All-solid-state battery and method for manufacturing the same

Abstract

The present invention relates to an all-solid-state battery and a manufacturing method thereof. More specifically, the inside of an electrode adjacent to a sulfide-based solid electrolyte film is solvent-free or a non-polar solvent is contained in the electrode, thereby reducing the interfacial resistance between the sulfide-based solid electrolyte film and the electrode, thereby improving the performance of the all-solid-state battery.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2023-0106058 filed on August 14, 2023, and Korean Patent Application No. 10-2024-0104404 filed on August 6, 2024, and all contents disclosed in the documents of said Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to an all-solid-state battery and a method for manufacturing the same. [Background technology]

[0003] Currently, various batteries that can overcome the limitations of lithium secondary batteries are being researched from the viewpoints of battery capacity, safety, output, size increase, and miniaturization.

[0004] Representative examples of batteries that are being continuously researched in academia and industry include metal-air batteries, which have a much larger theoretical capacity than lithium secondary batteries, all-solid-state batteries, which are safe and do not pose a risk of explosion, supercapacitors, which have higher output, NaS batteries or RFBs (redox flow batteries), which are larger, and thin film batteries, which are smaller.

[0005] All-solid-state batteries are batteries that replace the liquid electrolyte used in conventional lithium secondary batteries with a solid electrolyte, and they can significantly improve safety by not using flammable solvents inside the battery and completely eliminating the risk of fire or explosion caused by the decomposition reaction of conventional electrolytes.In addition, because lithium metal or lithium alloys can be used as the anode material, they have the advantage of dramatically improving the energy density relative to the mass and volume of the battery.

[0006] Research is ongoing to commercialize all-solid-state batteries that use sulfide-based solid electrolytes, which have high ionic conductivity and ductility among solid electrolytes.

[0007] All-solid-state batteries containing a sulfide-based solid electrolyte are typically fabricated by inserting a sulfide-based solid electrolyte membrane between a positive electrode and a negative electrode and then subjecting the membrane to a high-pressure press. To fabricate an all-solid-state battery containing a positive electrode, a sulfide-based solid electrolyte membrane, and a negative electrode, a free-standing sulfide-based solid electrolyte membrane can be used, a sulfide-based solid electrolyte membrane can be transferred to an electrode, or a sulfide-based solid electrolyte can be overcoated onto an electrode. Overcoating an electrode with a sulfide-based solid electrolyte membrane is advantageous in that it increases process efficiency and enables the production of a thin solid electrolyte membrane.

[0008] However, when a sulfide-based solid electrolyte membrane is overcoated on an electrode, the solvent in the electrolyte slurry may penetrate into the electrode, squeezing small, light electrolyte particles and binders and positioning them at the interface between the electrode and the sulfide-based solid electrolyte membrane, which may increase the interfacial resistance.

[0009] Therefore, when a sulfide-based solid electrolyte membrane is overcoated on an electrode, there is an increasing need for a technology that can prevent the electrolyte slurry from being squeezed and the solvent contained in the electrolyte slurry from permeating into the electrode. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Registration No. 4046376 Summary of the Invention [Problem to be solved by the invention]

[0011] The present inventors have conducted extensive research to solve the above problems, and as a result, have found that in an all-solid-state battery including a cathode, a sulfide-based solid electrolyte film, and an anode, if the cathode or anode to be overcoated with the sulfide-based solid electrolyte film is pre-impregnated with a non-polar solvent and then dried to become solvent-free or to contain a residual non-polar solvent, the solvent of the sulfide-based solid electrolyte slurry used during overcoating can be prevented from being squeezed and infiltrated into the cathode or anode, thereby reducing the interfacial resistance between the electrode and the electrolyte and improving battery performance.

[0012] Therefore, an object of the present invention is to provide an all-solid-state battery in which the interfacial resistance between the positive electrode or negative electrode and the sulfide-based solid electrolyte film is reduced, thereby improving the performance of the battery.

[0013] Another object of the present invention is to provide a method for producing the all-solid-state battery.

