All-solid-state battery and method for manufacturing same

Abstract

Provided are an all-solid-state battery and a manufacturing method therefor, wherein the all-solid-state comprises: a positive electrode including a positive electrode active material layer; a negative electrode including a negative electrode current collector, a negative electrode coating layer on the negative electrode current collector, and a sulfur coating layer on the negative electrode coating layer; and a solid electrolyte layer disposed between the positive electrode active material layer and the sulfur coating layer, wherein the negative electrode coating layer includes a metal carbon composite, and the sulfur coating layer includes sulfur-based materials.

Description

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

[0001] This is about all-solid-state batteries.

[0002] Recently, driven by industrial demands, the development of batteries with high energy density and safety is actively underway. For example, lithium batteries are being put into practical use not only in information and communication equipment sectors but also in the automotive sector. In the automotive field, safety is considered particularly important because it is directly related to human life.

[0003] Since lithium batteries use an electrolyte containing a flammable organic solvent, there is a possibility of overheating and fire if a short circuit occurs.

[0004] All-solid-state batteries using a solid electrolyte instead of a liquid electrolyte are being proposed.

[0005] By not using flammable organic solvents, all-solid-state batteries can significantly reduce the likelihood of fire or explosion in the event of a short circuit. These batteries can greatly enhance safety compared to lithium batteries that use liquid electrolytes.

[0006] Secondary batteries use sulfur-based materials as cathode active materials to increase capacity. Using sulfur-based materials allows for a higher theoretical energy capacity compared to lithium-ion batteries, and the low cost of sulfur-based materials can lower the manufacturing cost of secondary batteries.

[0007] One aspect is to provide all-solid-state batteries with improved lifespan characteristics.

[0008] Another aspect is to provide a method for manufacturing an all-solid-state battery with improved lifespan characteristics.

[0009] According to one embodiment, an all-solid-state battery is provided comprising: a positive electrode including a positive active material layer; a negative electrode including a negative current collector, a negative coating layer on the negative current collector, and a sulfur coating layer on the negative coating layer; and a solid electrolyte layer disposed between the positive active material layer and the sulfur coating layer, wherein the negative coating layer comprises a metal carbon composite and the sulfur coating layer comprises sulfur-based materials.

[0010] According to another embodiment, an all-solid-state battery is provided, comprising: a positive electrode including a positive active material layer; a negative electrode including a negative current collector and a negative coating layer on the negative current collector; a solid electrolyte layer disposed between the positive electrode and the negative electrode; and a protective layer disposed between the negative coating layer and the solid electrolyte layer, wherein the protective layer comprises a metal carbon composite, sulfur-based materials, and a solid electrolyte.

[0011] According to another embodiment, a method for manufacturing an all-solid-state battery is provided, comprising: providing a positive electrode; providing a negative electrode comprising a negative current collector and a negative coating layer on the negative current collector; providing a solid electrolyte layer between the positive electrode and the negative electrode; and forming a sulfur coating layer between the negative electrode and the solid electrolyte layer.

[0012] According to one aspect, an all-solid-state battery comprising a sulfur coating layer or a protective layer can provide an all-solid-state battery with improved lifespan characteristics.

[0013] FIG. 1 is a cross-sectional view of an all-solid-state battery according to an exemplary embodiment.

[0014] FIG. 2 is a cross-sectional view of an all-solid-state battery according to an exemplary embodiment.

[0015] FIG. 3 is a cross-sectional view of an all-solid-state battery according to an exemplary embodiment.

[0016] FIG. 4 is a cross-sectional view of an all-solid-state battery according to an exemplary embodiment.

[0017] FIG. 5 is a cross-sectional view of an all-solid-state battery according to an exemplary embodiment.

[0018] FIG. 6 is a cross-sectional view of an all-solid-state battery according to another exemplary embodiment.

[0019] FIG. 7 is a cross-sectional view of an all-solid-state battery according to another exemplary embodiment.

[0020] The present inventive concept described below is subject to various modifications and may have various embodiments, and specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present inventive concept to specific embodiments and should be understood to include all modifications, equivalents, or substitutions that fall within the scope of the description of the present inventive concept.

[0021] The terms used below are used merely to describe specific embodiments and are not intended to limit the creative concept. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the following, terms such as “comprising” or “having” are intended to indicate the existence of the features, numbers, steps, actions, components, parts, components, materials, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, components, materials, or combinations thereof. The “ / ” used below may be interpreted as “and” or “or” depending on the context.

[0022] In the drawings, thicknesses have been enlarged or reduced to clearly represent various layers and regions. Throughout the specification, the same reference numerals have been used for similar parts. Throughout the specification, when a part such as a layer, film, region, or plate is described as being “on” or “above” another part, this includes not only cases where it is directly above another part but also cases where there is another part in between. Throughout the specification, terms such as “first,” “second,” etc., may be used to describe various components, but the components should not be limited by these terms. In this specification and drawings, components having substantially the same functional configuration are referred to by the same reference numerals to avoid redundant descriptions.

[0023] In the present disclosure, the “size” of a particle is, for example, the “particle diameter” of the particle. The “particle diameter” of the particle represents the average diameter when the particle is spherical and represents the average major axis length when the particle is non-spherical. The particle diameter of the particle can be measured using a particle size analyzer (PSA). The “particle diameter” of the particle is, for example, the average particle diameter. The average particle diameter is, for example, the median particle diameter (D50). The median particle diameter (D50) is the particle size corresponding to the 50% cumulative volume calculated from the side of the particle having a small particle size in the particle size distribution measured, for example by laser diffraction.

[0024] In the present disclosure, “metal” includes both metals and metalloids such as silicon and germanium in an elemental or ionic state.

[0025] In this disclosure, “alloy” means a mixture of two or more metals.

[0026] In the present disclosure, “anode active material” refers to an anode material capable of undergoing lithiation and delithiation.

[0027] In the present disclosure, “anode active material” refers to an anode material capable of undergoing lithiation and delithiation.

[0028] In the present disclosure, “lithiation” and “to lithiate” refer to the process of adding lithium to a positive electrode active material or a negative electrode active material.

[0029] In the present disclosure, “delithiation” and “to delithiate” refer to the process of removing lithium from a positive electrode active material or a negative electrode active material.

[0030] In this disclosure, “charge” and “to charge” refer to the process of providing electrochemical energy to a battery.

[0031] In this disclosure, “anode” and “cathode” refer to electrodes where electrochemical reduction and lithiation occur during the discharge process.

[0032] In this disclosure, “cathode” and “anode” refer to electrodes where electrochemical oxidation and delithiation occur during the discharge process.

[0033] A solid-state battery and a method for manufacturing the same according to exemplary embodiments are described in more detail below.

[0034] Hereinafter, with reference to FIGS. 1 to 5, an all-solid-state battery according to one embodiment will be described.

[0035] Referring to FIG. 1, an all-solid-state battery according to one embodiment comprises: a positive electrode (100) comprising a positive active material layer (120); a negative electrode (200) comprising a negative current collector (210), a negative coating layer (220) on the negative current collector (210), and a sulfur coating layer (230) on the negative coating layer (220); and a solid electrolyte layer (300) disposed between the positive active material layer (120) and the sulfur coating layer (230); wherein the negative coating layer (220) comprises a metal carbon composite, and the sulfur coating layer (230) may comprise sulfur-based materials. By including a sulfur coating layer (230) on the negative electrode (200) on the negative electrode coating layer (220), side reactions of the solid electrolyte between the negative electrode coating layer (220) and the solid electrolyte layer (300) are suppressed, thereby improving the cycle characteristics of the all-solid-state battery. By including a sulfur-based material in the sulfur coating layer (230), electrochemical stability is improved, and thereby the interfacial stability of the negative electrode coating layer (220) adjacent to the solid electrolyte layer (300) can be improved.

[0036] Referring to FIG. 1, the all-solid-state battery may include a positive electrode (100) comprising a positive electrode active material layer (120); a negative electrode (200) comprising a negative electrode current collector (210), a negative electrode coating layer (220) on the negative electrode current collector (210), and a sulfur coating layer (230) on the negative electrode coating layer (220); and a solid electrolyte layer (300) disposed between the positive electrode active material layer (120) and the sulfur coating layer (230).

[0037] (cathode)

[0038] Referring to FIG. 1, the cathode (200) may include a cathode current collector (210), a cathode coating layer (220) on the cathode current collector (210), and a sulfur coating layer (230) on the cathode coating layer (220).

[0039] The negative current collector (210) may provide a reference surface on which the negative coating layer (220) is disposed. The negative current collector (210) may include, for example, a material that does not react with lithium, that is, does not form any alloys or compounds with lithium. The material constituting the negative current collector (210) may include at least one metal selected from the group consisting of, for example, copper (Cu), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), and nickel (Ni). The thickness of the negative current collector may be 1 to 20 μm, for example 5 to 15 μm, for example 7 to 10 μm.

[0040] The negative current collector (210) may be composed of one of the metals described above, or may include an alloy of two or more metals or a coating material. The negative current collector (210) is, for example, in the form of a plate or foil. The negative current collector (210) may be omitted.

[0041] Although not shown in the drawing, the negative current collector (210) may include, for example, a base film and a metal layer disposed on one or both sides of the base film. The base film may include, for example, a polymer. The polymer may be, for example, a thermoplastic polymer. The polymer may include, for example, polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polybutylene terephthalate (PBT), polyimide (PI), or a combination thereof. The polymer may be an insulating polymer. By including an insulating thermoplastic polymer in the base film, the base film may soften or liquefy upon the occurrence of a short circuit, thereby blocking battery operation and suppressing a sudden increase in current. The metal layer may include, for example, copper (Cu), stainless steel (SUS), titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), or an alloy thereof. The negative current collector (210) may additionally include a metal piece and / or a lead tab. By having the negative electrode current collector (210) have this structure, the weight of the negative electrode can be reduced and, as a result, the energy density of the negative electrode and the lithium secondary battery can be improved.

