Slurry for all-solid-state battery, positive electrode for all-solid-state battery, and all-solid-state battery

Abstract

The present invention relates to: a slurry for an all-solid-state battery; a positive electrode for an all-solid-state battery, the positive electrode being produced using the slurry; and an all-solid-state battery. More specifically, the slurry for an all-solid-state battery comprises a sulfide-based solid electrolyte, a non-aqueous solvent, and an additive, wherein the additive may include an amine-based polymer and a fatty acid compound.

Description

Slurry for all-solid-state batteries, cathode for all-solid-state batteries, and all-solid-state batteries

[0001] The present invention relates to a slurry for an all-solid-state battery, a positive electrode for an all-solid-state battery, and an all-solid-state battery.

[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 have been proposed in which the liquid electrolyte of lithium-ion batteries is replaced with a solid electrolyte. 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, such all-solid-state batteries can possess excellent safety.

[0004] The problem that the present invention aims to solve is to provide a slurry for an all-solid-state battery that has excellent dispersibility and phase stability and suppresses polysulfide leaching.

[0005] Another problem that the present invention aims to solve is to provide a positive electrode for an all-solid-state battery and an all-solid-state battery having excellent electrical performance and lifespan characteristics.

[0006] A slurry for an all-solid-state battery according to one embodiment of the present invention comprises a sulfide-based solid electrolyte, a non-aqueous solvent, and an additive, wherein the additive may include an amine-based polymer and a fatty acid compound.

[0007] A positive electrode for an all-solid-state battery according to one embodiment of the present invention comprises a positive electrode current collector and a positive electrode active material layer on the positive electrode current collector, wherein the positive electrode active material layer comprises a positive electrode active material, a sulfide-based solid electrolyte, and an additive, and the additive may comprise an amine-based polymer and a fatty acid compound.

[0008] According to one embodiment of the present invention, an all-solid-state battery comprises: a positive electrode including a positive current collector and a positive active material layer; a negative electrode including a negative current collector; and a solid electrolyte layer between the positive electrode and the negative electrode; wherein at least one of the positive active material layer or the solid electrolyte layer comprises a sulfide-based solid electrolyte and an additive, and the additive may comprise an amine-based polymer and a fatty acid compound.

[0009] The slurry for an all-solid-state battery according to the present invention has excellent dispersibility and phase stability, and polysulfide leaching can be suppressed. The anode or solid electrolyte layer prepared with the all-solid-state battery slurry can have excellent electrical properties and excellent lifespan characteristics.

[0010] FIG. 1 is a schematic diagram of a slurry for an all-solid-state battery according to an embodiment of the present invention.

[0011] FIG. 2 is a schematic diagram of a slurry for an all-solid-state battery according to a comparative example of the present invention.

[0012] FIG. 3 is a cross-sectional view of an all-solid-state battery according to one embodiment of the present invention.

[0013] FIG. 4 is a cross-sectional view of the enlarged region M of FIG. 3, intended to explain the positive active material layer (120) according to an embodiment of the present invention.

[0014] FIG. 5 is a cross-sectional view of the N region of FIG. 3 enlarged to explain a solid electrolyte layer (300) according to an embodiment of the present invention.

[0015] FIG. 6 is a plan view of an all-solid-state battery according to embodiments of the present invention.

[0016] Figure 7a is a cross-sectional view along the line A-A' of Figure 6.

[0017] Figure 7b is a cross-sectional view along the line B-B' of Figure 6.

[0018] FIG. 8 is a cross-sectional view along line A-A' of FIG. 6, intended to illustrate an all-solid-state battery according to another embodiment of the present invention.

[0019] FIGS. 9a and FIGS. 9b each show the results of the solubility evaluation of a mixed solution according to the reference examples of the present invention.

[0020] FIGS. 10a and FIGS. 10b each show the results of evaluating the solvent elution stability of a solid electrolyte solution according to the manufacturing examples of the present invention.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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 scanning electron microscope images. 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.

[0028] In one embodiment, the average particle size in this specification may refer to the diameter measured by randomly selecting about 100 particles from an electron microscope image. Alternatively, the average particle size in this specification may refer to the diameter of a particle that has a cumulative volume of 50% in the particle size distribution, which can be measured by a particle size analyzer.

[0029]

[0030] Slurry (SLL) for all-solid-state batteries

[0031] FIG. 1 is a schematic diagram of a slurry for an all-solid-state battery according to embodiments of the present invention. Referring to FIG. 1, the all-solid-state battery slurry (SSL) according to embodiments of the present invention may comprise a sulfide-based solid electrolyte (SSE), a non-aqueous solvent (NAS), and an additive (ADT). The additive (ADT) may comprise an amine-based polymer (PAP) and a fatty acid compound (FAC).

[0032] In this specification, the term "all-solid-state battery slurry (SSL)" may mean a slurry containing a solid electrolyte (SSE). The term "all-solid-state battery slurry (SSL)" may mean a solid electrolyte slurry for manufacturing a solid electrolyte layer or a positive electrode active material slurry for manufacturing a positive electrode active material layer.

[0033] Sulfide-based solid electrolytes (SSE) are, 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), 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 (SSE) 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.

[0035] Alternatively, sulfide-based solid electrolytes (SSE) are Li 7-a-c M1 a PS 6-c M2 c It may be an argyrodite-type compound containing (0≤a≤2, 0≤c≤2). Here, M2 may be F, Br, Cl, or a combination thereof. M1 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. there is.

[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 (SSE) may be, for example, 15 GPa to 35 GPa.

[0037] The non-aqueous solvent (NAS) may be a non-polar organic solvent or a weakly polar organic solvent that has low reactivity with the sulfide-based solid electrolyte (SSE). The non-aqueous solvent (NAS) may include, for example, at least one of xylene, benzene, toluene, pentane, hexane, octyl acetate, nonyl acetate, isobutyl isobutyrate (IBIB), diisopropylbenzene (DIPB), or a combination thereof. Diisopropylbenzene (DIPB) may be, for example, 1,2-diisopropylbenzene (1,2-DIPB), 1,3-diisopropylbenzene (1,3-DIPB), or 1,4-diisopropylbenzene (1,4-DIPB).

[0038] The additive (ADT) may include an amine-based polymer (PAP) and a fatty acid compound (FAC). The amine-based polymer (PAP) may include, for example, polyethyleneimine (PEI), polyvinylamine (PVAm), polyallylamine (PAAm), polypropyleneimine (PPI), polyamideamine (PAMAM), polyamidoimine (PAI), or at least one of a combination thereof.

[0039] The fatty acid compound (FAC) may include, but is not limited to, at least one of oleic acid, palmitoleic acid, cis-heptadecenoic acid, vaccenic acid, elaidic acid, linolenic acid, arachidonic acid, eicosanoic acid, erucic acid, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), nervonic acid, stearic acid, palmitic acid, arachidic acid, behenic acid, lignoceric acid, or a combination thereof. In one embodiment, the fatty acid compound (FAC) may include at least one of oleic acid, stearic acid, palmitic acid, linolenic acid, or a combination thereof. For example, the fatty acid compound (FAC) may include oleic acid or stearic acid.

[0040] When chemically reactive sulfide-based solid electrolytes (SSE) are exposed to a solvent (NAS), the sulfides can decompose to form polysulfides. The formed polysulfides can alter the surface charge of solid particles within a solid-state battery slurry (SLL) and increase the ion concentration of the slurry (SLL), thereby reducing the repulsion between particles. As a result, aggregation and / or sedimentation of solid particles may occur within the slurry (SLL). This can reduce the uniformity of the slurry (SLL), leading to problems with non-uniform film formation during the coating process.

[0041] Polysulfides can create abnormal interphases on the surface of solid electrolyte particles (SSE) or at the interface between the electrode and the solid electrolyte layer. These interfaces often have low ionic conductivity and electrical insulation, which can cause a decrease in battery output and electrochemical performance.

