Negative electrode layer, electrode structure for all-solid-state battery comprising same, and all-solid-state battery comprising same

Abstract

The present invention relates to a negative electrode layer, an electrode structure for an all-solid-state battery comprising same, and an all-solid-state battery comprising same, and more particularly, comprises a negative electrode current collector and a coating layer on the negative electrode current collector, the coating layer comprising: nano-sized lithiophilic metal particles having a first average particle diameter; silicon particles having a second average particle diameter that is greater than the first average particle diameter; and a carbon-based material, wherein the capacity is 1000 mAh / g or less.

Description

A negative electrode layer, an electrode structure for an all-solid-state battery including the same, and an all-solid-state battery including the same

[0001] The present invention relates to a negative electrode layer, an electrode structure for an all-solid-state battery including the same, and an all-solid-state battery including the same.

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

[0003] Recently, all-solid-state batteries in which liquid electrolytes are replaced with solid electrolytes have been proposed. By not using flammable organic dispersion media, all-solid-state batteries can significantly reduce the likelihood of fire or explosion in the event of a short circuit. Therefore, these all-solid-state batteries can offer significantly higher safety compared to lithium-ion batteries that use liquid electrolytes.

[0004] The problem that the present invention aims to solve is to provide a negative electrode layer with improved lifespan characteristics, an electrode structure including the same, and an all-solid battery including the same.

[0005] A negative electrode layer according to one embodiment of the present invention comprises a negative electrode current collector and a coating layer on the negative electrode current collector, wherein the coating layer comprises: nano-sized lithium-affinity metal particles having a first average particle size; silicon particles having a second average particle size larger than the first average particle size; and a carbon-based material, and the capacity may be 1000 mAh / g or less.

[0006] An electrode structure for an all-solid-state battery according to one embodiment of the present invention comprises a negative electrode layer; and a solid electrolyte layer on the negative electrode layer, wherein the negative electrode layer may be the negative electrode layer for an all-solid-state battery described above.

[0007] An all-solid-state battery according to one embodiment of the present invention comprises a positive electrode layer; a negative electrode layer; and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, wherein the negative electrode layer may be the negative electrode layer for an all-solid-state battery described above.

[0008] A negative electrode layer according to one embodiment of the present invention, an electrode structure including the same, and an all-solid-state battery including the same can have excellent lifespan characteristics.

[0009] FIG. 1 is a cross-sectional view of an all-solid-state battery according to embodiments of the present invention.

[0010] FIG. 2 is a cross-sectional view of a cathode layer according to one embodiment of the present invention.

[0011] FIG. 3 is an enlarged view of a coating layer according to one embodiment of the present invention.

[0012] FIG. 4 is an enlarged view of a coating layer according to another embodiment of the present invention.

[0013] FIG. 5 is a cross-sectional view of a cathode layer according to another embodiment of the present invention.

[0014] In order to fully understand the structure and effects of the present invention, preferred embodiments of the present invention are described with reference to the attached drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms and various modifications can be made. The description of these embodiments is provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention.

[0015] In this specification, when a component is described as being on another component, it means that it may be formed directly on the other component or that a third component may be interposed between them. Additionally, in the drawings, the thicknesses of the components are exaggerated for the effective description of the technical content. Throughout the specification, parts indicated by the same reference numeral represent the same components.

[0016] The embodiments described herein will be described with reference to cross-sectional and / or plan views, which are exemplary illustrations of the invention. In the drawings, the thicknesses of films and regions are exaggerated for effective description of the technical content. Accordingly, the regions illustrated in the drawings are schematic in nature, and the shapes of the regions illustrated in the drawings are intended to illustrate specific forms of regions of the device and are not intended to limit the scope of the invention. Although terms such as first, second, third, etc., have been used to describe various components in the various embodiments of this specification, these components should not be limited by such terms. These terms are used merely to distinguish one component from another. The embodiments described and illustrated herein also include their complementary embodiments.

[0017] The terms used herein are for describing the embodiments and are not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated otherwise in the text. As used herein, 'comprises' and / or 'comprising' do not exclude the presence or addition of one or more other components to the mentioned components.

[0018] In this specification, "combination of these" may mean a mixture of components, a laminate, a composite, a copolymer, an alloy, a blend, and a reaction product, etc.

[0019] Unless otherwise defined in this specification, the particle size may be the average particle size. Additionally, the particle size refers to the average particle size (D50), which means the diameter of the particle whose cumulative volume in the particle size distribution is 50% by volume. The average particle size (D50) may be measured by methods widely known to those skilled in the art, for example, by measuring with a particle size analyzer, or by measuring with a transmission electron microscope (TEM) image or a scanning electron microscope (SEM) image. Alternatively, the average particle size (D50) value may be obtained by measuring using a measuring device utilizing dynamic light-scattering, performing data analysis to count the number of particles for each particle size range, and then calculating from this. Alternatively, it may be measured using a laser diffraction method. When measuring by laser diffraction, more specifically, after dispersing the particles to be measured in a dispersion medium, they are introduced into a commercially available laser diffraction particle size measuring device (e.g., Microtrac MT 3000) and irradiated with ultrasound of about 28 kHz at an output of 60 W, and then the average particle size (D50) at 50% of the particle size distribution in the measuring device can be calculated.

[0020] In this specification, each of the phrases such as “A or B”, “at least one of A and B”, “at least one of A or B”, “A, B or C”, “at least one of A, B and C”, and “at least one of A, B, or C” may include any one of the items listed together in the corresponding phrase, or all possible combinations thereof.

[0021]

[0022] FIG. 1 is a cross-sectional view of an all-solid-state battery (10) according to one embodiment of the present invention.