[0042] The negative electrode coating layer (220) can be configured to allow lithium metal to grow between it and the negative electrode current collector (210) during charging of the all-solid-state battery. The negative electrode coating layer (220) can serve as a protective layer for the lithium metal and simultaneously suppress the precipitation and growth of lithium dendrites. The negative electrode coating layer (220) may include, for example, a metal carbon composite and a binder.

[0043] The metal-carbon composite comprising the cathode coating layer (220) is a cathode material capable of forming an alloy or compound with, for example, lithium. The metal-carbon composite has, for example, a particle form. The average particle size of the metal-carbon composite having a particle form is, for example, 4 μm or less, 3 μm or less, 2 μm or less, 1 μm or less, or 900 nm or less. The average particle size of the metal-carbon composite having a particle form is, for example, 10 nm to 4 μm, 10 nm to 3 μm, 10 nm to 2 μm, 10 nm to 1 μm, or 10 nm to 900 nm. By having the average particle size of the metal-carbon composite within this range, reversible absorption and / or desorption of lithium during charging and discharging may be more easily facilitated. Since the metal-carbon composite has an average particle size within this range, the reversible plating of lithium during charging and discharging can be made easier. The average particle size of the metal-carbon composite is, for example, the median diameter (D50) measured using a laser particle size distribution meter.

[0044] Metal-carbon composites may include, for example, metal particles and carbon-based materials.

[0045] The metal particles and carbon-based materials within the metal-carbon composite can each have a particle form, for example.

[0046] Metal-carbon composites can be, for example, a simple mixture of metal particles and carbon-based materials.

[0047] The metal-carbon composite may, for example, have a form in which metal particles are supported on a carbon-based material. Localization of the metal particles within the cathode coating layer (220) is prevented, and a uniform distribution can be obtained.

[0048] For example, metal-carbon composites can be composites of metal particles and carbon-based materials.

[0049] The metal particles within the metal-carbon composite may include, for example, gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), zinc (Zn), or combinations thereof. However, this is not limited thereto, and any metal or metalloid used to form an alloy or compound with lithium in the relevant technical field is acceptable.

[0050] The carbonaceous material in the metal-carbon composite may include, for example, amorphous carbon, crystalline carbon, porous carbon, or a combination thereof. The carbonaceous material in the metal-carbon composite may be, for example, amorphous carbon. The carbonaceous material in the metal-carbon composite may include, for example, carbon black, acetylene black, furnace black, Kettjen black, graphene, or a combination thereof. Amorphous carbon may be carbon that does not have crystallinity or has very low crystallinity.

[0051] The carbonaceous material within the metal-carbon composite may be, for example, porous carbon. The pore volume contained in the porous carbon may be, for example, 0.1 cc / g to 10.0 cc / g, 0.5 cc / g to 5 cc / g, or 0.1 cc / g to 1 cc / g. The average pore diameter contained in the porous carbon may be, for example, 1 nm to 50 nm, 1 nm to 30 nm, or 1 nm to 10 nm. The BET specific surface area of ​​the porous carbon is, for example, 100 m² 2 / g to 3,000 m 2 It can be / g. The BET specific surface area of ​​porous carbon can be measured, for example, according to ISO 9277:2022.

[0052] The mixing ratio of metal particles and carbon-based material included in the cathode coating layer (220) may be, for example, 10:1 to 1:2, 5:1 to 1:1, or 4:1 to 2:1 by weight. By having such a composition of the cathode coating layer (220), the cycle characteristics of the all-solid-state battery may be improved.

[0053] The cathode coating layer (220) may further include a binder. The binder may be, for example, styrene-butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, vinylidene fluoride / hexafluoropropylene copolymer, polyacrylonitrile, polymethyl methacrylate, etc., but is not necessarily limited to these, and any binder used in the art may be used. The binder may be composed of a single binder or a plurality of different binders.

[0054] The cathode coating layer (220) is stabilized on the cathode current collector (210) by including a binder. Additionally, cracking of the cathode coating layer (220) is suppressed despite volume changes and / or relative position changes of the cathode coating layer (220) during the charging and discharging process. For example, if the cathode coating layer (220) does not include a binder, it is possible for the cathode coating layer (220) to be easily separated from the cathode current collector (210). As the cathode coating layer (220) detaches from the cathode current collector (210), the possibility of a short circuit occurring increases in the portion of the cathode current collector (210) exposed by the cathode current collector (210) coming into contact with the solid electrolyte layer (300). The cathode coating layer (220) is produced, for example, by applying a slurry in which the material constituting the cathode coating layer (220) is dispersed onto a cathode current collector (210) and drying it. By including a binder in the cathode coating layer (220), stable dispersion of the metal-carbon composite in the slurry is possible. For example, when the slurry is applied onto the cathode current collector (210) by a screen printing method, it is possible to suppress clogging of the screen.

[0055] The cathode coating layer (220) may further include other additives in addition to the metal-carbon composite. The cathode coating layer (220) may further include at least one additive selected from the group consisting of, for example, fillers, coating agents, dispersants, and ion-conducting aids.

[0056] The thickness of the negative electrode coating layer (220) may be, for example, 50% or less, 40% or less, 30% or less, 20% or less, 10% or less, or 5% or less of the thickness of the positive electrode active material layer (120). The thickness of the negative electrode coating layer (220) may be, for example, 1 µm to 20 µm, 2 µm to 10 µm, or 3 µm to 7 µm. If the thickness of the negative electrode coating layer (220) is excessively thin, lithium dendrites formed between the negative electrode coating layer (220) and the negative electrode current collector (210) may cause the negative electrode coating layer (220) to collapse, making it difficult to improve the cycle characteristics of the all-solid-state battery. If the thickness of the negative electrode coating layer (220) increases excessively, the energy density of the all-solid-state battery decreases, and the internal resistance of the all-solid-state battery due to the negative electrode coating layer (220) increases, making it difficult to improve the cycle characteristics of the all-solid-state battery.

[0057] The sulfur coating layer (230) may be formed to cover at least a portion of one side of the negative electrode coating layer (220). The sulfur coating layer (230) may be formed to cover the entire side of one side of the negative electrode coating layer (220). By including electrochemically stable sulfur-based materials, the sulfur coating layer (230) can suppress side reactions occurring between the negative electrode coating layer (220) and the solid electrolyte layer (300) during charging and discharging of the all-solid-state battery. By including sulfur-based materials with excellent physical properties, the sulfur coating layer (230) can suppress the excessive growth of lithium dendrites. An all-solid-state battery including such a sulfur coating layer (230) can have improved lifespan characteristics. The sulfur coating layer (230) may include sulfur-based materials.

[0058] Sulfur-based materials may be compounds containing sulfur atoms. In one embodiment, sulfur-based materials may have a chemical structure centered on a sulfur atom. Sulfur-based materials can play an important role in improving battery performance and ensuring stability.

[0059] Sulfur-based materials may include, for example, S (Sulfur), S8 (Octasulfur), H2S, Li3PO4, LiCl, Li2S, SO2, SO3, or a combination thereof. By including such sulfur-based materials in the sulfur coating layer (230), side reactions occurring between the cathode coating layer (220) and the solid electrolyte layer (300) can be suppressed.

[0060] Sulfur-based materials may include S (Sulfur), S8 (Octasulfur), Li2S8, Li2S6, Li2S4, Li2S2, Li2S, or a combination thereof. By including such sulfur-based materials in the sulfur coating layer (230), the interfacial resistance between the cathode coating layer (220) and the solid electrolyte layer (300) can be reduced.

[0061] The thickness of the sulfur coating layer (230) may be, for example, 30% or more of the thickness of the cathode coating layer (220). The thickness of the sulfur coating layer (230) may be, for example, 35% or more, 40% or more, 45% or more, or 50% or more of the thickness of the cathode coating layer (220). The thickness of the sulfur coating layer (230) may be, for example, 150% or less of the thickness of the cathode coating layer (220). The thickness of the sulfur coating layer (230) may be, for example, 150% or less, 145% or less, 140% or less, 135% or less, or 130% or less of the thickness of the cathode coating layer (220). The thickness of the sulfur coating layer (230) may be, for example, 1.5㎛ to 7.5㎛, 2㎛ to 7㎛, or 2.5㎛ to 6.5㎛. If the thickness of the sulfur coating layer (230) is excessively thin, the effect of suppressing side reactions occurring between the cathode coating layer (220) and the solid electrolyte layer (300) may be minimal. If the thickness of the sulfur coating layer (230) is excessively thick, the interfacial resistance between the cathode coating layer (220) and the solid electrolyte layer (300) may increase.

[0062] The content of sulfur atoms (S) included in the sulfur coating layer (230) may be 30 at% to 100 at% with respect to the total atomic content included in the sulfur coating layer (230). For example, the content of sulfur atoms (S) included in the sulfur coating layer (230) may be 40 at% to 100 at%, 45 at% to 100 at%, or 50 at% to 100 at% with respect to the total atomic content included in the sulfur coating layer (230). For example, the content of sulfur atoms (S) included in the sulfur coating layer (230) may be 30 at% to 99 at%, 40 at% to 99 at%, or 50 at% to 99 at% with respect to the total atomic content included in the sulfur coating layer (230). The content of sulfur atoms (S) in the sulfur coating layer (230) can be measured, for example, through X-ray photoelectron analysis (XPS), second ion mass spectrometry (SIMS), energy dispersive X-ray spectroscopy (EDS / EDX), plasma spectroscopy (ICP-OES), or mass spectrometry (ICP-MS), but is not necessarily limited thereto.