[0042] In addition, polysulfides can cause side reactions with sulfide-based solid electrolytes (SSE) and / or cathode active materials. If polysulfides cause side reactions with sulfide-based solid electrolytes (SSE), the structure of the electrolyte may be damaged, leading to a decrease in the ionic conductivity of the solid electrolyte (SSE). If polysulfides cause side reactions with cathode active materials, the structure of the cathode active material may be damaged, which may result in a decrease in the cathode's capacity and charge / discharge efficiency.

[0043] According to embodiments of the present invention, an amine-based polymer (PAP) can prevent the diffusion of polysulfides within a slurry (SLL) by scavenging polysulfides, and can improve the uniformity and phase stability of the slurry for all-solid-state batteries. An amine-based polymer (PAP) containing amine groups can effectively adsorb or capture polysulfides by forming an electrostatic interaction with negatively charged polysulfides. Furthermore, hydrogen bonding or weak covalent bonding can be formed between the amine groups and the polysulfides, allowing the amine-based polymer (PAP) to more effectively immobilize the polysulfides.

[0044] When polysulfides are adsorbed and immobilized by an amine-based polymer (PAP), the diffusion of polysulfides to the surface of the solid electrolyte (SSE) or to the interface between the solid electrolyte layer and the electrode can be prevented. As a result, irreversible reactions or abnormal interphase formation at the surface of the solid electrolyte (SLL) or the interface between the solid electrolyte layer and the electrode can be reduced, and the output and electrochemical performance of the battery can be improved.

[0045] In addition, when polysulfides are adsorbed by an amine-based polymer (PAP), side reactions between the polysulfides and the sulfide-based solid electrolyte (SLL) and / or between the polysulfides and the positive electrode active material can be suppressed. When side reactions are suppressed, the ionic conductivity of the solid electrolyte layer is improved, and the capacity and charge / discharge characteristics of the positive electrode can be improved.

[0046] However, amine-based polymers (PAP) may not dissolve well in non-polar or non-polar solvents. Referring to FIG. 2, which shows a slurry (SLL) for an all-solid-state battery according to a comparative example of the present invention, if the slurry (SLL) for an all-solid-state battery does not contain a fatty acid compound (FAC) and contains only an amine-based polymer (PAP), the amine-based polymer (PAP) may not dissolve well in the solvent (NAS) and may exist in an agglomerate or cluster state. This is because amine-based polymers (PAP) having polar functional groups generally do not dissolve well in non-polar or low-polar organic solvents.

[0047] Fatty acid compounds (FACs) can play a role in improving the solubility of amine polymers (PAPs) in solvents (NAS). Specifically, fatty acid compounds (FACs) can improve the solvent affinity of amine polymers (PAPs) through physical or chemical interactions with them. Fatty acid compounds (FACs) are weakly acidic compounds containing -COOH groups and can form ion pairs or complexes with the amine groups (-NH2) of amine polymers (PAPs) through hydrogen bonding or acid-base reactions. In this process, the lipophilic hydrocarbon chains of the fatty acid (FAC) are introduced into the structure of the amine polymer (PAPs) or adsorbed onto the surface of the amine polymer (PAPs), thereby reducing the overall polarity of the amine polymer (PAPs). This polarity-regulating effect can improve the solubility of amine polymers (PAPs) in non-polar or low-polarity solvents.

[0048] Referring again to FIG. 1, the slurry (SSL) for an all-solid-state battery according to embodiments of the present invention may include both an amine-based polymer (PAP) and a fatty acid compound (FAC) as additives (ADT). The amine-based polymer (PAP) can be evenly dissolved in the solvent (NAS) through interaction with the fatty acid compound (FAC) and effectively adsorb polysulfides.

[0049] In the slurry (SLL) for an all-solid-state battery according to the embodiments of the present invention, the amine-based polymer (PAP) and the fatty acid compound (FAC) may be mixed such that the molar ratio of the amine groups in the amine-based polymer (PAP) to the fatty acid compound (FAC) is 1:0.005 to 1:0.5, 1:0.007 to 1:0.3, or 1:0.007 to 1:0.1. The number of moles of amine groups in the amine-based polymer (PAP) can be calculated by multiplying the number of moles of the amine-based polymer (PAP) by the number of amine groups (e.g., the number of repeating units) contained per mole of the amine-based polymer (PAP). If the content of the fatty acid compound (FAC) relative to the amine groups is too small or too large, the interaction between the fatty acid compound (FAC) and the amine-based polymer (PAP) may not be sufficient, making it difficult to expect an improvement in solubility. If the molar ratio of the amine group and the fatty acid compound (FAC) satisfies the range described above, the additive (ADT) can be sufficiently dissolved in a non-polar or low-polarity solvent.

[0050] In the slurry (SLL) for an all-solid-state battery according to the embodiments of the present invention, the weight ratio of the sulfide-based solid electrolyte (SSE) to the additive (ADT) may be 100:0.1 to 100:10, or 100:0.5 to 100:5. If the content of the additive (ADT) is too low, the additive (ADT) may not be able to sufficiently scavenge the polysulfide. If the content of the additive (ADT) is too high, the additive (ADT) may act as a resistance, thereby degrading the performance of the anode or solid electrolyte layer. If the content of the additive (ADT) satisfies the range described above, the additive (ADT) can effectively adsorb the polysulfide without degrading the performance of the anode or solid electrolyte layer.

[0051] The slurry (SSL) for an all-solid-state battery may further include a binder. The binder can bind solid electrolyte particles (SSE) together or bind solid electrolyte particles (SSE) together with positive electrode active material particles. The binder can improve the bonding strength between the solid electrolyte layer and the positive electrode active material layer, or between the positive electrode active material layer and the positive electrode current collector.

[0052] The binder is not particularly limited as long as it can be dissolved in the aforementioned solvent (NAS), and may include, for example, fluorine-based binders, rubber-based binders, acrylic-based binders, etc. The binder may include, for example, polyvinylidenefluoride (PVdF), polyvinylidene fluoride / hexafluoropropylene copolymer (PVdF-HFP), styrene-butadiene rubber (SBR), nitrile butadiene rubber (NBR), polyacrylonitrile (PAN), polymethyl methacrylate (PMMA), polymethyl acrylate (PMA), polyethyl acrylate (PEA), polybutyl acrylate, polyacrylic acid (PAA), or at least one combination thereof.

[0053] FIG. 3 is a cross-sectional view of an all-solid-state battery according to one embodiment of the present invention. Hereinafter, an all-solid-state battery according to embodiments of the present invention will be described in more detail with reference to FIG. 3.

[0054] Referring to FIG. 3, an all-solid-state battery according to one embodiment may include 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 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).

[0055]

[0056] positive electrode (100)

[0057] The positive layer (100) may include a positive current collector (110) and a positive active material layer (120) disposed on the positive current collector (110).

[0058] 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.

[0059] Meanwhile, unlike as illustrated in FIG. 3, 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).

[0060] FIG. 4 is a cross-sectional view of the enlarged region M of FIG. 3, intended to illustrate a positive active material layer (120) according to embodiments of the present invention. Referring to FIG. 4, the positive active material layer (120) may include a positive active material (CAM), a sulfide-based solid electrolyte (SSE1), and an additive (ADT1). The additive (ADT1) may include an amine-based polymer (PAP1) and a fatty acid compound (FAC1). The positive active material layer (120) according to embodiments of the present invention may be manufactured using the all-solid-state battery slurry (SLL) described above.

[0061] The cathode active material (CAM) may include a material capable of reversibly absorbing and desorbing lithium ions. The cathode active material (CAM) 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.

[0062] 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), Lia Nor 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 Nor 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 Nor 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.

[0063] The positive active material (CAM) 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, for example, LiNi x Co y Al z O2(NCA) or LiNi x Co y Mnz O2(NCM) (0 <x<1,0<y<1, 0<z<1, x+y+z=1) 등의 삼원계 리튬전이금속산화물일 수 있다. 양극활물질(121)이 층상암염형 구조를 갖는 삼원계 리튬전이금속산화물을 포함하는 경우, 전고체 전지의 에너지 밀도가 커지고 열안정성이 향상될 수 있다.