[0023] Referring to FIG. 1, an all-solid-state battery (10) according to one embodiment includes a positive electrode layer (100), a negative electrode layer (200) facing the positive electrode layer (100), and a solid electrolyte layer (300) disposed between the positive electrode layer (100) and the negative electrode layer (200). However, the all-solid-state battery (10) may further include an additional functional layer, such as an adhesion-enhancing layer, disposed between the positive electrode layer (100) and the solid electrolyte layer (300) or between the negative electrode layer (200) and the solid electrolyte layer (300).

[0024] An anode layer (100) of one embodiment includes an anode current collector (110) and an anode active material layer (120) disposed on the anode current collector (110). The anode active material layer (120) may include an anode active material, a solid electrolyte, a conductive material, and a binder.

[0025] 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, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), zinc (Zn), aluminum (Al), germanium (Ge), lithium (Li), or an alloy thereof.

[0026] Meanwhile, unlike as illustrated in FIG. 1, the positive current collector (110) may be omitted in one embodiment of the present invention. 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).

[0027] The cathode active material is a material capable of reversibly absorbing and desorbing lithium ions. The cathode active material may include, for example, lithium transition metal oxides such as lithium cobalt oxide (LCO), lithium nickel oxide, lithium nickel cobalt oxide, lithium nickel cobalt aluminum oxide (NCA), lithium nickel cobalt manganese oxide (NCM), lithium manganate, and lithium iron phosphate, as well as nickel sulfide, copper sulfide, lithium sulfide, iron oxide, or vanadium oxide, but is not necessarily limited to these. Each cathode active material may be a single material or a mixture of two or more materials.

[0028] Lithium transition metal oxides are, for example, Li a A 1-b B b D2(0.90≤a≤1, 0≤b≤0.5), Li a E 1-b B b O 2-c D c (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05), LiE 2-b B b O 4-c D c (0≤b≤0.5, 0≤c≤0.05), Li a Ni 1-b-c Co b B c D α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α<2), Li a Ni 1-b-c Co b B c O 2-α F α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α<2), Li a Ni 1-b-c Mn b B c D α(0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α≤2), Li a Nor 1-b-c Mn b B c O 2-α F α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α<2), Li a Nor b E c G d O2(0.90≤a≤1, 0≤b≤0.9, 0≤c≤0.5, 0.001≤d≤0.1), Li a Nor b Co c Mn d GeO2(0.90≤a≤1, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0.001≤e≤0.1), Li a NiG b O2(0.9≤a≤1, 0.001≤b≤0.1), Li a CoG b O2(0.90≤a≤1, 0.001≤b≤0.1), Li a MnG b O2(0.90≤a≤1, 0.001≤b≤0.1), Li a Mn2GbO4(0.90≤a≤1, 0.001≤b≤0.1), QO2, QS2, LiQS2, V2O5, LiV2O5, LiIO2, LiNiVO4, Li 3-f J2(PO4)3(0≤f≤2), Li 3-fIt is a compound represented by any one of Fe2(PO4)3 (0≤f≤2) or LiFePO4. In such compounds, the uppercase “A” is Ni, Co, Mn, or a combination thereof; the uppercase “B” is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element, or a combination thereof; the uppercase “D” is O, F, S, P, or a combination thereof; the uppercase “E” is Co, Mn, or a combination thereof; the uppercase “F” is F, S, P, or a combination thereof; the uppercase “G” is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; the uppercase “Q” is Ti, Mo, Mn, or a combination thereof; the uppercase “I” is Cr, V, Fe, Sc, Y, or a combination thereof; and the uppercase “J” is V, Cr, Mn, Co, Ni, Cu, or a combination thereof.

[0029] The cathode active material may include, for example, a lithium salt of a transition metal oxide having a layered rock salt type structure among the lithium transition metal oxides described above. The "layered rock salt type structure" is, for example, a cubic rock salt type structure. <111> It is a structure in which oxygen and metal atomic layers are alternately and regularly arranged in a specific direction, thereby forming a two-dimensional plane for each atomic layer. The "cubic rock salt type structure" represents a sodium chloride (NaCl) type structure, which is a type of crystal structure; specifically, it exhibits a structure in which face-centered cubic lattices (fcc) formed by cations and anions, respectively, are offset from each other by half the ridge of the unit lattice. Lithium transition metal oxides having such a layered rock salt type structure are, for example, LiNi x Co y Al z O2(NCA) or LiNi x Co y Mn zO2(NCM) (0 <x<1,0<y<1, 0<z<1, x+y+z=1) 등의 삼원계 리튬전이금속산화물일 수 있다. 양극활물질이 층상암염형 구조를 갖는 삼원계 리튬전이금속산화물을 포함하는 경우, 전고체 전지(10)의 에너지 밀도가 커지고 열안정성이 향상될 수 있다.

[0030] The aforementioned compound contained in the cathode active material may be covered by a coating layer (not shown). The cathode active material may also be a mixture of the aforementioned compound and the compound to which the coating layer is added. Meanwhile, the coating layer added to the surface of the cathode active material may include, for example, oxides, hydroxides, oxyhydroxides, oxycarbonates, or hydroxycarbonates of the following coating elements. The compounds forming this coating layer are amorphous or crystalline. The coating elements included in the coating layer may include Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or mixtures thereof. The coating layer may include, for example, Li2O-ZrO2 (LZO). The method for forming the coating layer is selected within a range that does not adversely affect the physical properties of the cathode active material. The method for forming the coating layer is, for example, spray coating or immersion.

[0031] When the positive electrode active material is a ternary lithium transition metal oxide such as NCA or NCM and contains nickel (Ni), the capacity density of the all-solid-state battery (10) is increased, and the metal leaching of the positive electrode active material in the charged state can be reduced. As a result, the cycle characteristics of the all-solid-state battery (10) in the charged state are improved. Meanwhile, “cycle characteristics” is a characteristic that indicates the degree of deterioration of the all-solid-state battery (10) due to charging and discharging of the all-solid-state battery (10). An all-solid-state battery (10) with high cycle characteristics has a small degree of deterioration due to charging and discharging, while an all-solid-state battery (10) with low cycle characteristics may have a large degree of deterioration due to charging and discharging.