[0063] Referring to FIG. 2, the all-solid-state battery may further include a lithium metal layer (240) disposed between, for example, a negative electrode current collector (210) and a solid electrolyte layer (300) by charging. The all-solid-state battery may further include a lithium metal layer (240) disposed between, for example, a negative electrode current collector (210) and a negative electrode coating layer (220) by charging. Although not shown in the drawing, the all-solid-state battery may further include a lithium metal layer disposed between, for example, a solid electrolyte layer (300) and a negative electrode coating layer (220) by charging. Although not shown in the drawing, the all-solid-state battery may further include a lithium metal layer disposed inside, for example, a negative electrode coating layer (220) by charging.

[0064] The lithium metal layer (240) may include lithium or a lithium alloy. Since the lithium metal layer (240) is a metal layer containing lithium, it may function as, for example, a lithium reservoir. The lithium alloy may be, for example, Li-Al alloy, Li-Sn alloy, Li-In alloy, Li-Ag alloy, Li-Au alloy, Li-Zn alloy, Li-Ge alloy, Li-Si alloy, etc., but is not limited to these; any alloy used as a lithium alloy in the relevant technical field may be possible. The lithium metal layer (240) may be composed of one of these alloys or lithium, or may be composed of various types of alloys. The lithium metal layer (240) may be, for example, a plated layer. The lithium metal layer (240) may be, for example, deposited between the negative electrode coating layer (220) and the negative electrode current collector (210) during the charging process of an all-solid-state battery.

[0065] A lithium metal layer (230) within the negative electrode (200) may be provided, for example, between the negative electrode current collector (210) and the negative electrode coating layer (220) before assembly of the all-solid-state battery. If a lithium metal layer (240) is placed between the negative electrode current collector (210) and the negative electrode coating layer (220) before assembly of the all-solid-state battery, the lithium metal layer (240) acts as a lithium reservoir because it is a metal layer containing lithium. For example, a lithium foil may be placed between the negative electrode current collector (210) and the negative electrode coating layer (220) before assembly of the all-solid-state battery.

[0066] When a lithium metal layer (240) is deposited by charging after assembly of the all-solid-state battery, the energy density of the all-solid-state battery can be increased because the lithium metal layer (240) is not included during assembly of the all-solid-state battery. When charging the all-solid-state battery, it can be charged beyond the charging capacity of the negative electrode coating layer (220). That is, the negative electrode coating layer (220) can be overcharged. At the beginning of charging, lithium can be absorbed in the negative electrode coating layer (220). If charging is performed beyond the capacity of the negative electrode coating layer (220), lithium can be deposited, for example, between the negative electrode coating layer (220) and the negative electrode current collector (210). A lithium metal layer (240) can be formed by the deposited lithium.

[0067] The lithium metal layer (240) can be composed mainly of lithium (i.e., metallic lithium). During discharge, the lithium in the lithium metal layer (240) can be ionized and move to the positive electrode (100). In other words, lithium can be used as a negative electrode active material in a solid-state battery. In addition, since the negative electrode coating layer (220) covers the lithium metal layer (240), the negative electrode coating layer (220) can protect the lithium metal layer (240) and simultaneously suppress the precipitation growth of lithium dendrites. Therefore, the negative electrode coating layer (220) can suppress short circuits and capacity degradation of the solid-state battery and improve the cycle characteristics of the solid-state battery.

[0068] When a lithium metal layer (240) is formed by charging after assembly of the all-solid-state battery, the negative electrode current collector (210), the negative electrode coating layer (220), and the region between them may be a Li-free region that does not contain lithium (Li) in the initial state or after complete discharge of the all-solid-state battery.

[0069] Referring to FIG. 3, the sulfur coating layer (230) may further include a first intermediate layer (231) adjacent to the cathode coating layer (220). Referring to FIG. 3, the sulfur coating layer (230) may further include a third intermediate layer (233) adjacent to the solid electrolyte layer (300).

[0070] The first intermediate layer (231) may further include a metal-carbon composite. The metal-carbon composite included in the first intermediate layer (231) may have the same or different composition as the metal-carbon composite included in the aforementioned cathode coating layer (220). By including the first intermediate layer (231) containing the metal-carbon composite on one surface adjacent to the cathode coating layer (220), the interfacial resistance between the cathode coating layer (220) and the sulfur coating layer (230) can be reduced. The content of the metal-carbon composite included in the first intermediate layer (231) may be 1 to 30 wt%, 1 to 25 wt%, 1 to 20 wt%, 1 to 15 wt%, or 1 to 10 wt% of the total weight of the sulfur coating layer (230).

[0071] Referring to FIG. 4, the sulfur coating layer (230) may further include a second intermediate layer (232) adjacent to the solid electrolyte layer (300). Referring to FIG. 4, the sulfur coating layer (230) may further include a third intermediate layer (233) adjacent to the cathode coating layer (220).

[0072] The second intermediate layer (232) may further include a solid electrolyte. The solid electrolyte may include a sulfide-based solid electrolyte with excellent lithium ion conductivity characteristics. Sulfide-based solid electrolytes include, for example, Li2S-P2S5, Li2S-P2S5-LiX (where X is a halogen element), Li2S-P2S5-Li2O, Li2S-P2S5-Li2O-LiI, Li2S-SiS2, Li2S-SiS2-LiI, Li2S-SiS2-LiBr, Li2S-SiS2-LiCl, Li2S-SiS2-B2S3-LiI, Li2S-SiS2-P2S5-LiI, Li2S-B2S3, Li2S-P2S5-Z m S n (m, n are positive numbers, uppercase “Z” is one of Ge, Zn, or Ga), Li2S-GeS2, Li2S-SiS2-Li3PO4, Li2S-SiS2-Li p MO q(p, q are positive numbers, uppercase “M” is one of P, Si, Ge, B, Al, Ga, In), Li 7-x PS 6-x Cl x (0≤x≤2), Li 7-x PS 6-x Br x (0≤x≤2), Li 7-x PS 6-x I x It may include (0≤x≤2) or a combination thereof.

[0073] Sulfide-based solid electrolytes are, for example, Li 7-x PS 6-x Cl x (0≤x≤2), Li 7-x PS 6-x Br x (0≤x≤2), and Li 7-x PS 6-x I x It may be an argyrodite-type compound comprising one or more selected from (0≤x≤2). In particular, the sulfide-based solid electrolyte may be an argyrodite-type compound comprising one or more selected from Li6PS5Cl, Li6PS5Br, and Li6PS5I.

[0074] Alternatively, sulfide-based solid electrolytes are Li 7-a M a PS 6-c X cIt may be an argyrodite-type compound containing (0≤a≤2, (0≤c≤2)). Here, X may be F, Br, Cl, or a combination thereof. M may be candium (Sc), yttrium (Y), titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), technetium (Tc), rhenium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), zinc (Zn), cadmium (Cd), mercury (Hg), aluminum (Al), gallium (Ga), indium (In), thallium (Tl), silicon (Si), germanium (Ge), tin (Sn), lead (Pb), arsenic (As), antimony (Sb), bismuth (Bi), or a combination thereof.

[0075] The density of the azyrodite-type solid electrolyte may be 1.5 g / cc to 2.0 g / cc. By having a density of 1.5 g / cc or higher for the azyrodite-type solid electrolyte, the internal resistance of the all-solid-state battery is reduced, and defects such as penetration and short circuit of the solid electrolyte film due to lithium dendrite formation can be prevented. The elastic modulus of the solid electrolyte may be, for example, 15 GPa to 35 GPa.

[0076] By including a second intermediate layer (232) containing a solid electrolyte on one side adjacent to the solid electrolyte layer (300) of the sulfur coating layer (230), the interfacial resistance between the solid electrolyte layer (300) and the sulfur coating layer (230) can be reduced. The content of the solid electrolyte included in the second intermediate layer (232) may be 1 to 30 wt%, 1 to 25 wt%, 1 to 20 wt%, 1 to 15 wt%, or 1 to 10 wt% of the total weight of the sulfur coating layer (230).

[0077] Referring to FIG. 5, the sulfur coating layer (230) may further include a first intermediate layer (231) adjacent to the cathode coating layer (220), a second intermediate layer (232) adjacent to the solid electrolyte layer (300), and a third intermediate layer (233) disposed between the first intermediate layer (231) and the second intermediate layer (232). The first intermediate layer (231) may further include a metal-carbon composite. The third intermediate layer (233) may further include a solid electrolyte. By including the first intermediate layer (231) adjacent to the cathode coating layer (220) and the second intermediate layer (232) adjacent to the solid electrolyte layer (300) in the sulfur coating layer (230), a sudden change in composition between the cathode coating layer (220) and the solid electrolyte layer (300) can be prevented, thereby reducing the effect of increased interfacial resistance caused by the sulfur coating layer (230). The content of the metal-carbon composite included in the first intermediate layer (231) may be 1 to 30 wt%, 1 to 25 wt%, 1 to 20 wt%, 1 to 15 wt%, or 1 to 10 wt% of the total weight of the sulfur coating layer (230). The content of the solid electrolyte included in the second intermediate layer (232) may be 1 to 30 wt%, 1 to 25 wt%, 1 to 20 wt%, 1 to 15 wt%, or 1 to 10 wt% of the total weight of the sulfur coating layer (230). The content of the sulfur-based material included in the sulfur coating layer (230) may be 40 to 100 wt%, 50 to 100 wt%, 60 to 100 wt%, 70 to 100 wt%, or 80 to 100 wt% of the total weight of the sulfur coating layer (230). The content of the sulfur-based material included in the sulfur coating layer (230) may be 40 to 99 wt%, 50 to 99 wt%, 60 to 99 wt%, 70 to 99 wt%, or 80 to 99 wt% of the total weight of the sulfur coating layer (230).