[0064] The aforementioned compound contained in the positive electrode active material (CAM) may be covered by a coating layer (not shown). The positive electrode active material (CAM) may also be used as 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 positive electrode 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 positive electrode active material. The method for forming the coating layer is, for example, spray coating or immersion.

[0065] When the positive electrode active material (CAM) contains nickel (Ni) as a ternary lithium transition metal oxide such as NCA or NCM, for example, the capacity density of the all-solid-state battery is increased, and the metal leaching of the positive electrode active material (120) in the charged state can be reduced. As a result, the cycle characteristics of the all-solid-state battery in the charged state are improved. Meanwhile, “cycle characteristics” is a characteristic that indicates the degree of degradation of the all-solid-state battery due to charging and discharging; an all-solid-state battery with high cycle characteristics has a small degree of degradation due to charging and discharging, while an all-solid-state battery with low cycle characteristics may have a large degree of degradation due to charging and discharging.

[0066] The shape of the positive active material (CAM) may include particle shapes such as spheres or ellipsoids. The particle size and content of the positive active material (CAM) are not particularly limited. For example, the content of the positive active material (CAM) may be 80 parts by weight or more and 92 parts by weight or less based on 100 parts by weight of the positive active material layer (120).

[0067] The positive active material layer (120) may include a solid electrolyte. The solid electrolyte in the positive active material layer (120) may include a sulfide-based solid electrolyte (SSE1) with excellent lithium ion conductivity. The sulfide-based solid electrolyte (SSE1) may be the same as or different from the sulfide-based solid electrolyte (SSE) included in the all-solid-state battery slurry (SLL) described above. Alternatively, the sulfide-based solid electrolyte (SSE1) in the positive active material layer (120) may be the same as the solid electrolyte (SSE2) included in the solid electrolyte layer (300) described later.

[0068] For example, sulfide-based solid electrolytes (SSE1) are 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.

[0069] Alternatively, the sulfide-based solid electrolyte (SSE1) is Li 7-a-c M1 a PS 6-c M2 cIt may be an argyrodite-type compound containing (0≤a≤2, 0≤c≤2). Here, M2 may be F, Br, Cl, or a combination thereof. M1 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. there is.

[0070] The sulfide-based solid electrolyte (SSE1) included in the positive electrode active material layer (120) may have a smaller average particle size (D50) compared to the sulfide-based solid electrolyte (SSE2) included in the solid electrolyte layer (300) to be described later. For example, the average particle size (D50) of the sulfide-based solid electrolyte (SSE1) 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 sulfide-based solid electrolyte (SSE2) included in the solid electrolyte layer (300). Meanwhile, the average particle size (D50) may be the median diameter measured using a laser particle size distribution meter.

[0071] The additive (ADT1) of the positive active material layer (120) may be the same as or different from the additive (ADT) included in the all-solid-state battery slurry (SLL) described above.

[0072] The additive (ADT1) may include an amine-based polymer (PAP1) and a fatty acid compound (FAC1). The amine-based polymer (PAP1) may include, for example, polyethyleneimine (PEI), polyvinylamine (PVAm), polyallylamine (PAAm), polypropyleneimine (PPI), polyamideamine (PAMAM), polyamidoimine (PAI), or at least one of a combination thereof.

[0073] The fatty acid compound (FAC1) may include at least one of oleic acid, stearic acid, palmitic acid, linolenic acid, or a combination thereof, but is not limited thereto. The fatty acid compound (FAC1) may include, for example, at least one of oleic acid and stearic acid.

[0074] The amine-based polymer (PAP1) can adsorb polysulfides generated from the sulfide-based solid electrolyte (SSE1) within the anode active material slurry, thereby preventing the diffusion of polysulfides within the slurry and improving the uniformity and phase stability of the slurry.

[0075] In addition, the amine-based polymer (PAP1) can prevent polysulfide from diffusing within the positive electrode active material layer (120) and suppress side reactions between the polysulfide and the sulfide-based solid electrolyte (SSE1) and the positive electrode active material (CAM). This can improve the capacity, charge / discharge characteristics, and ion conductivity of the positive electrode (100).

[0076] The fatty acid compound (FAC1) can improve the solubility of the amine-based polymer (PAP1) in the solvent, thereby allowing the amine-based polymer (PAP1) to be evenly dispersed in the solvent during the anode active material slurry stage. As a result, the fatty acid compound (FAC1) can improve the dispersibility of the anode active material slurry and allow the anode active material layer (120) to be formed uniformly.

[0077] In the positive electrode active material layer (120), the amine-based polymer (PAP1) and the fatty acid compound (FAC1) can be mixed such that the molar ratio of the amine groups in the amine-based polymer (PAP1) to the fatty acid compound (FAC1) is 1:0.005 to 1:0.5, 1:0.007 to 1:0.3, or 1:0.007 to 1:0.1. If the molar ratio of the amine groups to the fatty acid compound (FAC1) satisfies the range described above, the positive electrode can have a uniform composition and excellent electrical characteristics.

[0078] In the positive electrode active material layer (120), the amine-based polymer (PAP1) and the fatty acid compound (FAC1) can each be detected through FT-IR spectroscopy (Fourier-Transform Infrared Spectroscopy), Raman spectroscopy, TOF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry) analysis, or GC-MS (Gas Chromatography-Mass Spectrometry).

[0079] In one embodiment, a sample taken from the positive active material layer (120) is analyzed by FT-IR to obtain a characteristic peak of an amine-based polymer (e.g., 3300–3500 cm⁻¹). -1 NH stretching vibration in the range and 1000~1350 cm -1 Amine-based polymers are detected by identifying CN stretching vibrations in the region, etc., and characteristic peaks of fatty acid compounds (e.g., 1700–1725 cm⁻¹) -1 C=O stretching vibration in the region and 2500-3300 cm-1 Fatty acid compounds can be detected by confirming the OH stretching vibrations of the region.

[0080] In another embodiment, a sample taken from the positive active material layer (120) is analyzed by Raman spectroscopy to obtain a characteristic peak of the amine-based polymer (e.g., 1200–1350 cm⁻¹). -1 CN stretching vibration in the area and 1500~1650 cm -1 The presence of amine-based polymers is confirmed by identifying NH bending vibrations in the region, etc., and characteristic peaks of fatty acid compounds (e.g., 1650–1750 cm⁻¹) -1 C=O stretching vibration in the region and 2800-3000 cm -1 The presence of fatty acid compounds can be confirmed by verifying the CH stretching vibrations of the region.

[0081] In another example, CH2NH2 analyzed via TOF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry). + , C2H6N + , NH4 + By confirming characteristic ion signals such as those of the above, the presence of amine-based polymers was confirmed, and RCOO - , CH3COO - The presence of fatty acid compounds can be confirmed by verifying characteristic ion signals such as those mentioned above.

[0082] The positive active material layer (120) may further include a binder. The type of binder is not particularly limited and may include, for example, polyvinylidenefluoride (PVdF), vinylidene fluoride / hexafluoropropylene copolymer (PVdF-HFP), styrene-butadiene rubber (SBR), nitrile butadiene rubber (NBR), polyacrylonitrile (PAN), polymethyl methacrylate (PMMA), polymethyl acrylate (PMA), polyethyl acrylate (PEA), polybutyl acrylate, polyacrylic acid (PAA), or at least one combination thereof.

[0083] The positive active material layer (120) may further include a conductive material. The conductive material may have conductivity without causing chemical changes in the unit cell (CEL), thereby increasing the conductivity of the positive active material (CAM) and the solid electrolyte (SSE1). 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.

[0084] Based on 100 parts by weight of the total positive active material (CAM), solid electrolyte (SSE1), additive (ADT1), conductive material, and binder, the positive active material layer (120) may contain 80 parts by weight or more and 92 parts by weight or less of the positive active material (CAM). Based on 100 parts by weight of the total positive active material (CAM), solid electrolyte (SSE1), additive (ADT1), 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.