[0032] The shape of the cathode active material may include particle shapes such as spheres or ellipsoids. The particle size and content of the cathode active material are not particularly limited.

[0033] 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, and 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), and Li 7-x PS 6-x I x It may include at least one selected from (0≤x≤2).

[0034] 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 xIt 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.

[0035] Alternatively, sulfide-based solid electrolytes are Li 7-a M a PS 6-c X c It 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 scandium (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.

[0036] 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.

[0037] The solid electrolyte included in the positive electrode active material layer (120) may have a smaller average particle size (D50) compared to the solid electrolyte included in the solid electrolyte layer (300). For example, the average particle size (D50) of the solid electrolyte included in the positive electrode active material layer (120) may be 90% or less, 80% or less, 70% or less, 60% or less, 50% or less, 40% or less, 30% or less, or 20% or less of the average particle size (D50) of the solid electrolyte included in the solid electrolyte layer (300). Meanwhile, the average particle size (D50) may be a median diameter measured using a laser particle size distribution meter.

[0038] The positive electrode active material layer (120) may 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 electrode active material and the solid electrolyte. The conductive material may include a carbon-based material. The conductive material may include, for example, one or more selected from graphite, carbon black, acetylene black, carbon nanofibers, and carbon nanotubes.

[0039] The positive active material layer (120) may further include a binder. The binder may include a material for bonding the positive active material, solid electrolyte, and conductive material included in the positive active material layer (120), and for improving the bonding strength with the positive current collector (110). The binder may include, for example, polyvinylidene fluoride, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, vinylidene fluoride / hexafluoropropylene copolymer, polyacrylonitrile, and polymethyl methacrylate.

[0040] Based on 100 parts by weight of the total positive active material, solid electrolyte, conductive material, and binder, the positive active material layer (120) may contain 75 parts by weight or more and 92 parts by weight or less of the positive active material. Based on 100 parts by weight of the total positive active material, solid electrolyte, conductive material, and binder, the positive active material layer (120) may contain 0.5 parts by weight or more and 1.5 parts by weight or less of the binder.

[0041] Based on 100 parts by weight of solid electrolyte, the positive active material layer (120) may contain 1 part by weight or more and 50 parts by weight or less of a conductive material. If the conductive material is included in the positive active material layer (120) in an amount less than 1 part by weight based on 100 parts by weight of solid electrolyte, the proportion of the conductive material decreases, and the electrical conductivity of the positive active material layer (120) may decrease. If the conductive material is included in the positive active material layer (120) in an amount exceeding 50 parts by weight based on 100 parts by weight of solid electrolyte, the proportion of the conductive material is excessively high, and a coating layer covering the surface of the solid electrolyte may not be properly formed.

[0042] The positive active material layer (120) may further include additives such as fillers, coating agents, dispersants, and ion conductivity aids in addition to the positive active material, solid electrolyte, conductive material, and binder described above.

[0043] The solid electrolyte layer (300) is disposed between the anode layer (100) and the cathode layer (200) and includes a sulfide-based solid electrolyte with excellent lithium ion conductivity characteristics. The solid electrolyte included in the solid electrolyte layer (300) 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 anode active material layer (120).

[0044] The solid electrolyte layer (300) of one embodiment may include a sulfide-based solid electrolyte. The sulfide-based solid electrolyte may be manufactured by processing starting materials, such as Li2S or P2S5, by a melt quenching method or a mechanical milling method. Additionally, heat treatment may be performed after such processing. The solid electrolyte may be amorphous, crystalline, or a mixture thereof. Furthermore, the solid electrolyte may include sulfur (S), phosphorus (P), and lithium (Li) as at least constituent elements among the sulfide-based solid electrolyte materials described above, for example. For example, the solid electrolyte may be a material containing Li2S-P2S5. When using a sulfide-based solid electrolyte material containing Li2S-P2S5 to form the solid electrolyte, the molar ratio of Li2S and P2S5 is, for example, in the range of Li2S : P2S5 = 50 : 50 to 90 : 10.

[0045] 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.

[0046] 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 scandium (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.

[0047] The density of the azyrodite-type solid electrolyte may be 1.5 g / cc to 2.0 g / cc. Since the azyrodite-type solid electrolyte has a density of 1.5 g / cc or higher, 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 is, for example, 15 GPa to 35 GPa.

[0048] The solid electrolyte layer (300) may further include a binder. The binder included in the solid electrolyte layer (300) is, for example, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, etc., but is not limited to these. 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) or the binder included in the coating layer (220).

[0049] The cathode layer (200) will be described in detail later with reference to FIGS. 2 and FIGS. 3.

[0050] Meanwhile, although not shown, a carbon layer may be further included to improve adhesion between the coating layer (220) and the solid electrolyte layer (300).

[0051]

[0052] cathode layer

[0053] FIG. 2 is a cross-sectional view of a cathode layer (200) according to embodiments of the present invention. FIG. 3 is an enlarged view of the M region of FIG. 2, intended to explain a coating layer (220).

[0054] Referring to FIG. 2, the cathode layer (200) includes a cathode current collector (210) and a coating layer (220) disposed on the cathode current collector (210).

[0055] The negative electrode current collector (210) may provide a reference surface on which the coating layer (220) is placed. The negative electrode 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 electrode current collector (210) may be, for example, copper (Cu), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), and nickel (Ni), but is not necessarily limited to these, and any material used as an electrode current collector is possible. The thickness of the negative electrode current collector (210) may be 1 to 20 μm, for example 5 to 15 μm, for example 7 to 10 μm.