[0078] (anode)

[0079] Referring to FIG. 1, the positive electrode (100) may include a positive electrode current collector (110) and a positive electrode active material layer (120) on the positive electrode current collector (110).

[0080] The positive current collector (110) can provide a reference surface on which the positive active material layer (120) is placed. The positive current collector (110) may include, for example, a plate or foil comprising indium (In), copper (Cu), magnesium (Mg), stainless steel (SUS), titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), lithium (Li), or an alloy thereof. The positive current collector (110) may be omitted. Although not illustrated, a carbon layer with a thickness of 0.1 μm to 4 μm may be further disposed between the positive current collector (110) and the positive active material layer (120) to increase the bonding strength between the positive current collector (110) and the positive active material layer (120). The carbon layer may include amorphous carbon, crystalline carbon, etc.

[0081] The positive active material layer (120) may include a positive active material and a solid electrolyte. The solid electrolyte may be the same as or different from any one of the materials that may be included in the solid electrolyte included in the aforementioned sulfur coating layer (240).

[0082] The cathode active material may include a lithium-containing sulfide-based cathode active material. A lithium-containing sulfide-based cathode active material is, for example, an electrode material to which lithium is added to a sulfur-based cathode active material. The lithium-containing sulfide-based cathode active material may include, for example, Li2S, a Li2S-containing composite, or a combination thereof. By including Li2S, a Li2S-containing composite, or a combination thereof having high capacity as the lithium-containing sulfide-based cathode active material, the use of lithium metal may be omitted during the manufacture of secondary batteries. Since lithium metal has high reactivity and great ductility, it can reduce mass producibility during battery manufacturing. Therefore, if the use of lithium metal is omitted during the manufacture of secondary batteries, the mass producibility of the secondary battery may be improved.

[0083] A Li2S-containing composite is, for example, a composite of Li2S and a conductive material. The conductive material is, for example, an ionic conductive material, an electronic conductive material, or a combination thereof.

[0084] The ionic conductivity of an ion-conducting material is, for example, 1.0 × 10⁻⁶ at 25°C. -5 S / m or greater, 1.0×10 -4 S / m or more, or 1.0×10 -3 It is greater than S / m. The ion-conducting material may have pores. By having pores, Li2S can be contained within the pores, which can increase the contact area between Li2S and the ion-conducting material and increase the specific surface area of ​​Li2S. The form of the ion-conducting material may be, for example, particulate ion-conducting material, plate-shaped ion-conducting material, rod-shaped ion-conducting material, or a combination thereof, but is not necessarily limited to these.

[0085] An ion-conducting material according to one embodiment may include, for example, a metal salt compound. The metal salt compound may include a lithium salt compound. The lithium salt compound may include, for example, LiF, LiCl, LiBr, LiI, or a combination thereof. According to one embodiment, a Li2S-containing composite comprising a lithium salt compound may include, for example, Li2S-LiF, Li2S-LiCl, Li2S-LiBr, Li2S-LiI, or a combination thereof. The metal salt compound may further include a boron group metal halide salt. The boron group metal halide salt may include, for example, AlF3, AlCl3, AlBr3, AlI3GaF3, GaCl3, GaBr3, GaI3InF3, InCl3, InBr3, InI3T1F3, T1Cl3, T1Br3, T1I3, or a combination thereof. According to one embodiment, a Li2S-containing composite further comprising a boron group metal halide salt is, for example, Li2S-LiF-AlF3, Li2S-LiF-AlCl3, Li2S-LiF-AlBr3, Li2S-LiF-AlI3, Li2S-LiF-GaF3, Li2S-LiF-GaCl3, Li2S-LiF-GaBr3, Li2S-LiF-GaI3, Li2S-LiF-InF3, Li2S-LiF-InCl3, Li2S-LiF-InBr3, Li2S-LiF-InI3, Li2S-LiF-TlF3, Li2S-LiF-TlCl3, Li2S-LiF-TlBr3, Li2S-LiF-TlI3, Li2S-LiCl-AlF3, Li2S-LiCl-AlCl3, Li2S-LiCl-AlBr3, Li2S-LiCl-AlI3, Li2S-LiCl-GaF3, Li2S-LiCl-GaCl3, Li2S-LiCl-GaBr3, Li2S-LiCl-GaI3, Li2S-LiCl-InF3, Li2S-LiCl-InCl3, Li2S-LiCl-InBr3, Li2S-LiCl-InI3, Li2S-LiCl-TlF3, Li2S-LiCl-TlCl3, Li2S-LiCl-TlBr3, Li2S-LiCl-TlI3, Li2S-LiBr-AlF3,Li2S-LiBr-AlCl3, Li2S-LiBr-AlBr3, Li2S-LiBr-AlI3, Li2S-LiBr-GaF3, Li2S-LiBr-GaCl3, Li2S-LiBr-GaBr3, Li2S-LiBr-GaI3, Li2S-LiBr-InF3, Li2S-LiBr-InCl3, Li2S-LiBr-InBr3, Li2S-LiBr-InI3, Li2S-LiBr-TlF3, Li2S-LiBr-TlCl3, Li2S-LiBr-TlBr3, Li2S-LiBr-TlI3, Li2S-LiI-AlF3, Li2S-LiI-AlCl3, Li2S-LiI-AlBr3, Li2S-LiI-AlI3, Li2S-LiI-GaF3, Li2S-LiI-GaCl3, Li2S-LiI-GaBr3, It may include Li2S-LiI-GaI3, Li2S-LiI-InF3, Li2S-LiI-InCl3, Li2S-LiI-InBr3, Li2S-LiI-InI3, Li2S-LiI-TlF3, Li2S-LiI-TlCl3, Li2S-LiI-TlBr3, Li2S-LiI-TlI3 or a combination thereof.

[0086] The electronic conductivity of an electronically conductive material is, for example, 1.0 × 10⁻⁶ at 25°C. 3 S / m or greater, 1.0×10 4 S / m or more, or 1.0×10 5It is S / m or greater. The form of the electronically conductive material is, for example, particulate electronically conductive material, plate-shaped electronically conductive material, rod-shaped electronically conductive material, or a combination thereof, but is not necessarily limited to these. The electronically conductive material may be, for example, carbon, metal powder, metal compound, etc. When carbon is included as the electronically conductive material, a secondary battery having a high energy density per unit mass can be realized because carbon has high electronic conductivity and is lightweight. The electronically conductive material may have pores. By having pores in the electronically conductive material, Li2S can be contained within the pores, which can increase the contact area between Li2S and the electronically conductive material and increase the specific surface area of ​​Li2S. The pore capacity is, for example, 0.1 cc / g to 20.0 cc / g, 0.5 cc / g to 10 cc / g, or 0.5 cc / g to 5 cc / g. The average pore diameter is, for example, 1 nm to 100 nm, 1 nm to 50 nm, or 1 nm to 20 nm. The BET specific surface area of ​​the electron-conducting material having pores is 200 m² when the average pore diameter is 15 nm or less. 2 / g to 4500 m 2 / g, and if the average pore diameter is greater than 15 nm, 100 m 2 / g to 2500 m 2 It is / g. BET specific surface area, pore diameter, pore capacity, and average pore diameter can be obtained, for example, using the nitrogen adsorption method.

[0087] An electronically conductive material according to one embodiment may include, for example, carbon. Carbon may be any material containing carbon atoms, for example, used as a conductive material in the art. Carbon may be, for example, crystalline carbon, amorphous carbon, or a combination thereof. Carbon may be, for example, a calcined product of a carbon precursor. Carbon may be, for example, a carbon nanostructure. The carbon nanostructure may be, for example, a one-dimensional carbon nanostructure, a two-dimensional carbon nanostructure, a three-dimensional carbon nanostructure, or a combination thereof. The carbon nanostructure may be, for example, a carbon nanotube (CNT), a carbon nanofiber (CNF), a carbon nanobelt, a carbon nanorod, graphene, graphene oxide (GO), reduced graphene oxide (rGO), a graphene ball (GB), or a combination thereof. Carbon may be, for example, porous carbon or non-porous carbon. Porous carbon may include, for example, periodic and regular two-dimensional or three-dimensional pores. Porous carbon may be, for example, carbon black such as Ketjen black, acetylene black, Denka black, thermal black, Channel black; graphite, activated carbon, or a combination thereof. The form of carbon may be, for example, particle form, sheet form, flake form, etc., but is not limited thereto, and any form used as carbon in the relevant technical field is possible. The method of manufacturing a composite of Li2S or a Li2S-containing composite and carbon may be a dry method, a wet method, or a combination thereof, but is not limited thereto, and the method of manufacturing a composite of Li2S, a Li2S-containing composite and carbon in the relevant technical field may be, for example, milling, heat treatment, deposition, etc., but is not necessarily limited thereto, and any method used in the relevant technical field is possible. According to one embodiment, a Li2S-containing composite containing carbon may include, for example, Li2S-CNT, Li2S-CNF, or a combination thereof.