[0085] Based on 100 parts by weight of solid electrolyte (SSE1), 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 (SSE1), 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 (SSE1), the proportion of the conductive material is excessively high, and a coating layer covering the surface of the solid electrolyte (SSE1) may not be properly formed.

[0086] Based on 100 parts by weight of solid electrolyte (SSE1), the positive active material layer (120) may contain an additive (ADT1) in an amount of 0.1 parts by weight or more and 10 parts by weight or less, or 0.5 parts by weight or less and 5 parts by weight or less. If the content of the additive (ADT1) is too small, the additive (ADT1) may not be able to sufficiently scavenge polysulfides. If the content of the additive (ADT1) is too large, the additive (ADT1) may act as a resistance, thereby degrading the performance of the positive electrode (100). If the content of the additive (ADT1) satisfies the range described above, the additive (ADT1) can effectively adsorb polysulfides without degrading the performance of the positive electrode (100).

[0087] The positive active material layer (120) may further include, in addition to the positive active material (CAM), sulfide-based solid electrolyte (SSE1), additive (ADT1), binder, and conductive material described above, for example, a filler, a coating agent, a dispersant, an ion conductivity aid, etc.

[0088]

[0089] cathode layer (200)

[0090] Referring to FIG. 3, the cathode layer (200) may include a cathode current collector (210) and a coating layer (220) disposed on the cathode current collector (210).

[0091] The negative electrode current collector (210) may provide a reference surface on which the negative electrode active material layer (220) is disposed. 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.

[0092] 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.

[0093] The negative electrode layer (200) may include a negative electrode current collector (210) and a coating layer (220) on the negative electrode current collector (210). 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. For example, the negative electrode current collector (210) may include at least one of copper (Cu), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), or an alloy thereof. The thickness of the negative electrode current collector (210) may be 1 μm to 20 μm, more specifically 5 μm to 15 μm, and more specifically 7 μm to 10 μm.

[0094] 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) may, for example, have a plate-like or foil-like shape. Meanwhile, in one embodiment, the negative current collector (210) may be omitted.

[0095] The coating layer (220) can allow lithium metal to grow between the unit cell and the negative current collector (210) 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.

[0096] The coating layer (220) may include metal and carbon. For example, the coating layer (220) may include at least one metal selected from the group consisting of gold (Au), platinum (Pt), palladium (Pd), silicon (Si), silver (Ag), aluminum (Al), bismuth (Bi), tin (Sn), and zinc (Zn). The coating layer (220) may include at least one carbon selected from the group consisting of carbon black, acetylene black, furnace black, ketjen black, and graphene. In one embodiment, the coating layer (220) may include a mixture of carbon black and silver (Ag).

[0097] The coating layer (220) may further include other additives in addition to metal and carbon. The coating layer (220) may further include at least one additive selected from the group consisting of, for example, binders, fillers, coating agents, dispersants, and ion-conducting aids.

[0098] The coating layer (220) may have a smaller thickness compared to the positive active material layer (120). 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, for example, 1 µm to 20 µm, 2 µm to 10 µm, or 3 µm to 7 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 collapse the coating layer (220), thereby degrading the cycle characteristics of the all-solid-state battery. If the thickness of the coating layer (220) is excessively increased, the energy density of the all-solid-state battery decreases, and the internal resistance of the all-solid-state battery due to the coating layer (220) increases, thereby degrading the cycle characteristics of the cell. 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).

[0099]

[0100] solid electrolyte layer (300)

[0101] A solid electrolyte layer (300) may be provided between the anode layer (100) and the cathode layer (200). FIG. 5 is a cross-sectional view of the N region of FIG. 3, enlarged, to illustrate a solid electrolyte layer (300) according to embodiments of the present invention. Referring to FIG. 5, the solid electrolyte layer (300) according to embodiments of the present invention may include a sulfide-based solid electrolyte (SSE2) and an additive (ADT2). The solid electrolyte layer (300) according to embodiments of the present invention may be manufactured using the all-solid-state battery slurry (SLL) described above.

[0102] The sulfide-based solid electrolyte (SSE2) in the solid electrolyte layer (300) may be the same as the solid electrolyte (SSE) included in the aforementioned all-solid-state battery slurry (SLL). For example, the sulfide-based solid electrolyte (SSE2) is Li 7-x PS 6-xCl 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.

[0103] Alternatively, the sulfide-based solid electrolyte (SSE2) is Li 7-a-c M1 a PS 6-c M2 c It may be an argyrodite-type compound containing (0≤a≤2, 0≤c≤2). Here, M2 may be F, Br, Cl, or a combination thereof. M1 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. there is.

[0104] The content of the sulfide-based solid electrolyte (SSE2) in the solid electrolyte layer (300) may be 90 parts by weight or more per 100 parts by weight of the solid electrolyte layer.

[0105] The additive (ADT2) of the solid electrolyte layer (300) may be the same as or different from the additive (ADT) included in the all-solid-state battery slurry (SLL) described above. The additive (ADT2) may include an amine-based polymer (PAP2) and a fatty acid compound (FAC2).

[0106] The amine-based polymer (PAP2) may include, for example, polyethyleneimine (PEI), polyvinylamine (PVAm), polyallylamine (PAAm), polypropyleneimine (PPI), polyamideamine (PAMAM), polyamidoimine (PAI), or at least one of a combination thereof.

[0107] The fatty acid compound (FAC2) may include at least one of oleic acid, stearic acid, palmitic acid, linolenic acid, or a combination thereof, but is not limited thereto. The fatty acid compound (FAC2) may include, for example, at least one of oleic acid and stearic acid.

[0108] In the amine-based polymer (PAP2) solid electrolyte slurry, polysulfides generated from the sulfide-based solid electrolyte (SSE2) are adsorbed to prevent the diffusion of polysulfides within the slurry and improve the uniformity and phase stability of the slurry.

[0109] In addition, the amine-based polymer (PAP2) can prevent polysulfide from diffusing within the solid electrolyte layer (300) and suppress side reactions between the sulfide-based solid electrolyte (SSE2) and the polysulfide. This can improve the ionic conductivity of the solid electrolyte layer (300).

[0110] The fatty acid compound (FAC2) can improve the solubility of the amine-based polymer (PAP2) in the solvent, thereby allowing the amine-based polymer (PAP2) to be evenly dispersed in the solvent during the solid electrolyte slurry stage. As a result, the fatty acid compound (FAC2) can improve the dispersibility of the solid electrolyte slurry and allow the solid electrolyte layer (300) to be formed uniformly.

[0111] In the solid electrolyte layer (300), the amine-based polymer (PAP2) and the fatty acid compound (FAC2) can be mixed such that the molar ratio of the amine groups in the amine-based polymer (PAP2) to the fatty acid compound (FAC2) is 1:0.005 to 1:0.5, 1:0.007 to 1:0.3, or 1:0.007 to 1:0.1. If the molar ratio of the amine groups to the fatty acid compound (FAC2) satisfies the range described above, the solid electrolyte layer (300) can have a uniform composition and excellent electrical properties.

[0112] In the solid electrolyte layer (300), the amine-based polymer (PAP2) and the fatty acid compound (FAC2) can each be detected through FT-IR spectroscopy (Fourier-Transform Infrared Spectroscopy), Raman spectroscopy, TOF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry) analysis, or GC-MS (Gas Chromatography-Mass Spectrometry).

[0113] In one embodiment, a sample taken from the solid electrolyte layer (300) is analyzed by FT-IR to obtain characteristic peaks of amine-based polymers (e.g., 3300–3500 cm⁻¹). -1 NH stretching vibration in the range and 1000~1350 cm -1 Amine-based polymers are detected by identifying CN stretching vibrations in the region, etc., and characteristic peaks of fatty acid compounds (e.g., 1700–1725 cm⁻¹) -1C=O stretching vibration in the region and 2500-3300 cm -1 Fatty acid compounds can be detected by confirming the OH stretching vibrations of the region.