[0056] 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. Meanwhile, in one embodiment, the negative current collector (210) may be omitted.

[0057] Meanwhile, although not shown, a carbon layer may be further included to improve adhesion between the coating layer (220) and the solid electrolyte layer (300).

[0058] The coating layer (220) can cause lithium metal to grow between the all-solid-state battery (10) and the negative current collector (210) during charging. Alternatively, the coating layer (220) can cause lithium metal to grow or form an alloy with lithium inside the all-solid-state battery (10) during charging. The coating layer (220) can serve as a protective layer for the lithium metal and simultaneously suppress the precipitation and growth of lithium dendrites.

[0059] The coating layer (220) may have a smaller thickness compared to the positive active material layer (120, see FIG. 1). The thickness of the 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 active material layer (120). The thickness of the coating layer (220) may be 1 μm to 20 μm. For example, the thickness of the coating layer (220) may be 1 μm or more, 2 μm or more, 3 μm or more, 5 μm or more, 7 μm or more, or 10 μm or more. For example, the thickness of the coating layer (220) may be 20 μm or less, 15 μm or less, or 10 μm or less. For example, the thickness of the coating layer (220) may be about 10 μm. If the thickness of the coating layer (220) is excessively thin, lithium dendrites formed between the coating layer (220) and the negative current collector (210) may cause the coating layer (220) to collapse, thereby degrading the cycle characteristics of the all-solid-state battery (10). If the thickness of the coating layer (220) is excessively increased, the energy density of the all-solid-state battery (10) decreases, and the internal resistance of the all-solid-state battery (10) due to the coating layer (220) increases, which may degrade the cycle characteristics of the all-solid-state battery (10).

[0060] Referring to FIG. 3, the coating layer (220) may include lithium-affinity metal particles (PTC1), silicon particles (PTC2), and carbon-based material (CBL).

[0061] The lithium-affinity metal particles (PTC1) may include a lithium-affinity metal. For example, the lithium-affinity metal particles (PTC1) may include at least one selected from the group consisting of gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), zinc (Zn), magnesium (Mg), indium (In), and zinc oxide (ZnO). For example, the lithium-affinity metal particles (PTC1) may form a lithium precipitate layer below the coating layer (220), that is, between the coating layer (220) and the negative current collector (210).

[0062] The characteristics of the lithium-affinity metal particles (PTC1) can be represented by Equation 1 below. Equation 1 represents the Gibbs formation energy of the chemical reaction between the lithium-affinity metal particles (PTC1) and molten lithium at 250°C.

[0063] [Equation 1]

[0064] △G=△H1 523.15K -T△S1 523.15K ≤ 0

[0065] In other words, the Gibbs free energy (△G) of the chemical reaction between the lithium-affinity metal particles (PTC1) and molten lithium at 250°C may be 0 kJ / mol or less. For example, the Gibbs free energy (△G) of the chemical reaction between the lithium-affinity metal particles (PTC1) and molten lithium at 250°C may be -1500 kJ / mol to 0 kJ / mol. Under the above conditions, the lithium-affinity metal particles (PTC1) may spontaneously form an alloy with lithium.

[0066] The lithium-affinity metal particles (PTC1) may be nanoparticles. The average particle size (A) of the lithium-affinity metal particles (PTC1) may be 5 nm to 500 nm. For example, the average particle size (A) of the lithium-affinity metal particles (PTC1) may be 5 nm to 80 nm, or 10 nm to 50 nm. As an example, the average particle size may refer to the diameter measured by randomly selecting about 100 lithium-affinity metal particles (PTC1) from an electron microscope image of the coating layer (220). As an example, the average particle size may be measured by a particle size analyzer. The average particle size may refer to the diameter of a particle in which the cumulative volume in the particle size distribution is 50 volume%. If the average particle size (A) of the lithium-affinity metal particles (PTC1) satisfies the range described above, a lithium precipitation layer can be formed substantially on the underside of the coating layer (220), and the lifespan of the all-solid-state battery can be increased.

[0067] The content (B) of the lithium-affinity metal particles (PTC1) may be 3% to 50% by weight relative to the total weight of the coating layer (220). For example, the content (B) of the lithium-affinity metal particles (PTC1) may be 10% to 30% by weight, 15% to 25% by weight, or 15% to 20% by weight relative to the total weight of the coating layer (220). If the content (B) of the lithium-affinity metal particles (PTC1) satisfies the range described above, a lithium precipitation layer can be substantially formed on the underside of the coating layer (220), and the lifespan of the all-solid-state battery can be increased.

[0068] The average particle size (C) of the silicon particles (PTC2) may be larger than the average particle size of the lithium-affinity metal particles (PTC1). The silicon particles (PTC2) may be micro-sized particles. The average particle size (C) of the silicon particles (PTC2) may be 1 µm to 10 µm. For example, the average particle size (C) of the silicon particles (PTC2) may be 1 µm to 5 µm, or 1 µm to 3 µm. As an example, the average particle size may refer to the diameter measured by randomly selecting about 100 silicon particles (PTC2) from an electron microscope image of the coating layer (220). As an example, the average particle size may be measured with a particle size analyzer. The average particle size may refer to the diameter of the particle whose cumulative volume in the particle size distribution is 50 volume%.

[0069] The ratio (C / A) of the average particle size of silicon particles (PTC2) to the average particle size of lithium-affinity metal particles (PTC1) may be 20 to 350. For example, the ratio (C / A) of the average particle size of silicon particles (PTC2) to the average particle size of lithium-affinity metal particles (PTC1) may be 20 to 200, or 30 to 100.

[0070] If the average particle size (C) of the silicon particle (PTC2) and the ratio (C / A) of the average particle size of the silicon particle (PTC2) to the average particle size of the lithium-affinity metal particle (PTC1) satisfy the range described above, then at least a portion of the surface of the silicon particle (PTC2) can react with lithium ions to form an alloy.