[0088] A Li2S-containing composite according to one embodiment may include a composite of Li2S, an ion-conducting material, and an electronically conductive material. According to one embodiment, a Li2S-containing composite comprising a composite of Li2S, an ion-conducting material, and an electron-conducting material is, for example, Li2S-LiF-CNT, Li2S-LiCl-CNT, Li2S-LiBr-CNT, Li2S-LiI-CNT, Li2S-LiF-CNF, Li2S-LiCl-CNF, Li2S-LiBr-CNF, Li2S-LiI-CNF, Li2S-LiF-AlF3-CNT, Li2S-LiF-AlCl3-CNT, Li2S-LiF-AlBr3-CNT, Li2S-LiF-AlI3-CNT, Li2S-LiF-GaF3-CNT, Li2S-LiF-GaCl3-CNT, Li2S-LiF-GaBr3-CNT, Li2S-LiF-GaI3-CNT, Li2S-LiF-InF3-CNT, Li2S-LiF-InCl3-CNT, Li2S-LiF-InBr3-CNT, Li2S-LiF-InI3-CNT, Li2S-LiF-TlF3-CNT, Li2S-LiF-TlCl3-CNT, Li2S-LiF-TlBr3-CNT, Li2S-LiF-TlI3-CNT, Li2S-LiCl-AlF3-CNT, Li2S-LiCl-AlCl3-CNT, Li2S-LiCl-AlBr3-CNT, Li2S-LiCl-AlI3-CNT, Li2S-LiCl-GaF3-CNT, Li2S-LiCl-GaCl3-CNT, Li2S-LiCl-GaBr3-CNT, Li2S-LiCl-GaI3-CNT, Li2S-LiCl-InF3-CNT, Li2S-LiCl-InCl3-CNT, Li2S-LiCl-InBr3-CNT, Li2S-LiCl-InI3-CNT, Li2S-LiCl-TlF3-CNT, Li2S-LiCl-TlCl3-CNT, Li2S-LiCl-TlBr3-CNT, Li2S-LiCl-TlI3-CNT, Li2S-LiBr-AlF3-CNT, Li2S-LiBr-AlCl3-CNT, Li2S-LiBr-AlBr3-CNT, Li2S-LiBr-AlI3-CNT, Li2S-LiBr-GaF3-CNT,Li2S-LiBr-GaCl3-CNT, Li2S-LiBr-GaBr3-CNT, Li2S-LiBr-GaI3-CNT, Li2S-LiBr-InF3-CNT, Li2S-LiBr-InCl3-CNT, Li2S-LiBr-InBr3-CNT, Li2S-LiBr-InI3-CNT, Li2S-LiBr-TlF3-CNT, Li2S-LiBr-TlCl3-CNT, Li2S-LiBr-TlBr3-CNT, Li2S-LiBr-TlI3-CNT, Li2S-LiI-AlF3-CNT, Li2S-LiI-AlCl3-CNT, Li2S-LiI-AlBr3-CNT, Li2S-LiI-AlI3-CNT, Li2S-LiI-GaF3-CNT, Li2S-LiI-GaCl3-CNT, Li2S-LiI-GaBr3-CNT, Li2S-LiI-GaI3-CNT, Li2S-LiI-InF3-CNT, Li2S-LiI-InCl3-CNT, Li2S-LiI-InBr3-CNT, Li2S-LiI-InI3-CNT, Li2S-LiI-TlF3-CNT, Li2S-LiI-TlCl3-CNT, Li2S-LiI-TlBr3-CNT, Li2S-LiI-TlI3-CNT, Li2S-LiF-AlF3-CNF, Li2S-LiF-AlCl3-CNF, Li2S-LiF-AlBr3-CNF, Li2S-LiF-AlI3-CNF, Li2S-LiF-GaF3-CNF, Li2S-LiF-GaCl3-CNF, Li2S-LiF-GaBr3-CNF, Li2S-LiF-GaI3-CNF, Li2S-LiF-InF3-CNF, Li2S-LiF-InCl3-CNF, Li2S-LiF-InBr3-CNF, Li2S-LiF-InI3-CNF, Li2S-LiF-TlF3-CNF, Li2S-LiF-TlCl3-CNF, Li2S-LiF-TlBr3-CNF, Li2S-LiF-TlI3-CNF, Li2S-LiCl-AlF3-CNF, Li2S-LiCl-AlCl3-CNF, Li2S-LiCl-AlBr3-CNF, Li2S-LiCl-AlI3-CNF, Li2S-LiCl-GaF3-CNF, Li2S-LiCl-GaCl3-CNF, Li2S-LiCl-GaBr3-CNF,Li2S-LiCl-GaI3-CNF, Li2S-LiCl-InF3-CNF, Li2S-LiCl-InCl3-CNF, Li2S-LiCl-InBr3-CNF, Li2S-LiCl-InI3-CNF, Li2S-LiCl-TlF3-CNF, Li2S-LiCl-TlCl3-CNF, Li2S-LiCl-TlBr3-CNF, Li2S-LiCl-TlI3-CNF, Li2S-LiBr-AlF3-CNF, Li2S-LiBr-AlCl3-CNF, Li2S-LiBr-AlBr3-CNF, Li2S-LiBr-AlI3-CNF, Li2S-LiBr-GaF3-CNF, Li2S-LiBr-GaCl3-CNF, Li2S-LiBr-GaBr3-CNF, Li2S-LiBr-GaI3-CNF, Li2S-LiBr-InF3-CNF, Li2S-LiBr-InCl3-CNF, Li2S-LiBr-InBr3-CNF, Li2S-LiBr-InI3-CNF, Li2S-LiBr-TlF3-CNF, Li2S-LiBr-TlCl3-CNF, Li2S-LiBr-TlBr3-CNF, Li2S-LiBr-TlI3-CNF, Li2S-LiI-AlF3-CNF, Li2S-LiI-AlCl3-CNF, Li2S-LiI-AlBr3-CNF, Li2S-LiI-AlI3-CNF, Li2S-LiI-GaF3-CNF, Li2S-LiI-GaCl3-CNF, Li2S-LiI-GaBr3-CNF, Li2S-LiI-GaI3-CNF, Li2S-LiI-InF3-CNF, Li2S-LiI-InCl3-CNF, Li2S-LiI-InBr3-CNF, Li2S-LiI-InI3-CNF, Li2S-LiI-TlF3-CNF, Li2S-LiI-TlCl3-CNF, Li2S-LiI-TlBr3-CNF, 또는 Li2S-LiI-TlI3-CNF, 또는 이들의 임의의 조합을 포함할 수 있다.,

[0089] The positive active material layer (120) may include a solid electrolyte. The solid electrolyte included in the positive active material layer may include a sulfide-based solid electrolyte with excellent lithium ion conductivity characteristics. The sulfide-based solid electrolyte may be the same as or different from the sulfide-based solid electrolyte included in the aforementioned solid electrolyte layer (300). A detailed description of the sulfide-based solid electrolyte is omitted below, as the content regarding the sulfide-based solid electrolyte included in the aforementioned solid electrolyte layer (300) can be applied as is.

[0090] The positive active material layer (120) may further include a conductive material. The conductive material may have conductivity without causing chemical changes in the all-solid-state battery (10), thereby increasing the conductivity of the positive active material and the solid electrolyte. The conductive material may include a carbon-based material. The conductive material may include, for example, at least one of graphite, carbon black, acetylene black, carbon nanofiber, or carbon nanotube. Meanwhile, the positive active material layer (120) may omit the conductive material.

[0091] The positive active material layer (120) may further include a binder. The binder included in the positive active material layer (120) is, for example, styrene-butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, etc., but is not limited to these and any binder used in the relevant technical field is possible. In another embodiment, the binder may be omitted.

[0092] (Solid electrolyte layer)

[0093] Referring to FIG. 1, a solid electrolyte layer (300) may be disposed between an anode (100) and a cathode (200). The solid electrolyte layer (300) may include a solid electrolyte and a binder.

[0094] Solid electrolytes may include, for example, sulfide-based solid electrolytes, oxide-based solid electrolytes, polymeric solid electrolytes, or combinations thereof.

[0095] The sulfide-based solid electrolyte may be the same as or different from any one of the materials that can be included in the solid electrolyte included in the aforementioned sulfur coating layer (240).

[0096] Oxide-based solid electrolytes are, for example, Li 1+x+y Al x Ti 2-x Si y P 3-y O 12 (0 <x<2, 0≤y<3), BaTiO3, Pb(Zr,Ti)O3(PZT), Pb 1-x La x Zr 1-y Ti y O3(PLZT)(0≤x<1, 0≤y<1), PB(Mg3Nb 2 / 3 )O3-PbTiO3(PMN-PT), HfO2, SrTiO3, SnO2, CeO2, Na2O, MgO, NiO, CaO, BaO, ZnO, ZrO2, Y2O3, Al2O3, TiO2, SiO2, Li3PO4, Li x Ti y (PO4)3(0 <x<2, 0<y<3), Li x Al y Ti z (PO4)3(0 <x<2, 0<y<1, 0<z<3), Li 1+x+y (Al, Ga) x (Ti, Ge) 2-x Si y P 3-y O 12 (0≤x≤1, 0≤y≤1), Li x La y TiO3(0 <x<2, 0<y<3), Li2O, LiOH, Li2CO3, LiAlO2, Li2O-Al2O3-SiO2-P2O5-TiO2-GeO2, Li 3+x La3M2O 12(M = Te, Nb, or Zr, 0≤x≤10), or a combination thereof. Oxide-based solid electrolytes are produced, for example, by sintering.

[0097] Oxide-based solid electrolytes are, for example, Li7La3Zr2O 12 (LLZO) and Li 3+x La3Zr 2-a M a O 12 (M-doped LLZO, M=Ga, W, Nb, Ta, or Al(0 <a<2, 0≤x≤10) 중에서 선택된 가넷계(Garnet-type) 고체 전해질이다.