[0114] In another embodiment, a sample taken from the solid electrolyte layer (300) is analyzed by Raman spectroscopy to obtain a characteristic peak of the amine-based polymer (e.g., 1200–1350 cm⁻¹). -1 CN stretching vibration in the area and 1500~1650 cm -1 The presence of amine-based polymers is confirmed by identifying NH bending vibrations in the region, etc., and characteristic peaks of fatty acid compounds (e.g., 1650–1750 cm⁻¹) -1 C=O stretching vibration in the region and 2800-3000 cm -1 The presence of fatty acid compounds can be confirmed by verifying the CH stretching vibrations of the region.

[0115] In another example, CH2NH2 analyzed via TOF-SIMS (Time-of-Flight Secondary Ion Mass Spectrometry). + , C2H6N + , NH4 + By confirming characteristic ion signals such as those of the above, the presence of amine-based polymers was confirmed, and RCOO - , CH3COO - The presence of fatty acid compounds can be confirmed by verifying characteristic ion signals such as those mentioned above.

[0116] Based on 100 parts by weight of solid electrolyte (SSE2), the solid electrolyte layer (300) may contain an additive (ADT2) in an amount of 0.1 parts by weight or more and 10 parts by weight or 0.5 parts by weight or more and 5 parts by weight or less. If the content of the additive (ADT2) is too small, the additive (ADT2) may not be able to sufficiently scavenge polysulfides. If the content of the additive (ADT2) is too large, the additive (ADT2) may act as a resistance, thereby degrading the performance of the solid electrolyte layer (300). If the content of the additive (ADT2) satisfies the range described above, the additive (ADT2) can effectively adsorb polysulfides without degrading the performance of the solid electrolyte layer (300).

[0117] The solid electrolyte layer (300) may further include a binder. The type of binder is not particularly limited and may include, for example, polyvinylidenefluoride (PVdF), vinylidene fluoride / hexafluoropropylene copolymer (PVdF-HFP), styrene-butadiene rubber (SBR), nitrile butadiene rubber (NBR), polyacrylonitrile (PAN), polymethyl methacrylate (PMMA), polymethyl acrylate (PMA), polyethyl acrylate (PEA), polybutyl acrylate, polyacrylic acid (PAA), or at least one combination thereof. The content of the binder in the solid electrolyte layer (300) may be 10 parts by weight or less per 100 parts by weight of the solid electrolyte layer.

[0118]

[0119] In the embodiments described below, detailed descriptions of technical features that overlap with those previously described with reference to FIGS. 1 to 5 are omitted, and differences are described in detail.

[0120] FIG. 6 is a plan view of an all-solid-state battery according to embodiments of the present invention. FIG. 7a is a cross-sectional view along line A-A' of FIG. 6. FIG. 7b is a cross-sectional view along line B-B' of FIG. 6.

[0121] Referring to FIGS. 6, FIGS. 7a and FIGS. 7b, the solid electrolyte layer (300) may include a first solid electrolyte layer (310) and a second solid electrolyte layer (320). The first solid electrolyte layer (310) may be adjacent to the anode layer (100), and the second solid electrolyte layer (320) may be adjacent to the cathode layer (200).

[0122] The first solid electrolyte layer (310) may include the first solid electrolyte. The second solid electrolyte layer (320) may include the second solid electrolyte. Each of the first and second solid electrolytes may be the same as the sulfide-based solid electrolyte (SSE2) described above with reference to FIG. 5. For example, each of the first and second solid electrolytes may have a particle shape such as a sphere or an ellipsoid.

[0123] Each of the first solid electrolyte layer (310) and the second solid electrolyte layer (320) may further include a binder. The binder included in the first and second solid electrolyte layers (310, 320) may include, for example, at least one of polyvinylidenefluoride (PVdF), vinylidene fluoride / hexafluoropropylene copolymer (PVdF-HFP), styrene-butadiene rubber (SBR), nitrile butadiene rubber (NBR), polyacrylonitrile (PAN), polymethyl methacrylate (PMMA), polymethyl acrylate (PMA), polyethyl acrylate (PEA), polybutyl acrylate, polyacrylic acid (PAA), or a combination thereof. there is.

[0124] Each of the first solid electrolyte layer (310) and the second solid electrolyte layer (320) may further include an additive. The additive may be the same as the additive (ADT2) described above with reference to FIG. 5. Specifically, the additive may include an amine-based polymer and a fatty acid compound.

[0125] The second solid electrolyte can come into direct contact with the coating layer (220). By doing so, the second solid electrolyte can suppress lithium dendrites formed between the coating layer (220) and the negative electrode current collector (210). The second solid electrolyte can effectively suppress negative electrode side reactions. This can improve the cell performance of the all-solid-state battery according to the present invention.

[0126] The first solid electrolyte layer (310) may have a first thickness (TK1), and the second solid electrolyte layer (320) may have a second thickness (TK2). The first thickness (TK1) and the second thickness (TK2) may be the same or different from each other. In one embodiment, the first thickness (TK1) may be greater than the second thickness (TK2). For example, the first thickness (TK1) may be 1.1 to 5 times the second thickness (TK2).

[0127] Referring again to FIGS. 6, FIGS. 7a, and FIGS. 7b, the anode layer (100) and the first solid electrolyte layer (310) can form an anode composite layer (CSH). The cathode layer (200) and the second solid electrolyte layer (320) can form a cathode composite layer (ASH). The anode composite layer (CSH) can be laminated on the cathode composite layer (ASH).

[0128] The area of ​​the cathode composite layer (ASH) and the area of ​​the anode composite layer (CSH) may differ from each other. Specifically, the area of ​​the cathode composite layer (ASH) may be larger than the area of ​​the anode composite layer (CSH). The anode composite layer (CSH) may completely overlap within the cathode composite layer (ASH).

[0129] In one embodiment of the present invention, the first solid electrolyte layer (310) may have substantially the same area as the anode layer (100). The second solid electrolyte layer (320) may have substantially the same area as the cathode layer (200).

[0130] Specifically, the positive electrode composite layer (CSH) may have a first width (WI1) in a first direction (D1). The negative electrode composite layer (ASH) may have a second width (WI2) in a first direction (D1). The first width (WI1) may be smaller than the second width (WI2). The positive electrode composite layer (CSH) may have a third width (WI3) in a second direction (D2). The negative electrode composite layer (ASH) may have a fourth width (WI4) in a second direction (D2). The third width (WI3) may be smaller than the fourth width (WI4).

[0131] A unit cell (CEL) according to the present embodiment can be manufactured by forming a negative composite layer (ASH) on a first carrier film, forming an anode composite layer (CSH) on a second carrier film, and then laminating the negative composite layer (ASH) and the anode composite layer (CSH).

[0132] The unit cell (CEL) according to the present embodiment may further include a gasket (GSK). The gasket (GSK) may be provided to surround the positive composite layer (CSH). The gasket (GSK) may fill the step difference on the side of the unit cell (CEL) caused by the difference in area between the negative composite layer (ASH) and the positive composite layer (CSH). The gasket (GSK) may surround the four sides of the positive composite layer (CSH). For example, the thickness of the gasket (GSK) may be substantially the same as or smaller than the thickness of the positive composite layer (CSH). In one embodiment, the positive current collector (110) may be provided at a position higher than the gasket (GSK).

[0133] The positive current collector (110) may include a positive tab (CTB). The positive tab (CTB) may be a protruding area of ​​the positive current collector (110). In one embodiment, the positive tab (CTB) may protrude in a second direction (D2).

[0134] The negative current collector (210) may include a negative tab (ATB). The negative tab (ATB) may be a protruding area of ​​the negative current collector (210). In one embodiment, the negative tab (ATB) may protrude in the opposite direction of the second direction (D2).