[0071] Additionally, if the average particle size of the silicon particles (PTC2) satisfies the range described above, the silicon particles (PTC2) may not substantially contribute to the capacity of the all-solid-state battery. Thus, in addition to forming an alloy with lithium on its surface, the silicon particles (PTC2) can help form a lithium precipitation layer beneath the coating layer (220). This allows the lifespan of the all-solid-state battery to be extended.

[0072] The content (D) of silicon particles (PTC2) may be 1% to 50% by weight relative to the total weight of the coating layer (220). For example, the content (D) of silicon particles (PTC2) may be 1% to 30% by weight, 1% to 25% by weight, 2% to 20% by weight, 2% to 15% by weight, 3% to 15% by weight, 4% to 10% by weight, or 4% to 7% by weight relative to the total weight of the coating layer (220). As an example, the content (D) of silicon particles (PTC2) may be less than the content (B) of lithium-affinity metal particles (PTC1).

[0073] The ratio (D / B) of the content of the silicon particles (PTC2) to the content of the lithium-affinity metal particles (PTC1) may be 0.1 to 0.9. For example, the ratio (D / B) of the content of the silicon particles (PTC2) to the content of the lithium-affinity metal particles (PTC1) may be 0.1 to 0.7, 0.1 to 0.5, or 0.2 to 0.4.

[0074] If the content (D) of the silicon particles (PTC2) and the ratio (D / B) of the content of the silicon particles (PTC2) to the content of the lithium-affinity metal particles (PTC1) satisfy the range described above, the silicon particles (PTC2) can help form a lithium precipitation layer on the underside of the coating layer (220) in addition to forming an alloy with lithium on its surface, thereby extending the lifespan of the all-solid-state battery.

[0075] The carbon-based material (CBL) may include at least one selected from the group consisting of carbon black, carbon nanotube, acetylene black, furnace black, ketjen black, and graphene. For example, the carbon-based material (CBL) may be carbon black.

[0076] The content of the carbonaceous material (CBL) may be the content excluding the total weight of the lithium-affinity metal particles (PTC1) and silicon particles (PTC2) from the total content of the coating layer (220).

[0077] For example, carbonaceous materials (CBL) have the D band (peak position: 1350±50 cm⁻¹) in the Raman spectrum obtained by Raman spectroscopy. -1 (near) and G-band (peak position: 1580±50cm) -1 It may have (near). In this specification, the D / G ratio may be defined as the ratio of the maximum peak intensity of the D band to the maximum peak intensity of the G band. The D / G ratio of the carbonaceous material (CBL) may be 1.5 or higher. For example, the D / G ratio of the carbonaceous material (CBL) may be 1.5 to 3.0.

[0078] For example, carbonaceous materials (CBL) may have a d002 value of 3.500 to 3.620 as a result of X-ray diffraction (XRD) analysis.

[0079] For example, when the carbon-based material (CBL) is an assembly, the particle size of the primary particles may be 10 nm to 200 nm, and the particle size of the secondary particles may be 1 µm to 20 µm.

[0080] For example, the particle size of the primary particle may be 10 nm or more, 20 nm or more, 30 nm or more, 40 nm or more, 50 nm or more, 60 nm or more, 70 nm or more, 80 nm or more, or 90 nm or more, and may be 200 nm, 100 nm or less, 90 nm or less, 80 nm or less, 70 nm or less, 60 nm or less, 50 nm or less, 40 nm or less, or 30 nm or less.

[0081] For example, the particle size of the secondary particle may be 1㎛ or more, 3㎛ or more, 5㎛ or more, 7㎛ or more, 10㎛ or more, or 15㎛ or more, and may be 20㎛ or less, 15㎛ or less, 10㎛ or less, 7㎛ or less, 5㎛ or less, or 3㎛ or less.

[0082] For example, the shape of the primary particle may be spherical, elliptical, plate-like, and a combination thereof. For another example, the shape of the primary particle may be spherical, elliptical, and a combination thereof.

[0083] For example, the circularity of a carbonaceous material (CBL) can be 0.8 to 1.0.

[0084] For example, the BET specific surface area of ​​a carbonaceous material (CBL) is 40 m² 2 / g to 90m 2 It can be / g.

[0085] The coating layer (220) may not substantially contain a solid electrolyte. The content of the solid electrolyte in the coating layer (220) may be 1% by weight or less relative to the total weight of the coating layer (220). The content of the solid electrolyte in the coating layer (220) may be less than the content of the solid electrolyte in the solid electrolyte layer (300).

[0086] Although not illustrated, the coating layer (220) may further include a binder. As an example, the binder may include butadiene-based rubber and a cellulose-based compound. When the binder includes butadiene-based rubber and a cellulose-based compound, excellent adhesion can be exhibited while improving the dispersibility of carbon-based materials and metal particles, and structural stability can be improved.

[0087] For example, butadiene-based rubber may include at least one selected from the group consisting of styrene butadiene rubber (SBR), nitrile butadiene rubber (NBR), acrylate butadiene rubber (ABR), methacrylate butadiene rubber, acrylonitrile-butadiene-styrene (ABS) rubber, and styrene-butadiene-styrene (SBS) rubber.

[0088] For example, the cellulose-based compound may be a carboxyalkyl cellulose, a salt thereof, or a combination thereof. The alkyl of the carboxyalkyl cellulose may be a lower alkyl, specifically a C1 to C6 alkyl, and may be a linear alkyl or a branched alkyl. The salt of the cellulose-based compound may be an alkali salt, specifically an alkali salt of Na, Li, or a combination thereof.

