characterized by The electrode sheet comprises a negative current collector and a negative film layer on at least one surface of the negative current collector, the negative film layer being obtained by drying the electrode slurry of any one of claims 11-12.

14. A solid-state battery cell comprising a positive electrode sheet, a solid-state electrolyte sheet, and a negative electrode sheet, the solid-state electrolyte sheet being located between the positive electrode sheet and the negative electrode sheet, characterized by, The positive electrode sheet comprises a positive current collector and a positive film layer on at least one surface of the positive current collector, the positive film layer being obtained by drying the electrode slurry of claim 9; and / or, the solid-state electrolyte sheet is obtained by drying the solid-state electrolyte slurry of any one of claims 1-7.

15. The solid state battery cell of claim 14, wherein, The negative electrode sheet comprises a negative current collector and a lithium-based metal layer on at least one surface of the negative current collector.

16. The solid state battery cell of claim 14, wherein, The negative electrode sheet comprises a negative current collector and a negative film layer on at least one surface of the negative current collector, the negative film layer being obtained by drying the electrode slurry of any one of claims 11-12.

17. A battery device characterized by comprising: The solid-state battery device comprises a plurality of solid-state battery cells of any one of claims 14-16.

18. An electrical device, comprising: The solid-state battery device comprises the solid-state battery cell of any one of claims 14-16 or the battery device of claim 17.

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