[0135]

[0136] FIG. 8 is a cross-sectional view along line A-A' of FIG. 6, illustrating an all-solid-state battery according to another embodiment of the present invention. Referring to FIG. 8, the negative electrode layer (200) of a unit cell (CEL) may further include a lithium metal layer (400) between a negative electrode current collector (210) and a coating layer (220). The thickness of the lithium metal layer (400) may increase further during charging of the unit cell (CEL). The coating layer (220) serves as a protective layer for the lithium metal layer (400) and, at the same time, can suppress the growth of lithium dendrites from the lithium metal layer (400).

[0137] The lithium metal layer (400) may include lithium or a lithium alloy. Since the lithium metal layer (400) is a metal layer containing lithium, it may function as, for example, a lithium reservoir. The lithium alloy may be, for example, a Li-Al alloy, a Li-Sn alloy, a Li-In alloy, a Li-Ag alloy, a Li-Au alloy, a Li-Zn alloy, a Li-Ge alloy, a Li-Si alloy, 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 (400) may be composed of one of these alloys or lithium, or may be composed of various types of alloys. The lithium metal layer (400) may be, for example, a plated layer. The lithium metal layer (400) may be deposited between the coating layer (220) and the negative current collector (210) during the charging process of the unit cell (CEL), for example.

[0138] In another embodiment of the present invention, a lithium metal layer (400) within the negative electrode (200) may be provided, for example, between the negative electrode current collector (210) and the coating layer (220) before the assembly of the unit cell (CEL). When the lithium metal layer (400) is placed between the negative electrode current collector (210) and the coating layer (220) before the assembly of the all-solid-state battery, the lithium metal layer (400) 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 coating layer (220) before the assembly of the unit cell (CEL).

[0139] When a lithium metal layer (400) is deposited by charging after the assembly of the unit cell (CEL), the energy density of the unit cell (CEL) can be increased because the lithium metal layer is not included during the assembly of the unit cell (CEL). When charging the unit cell (CEL), it can be charged beyond the charging capacity of the coating layer (220). That is, the coating layer (220) is overcharged. Lithium can be absorbed in the coating layer (220) at the beginning of charging. When charging beyond the capacity of the coating layer (220), lithium can be deposited, for example, between the negative electrode coating layer (220) and the negative electrode current collector (210). A metal layer (400) can be formed by the deposited lithium.

[0140] The lithium metal layer (400) can be composed mainly of lithium (i.e., metallic lithium). During discharge, the lithium in the lithium metal layer (400) can be ionized and move to the positive electrode (100). In other words, lithium can be used as a negative electrode active material in the unit cell (CEL). In addition, since the coating layer (220) covers the lithium metal layer (400), the coating layer (220) can protect the lithium metal layer (400) and simultaneously suppress the precipitation growth of lithium dendrites. Therefore, the coating layer (220) can suppress short circuits and capacity degradation of the unit cell (CEL) and improve the cycle characteristics of the unit cell (CEL).

[0141] When a lithium metal layer (400) is formed by charging after assembly of a unit cell (CEL), the negative electrode (200), that is, the negative electrode current collector (210) and the 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 unit cell (CEL).

[0142] The lithium metal layer (400) may have a fifth width (WI5) in the first direction (D1). The fifth width (WI5) may be equal to or greater than the first width (WI1). The fifth width (WI5) may be equal to or smaller than the second width (WI2). For example, the fifth width (WI5) may be greater than the first width (WI1) and smaller than the second width (WI2).

[0143]

[0144] The embodiments of the present invention will be described in more detail below. However, the following embodiments are provided merely to aid in understanding the present invention and do not limit the scope of the present invention.

[0145]

[0146] Reference Example 1-1

[0147] Octyl acetate was prepared as a solvent. Polyethyleneimine (PEI) and stearic acid (SA) with a molecular weight of approximately 800 g / mol were prepared as additives.

[0148] A mixed solution was prepared by adding 2g of polyethyleneimine and 0.1g of stearic acid to 2g of octyl acetate solvent.

[0149] The weight ratio of amine-based polymers and fatty acids and the molar ratio of amine groups to fatty acids in the prepared mixed solution are shown in Table 1 below.

[0150] The molar ratio of amine groups to fatty acids can be calculated by calculating the number of moles of the polymer using the total mass and average molecular weight of the amine-based polymer, multiplying this by the number of amine groups contained per mole of polymer (e.g., number of repeating units) to obtain the total number of moles of amine groups, and comparing this with the number of moles of fatty acid compounds. For example, in the case of polyethyleneimine with an average molecular weight of about 800 g / mol, it can be assumed that it contains about 18.6 moles of amine groups per mole of polymer based on the molecular weight of the repeating unit -CH2CH2NH- (about 43.07 g / mol), and the number of moles of amine groups can be calculated from the input mass of the polymer. Meanwhile, the number of moles of fatty acids can be calculated by dividing the mass of the corresponding compound by its molecular weight, and finally, the molar ratio of amine groups to fatty acids can be determined from the ratio of the number of moles of amine groups to the number of moles of fatty acids.

[0151]

[0152] Reference Example 1-2

[0153] A mixed solution was prepared in the same manner as in Reference Example 1-1, except that 0.2 g of stearic acid was added. The weight ratio of amine-based polymers and fatty acids in the prepared mixed solution, and the molar ratio of amine groups to fatty acids, are shown in Table 1 below.

[0154]

[0155] Reference Example 1-3

[0156] A mixed solution was prepared in the same manner as in Reference Example 1-1, except that 0.5 g of stearic acid was added. The weight ratio of amine-based polymers and fatty acids in the prepared mixed solution, and the molar ratio of amine groups to fatty acids, are shown in Table 1 below.

[0157]

[0158] Reference Example 1-4

[0159] A mixed solution was prepared in the same manner as in Reference Example 1-1, except that 1.0 g of stearic acid was added. The weight ratio of amine-based polymers and fatty acids in the prepared mixed solution, and the molar ratio of amine groups to fatty acids, are shown in Table 1 below.

[0160]

[0161] Reference Example 1-5

[0162] A mixed solution was prepared in the same manner as in Reference Example 1-1, except that 2.0 g of stearic acid was added. The weight ratio of amine-based polymers and fatty acids in the prepared mixed solution, and the molar ratio of amine groups to fatty acids, are shown in Table 1 below.

[0163]

[0164] Reference Example 1-6

[0165] A mixed solution was prepared in the same manner as in Reference Example 1-1, except that 4.0 g of stearic acid was added. The weight ratio of amine-based polymers and fatty acids in the prepared mixed solution, and the molar ratio of amine groups to fatty acids, are shown in Table 1 below.

[0166]

[0167] Reference Example 2-1

[0168] A mixed solution was prepared in the same manner as in Reference Example 1-1, except that oleic acid (OA) was added instead of stearic acid as the fatty acid compound. The weight ratio of the amine-based polymer and the fatty acid in the prepared mixed solution, and the molar ratio of the amine group to the fatty acid are shown in Table 1 below.

[0169]

[0170] Reference Example 2-2

[0171] A mixed solution was prepared in the same manner as in Reference Example 2-1, except that 0.2 g of oleic acid was added. The weight ratio of amine-based polymers and fatty acids in the prepared mixed solution, and the molar ratio of amine groups to fatty acids, are shown in Table 1 below.

[0172]

[0173] Reference Example 2-3

[0174] A mixed solution was prepared in the same manner as in Reference Example 2-1, except that 0.5 g of oleic acid was added. The weight ratio of amine-based polymers and fatty acids in the prepared mixed solution, and the molar ratio of amine groups to fatty acids, are shown in Table 1 below.

[0175]

[0176] Reference Example 2-4

[0177] A mixed solution was prepared in the same manner as in Reference Example 2-1, except that 1.0 g of oleic acid was added. The weight ratio of amine-based polymers and fatty acids in the prepared mixed solution, and the molar ratio of amine groups to fatty acids, are shown in Table 1 below.