[0089]

[0090] In the embodiments described below, detailed descriptions of technical features that overlap with those previously described with reference to FIGS. 1 to 3 are omitted, and differences are described in detail. FIG. 4 is an enlarged view of the M region of FIG. 3, intended to explain a coating layer (220) according to another embodiment of the present invention. FIG. 5 is a cross-sectional view intended to explain a cathode layer (200') according to another embodiment of the present invention.

[0091] FIG. 4 is a drawing for explaining a coating layer (220) according to one embodiment during charging of an all-solid-state battery according to the present invention. Referring to FIG. 4, the coating layer (220) during charging of the all-solid-state battery may further include a first lithium deposition layer (LDL1) on the surface of silicon particles (PTC2). The first lithium deposition layer (LDL1) may be a layer formed by charging of the all-solid-state battery.

[0092] A first lithium deposition layer (LDL1) may be formed on the surface of a silicon particle (PTC2). The first lithium deposition layer (LDL1) may be formed on at least a portion of the surface of the silicon particle (PTC2). For example, the first lithium deposition layer (LDL1) may have an island shape. However, the first lithium deposition layer (LDL1) may not be visible in an image obtained through an electron microscope. For example, the first lithium deposition layer (LDL1) may be identified through the lithium (Li) content on the surface of the silicon particle (PTC2).

[0093] Since the silicon particles (PTC2) within the coating layer (220) are micro-sized particles and the coating layer (220) substantially does not contain a solid electrolyte, the silicon particles (PTC2) within the coating layer (220) may have high surface resistance. As a result, the silicon particles (PTC2) can form an alloy with lithium only on the surface. That is, the concentration of lithium on the surface of the silicon particles (PTC2) may be higher than the concentration of lithium inside the silicon particles (PTC2). For example, the first lithium deposition layer (LDL1) may include a lithium-silicon alloy (Li-Si alloy).

[0094] For example, since the lithium-silicon alloy (Li-Si alloy) formed on the surface of the silicon particle (PTC2) has a low energy barrier, lithium can be precipitated on the lithium-silicon alloy (Li-Si alloy). That is, the first lithium deposition layer (LDL1) may contain lithium (Li).

[0095] In other words, the first lithium deposition layer (LDL1) may include at least one of lithium (Li) and a lithium-silicon alloy (Li-Si alloy). For example, the first lithium deposition layer (LDL1) may include lithium (Li). For example, the first lithium deposition layer (LDL1) may include a lithium-silicon alloy (Li-Si alloy). For example, the first lithium deposition layer (LDL1) may include lithium (Li) and a lithium-silicon alloy (Li-Si alloy).

[0096] FIG. 5 is a diagram illustrating a negative electrode layer (200') according to one embodiment during charging of an all-solid-state battery according to the present invention. Referring to FIG. 5, the negative electrode layer (200') during charging of the all-solid-state battery may further include a second lithium deposition layer (LDL2). The second lithium deposition layer (LDL2) may be a layer formed by charging of the all-solid-state battery.

[0097] A second lithium deposition layer (LDL2) may be disposed between a negative electrode current collector (210) and a coating layer (220). The second lithium deposition layer (LDL2) may be disposed on the lower surface of the coating layer (220). That is, the coating layer (220) may allow lithium metal to grow between the all-solid-state battery (10) and the negative electrode current collector (210) during charging. Alternatively, the coating layer (220) may form an alloy with lithium or allow lithium metal to grow inside the all-solid-state battery (10) during charging. For example, the second lithium deposition layer (LDL2) may include an alloy of lithium and a lithium-affinity metal. The coating layer (220) may serve as a protective layer for lithium metal and simultaneously suppress the precipitation and growth of lithium dendrites.

[0098] For example, the thickness of the formed second lithium deposition layer (LDL2) may be 5 μm to 30 μm.

[0099] Although not illustrated, as another example, the negative electrode layer (200) during charging of the all-solid-state battery according to the present invention may include both the first lithium deposition layer (LDL1) of FIG. 4 and the second lithium deposition layer (LDL2) of FIG. 5.

[0100] Although not illustrated, in another embodiment of the present invention, the coating layer (220) may be provided in the form of an electrode structure for an all-solid-state battery. The electrode structure for an all-solid-state battery may include a negative electrode layer (200) and a solid electrolyte layer (300). That is, the electrode structure for an all-solid-state battery may include a negative electrode current collector (210), a coating layer (220), and a solid electrolyte layer (300). The electrode structure for an all-solid-state battery may be a negative electrode composite layer. The coating layer (220) may be disposed on the negative electrode current collector (210). The solid electrolyte layer (300) may be disposed on the coating layer (220).

[0101] For example, the coating layer (220) may substantially not contain a sulfide-based solid electrolyte. For example, the content of the sulfide-based solid electrolyte in the coating layer (220) may be 1% by weight or less relative to the total weight of the coating layer (220). For example, the coating layer (220) may not contain any sulfide-based solid electrolyte at all. The sulfide-based solid electrolyte may be omitted from the coating layer (220).

[0102] For example, the solid electrolyte layer (300) may include a sulfide-based solid electrolyte. For example, the content of the sulfide-based solid electrolyte in the solid electrolyte layer (300) may be 80% by weight or more relative to the total weight of the solid electrolyte layer (300). For example, the content of the sulfide-based solid electrolyte in the solid electrolyte layer (300) may be 80% to 100% by weight relative to the total weight of the solid electrolyte layer (300).

[0103] The content of the sulfide-based solid electrolyte in the solid electrolyte layer (300) may be greater than the content of the sulfide-based solid electrolyte in the coating layer (220). For example, the content of the sulfide-based solid electrolyte in the solid electrolyte layer (300) may be 100 times or more than the content of the sulfide-based solid electrolyte in the coating layer (220).

[0104]

[0105] The negative electrode layer (200) and the all-solid-state battery (10) including the coating layer (220) according to embodiments of the present invention may have the following characteristics.