[0098] The polymer solid electrolyte may, for example, comprise a mixture of a lithium salt and a polymer, or comprise a polymer having ion-conducting functional groups. The polymer solid electrolyte may, for example, be a polymer electrolyte in a solid state at 25°C and 1 atm. The polymer solid electrolyte may, for example, not contain a liquid.The polymeric solid electrolyte comprises a polymer, wherein the polymer is, for example, polyethylene oxide (PEO), polyvinylidene fluoride (PVDF), vinylidene fluoride-hexafluoropropylene (PVDF-HFP), polyethylene oxide (PEO), poly(styrene-b-ethylene oxide) block copolymer (PS-PEO), poly(styrene-butadiene), poly(styrene-isoprene-styrene), poly(styrene-b-divinylbenzene) block copolymer, poly(styrene-ethylene oxide-styrene) block copolymer, polystyrene sulfonate (PSS), polyvinyl fluoride (PVF), poly(methylmethacrylate) (PMMA), polyethylene glycol (PEG), polyacrylonitrile (PAN), polytetrafluoroethylene (PTFE), polyethylenedioxythiophene (PEDOT), polypyrrole (PPY), polyacrylonitrile (PAN), Polyaniline, Polyacetylene, Nafion, Aquivion, Flemion, Gore, Aciplex, Morgane ADP, Sulfonated poly(ether ether ketone) (SPEEK), Sulfonated poly(arylene ether ketone ketone sulfone) (SPAEKKS), Sulfonated poly(arylether ketone) (SPAEK), Poly[bis(benzimidazobenzisoquinolinones)] (SPBIBI), Poly(styrene sulfonate) (PSS), Lithium 9,10-Diphenylanthracene-2-sulfonate (lithium 9,10-diphenylanthracene-2-sulfonate, DPASLi. +It may be ) or a combination thereof, but is not limited thereto, and any that are used in polymer electrolytes in the relevant technical field are permitted. Any lithium salt that can be used as a lithium salt in the relevant technical field is permitted. Examples of lithium salts include LiPF6, LiBF4, LiSbF6, LiAsF6, LiClO4, LiCF3SO3, Li(CF3SO2)2N, LiC4F9SO3, LiAlO2, LiAlCl4, LiN(C x F2 x+1 SO2)(C y F 2y+1 The polymer may be SO2)(x and y are each 1 to 20), LiCl, LiI, or a mixture thereof. The polymer included in the polymer solid electrolyte may be, for example, a compound containing 10 or more, 20 or more, 50 or more, or 100 or more repeating units. The weight-average molecular weight of the polymer included in the polymer solid electrolyte may be, for example, 1,000 Dalton or more, 10,000 Dalton or more, 100,000 Dalton or more, or 1,000,000 Dalton or more.

[0099] The solid electrolyte layer (300) may further include, for example, a binder. The binder included in the solid electrolyte layer (300) may be, for example, styrene-butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, etc., but is not limited to these and any binder used in the relevant technical field is possible. The binder of the solid electrolyte layer (300) may be the same as or different from the binder included in the positive electrode active material layer (120) and the negative electrode coating layer (230). The binder may be omitted.

[0100] The binder content included in the solid electrolyte layer (300) is 0.1 to 10 wt%, 0.1 to 5 wt%, 0.1 to 3 wt%, 0.1 to 1 wt%, 0 to 0.5 wt%, or 0 to 0.1 wt% based on the total weight of the solid electrolyte layer (300).

[0101] Hereinafter, with reference to FIGS. 6 and 7, an all-solid-state battery according to another embodiment will be described. Hereinafter, regarding the all-solid-state battery disclosed in FIGS. 6 and 7, detailed descriptions of configurations, functions, features, and operations that overlap with those described above in FIGS. 1 to 5 will be omitted, and the differences will be described in detail.

[0102] Referring to FIG. 6, an all-solid-state battery according to one embodiment comprises: a positive electrode (100) including a positive active material layer (120); a negative electrode (200) including a negative current collector (210) and a negative coating layer (220) on the negative current collector (210); a solid electrolyte layer (300) disposed between the positive electrode (100) and the negative electrode (200); and a protective layer (400) disposed between the negative coating layer (220) and the solid electrolyte layer (300); wherein the protective layer (400) may include a metal carbon composite, sulfur-based materials, and a solid electrolyte.

[0103] The protective layer (400) can suppress side reactions occurring between the negative electrode coating layer (220) and the solid electrolyte layer (300) during charging and discharging of the all-solid-state battery by including electrochemically stable sulfur-based materials. The protective layer (400) can suppress excessive growth of lithium dendrites by including sulfur-based materials with excellent physical properties. An all-solid-state battery including such a protective layer (400) can have improved lifespan characteristics. The sulfur-based materials included in the protective layer (400) may include S (Sulfur), S8 (Octasulfur), H2S, Li3PO4, LiCl, Li2S, SO2, SO3, or a combination thereof. The sulfur-based materials included in the protective layer (400) may include S (Sulfur), S8 (Octasulfur), Li2S8, Li2S6, Li2S4, Li2S2, Li2S, or a combination thereof.

[0104] The content of sulfur atoms (S) included in the protective layer (400) may be 30 at% to 100 at% with respect to the total atomic content included in the protective layer (400). For example, the content of sulfur atoms (S) included in the protective layer (400) may be 40 at% to 100 at%, 45 at% to 100 at%, or 50 at% to 100 at% with respect to the total atomic content included in the protective layer (400). For example, the content of sulfur atoms (S) included in the protective layer (400) may be 30 at% to 99 at%, 40 at% to 99 at%, or 50 at% to 99 at% with respect to the total atomic content included in the protective layer (400).

[0105] The metal-carbon composite included in the protective layer (400) may have the same or different composition as the metal-carbon composite included in the cathode coating layer (220). The metal-carbon composite included in the protective layer (400) is a composite of amorphous carbon and metal particles, and the metal particles may include gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), zinc (Zn), or a combination thereof. By including the metal-carbon composite in the protective layer (400), the interfacial resistance between the cathode coating layer (220) and the protective layer (400) can be reduced.

[0106] The solid electrolyte included in the protective layer (400) may have the same or different composition as the solid electrolyte included in the solid electrolyte layer (300). The solid electrolyte included in the protective layer (400) is a sulfide-based solid electrolyte, and the sulfide-based solid electrolyte is Li 7-x PS 6-x Cl x (0≤x≤2), Li 7-x PS 6-x Br x (0≤x≤2), Li 7-x PS 6-x I x It may include (0≤x≤2) or a combination thereof. By including a solid electrolyte in the protective layer (400), the interfacial resistance between the solid electrolyte layer (300) and the protective layer (400) can be reduced.

[0107] The thickness of the protective layer (400) may be, for example, 30% or more of the thickness of the cathode coating layer (220). The thickness of the protective layer (400) may be, for example, 35% or more, 40% or more, 45% or more, or 50% or more of the thickness of the cathode coating layer (220). The thickness of the protective layer (400) may be, for example, 150% or less of the thickness of the cathode coating layer (220). The thickness of the protective layer (400) may be, for example, 150% or less, 145% or less, 140% or less, 135% or less, or 130% or less of the thickness of the cathode coating layer (220). The thickness of the protective layer (400) may be, for example, 1.5㎛ to 7.5㎛, 2㎛ to 7㎛, or 2.5㎛ to 6.5㎛. If the thickness of the protective layer (400) is excessively thin, the effect of suppressing side reactions occurring between the cathode coating layer (220) and the solid electrolyte layer (300) may be minimal. If the thickness of the protective layer (400) is excessively thick, the interfacial resistance between the cathode coating layer (220) and the solid electrolyte layer (300) may increase.

[0108] Referring to FIG. 7, the protective layer (400) may further include a first protective layer (410) adjacent to the cathode coating layer (220) and a second protective layer (420) adjacent to the solid electrolyte layer (300).

[0109] The content of the sulfur-based material in the first protective layer (410) may be greater than the content of the sulfur-based material in the second protective layer (420). The content of sulfur atoms (S) contained in the first protective layer (410) may be greater than the content of sulfur atoms (S) contained in the second protective layer (420). In this case, even if some sulfur atoms (S) within the protective layer (400) move as the cycle of the all-solid-state battery progresses, a rapid change in composition between the negative electrode coating layer (220) and the solid electrolyte layer (300) can be prevented, thereby reducing the effect of increased interfacial resistance caused by the protective layer (400).

[0110] The content of the sulfur-based material in the second protective layer (420) may be greater than the content of the sulfur-based material in the first protective layer (410). The content of sulfur atoms (S) contained in the second protective layer (420) may be greater than the content of sulfur atoms (S) contained in the first protective layer (410). In this case, the effect of increasing interfacial resistance caused by the protective layer (400) can be reduced by preventing a sudden change in composition between the cathode coating layer (220) and the solid electrolyte layer (300).

[0111] (Method for manufacturing all-solid-state batteries)

[0112] A method for manufacturing an all-solid-state battery according to another embodiment may include providing a positive electrode; providing a negative electrode comprising a negative current collector and a negative electrode coating layer on the negative current collector; providing a solid electrolyte layer between the positive electrode and the negative electrode; and forming a sulfur coating layer between the negative electrode and the solid electrolyte layer.

[0113] A sulfur coating layer can be formed, for example, by coating a sulfur-based material on one side of a cathode coating layer. Alternatively, a sulfur coating layer can be formed, for example, by coating a sulfur-based material on one side of a solid electrolyte layer. Methods for coating sulfur-based materials may include, for example, physical vapor deposition (PVD), chemical vapor deposition (CVD), or spray coating, but are not necessarily limited thereto.