[0014] Technical Solutions To achieve the above object, the present invention provides an all-solid-state battery including a positive electrode, a negative electrode, and a sulfide-based solid electrolyte film interposed therebetween, wherein the positive electrode active material layer or the negative electrode active material layer contained in the positive electrode or the negative electrode is solvent-free or contains a non-polar solvent, and the dielectric constant of the non-polar solvent is 10 or less.

[0015] In one embodiment of the present invention, the non-polar solvent may include at least one selected from the group consisting of toluene, xylene, anisole, benzene, hexane, heptane, nonane, decane, dibromomethane, dichloromethane, chloroform, butyrate, and acetate.

[0016] In one embodiment of the present invention, the non-polar solvent may be contained in an amount of 100 ppm to 2000 ppm.

[0017] In one embodiment of the present invention, the sulfide-based solid electrolyte membrane may include a sulfide-based solid electrolyte having an argyrodite structure.

[0018] In one embodiment of the present invention, the sulfide-based solid electrolyte is Li 7-x PS 6-x A x (wherein A is Cl, Br, I, Sn or a combination thereof, and x is 0≦x≦2).

[0019] In one embodiment of the present invention, the negative electrode active material layer may include lithium metal or a negative electrode coating layer.

[0020] The present invention also provides a method for manufacturing an all-solid-state battery, comprising: (a) impregnating a positive electrode active material layer or a negative electrode active material layer included in a positive electrode or a negative electrode with a non-polar solvent; (b) overcoating a sulfide-based solid electrolyte membrane-forming slurry on the positive electrode active material layer or the negative electrode active material layer obtained in step (a) to form a sulfide-based solid electrolyte membrane; and (c) drying the sulfide-based solid electrolyte membrane obtained in step (b), wherein the non-polar solvent has a dielectric constant of 10 or less.

[0021] In one embodiment of the present invention, the sulfide-based solid electrolyte membrane forming slurry may be prepared by mixing a sulfide-based solid electrolyte with a solvent.

[0022] In one embodiment of the present invention, the solvent is a non-polar solvent, and the dielectric constant of the non-polar solvent may be 10 or less.

[0023] In an embodiment of the present invention, the slurry may further include a binder.

[0024] In one embodiment of the present invention, the coating may be performed by bar coating, roll coating, gravure coating, doctor blade coating, slot die coating, slurry coating, or extrusion coating.

[0025] In one embodiment of the present invention, the drying in step (c) may be performed at 40 to 90°C. [Effects of the Invention]

[0026] According to the present invention, in an all-solid-state battery formed by overcoating a sulfide-based solid electrolyte film on a cathode or anode, the cathode or anode is solvent-free or contains a non-polar solvent, thereby preventing the solvent of the slurry used in overcoating the sulfide-based solid electrolyte film from squeezing into the cathode or anode. This prevents the fine particles of components contained in the slurry that are squeezed together with the solvent from being squeezed, thereby preventing the accumulation of the fine particles at the interface. Furthermore, because the fine particles do not accumulate at the interface between the cathode or anode and the sulfide-based solid electrolyte film, interfacial resistance is reduced, improving the performance of the all-solid-state battery. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a photograph showing the results of an experiment for selecting a solvent that does not cause a side reaction with a sulfide-based solid electrolyte in a test example of the present invention. [Figure 2]1 is a scanning electron microscope (SEM) photograph of the interface between a negative electrode-less coating layer and a sulfide-based solid electrolyte film in all-solid-state batteries manufactured in Example 1 and Comparative Example 1 of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0028] BEST MODE FOR CARRYING OUT THE INVENTION For example, methods such as compression bonding, coating, and vapor deposition may be used. In addition, the negative electrode of the present invention also includes a case where a thin lithium film is formed on the metal plate by initial charging after assembling a battery without a thin lithium film on the negative electrode current collector.

[0029] In one embodiment of the present invention, the positive electrode included in the all-solid-state battery may include a positive electrode active material layer, and the positive electrode active material layer may be formed on one surface of a positive electrode current collector.

[0030] The positive electrode active material layer includes a positive electrode active material, a conductive material, and a binder, and may further include a sulfide-based solid electrolyte.