[0178]

[0179] Reference Example 2-5

[0180] A mixed solution was prepared in the same manner as in Reference Example 2-1, except that 2.0 g of oleic acid was added. The weight ratio of amine-based polymers and fatty acids in the prepared mixed solution, and the molar ratio of amine groups to fatty acids, are shown in Table 1 below.

[0181]

[0182] Reference Example 2-6

[0183] A mixed solution was prepared in the same manner as in Reference Example 2-1, except that 4.0 g of oleic acid was added. The weight ratio of amine-based polymers and fatty acids in the prepared mixed solution, and the molar ratio of amine groups to fatty acids, are shown in Table 1 below.

[0184]

[0185] Reference Example 3

[0186] A mixed solution was prepared by adding 2g of polyethyleneimine to 2g of octyl acetate solvent. That is, a mixed solution was prepared in the same manner as in Example 1-1, except that stearic acid was not added.

[0187]

[0188] Evaluation Example 1: Evaluation of Additive Solubility

[0189] The solubility of the mixed solution prepared according to the reference examples was evaluated by stirring it at room temperature for 60 minutes. Some of the results are shown in Table 1, Figure 9a, and Figure 9b below.

[0190]

[0191] Additive Weight Ratio Molar Ratio Amine-based Polymer Fatty Acid Amine-based Fatty Acid Reference Example 1-1 PEI / SA 10.05 10.008 Clear Solution Reference Example 1-2 PEI / SA 10.1 10.015 Clear Solution Reference Example 1-3 PEI / SA 10.25 10.038 Turbid Solution Reference Example 1-4 PEI / SA 10.5 10.076 Turbid Solution Reference Example 1-5 PEI / SA 11 10.151 Turbid Solution Reference Example 1-6 PEI / SA 12 10.303 Turbid Solution Reference Example 2-1 PEI / OA 10.05 10.008 Turbid Solution Reference Example 2-2 PEI / OA 10.1 10.015 Turbid Solution Reference Example 2-3 PEI / OA 10.25 10.038 Clear Solution 2-4PEI / OA1 0.5 10.076 Clear solution Reference Example 2-5PEI / OA11 10.153 Presence of insoluble gel Reference Example 2-6PEI / OA12 10.306 Presence of insoluble gel Reference Example 3PEI ---- Almost insoluble

[0192] Referring to Table 1 and Figure 9, it can be seen that the mixed solutions of Reference Examples 1-1, 1-2, 2-3, and 2-4 are in a transparent solution state, indicating that the additives are almost completely dissolved.

[0193] Preparation Example 1-1

[0194] As a sulfide-based solid electrolyte, a azirodite-based solid electrolyte (Li6PS5Cl) powder was prepared. As an additive, a mixture of polyethyleneimine (PEI) with a molecular weight of about 800 g / mol and stearic acid (SA) was prepared (the mixing ratio of PEI to SA was 1:0.1 by weight).

[0195] A solid electrolyte solution was prepared by adding the above sulfide-based solid electrolyte and the above additive to an octyl acetate solvent in a weight ratio of 100:0.6 and mixing.

[0196]

[0197] Preparation Example 1-2

[0198] A solid electrolyte solution was prepared in the same manner as in Preparation Example 1-1, except that the sulfide-based solid electrolyte and the additive were mixed in a weight ratio of 100:1.2.

[0199]

[0200] Preparation Examples 1-3

[0201] A solid electrolyte solution was prepared in the same manner as in Preparation Example 1-1, except that the sulfide-based solid electrolyte and the additive were mixed in a weight ratio of 100:2.4.

[0202]

[0203] Preparation Example 2-1

[0204] As a sulfide-based solid electrolyte, a azirodite-based solid electrolyte (Li6PS5Cl) powder was prepared. As an additive, a mixture of polyethyleneimine (PEI) with a molecular weight of about 800 g / mol and oleic acid (OA) was prepared (the mixing ratio of PEI to OA was 1:0.5 by weight).

[0205] A solid electrolyte solution was prepared by adding the above sulfide-based solid electrolyte and the above additive to an octyl acetate solvent in a weight ratio of 100:0.7 and mixing.

[0206]

[0207] Preparation Example 2-2

[0208] A solid electrolyte solution was prepared in the same manner as in Preparation Example 2-1, except that the sulfide-based solid electrolyte and the additive were mixed in a weight ratio of 100:1.4.

[0209]

[0210] Preparation Example 2-3

[0211] A solid electrolyte solution was prepared in the same manner as in Preparation Example 2-1, except that the sulfide-based solid electrolyte and the additive were mixed in a weight ratio of 100:2.8.

[0212]

[0213] Preparation Example 3

[0214] A solid electrolyte solution was prepared by adding only the sulfide-based solid electrolyte to the octyl acetate solvent, excluding additives.

[0215]

[0216] Evaluation Example 2: Evaluation of Solvent Elution Stability of Sulfide-Based Solid Electrolytes

[0217] The solvent elution stability of the sulfide-based solid electrolyte was evaluated by leaving the solid electrolyte solution prepared according to the preparation examples for at least 2 days without stirring, and the results are shown in FIG. 10a and FIG. 10b.

[0218] Referring to FIGS. 10a and 10b, it can be seen that the solid electrolyte solutions of Preparation Examples 1-1 to 1-3 and Preparation Examples 2-1 to 2-3 show less color change after being left for more than 2 days compared to immediately after preparation, when compared to the solid electrolyte solution of Preparation Example 3. In the case of Preparation Examples 1-3 and 2-3, the color of the solution hardly changes, confirming that polysulfide leaching was effectively suppressed.

[0219]

[0220] Example 1

[0221] (Preparation of cathode active material slurry)

[0222] LiNi as the positive active material 0.8 Co 0.1 Al 0.1O2 (NCA) powder was prepared as the sulfide-based solid electrolyte, and a azirodite-based solid electrolyte (Li6PS5Cl) powder was prepared as the sulfide-based solid electrolyte. Vinylidene fluoride / hexafluoropropylene copolymer (PVdF / HFP) was prepared as the binder, and carbon nanofiber (CNF) was prepared as the conductive material. As an additive, a mixture of polyethyleneimine (PEI) with a molecular weight of about 800 g / mol and stearic acid (SA) (the mixing ratio of PEI to SA was 1:0.1 by weight) was prepared.

[0223] A cathode active material slurry was prepared by mixing these materials in an octyl acetate solvent in a weight ratio of cathode active material : solid electrolyte : additive : conductive material : binder = 84.69 : 13 : 0.31 : 1 : 1.

[0224] (Anode manufacturing)

[0225] The above positive active material slurry was coated onto an aluminum positive current collector and dried at 130°C for at least 10 minutes to produce a positive electrode.

[0226] (Preparation of solid electrolyte layer)

[0227] A solid electrolyte slurry was prepared by adding an azirodite-based solid electrolyte (Li6PS5Cl) and a polyvinylidene fluoride (PVdF) binder solution to an octyl acetate solvent (the mixing ratio of the solid electrolyte to the binder was 98.7:1.3 by weight). The prepared solid electrolyte slurry was coated onto a release polytetrafluoroethylene film and dried at 60°C for at least 2 hours to prepare a solid electrolyte layer.

[0228] (Symmetric Coin Cell Manufacturing)

[0229] A symmetric coin cell was manufactured by applying the above-prepared anode equally as the working electrode and the counter electrode, and placing the above-prepared solid electrolyte layer between the two electrodes.

[0230]

[0231] Example 2

[0232] A mixture of polyethyleneimine (PEI) with a molecular weight of approximately 800 g / mol and oleic acid (OA) (the mixing ratio of PEI to OA was 1:0.5 by weight) was used as an additive when preparing the cathode active material slurry. The cathode active material slurry was prepared by mixing the cathode active material : solid electrolyte : additive : conductive material : binder in a weight ratio of 84.64 : 13 : 0.36 : 1 : 1 under octyl acetate solvent. Except for this, the cathode, solid electrolyte layer, and symmetric coil cell were prepared in the same manner as in Example 1.