[0114] Forming a sulfur coating layer may include, for example, preparing a free-standing membrane containing sulfur-based materials; and placing said free-standing membrane between said cathode and said solid electrolyte layer. A method for forming a free-standing membrane containing sulfur-based materials may be prepared by depositing sulfur-based materials on a thin film and then peeling off the film, or by directly compressing sulfur-based materials to form the free-standing membrane, but is not necessarily limited thereto.

[0115] An all-solid-state battery can be manufactured by placing a solid electrolyte layer between the anode and the cathode, forming a sulfur coating layer by the method described above so that the sulfur coating layer is placed between the cathode and the solid electrolyte layer, and then laminating and pressurizing. Pressurization is performed, for example, at a temperature of room temperature to 90°C or lower, or at a temperature of 20°C to 90°C. Alternatively, pressurization is performed at a high temperature of 100°C or higher. The time for which pressurization is applied is, for example, 30 minutes or less, 20 minutes or less, 15 minutes or less, or 10 minutes or less. The time for which pressurization is applied is 1 ms to 30 minutes, 1 ms to 20 minutes, 1 ms to 15 minutes, or 1 ms to 10 minutes. The pressurization method may be, for example, isotactic press, roll press, flat press, etc., but is not necessarily limited to these methods, and any pressurization method used in the relevant technical field is possible. The pressure applied during pressurization is, for example, 500 MPa or less, 480 MPa or less, 450 MPa or less, 400 MPa or less, 350 MPa or less, 300 MPa or less, 250 MPa or less, 200 MPa or less, 150 MPa or less, or 100 MPa or less. The pressure applied during pressurization is, for example, 50 MPa to 500 MPa, 50 MPa to 480 MPa, 50 MPa to 450 MPa, 50 MPa to 400 MPa, 50 MPa to 350 MPa, 50 MPa to 300 MPa, 50 MPa to 250 MPa, 50 MPa to 200 MPa, 50 MPa to 150 MPa, 50 MPa to or 100 MPa. Under such pressure, for example, solid electrolyte powder is sintered to form a single solid electrolyte layer.

[0116] The configuration and manufacturing method of the all-solid-state battery described above are examples of embodiments, and the constituent members and manufacturing procedures, etc., can be appropriately modified.

[0117] The creative idea is explained in more detail through the following examples and comparative examples. However, the examples are intended to illustrate the creative idea and do not limit the scope of the creative idea to these examples alone.

[0118]

[0119] Comparative Example 1: Cathode coating layer / solid electrolyte layer

[0120] (Anode manufacturing)

[0121] A metal halide salt mixture was prepared by mixing LiI powder and AlI3 powder in a mass ratio of 5:15. A Li2S-LiI-AlI3 composite was prepared by mixing Li2S and the prepared metal halide salt powder in a mass ratio of 40:20 and then performing ball milling. The milling conditions were 25°C and 600 rpm for 10 hours. The milling energy applied to the sample during milling was 28 G. The composite and CNF were mixed in a weight ratio of 60:10. The mixture was mechanically milled using a ball mill to prepare a Li2S-LiI-AlI3-CNF composite. The milling conditions were 25°C and 600 rpm for 10 hours. The milling energy applied to the sample during milling was 28 G. The Li2S-LiI-AlI3-CNF composite was used as the cathode active material. Li6PS5Cl, an argyrodite-type crystal (D50=3.0 μm, crystalline), was prepared as a solid electrolyte. PTFE was prepared as a binder. These materials were mixed in a weight ratio of positive active material : solid electrolyte : binder = 70 : 30 : 1.2 to prepare a positive composite. The positive composite was obtained by dry mixing using a ball mill.

[0122] An anode was manufactured by placing the anode composite on one side of an anode current collector made of aluminum foil coated with carbon on one side and performing a plate press at a pressure of 200 MPa for 10 minutes. The thickness of the anode was approximately 120 μm. The thickness of the anode active material layer was approximately 100 μm, and the thickness of the carbon-coated aluminum foil was approximately 20 μm. The area of ​​the anode active material layer and the anode current collector were the same.

[0123] (Cathode manufacturing)

[0124] A SUS foil with a thickness of 10 μm was prepared as a cathode current collector. Carbon black (CB) with a primary particle size of about 30 nm and silver (Ag) particles with an average particle diameter of about 60 nm were prepared.

[0125] 4 g of a mixed powder, prepared by mixing carbon black (CB) and silver (Ag) particles in a weight ratio of 3:1, was placed in a container, and 4 g of an NMP solution containing 7 wt% of a PVDF binder (Kureha # 9300) was added to prepare a mixed solution. A slurry was prepared by stirring the mixed solution while gradually adding NMP to it. The prepared slurry was applied to a SUS sheet using a bar coater, dried in air at 80°C for 10 minutes, and then vacuum dried at 40°C for 10 hours to prepare a laminate. The prepared laminate was cold-roll-pressed to flatten the surface, thereby preparing a cathode having a cathode coating layer / cathode current collector structure. The thickness of the cathode coating layer was approximately 5 μm. The surface area of ​​the cathode coating layer and the cathode current collector were the same.

[0126] (Preparation of solid electrolyte layer)

[0127] A mixture was prepared by adding 1.5 parts by weight of an acrylic binder to 98.5 parts by weight of a solid electrolyte (D50=3.0 (m, crystalline)) which is an argyrodite-type crystal. A slurry was prepared by stirring while adding octyl acetate to the prepared mixture. The prepared slurry was applied using a bar coater onto a 15 μm thick nonwoven fabric placed on a 75 μm thick PET substrate, and a laminate was prepared by drying in air at a temperature of 80 °C for 10 minutes. A solid electrolyte layer was prepared by vacuum drying the prepared laminate at 80 °C for 2 hours.

[0128] (Manufacturing of all-solid-state batteries)

[0129] A solid electrolyte layer was placed on the cathode such that the cathode coating layer contacted the solid electrolyte layer, and an anode was placed on the solid electrolyte layer. The prepared laminate was subjected to plate pressing at 85 °C and a pressure of 500 MPa for 30 min. This pressing treatment sintered the solid electrolyte layer, thereby improving battery characteristics. The thickness of the sintered solid electrolyte layer was approximately 45 μm. The density of the Li6PS5Cl solid electrolyte, an argyrodite-type crystal contained in the sintered solid electrolyte layer, was 1.6 g / cc.

[0130] An all-solid-state secondary battery was manufactured by placing a pressurized laminate into a pouch and vacuum sealing it. Parts of the positive and negative current collectors were extended outside the sealed battery to be used as the positive and negative terminals.

[0131]

[0132] Example 1: Cathode coating layer / Sulfur coating layer (coated on the cathode side) / Solid electrolyte layer

[0133] An all-solid-state battery was fabricated using the same method as Comparative Example 1, except that a sulfur coating layer was formed on the cathode prepared in Comparative Example 1 using a Physical Vapor Deposition (PVD) process. A high-purity sulfur target was used as the source material to form the sulfur coating layer, and the PVD process was carried out for about 10 minutes inside a reaction chamber under vacuum conditions at 100°C. The thickness of the sulfur coating layer formed was about 5 μm.

[0134] Example 2: Cathode coating layer / Sulfur coating layer (coated on the solid electrolyte side) / Solid electrolyte layer

[0135] An all-solid-state battery was fabricated using the same method as Comparative Example 1, except that a sulfur coating layer was formed on the solid electrolyte layer prepared in Comparative Example 1 using a Physical Vapor Deposition (PVD) process. To form the sulfur coating layer, a high-purity sulfur target was used as the source material, and the PVD process was carried out for about 10 minutes inside a reaction chamber under vacuum conditions at 100°C. The thickness of the sulfur coating layer formed was about 5 μm.

[0136] Example 3: Cathode coating layer / Sulfur coating layer (coated on the cathode and solid electrolyte side) / Solid electrolyte layer

[0137] An all-solid-state battery was fabricated using the same method as Comparative Example 1, except that a sulfur coating layer was formed on each of the solid electrolyte layer and the cathode coating layer prepared in Comparative Example 1 using a Physical Vapor Deposition (PVD) process. To form the sulfur coating layer, a high-purity sulfur target was used as the source material, and the PVD process was carried out for about 10 minutes inside a reaction chamber under vacuum conditions at 100°C, and the thickness of the sulfur coating layer formed was about 5 μm.

[0138] Example 4: Cathode coating layer / Sulfur coating layer (self-supporting film, Ag-C + S) / Solid electrolyte layer

[0139] 5 g of 99% pure sulfur powder and 5 g of a mixed powder consisting of carbon black (CB) and silver (Ag) particles in a weight ratio of 3:1 were prepared. A sheet-shaped self-standing film was prepared by feeding the sulfur powder and the mixed powder into an extruder without a separate solvent. The extrusion pressure was 60 MPa. The prepared self-standing film was rolled to prepare a rolled self-standing film. The rolling pressure was 3.5 ton / cm² 2 It was. The thickness of the self-supporting film was about 5 μm.

[0140] An all-solid-state battery was fabricated using the same method as Comparative Example 1, except that the all-solid-state battery was fabricated through a laminate in which a self-supporting film layer was placed between the cathode and the solid electrolyte layer prepared in Comparative Example 1.

[0141] Example 5: Cathode coating layer / Sulfur coating layer (multilayer self-supporting film) / Solid electrolyte layer

[0142] 4 g of sulfur powder with 99% purity and 1 g of mixed powder was prepared by mixing carbon black (CB) and silver (Ag) particles in a weight ratio of 3:1. The sulfur powder and the mixed powder were fed into an extruder without a separate solvent to prepare a first-layer self-standing film in the form of a sheet.

[0143] 1 g of sulfur powder with 99% purity and 4 g of mixed powder were prepared by mixing carbon black (CB) and silver (Ag) particles in a weight ratio of 3:1. The sulfur powder and the mixed powder were fed into an extruder without a separate solvent to prepare a sheet-shaped second-layer self-standing film.