[0031] The positive electrode active material is not particularly limited as long as it is a material capable of reversibly absorbing and releasing lithium ions. For example, lithium cobalt oxide (LiCoO), lithium nickel oxide (LiNiO), Li[Ni x Co y Mn z M v ]O2 (wherein M is any one or more elements selected from the group consisting of Al, Ga, and In; 0.3≦x<1.0, 0≦y, z≦0.5, 0≦v≦0.1, x+y+z+v=1), Li (Li a M b-a-b’ M' b’ )O 2-c A c(wherein 0≦a≦0.2, 0.6≦b≦1, 0≦b'≦0.2, 0≦c≦0.2; M includes Mn and one or more elements selected from the group consisting of Ni, Co, Fe, Cr, V, Cu, Zn, and Ti; M' is one or more elements selected from the group consisting of Al, Mg, and B, and A is one or more elements selected from the group consisting of P, F, S, and N), and other layered compounds and compounds substituted with one or more transition metals; 1+y Mn 2-y Lithium manganese oxides such as LiMnO4 (where y is 0 to 0.33), LiMnO3, LiMn2O3, and LiMnO2; lithium copper oxide (Li2CuO2); vanadium oxides such as LiV3O8, LiFe3O4, V2O5, and Cu2V2O7; and the chemical formula LiNi 1-y Ni-site lithium nickel oxide represented by MyO2 (where M=Co, Mn, Al, Cu, Fe, Mg, B, or Ga, and y is 0.01 to 0.3); chemical formula: LiMn 2-y M y Examples of suitable lithium manganese composite oxides include, but are not limited to, lithium manganese composite oxides represented by LiMnO2 (where M is Co, Ni, Fe, Cr, Zn, or Ta, and y is 0.01 to 0.1) or Li2Mn3MO8 (where M is Fe, Co, Ni, Cu, or Zn); LiMn2O4, in which part of the Li in the chemical formula is replaced with an alkaline earth metal ion; disulfide compounds; and Fe2(MoO4)3.

[0032] The positive electrode active material may be contained in an amount of 60 to 90% by weight based on the total weight of the positive electrode active material layer. Specifically, the content of the positive electrode active material may be 60%, 65% or more by weight, or 70% or more by weight, or may be 80%, 85% or less by weight, or 90% or less by weight. If the content of the positive electrode active material is less than 60% by weight, the battery performance may be reduced, and if it exceeds 90% by weight, the mass transfer resistance may be increased.

[0033] The binder is as described above for the negative electrode.

[0034] The conductive material is as described above for the negative electrode.

[0035] The specific type of material of the sulfide-based solid electrolyte may be the same as that described for the sulfide-based solid electrolyte contained in the sulfide-based solid electrolyte membrane. However, the content of the sulfide-based solid electrolyte in the positive electrode active material layer may be 5 wt % to 25 wt %, specifically, 5 wt % or more, 8 wt % or more, or 10 wt % or more, or 15 wt % or less, 20 wt % or less, or 25 wt % or less, taking into consideration the ion conductivity characteristics.

[0036] The positive electrode current collector supports the positive electrode active material layer and plays a role in transferring electrons between an external conductor and the positive electrode active material layer.

[0037] The positive electrode current collector is not particularly limited as long as it does not cause a chemical change in the all-solid-state battery and has high electronic conductivity. For example, the positive electrode current collector can be made of copper, stainless steel, aluminum, nickel, titanium, palladium, baked carbon, copper or stainless steel surface-treated with carbon, nickel, silver, or the like, or an aluminum-cadmium alloy.

[0038] The positive electrode current collector may have a micro-irregular structure on its surface or a three-dimensional porous structure to strengthen the bonding strength with the positive electrode active material layer, and may have various forms such as a film, sheet, foil, mesh, net, porous material, foam, or nonwoven fabric.

[0039] The positive electrode can be manufactured by a conventional method. Specifically, the positive electrode active material, conductive material, and binder are mixed in an organic solvent to form a positive electrode active material layer. The resulting composition is applied to a positive electrode current collector, dried, and optionally compressed into a current collector to improve electrode density. Preferably, the organic solvent is one that can uniformly disperse the positive electrode active material, binder, and conductive material and is easily evaporated. Specific examples of the organic solvent include acetonitrile, methanol, ethanol, tetrahydrofuran, water, and isopropyl alcohol.