[0233]

[0234] Comparative example

[0235] A positive electrode, a solid electrolyte layer, and a symmetric coil cell were prepared in the same manner as in Example 1, except that no additives were added when preparing the positive electrode active material slurry, and the positive electrode active material : solid electrolyte : conductive material : binder were mixed in a weight ratio of 85 : 13 : 1 : 1.

[0236]

[0237] Evaluation Example 3: Evaluation of Phase Stability of Anode Active Material Slurry

[0238] 10 ml of the cathode active material slurry prepared according to the examples and comparative examples was fed into an Anton Paar rheometer to measure the shear viscosity.

[0239] The shear viscosity (viscosity at a shear rate of 10 (1 / s)) of the cathode active material slurries of the examples and comparative examples at room temperature (20°C) was measured immediately after preparation of the slurry and after being left undisturbed for 1 day, respectively, and the results are shown in Table 2. The viscosity increase rate in Table 2 was calculated according to the following Equation 1.

[0240] <Equation 1>

[0241] Viscosity Increase Rate (%) = [(Shear Viscosity after 1 Day of Unstirred Standing - Shear Viscosity Immediately After Manufacturing) / Shear Viscosity Immediately After Manufacturing] X 100

[0242] Classification Additive Type Slurry Viscosity (mPa·s) Viscosity Increase Rate (%) Immediately After Preparation Unstirred 1 Day Example 1 PEI / SA 2,117 2,2446 Example 2 PEI / OA 2,325 2,3983 Comparative Example None 1,956 8,346 327

[0243] Referring to Table 2, it can be seen that the rate of change in viscosity after unstirred storage of the cathode active material slurry according to the examples is significantly smaller compared to the cathode active material slurry according to the comparative example.

[0244] Evaluation Example 4: Evaluation of Electrical Characteristics of the Anode

[0245] The ionic conductivity and electrical conductivity of the anode were evaluated using the symmetric coin cell prepared according to the examples and comparative examples in the following manner.

[0246] Electrochemical Impedance Spectroscopy (EIS) was performed on the symmetric coin cell. The EIS was conducted at an amplitude of approximately 10 mV, a frequency of 10 mHz to 1 MHz, in an air atmosphere at 45°C. The anode plate was a mixed conductor capable of the simultaneous transport of electrons and ions, allowing for the design of a corresponding equivalent circuit. A Nyquist plot was obtained through impedance analysis, and the ionic and electronic conductivity of the anode plate were isolated from it. The results are shown in Table 3.

[0247]

[0248] Classification Additive Type Ionic Conductivity (mS / cm) Electron Conductivity (mS / cm) Example 1 PEI / SA 0.03 5 0.65 Example 2 PEI / OA 0.04 2 0.57 Comparative Example None 0.02 7 0.43

[0249] Referring to Table 3, it can be seen that the anode according to the example has superior ionic conductivity and electronic conductivity compared to the anode according to the comparative example.

[0250] 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. Includes a sulfide-based solid electrolyte, a non-aqueous solvent, and additives, but, The above additive comprises amine-based polymers and fatty acid compounds, Slurry for all-solid-state batteries.

2. In Paragraph 1, The above amine-based polymer comprises at least one of polyethyleneimine (PEI), polyvinylamine (PVAm), polyallylamine (PAAm), polypropyleneimine (PPI), polyamideamine (PAMAM), polyamidoimine (PAI), or a combination thereof. Slurry for all-solid-state batteries.

3. In Paragraph 1, The above fatty acid compound comprises at least one of oleic acid, palmitoleic acid, cis-heptadecenoic acid, vaccenic acid, elaidic acid, linolenic acid, arachidonic acid, eicosanoic acid, erucic acid, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), nervonic acid, stearic acid, palmitic acid, arachidic acid, behenic acid, lignoceric acid, or a combination thereof. Slurry for all-solid-state batteries.

4. In Paragraph 3, The above fatty acid compound comprises at least one of oleic acid, stearic acid, palmitic acid, linolenic acid, or a combination thereof, Slurry for all-solid-state batteries.

5. In Paragraph 1, The molar ratio of the amine group in the above amine-based polymer to the above fatty acid compound is 1:0.005 to 1:0.5, Slurry for all-solid-state batteries.

6. In Paragraph 1, The weight ratio of the above sulfide-based solid electrolyte to the above additive is 100:0.1 to 100:10, Slurry for all-solid-state batteries.

7. In Paragraph 1, 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 (0≤x≤2), Li 7-a-c M1 a PS 6-c M2 c (0≤a≤2, 0≤c≤2) or at least one of a combination thereof, comprising The above M2 is F, Br, Cl, I, or a combination thereof, and the above M1 is 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, Slurry for all-solid-state batteries.

8. In Paragraph 1, The above-mentioned non-aqueous solvent comprises at least one of xylene, benzene, toluene, pentane, hexane, octyl acetate, nonyl acetate, isobutyl 2-methylpropanoate (IBIB), diisopropylbenzene (DIPB), or a combination thereof. Slurry for all-solid-state batteries.

9. In Paragraph 1, The above-mentioned slurry for a solid-state battery further comprises a binder, wherein The binder comprises at least one of polyvinylidenefluoride (PVdF), vinylidene fluoride / hexafluoropropylene copolymer (PVdF-HFP), styrene-butadiene rubber (SBR), nitrile butadiene rubber (NBR), polyacrylonitrile (PAN), polymethyl methacrylate (PMMA), polymethyl acrylate (PMA), polyethyl acrylate (PEA), polybutyl acrylate, polyacrylic acid (PAA), or a combination thereof. Slurry for all-solid-state batteries.

10. A positive current collector, and a positive active material layer on the positive current collector, wherein The above positive active material layer comprises a positive active material, a sulfide-based solid electrolyte, and an additive, and The above additive comprises amine-based polymers and fatty acid compounds, Cathode for all-solid-state batteries.

11. In Paragraph 10, The above amine-based polymer comprises at least one of polyethyleneimine (PEI), polyvinylamine (PVAm), polyallylamine (PAAm), polypropyleneimine (PPI), polyamideamine (PAMAM), polyamidoimine (PAI), or a combination thereof. Cathode for all-solid-state batteries.

12. In Paragraph 10, The above fatty acid compound comprises at least one of oleic acid, stearic acid, palmitic acid, linolenic acid, or a combination thereof, Cathode for all-solid-state batteries.

13. In Paragraph 10, The molar ratio of the amine group in the above amine-based polymer to the above fatty acid compound is 1:0.005 to 1:05, Cathode for all-solid-state batteries.

14. In Paragraph 10, The above positive active material layer further comprises a binder and a conductive material, Cathode for all-solid-state batteries.

15. A positive electrode comprising a positive current collector and a positive active material layer; A cathode comprising a cathode current collector; and A solid electrolyte layer between the anode and the cathode; comprising, At least one of the above positive active material layer or the above solid electrolyte layer comprises a sulfide-based solid electrolyte and an additive, and The above additive comprises amine-based polymers and fatty acid compounds, All-solid-state battery.

16. In Paragraph 15, The above solid electrolyte layer comprises the above sulfide-based solid electrolyte and the above additive, The above amine-based polymer comprises at least one of polyethyleneimine (PEI), polyvinylamine (PVAm), polyallylamine (PAAm), polypropyleneimine (PPI), polyamideamine (PAMAM), polyamidoimine (PAI), or a combination thereof. The above fatty acid compound comprises at least one of oleic acid, stearic acid, palmitic acid, linolenic acid, or a combination thereof, All-solid-state battery.

17. In Paragraph 16, The molar ratio of the amine group in the above amine-based polymer to the above fatty acid compound is 1:0.005 to 1:0.5, All-solid-state battery.

18. In Paragraph 16, The weight ratio of the sulfide-based solid electrolyte to the additive is 100:0.1 to 100:10, All-solid-state battery.

19. In Paragraph 16, The above solid electrolyte layer further comprises a binder, All-solid-state battery.

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