[0106] The N / P ratio of the all-solid-state battery may be 0.3 or less. In the present invention, the N / P ratio may be defined as the ratio of the capacity of the negative electrode layer (200) to the capacity of the positive electrode layer (100). That is, the negative electrode layer (200) of the present invention may not substantially exhibit capacity.

[0107] For example, the capacity of the negative electrode layer (200) may be 1000 mAh / g or less. As an example, the capacity of the negative electrode layer (200) may be 0 mAh / g to 1000 mAh / g, 10 mAh / g to 1000 mAh / g, or 300 mAh / g to 1000 mAh / g. In other words, the negative electrode layer (200) may be formed so as not to have any capacity.

[0108] When charging the all-solid-state battery, the all-solid-state battery may include at least one of a first lithium deposition layer (LDL1) and a second lithium deposition layer (LDL2). For example, when charging the all-solid-state battery, the all-solid-state battery may include the first lithium deposition layer (LDL1) or the second lithium deposition layer (LDL2). For example, when charging the all-solid-state battery, the all-solid-state battery may include the first lithium deposition layer (LDL1) and the second lithium deposition layer (LDL2). By doing so, the all-solid-state battery may have a long lifespan. For example, when the all-solid-state battery is charged and discharged 100 times at a constant current of 0.33C, the capacity retention rate may be 80% or more.

[0109]

[0110] The present invention will be explained in more detail below through examples. However, these examples are intended to illustrate the invention and the scope of the invention is not limited to these examples.

[0111]

[0112] Example 1

[0113] As a negative electrode current collector, a nickel-coated Cu substrate with a thickness of 10 μm was prepared. As lithium-affinity metal particles, nano-sized Ag particles (average particle size = 30 nm) were prepared. As micro-sized silicon particles, Si particles with an average particle size of 1 μm were prepared.

[0114] A cathode slurry was prepared by mixing inorganic particles (Ag particles and silicon particles), a carbon-based material (carbon black, average particle size of primary particles = approximately 30 nm), a binder (CMC, SBR), and a solvent (distilled water). The weight ratio of inorganic particles (Ag particles and silicon particles) to carbon black in the cathode slurry was 25:75. The weight ratio of Ag particles to silicon particles was 20:5. The total weight of inorganic particles (Ag particles and silicon particles) and carbon black to the binder was 100:9 (weight ratio of CMC, SBR = 6:3). The cathode slurry was applied to a cathode current collector using a bar coater and dried in a convection oven at 80°C to produce a cathode layer including a cathode current collector and a coating layer.

[0115] In the fabricated coating layer, the ratio of the average particle size of silicon particles to the average particle size of Ag particles (C / A) was 33.3. In the fabricated coating layer, the weight ratio of silicon particles to Ag particles (D / B) was 0.25. The thickness of the coating layer was 10 μm, and the cathode layer was fabricated so that its capacity was 1000 mAh / g or less.

[0116]

[0117] Example 2

[0118] It was prepared in the same manner as Example 1, except that Si with an average particle size of 3 μm was used as the micro-sized silicon particles.

[0119] In the manufactured coating layer, the ratio of the average particle size of silicon particles to the average particle size of Ag particles (C / A) was 100.

[0120]

[0121] Example 3

[0122] It was prepared in the same manner as Example 1, except that Si with an average particle size of 5 μm was used as the micro-sized silicon particles.

[0123] In the manufactured coating layer, the ratio of the average particle size of silicon particles to the average particle size of Ag particles (C / A) was 167.

[0124]

[0125] Example 4

[0126] It was prepared in the same manner as Example 1, except that Si with an average particle size of 10 μm was used as the micro-sized silicon particles.

[0127] In the manufactured coating layer, the ratio of the average particle size of silicon particles to the average particle size of Ag particles (C / A) was 333.

[0128]

[0129] Comparative example

[0130] A coating layer was formed using a cathode slurry comprising lithium-affinity metal particles (Ag particles, average particle size = 30 nm), a conductive material (carbon black), a binder (CMC, SBR), and a solvent (distilled water), with silicon particles omitted. The weight ratio of Ag particles to carbon black in the cathode slurry was 25:75. The weight ratio of the total weight of Ag particles and carbon black to the binder was 100:9 (weight ratio of CMC, SBR = 6:3). Otherwise, it was prepared in the same manner as in Example 1.

[0131] In the coating layer of the manufactured cathode layer, the ratio of the average particle size of silicon particles to the average particle size of Ag particles (C / A) was 0.

[0132]

[0133] Manufacturing of the anode layer

[0134] An anode layer containing an anode active material layer on an anode current collector was prepared. An aluminum foil with a thickness of approximately 13 μm was prepared as the anode current collector. The anode active material layer contained NCM as the anode active material, Li6PS5Cl (D50 = 0.5 μm, crystalline), which is an argyrodite-type crystal, as the solid electrolyte, carbon nanotubes (CNT) as the conductive material, and polyvinylidene fluoride (PVDF) as the binder in a weight ratio of 85:13.5:0.5:1.0.

[0135]

[0136] Preparation of a solid electrolyte layer

[0137] An acrylic binder (SX-A334, Zeon Co., Ltd.) was added to octyl acetate to prepare a 4 wt% binder solution. The prepared acrylic binder solution was added to a Li6PS5Cl solid electrolyte (D50=3 μm, crystalline), which is an argyrodite-type crystal, and mixed using a Thinky mixer to prepare a slurry. The slurry contained 1.5 parts by weight of the acrylic binder per 98.5 parts by weight of the solid electrolyte. The prepared slurry was applied onto a nonwoven fabric using a bar coater and dried in a convection oven at 80°C for 10 minutes to obtain a laminate. The obtained laminate was vacuum dried at 70°C for 2 hours.