[0040] Manufacturing method for all-solid-state batteries The present invention also relates to a method for manufacturing an all-solid-state battery.

[0041] Another method for manufacturing an all-solid-state battery according to the present invention includes the steps of: (a) impregnating a cathode active material layer or an anode active material layer contained in a cathode or an anode with a non-polar solvent; (b) overcoating a sulfide-based solid electrolyte membrane-forming slurry on the cathode active material layer or the anode active material layer obtained in step (a) to form a sulfide-based solid electrolyte membrane; and (c) drying the sulfide-based solid electrolyte membrane obtained in step (b). The non-polar solvent may have a dielectric constant of 1 to 10.

[0042] Hereinafter, each step of the method for manufacturing an all-solid-state battery according to the present invention will be described in more detail.

[0043] The types, properties, and weights of the materials contained in the positive electrode, negative electrode, and sulfide-based solid electrolyte membrane in the method for producing an all-solid-state battery are the same as those described above.

[0044] In one embodiment of the present invention, in step (a), a positive electrode active material layer or a negative electrode active material layer included in a positive electrode or a negative electrode may be impregnated with a non-polar solvent.

[0045] The positive electrode may be produced by applying a positive electrode active material layer forming slurry onto a positive electrode current collector and drying the slurry.

[0046] The negative electrode may be manufactured by coating a negative electrode active material layer-forming slurry on a negative electrode current collector and drying the coating. The negative electrode active material layer may be an anode-less coating layer that does not contain a negative electrode active material.

[0047] The method for impregnating the positive electrode active material layer or the negative electrode active material layer with the non-polar solvent is not particularly limited as long as it is a method that can spray the non-polar solvent to impregnate the positive electrode active material layer or the negative electrode active material layer. For example, an appropriate amount of the non-polar solvent can be sprayed onto the positive electrode active material layer or the negative electrode active material layer using a micropipette or a sprayer.

[0048] In one embodiment of the present invention, in step (b), a sulfide-based solid electrolyte membrane may be formed by overcoating a sulfide-based solid electrolyte membrane-forming slurry on the cathode active material layer or the anode active material layer obtained in step (a).

[0049] The sulfide-based solid electrolyte membrane-forming slurry is prepared by mixing sulfide-based solid electrolyte particles and a solvent, and the solvent may be a non-polar solvent having a dielectric constant of 1 to 10. The non-polar solvent may include at least one selected from the group consisting of butyrate, acetate, xylene, and anisole. The slurry may be prepared to have a solid content of 45% to 60% by weight.

[0050] In addition, when preparing the sulfide-based solid electrolyte membrane forming slurry, a binder may be added to improve binding strength and mechanical properties.

[0051] The coating method for forming the overcoat may be bar coating, roll coating, gravure coating, doctor blade coating, slot die coating, slurry coating, or extrusion coating, but is not limited thereto as long as it is a coating method commonly practiced in the art.

[0052] In one embodiment of the present invention, in step (c), the sulfide-based solid electrolyte membrane obtained in step (b) may be dried.

[0053] The drying may be carried out at a temperature of 40° C. to 90° C. Specifically, the drying temperature may be 40° C. or higher, 45° C. or higher, 50° C. or higher, 55° C. or higher, or 60° C. or higher, or 70° C. or lower, 75° C. or lower, 80° C. or lower, 85° C. or lower, or 90° C. or lower. If the drying temperature is lower than 40° C., the amount of residual solvent may be excessive, and if it exceeds 90° C., the high drying temperature may cause denaturation of the binder.

[0054] After the sulfide-based solid electrolyte film is formed on the positive electrode active material layer or the negative electrode active material layer in this manner, an all-solid-state battery can be manufactured by stacking a negative electrode or a positive electrode on the other side of the sulfide-based solid electrolyte film and applying pressure.