[0144] An all-solid-state battery was fabricated using the same method as Comparative Example 1, except that a laminate was fabricated by placing a first-layer self-supporting film adjacent to a cathode coating layer and a second-layer self-supporting film adjacent to a solid electrolyte layer. The thickness of the first-layer self-supporting film was 2.5 μm. The thickness of the second-layer self-supporting film was 2.5 μm.

[0145] Example 6: Cathode coating layer / Sulfur coating layer (multilayer self-supporting film) / Solid electrolyte layer

[0146] 1 g of sulfur powder with 99% purity and 4 g of mixed powder, in which carbon black (CB) and silver (Ag) particles were mixed in a weight ratio of 3:1, were prepared. The sulfur powder and the mixed powder were fed into an extruder without a separate solvent to prepare a first-layer self-standing film in the form of a sheet.

[0147] 4 g of sulfur powder with 99% purity and 1 g of mixed powder was prepared by mixing carbon black (CB) and silver (Ag) particles in a weight ratio of 3:1. The sulfur powder and the mixed powder were fed into an extruder without a separate solvent to prepare a sheet-shaped second-layer self-standing film.

[0148] An all-solid-state battery was fabricated using the same method as Comparative Example 1, except that a laminate was fabricated by placing a first-layer self-supporting film adjacent to a cathode coating layer and a second-layer self-supporting film adjacent to a solid electrolyte layer. The thickness of the first-layer self-supporting film was 2.5 μm. The thickness of the second-layer self-supporting film was 2.5 μm.

[0149] Evaluation Example: Charge / Discharge Test and Life Characteristics Evaluation

[0150] The charge-discharge characteristics of the all-solid-state batteries prepared in Examples 1 to 6 and Comparative Example 1 were evaluated by the following charge-discharge test.

[0151] The charge and discharge test was performed by placing the all-solid-state battery in a constant temperature bath at 45°C. Charging was carried out in CC mode. The battery was charged at 0.05 C until the voltage reached 2.8 V, and discharge was carried out in CC mode at 0.05 C until it reached 1.0 V.

[0152] The discharge capacity of the first cycle was set as the standard capacity. The standard capacity is expressed as the specific capacity in Table 1 below. The initial efficiency is expressed by Equation 1 below.

[0153] <Mathematical Formula 1>

[0154] Initial efficiency [%] = [1st cycle discharge capacity / 1st cycle charge capacity] × 100

[0155] The cycles after the second cycle were charged and discharged under the same conditions as the first cycle. The SOH was measured after each cycle, and the charge-discharge test was repeated until the SOH reached 80%. The number of cycles in which the SOH reached 80% is indicated as the number of cycles in Table 1 below.

[0156] The high-rate characteristics of the all-solid-state batteries prepared in Examples 1 to 6 and Comparative Example 1 were evaluated by the following high-rate charge / discharge test.

[0157] The high-rate charge / discharge test was performed by placing the all-solid-state battery in a constant temperature bath at 45°C. Charging was carried out in CC mode. The battery was charged at 2 C until the voltage reached 2.8 V, and discharge was carried out in CC mode at 1 C until it reached 1.0 V. The high-rate characteristic (%) was calculated by dividing the discharge capacity in the high-rate charge / discharge test by the charge capacity in the high-rate charge / discharge test to determine the percentage (%), and is shown in Table 1 below.

[0158] The results of the charge / discharge test are summarized in Table 1 below.

[0159] Initial Efficiency [%] Specific Capacity [mAh / g] Number of Cycles [cycles, @SOH = 80%] High Rate Characteristics [%] Example 1 8989524295 Example 2 9089324394.5 Example 3 89.589124294.3 Example 4 90.189724594.2 Example 5 91.290523992.5 Example 6 88.988830296 Comparative Example 1 (bare) 857501025

[0160] It was confirmed that Examples 1 to 6 had superior charge-discharge characteristics compared to Comparative Example 1. When comparing Example 5 with all other examples and Comparative Examples, it was confirmed that Example 5 had the best initial efficiency and capacity.

[0161] When comparing Example 6 with all other examples and comparative examples, it was confirmed that Example 6 had the best high rate characteristics and the number of cycles required to reduce SOH to 80%.

[0162] Although an exemplary embodiment has been described in detail above with reference to the attached drawings, the present creative idea is not limited to such examples. It is obvious that a person skilled in the art to which the present creative idea belongs can derive various variations or modifications within the scope of the technical idea described in the patent claims, and these also naturally fall within the technical scope of the present creative idea.

Claims

1. A positive electrode comprising a positive electrode active material layer; A cathode comprising a cathode current collector, a cathode coating layer on the cathode current collector, and a sulfur coating layer on the cathode coating layer; and It includes a solid electrolyte layer disposed between the positive active material layer and the sulfur coating layer; The above cathode coating layer comprises a metal carbon composite, and The above sulfur coating layer comprises sulfur-based materials, in an all-solid-state battery.

2. In Paragraph 1, The sulfur coating layer further comprises a first intermediate layer adjacent to the cathode coating layer, and The above-mentioned first intermediate layer further comprises a metal-carbon composite, an all-solid-state battery.

3. In Paragraph 1, The sulfur coating layer further comprises a second intermediate layer adjacent to the solid electrolyte layer, and The above second intermediate layer further comprises a solid electrolyte, in a solid-state battery.

4. In Paragraph 1, The above sulfur-based material comprises S (Sulfur), S8 (Octasulfur), H2S, Li3PO4, LiCl, Li2S, SO2, SO3, or a combination thereof, in an all-solid-state battery.

5. In Paragraph 4, The above sulfur-based material further comprises Li2S8, Li2S6, Li2S4, Li2S2, or a combination thereof, in an all-solid-state battery.

6. In Paragraph 1, The above metal-carbon composite is a composite of amorphous carbon and metal particles, and The above metal particles comprise gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), zinc (Zn), or a combination thereof, in an all-solid-state battery.

7. In Paragraph 1, The above solid electrolyte is a sulfide-based solid electrolyte, and The above sulfide-based solid electrolyte is Li 7-x PS 6-x Cl x (0≤x≤2), Li 7-x PS 6-x Br x (0≤x≤2), Li 7-x PS 6-x I x All-solid-state battery comprising (0≤x≤2) or a combination thereof.

8. In Paragraph 1, An all-solid-state battery in which the content of sulfur atoms (S) contained in the sulfur coating layer is 30 at% to 100 at% with respect to the total atomic content contained in the sulfur coating layer.

9. Anode comprising a positive active material layer; A cathode comprising a cathode current collector and a cathode coating layer on the cathode current collector; A solid electrolyte layer disposed between the anode and the cathode; and It includes a protective layer disposed between the above-mentioned cathode coating layer and the above-mentioned solid electrolyte layer; The above protective layer comprises a metal carbon composite, sulfur-based materials, and a solid electrolyte, in an all-solid-state battery.

10. In Paragraph 9, The above protective layer further includes a first protective layer adjacent to the cathode coating layer and a second protective layer adjacent to the solid electrolyte layer, and A solid-state battery in which the content (at%) of sulfur atoms (S) contained in the first protective layer is greater than the content (at%) of sulfur atoms (S) contained in the second protective layer.

11. In Paragraph 9, The above protective layer further includes a first protective layer adjacent to the cathode coating layer and a second protective layer adjacent to the solid electrolyte layer, and A solid-state battery in which the content (at%) of sulfur atoms (S) contained in the second protective layer is greater than the content (at%) of sulfur atoms (S) contained in the first protective layer.

12. In Paragraph 9, The above sulfur-based material comprises S (Sulfur), S8 (Octasulfur), H2S, Li3PO4, LiCl, Li2S, SO2, SO3, or a combination thereof, in an all-solid-state battery.

13. In Paragraph 12, The above sulfur-based material further comprises Li2S8, Li2S6, Li2S4, Li2S2, or a combination thereof, in an all-solid-state battery.

14. In Paragraph 9, The above metal-carbon composite is a composite of amorphous carbon and metal particles, and The above metal particles comprise gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), zinc (Zn), or a combination thereof, in an all-solid-state battery.

15. In Paragraph 9, The above solid electrolyte is a sulfide-based solid electrolyte, and The above sulfide-based solid electrolyte is Li 7-x PS 6-x Cl x (0≤x≤2), Li 7-x PS 6-x Br x (0≤x≤2), Li 7-x PS 6-x I x All-solid-state battery comprising (0≤x≤2) or a combination thereof.

16. In Paragraph 9, An all-solid-state battery in which the thickness of the protective layer is 30% or more of the thickness of the negative electrode coating layer.

17. Providing a positive electrode; Providing a cathode comprising a cathode current collector and a cathode coating layer on the cathode current collector; Providing a solid electrolyte layer between the anode and the cathode; and A method for manufacturing an all-solid-state battery, comprising forming a sulfur coating layer between the above-mentioned cathode and the above-mentioned solid electrolyte layer.

18. In Paragraph 17, Forming the above sulfur coating layer is: A method for manufacturing an all-solid-state battery, comprising forming a sulfur-based material on one surface of the above-mentioned negative electrode coating layer.

19. In Paragraph 17, Forming the above sulfur coating layer is: A method for manufacturing an all-solid-state battery, comprising forming a sulfur-based material on one surface of the solid electrolyte layer.

20. In Paragraph 17, Forming the above sulfur coating layer is: Preparing a free-standing membrane containing sulfur-based materials; and Comprising the above self-supporting membrane between the above cathode and the above solid electrolyte layer; Method for manufacturing an all-solid-state battery.

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