[0138]

[0139] Manufacturing of all-solid-state batteries

[0140] A laminate was prepared by placing a solid electrolyte layer between the anode layer and the cathode layer. An all-solid-state secondary battery was manufactured by applying a warm isostatic press (WIP) to the prepared laminate at 80°C at a pressure of 500 MPa for 30 minutes. The N / P ratio was manufactured to be 0.3 or less.

[0141]

[0142] Experimental Example: Life Evaluation of All-Solid State Batteries

[0143] The lifespan of all-solid-state batteries comprising a negative electrode layer according to Examples 1 to 4 and Comparative Example was evaluated. The lifespan evaluation was performed by placing the all-solid-state battery in a constant temperature chamber at 45°C. For the lifespan evaluation, the all-solid-state battery was first charged at a constant current of 0.1C until the voltage reached 4.25V, and then discharged at 0.1C until the voltage reached 2.5V, thereby performing an initial charge-discharge cycle. Subsequently, the all-solid-state battery was charged at a constant current of 0.33C until the voltage reached 4.25V at 45°C, and then discharged at 0.33C until the voltage reached 2.5V, repeating this process for 100 cycles. The lifespan characteristics are expressed as the capacity retention rate according to the following formula. The results are shown in Table 1 below.

[0144]

[0145] [ceremony]

[0146] Capacity Retention Rate (%) = (Discharge Capacity at 100 Cycles / Initial Discharge Capacity) × 100

[0147]

[0148] Classification Capacity Retention Rate (%) Example 192 Example 292 Example 390 Example 482 Comparative Example 75

[0149]

[0150] Referring to Table 1, it was confirmed that the all-solid-state battery containing the negative electrode layer according to Examples 1 to 4 has a longer lifespan than the all-solid-state battery containing the negative electrode layer according to the Comparative Example.

[0151]

[0152] Although embodiments of the present invention have been described above with reference to the attached drawings, the present invention may be implemented in other specific forms without altering its technical concept or essential features. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive.

Claims

1. A negative current collector, and a coating layer on the negative current collector, and The above coating layer is: Nano-sized lithium-affinity metal particles having a first average particle size; Silicon particles having a second average particle size larger than the first average particle size; and Includes carbonaceous materials, The capacity is 1000mAh / g or less, Negative electrode layer for all-solid-state batteries.

2. In Paragraph 1, The ratio of the second average particle size to the first average particle size is 20 to 350, Negative electrode layer for all-solid-state batteries.

3. In Paragraph 1, The first average particle size is 5 nm to 500 nm, and The above second average particle size is 1㎛ to 10㎛, Negative electrode layer for all-solid-state batteries.

4. In Paragraph 1, The weight ratio of the silicon particles to the lithium-affinity metal particles is 0.1 to 0.

9. Negative electrode layer for all-solid-state batteries.

5. In Paragraph 1, The content of the lithium-affinity metal particles is 3% to 50% by weight relative to the total weight of the coating layer, and The content of the silicon particles is 1% to 50% by weight relative to the total weight of the coating layer, Negative electrode layer for all-solid-state batteries.

6. In Paragraph 1, The above lithium-affinity metal comprises at least one selected from the group consisting of gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), zinc (Zn), magnesium (Mg), indium (In), and zinc oxide (ZnO). Negative electrode layer for all-solid-state batteries.

7. In Paragraph 1, The above carbon-based material comprises at least one selected from the group consisting of carbon black, carbon nanotubes, acetylene black, furnace black, Ketchen black, and graphene. Negative electrode layer for all-solid-state batteries.

8. In Paragraph 1, The above coating layer is one in which the sulfide-based solid electrolyte is omitted, Negative electrode layer for all-solid-state batteries.

9. In Paragraph 1, The above coating layer further comprises a binder, and The above binder comprises butadiene-based rubber and a cellulose-based compound, Negative electrode layer for all-solid-state batteries.

10. In Paragraph 1, The thickness of the coating layer is 1㎛ to 20㎛, Negative electrode layer for all-solid-state batteries.

11. In Paragraph 1, The above coating layer is, The first lithium deposition layer on the surface of the silicon particles is further included, The first lithium deposition layer comprises at least one of lithium and a lithium-silicon alloy. Negative electrode layer for all-solid-state batteries.

12. In Paragraph 1, The above cathode layer is, It further includes a second lithium deposition layer disposed between the above-mentioned negative current collector and the above-mentioned coating layer, and The thickness of the second lithium deposition layer is 5㎛ to 30㎛, Negative electrode layer for all-solid-state batteries.

13. A cathode layer and a solid electrolyte layer on the cathode layer, wherein The above negative electrode layer is a negative electrode layer for an all-solid-state battery as described in claim 1, Electrode structure for all-solid-state batteries.

14. In Paragraph 13, The content of the sulfide-based solid electrolyte in the solid electrolyte layer is greater than the content of the sulfide-based solid electrolyte in the coating layer of the cathode layer. Electrode structure for all-solid-state batteries.

15. A positive electrode layer, a negative electrode layer, and a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, wherein The above negative electrode layer is a negative electrode layer for an all-solid-state battery as described in claim 1, All-solid-state battery.

16. In Paragraph 15, A solid-state battery having a capacity retention rate of 80% or more when subjected to 100 charge-discharge cycles at a constant current of 0.33C, All-solid-state battery.

17. In Paragraph 15, The content of the sulfide-based solid electrolyte in the solid electrolyte layer is greater than the content of the sulfide-based solid electrolyte in the coating layer of the cathode layer. All-solid-state battery.

18. In Paragraph 15, The ratio of the second average particle size to the first average particle size is 20 to 350, All-solid-state battery.

19. In Paragraph 15, The first average particle size of the lithium-affinity metal particles is 5 nm to 500 nm, All-solid-state battery.

20. In Paragraph 15, The weight ratio of the silicon particles to the lithium-affinity metal particles is 0.1 to 0.

9. All-solid-state battery.

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