[0055] The pressure can be applied within a range that allows for good bonding between the positive electrode, sulfide-based solid electrolyte membrane, and negative electrode without causing deformation or damage to these. For example, the pressure during pressurization may be 300 MPa to 700 MPa, and more specifically, the pressure during pressurization may be 300 MPa or more, 350 MPa or more, or 400 MPa or more, or 600 MPa or less, 650 MPa or less, or 700 MPa or less. If the pressure during pressurization is less than 300 MPa, the interfacial resistance between the positive electrode or negative electrode and the sulfide-based solid electrolyte membrane may increase, while if it exceeds 700 MPa, the positive electrode, negative electrode, or sulfide-based solid electrolyte membrane may be deformed or damaged.

[0056] Battery module The present invention also relates to a battery module including the all-solid-state battery as a unit cell, a battery pack including the battery module, and a device including the battery pack as a power source.

[0057] Specific examples of the device include, but are not limited to, power tools powered by electric motors; electric vehicles including electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (PHEVs); electric two-wheeled vehicles including electric bicycles (E-bikes) and electric scooters; electric golf carts; and power storage systems.

[0058] Preferred examples will be described below to aid in understanding the present invention. However, the following examples are merely illustrative of the present invention, and it will be apparent to those skilled in the art that various changes and modifications are possible within the scope of the scope and technical idea of ​​the present invention. Naturally, such changes and modifications also fall within the scope of the appended claims.

[0059] [Table 1]

[0060] Test example: Selection of a solvent that does not cause side reactions with sulfide-based solid electrolytes An experiment was conducted to identify a solvent that would not cause a side reaction with the sulfide-based solid electrolyte, as a solvent for impregnating the sulfide-based solid electrolyte membrane and the adjacent electrode.

[0061] The sulfide-based solid electrolyte Li6PS5Cl was dispersed in a non-polar solvent, butyrate (BB), and a polar solvent, ethylene carbonate (EC), and the color change was observed. If there was no color change, there was no side reaction, and if there was a color change, it meant that a side reaction was occurring.

[0062] FIG. 1 is a photograph showing the results of an experiment to select a solvent that does not cause a side reaction with a sulfide-based solid electrolyte in a test example of the present invention.

[0063] Referring to Figure 1, it was confirmed that the sulfide-based solid electrolyte powder (circle 1) did not change color when dispersed in butyrate (BB), a non-polar solvent (circle 2), but did change color when dispersed in ethylene carbonate (EC), a polar solvent (circle 3).

[0064] This confirmed that butyrate (BB), a non-polar solvent, does not undergo side reactions with sulfide-based solid electrolytes, and is therefore a suitable solvent for impregnating electrodes adjacent to sulfide-based solid electrolyte membranes in all-solid-state batteries.

[0065] Example 1 (1) Anode manufacturing A slurry for forming an anode-less coating layer was prepared by mixing a conductive material, carbon black, and a binder, PVDF (polyvinylidene fluoride), with a solvent, NMP (N-Methyl-2-pyrrolidone). The conductive material and binder were used in a weight ratio of 90:10, and the slurry was prepared so that the solid content was 45 wt %.

[0066] The slurry for forming the anode-less coating layer was coated on one side of a stainless steel (SS) substrate and then vacuum dried at 100° C. for 10 hours to form an anode-less coating layer.

[0067] A non-polar solvent, butyrate (BB, dielectric constant: 5), was sprayed onto the anode-less coating layer using a micropipette to wet the anode-less coating layer, thereby impregnating the anode-less coating layer with the non-polar solvent.

[0068] (2) Formation of sulfide-based solid electrolyte membrane by overcoating A sulfide-based solid electrolyte slurry was prepared by mixing Li6PS5Cl, which has an argyrodite structure as a sulfide-based solid electrolyte, and acrylonitrile butadiene rubber (NBR) as a binder in a weight ratio of 90:10 with butyrate, a non-polar solvent, to a solid content of 50 wt%.

[0069] The sulfide-based solid electrolyte membrane-forming slurry was applied onto the negative electrode-less coating layer, overcoated with a bar coater, and then vacuum-dried at 70°C for 5 hours to form a sulfide-based solid electrolyte membrane.

[0070] (3) Manufacturing of all-solid-state batteries A positive electrode was laminated on the sulfide-based solid electrolyte film, and then pressurized at a pressure of 600 MPa to manufacture an all-solid-state battery. 0.8 Co 0.1 Mn 0.1 O2, NCM811), conductive material (carbon fiber), sulfide-based solid electrolyte (Li6PS5Cl), and binder (polytetrafluoroethylene, PTFE) were mixed in a weight ratio of 84:0.2:14.8:1, and the positive electrode active material layer containing the mixture was applied to an Al foil positive electrode current collector and rolled to produce a positive electrode. The content of non-polar solvent remaining in the negative electrode was 443 ppm.

[0071] Comparative Example 1 Except for not impregnating the negative electrode-less coating layer with a non-polar solvent, the same procedure as in Example 1 was carried out. The content of the non-polar solvent remaining in the negative electrode was 32 ppm.

[0072] Comparative Example 2 An all-solid-state battery was fabricated in the same manner as in Example 1, except that the anode-less coating layer was immersed in a polar solvent, ethylene carbonate (EC, dielectric constant 85), instead of a non-polar solvent, butyrate. Due to a side reaction between the polar solvent and the overcoated sulfide-based solid electrolyte membrane, it was impossible to evaluate the battery performance and measure the solvent content.

[0073] Comparative Example 3 An all-solid-state battery was manufactured in the same manner as in Example 1, except that the anode-less coating layer was prepared without being impregnated with a non-polar solvent, the sulfide-based solid electrolyte membrane-forming slurry was formed on a PET substrate, and then the anode-less coating layer and the sulfide-based solid electrolyte membrane were bonded together under pressure. This bonding performed a transfer process, so that the sulfide-based solid electrolyte membrane was formed on the anode-less coating layer. At this time, the anode-less coating layer was not exposed to the non-polar solvent. The residual non-polar solvent content was 7 ppm.

[0074] Experimental Example 1 The contents of the residual non-polar solvent contained in the negative electrodes of the all-solid-state batteries manufactured in the Examples and Comparative Examples were compared.

[0075] After manufacturing the all-solid-state battery, the content of non-polar solvent remaining in the anode-less coating layer of the anode was measured using Headspace GC / FID (Headspace Gas Chromatography with Flame Ionization Detection) analysis. The sample for this solvent measurement was prepared to include the cathode, anode, and the sulfide-based solid electrolyte film formed as an overcoat between them.

[0076] As shown in Table 1, Example 1 was measured to have a relatively large amount of residual non-polar solvent in the negative electrode compared to Comparative Examples 1 to 3.

[0077] In Comparative Example 1, the process of impregnating the anode-less coating layer with a non-polar solvent was not performed, but residual non-polar solvent was measured. This was due to the non-polar solvent used in preparing the slurry when forming the sulfide-based solid electrolyte membrane as an overcoat.

[0078] In addition, in Comparative Example 2, the anode-less coating layer was impregnated with a polar solvent instead of a non-polar solvent, and due to a side reaction between the polar solvent and the overcoated sulfide-based solid electrolyte membrane, it was impossible to evaluate the battery performance and measure the solvent content.

[0079] In Comparative Example 3, the anode-less coating layer was not impregnated with a non-polar solvent, and the anode-less coating layer and the sulfide-based solid electrolyte membrane were formed and then bonded together, and a small amount of residual non-polar solvent was measured. The small amount of residual non-polar solvent in the anode was the same as that contained in the sulfide-based solid electrolyte membrane.

[0080] Experimental Example 2 The interface between the negative electrode-less coating layer and the sulfide-based solid electrolyte film was observed for the all-solid-state batteries fabricated in Example 1 and Comparative Example 1. The interface was observed using a scanning electron microscope (SEM, JEOL, IT-800).

[0081] FIG. 2 is a SEM photograph of the interface between the negative electrode-less coating layer and the sulfide-based solid electrolyte film in the all-solid-state batteries manufactured in Example 1 of the present invention and Comparative Example 1.

[0082] 2, it can be seen that, compared to Example 1, Comparative Example 1 has a large number of particle agglomerates (30) at the interface between the anode-less coating layer (10) and the sulfide-based solid electrolyte membrane (20). These particle agglomerates are accumulated at the interface when components of the slurry are squeezed and attempt to penetrate into the anode-less coating layer during the process of overcoating the slurry during the formation of the sulfide-based solid electrolyte membrane. The components of the slurry accumulated at the interface may be mainly small and light electrolyte particles, binders, etc.

[0083] On the other hand, in Example 1, it is difficult to observe such fine particles at the interface. This is because the anode-less coating layer of Example 1 is impregnated with butyrate (BB), a non-polar solvent, which prevents the components of the slurry from being squeezed and penetrating into the anode-less coating layer.

[0084] Meanwhile, in Comparative Example 2, a polar solvent, ethylene carbonate (EC), was used instead of the non-polar solvent, butyrate (BB), used in Example 1. However, a side reaction occurred between the polar solvent, ethylene carbonate (EC), impregnated in the anode-less coating layer and the sulfide-based solid electrolyte membrane overcoated on the anode-less coating layer, resulting in decomposition, making it impossible to conduct an experiment to observe the interface.

[0085] Although the present invention has been described above using limited examples and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention pertains within the technical spirit of the present invention and the equivalent scope of the claims set forth below. [Explanation of symbols]

[0086] 10: Negative electrode-less coating layer 20: Sulfide electrolyte membrane 30: Fine particle mass

Claims

1. An all-solid-state battery including a positive electrode, a negative electrode, and a sulfide-based solid electrolyte membrane interposed therebetween, The positive electrode active material layer or the negative electrode active material layer included in the positive electrode or the negative electrode is solvent-free or contains a non-polar solvent; The non-polar solvent has a dielectric constant of 10 or less.

2. 2. The all-solid-state battery according to claim 1, wherein the non-polar solvent comprises at least one selected from the group consisting of toluene, xylene, anisole, benzene, hexane, heptane, nonane, decane, dibromomethane, dichloromethane, chloroform, butyrate, and acetate.

3. The all-solid-state battery according to claim 1 , wherein the non-polar solvent is contained in an amount of 100 ppm or more and 2000 ppm or less.

4. 2. The all-solid-state battery according to claim 1, wherein the sulfide-based solid electrolyte film includes a sulfide-based solid electrolyte having an argyrodite structure.

5. The sulfide-based solid electrolyte is Li ７－ｘ P.S. ６－ｘ A ｘ 2. The all-solid-state battery according to claim 1, wherein A is Cl, Br, I, Sn, or a combination thereof, and x is 0≦x≦2.

6. The all-solid-state battery according to any one of claims 1 to 5, wherein the negative electrode active material layer contains lithium metal or a negative electrode-less coating layer.

7. (a) impregnating a positive electrode active material layer or a negative electrode active material layer contained in a positive electrode or a negative electrode with a non-polar solvent; (b) forming a sulfide-based solid electrolyte membrane by overcoating a sulfide-based solid electrolyte membrane-forming slurry on the cathode active material layer or the anode active material layer obtained in step (a); and (c) drying the sulfide-based solid electrolyte membrane obtained in step (b); The method for manufacturing an all-solid-state battery, wherein the non-polar solvent has a dielectric constant of 10 or less.

8. The method for producing an all-solid-state battery according to claim 7 , wherein the sulfide-based solid electrolyte film-forming slurry is produced by mixing a sulfide-based solid electrolyte with a solvent.

9. the solvent is a non-polar solvent; The method for manufacturing an all-solid-state battery according to claim 8, wherein the non-polar solvent has a dielectric constant of 10 or less.

10. The method for manufacturing an all-solid-state battery according to claim 8 , wherein the slurry further contains a binder.

11. 8. The method for manufacturing an all-solid-state battery according to claim 7, wherein the overcoating is performed by bar coating, roll coating, gravure coating, doctor blade coating, slot die coating, slurry coating, or extrusion coating.

12. The method for producing an all-solid-state battery according to any one of claims 7 to 11, wherein the drying in step (c) is performed at a temperature of 40°C or higher and 90°C or lower.

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