All-solid-state battery and method for manufacturing same

Abstract

The present invention relates to an all-solid-state battery and a manufacturing method therefor. More specifically, the all-solid-state battery comprises: a positive electrode layer including a positive electrode current collector and a positive electrode active material layer on the positive electrode current collector; a negative electrode layer including a negative electrode current collector and a coating layer on the negative electrode current collector; and a solid electrolyte layer between the positive electrode layer and the negative electrode layer, wherein the positive electrode layer further includes an inorganic insulating layer and a first organic insulating layer on one side surface of the positive electrode active material layer, and the negative electrode layer further includes a second organic insulating layer on one side surface of the coating layer.

Description

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

[0001] The present invention relates to an all-solid-state battery and a method for manufacturing 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 an all-solid-state battery that has excellent capacity and can prevent electrical short circuits.

[0005] Another problem that the present invention aims to solve is to provide a method for manufacturing an all-solid-state battery having the above characteristics.

[0006] A solid-state battery according to one embodiment of the present invention comprises: a positive electrode layer comprising a positive current collector and a positive active material layer on the positive current collector; a negative electrode layer comprising a negative current collector and a coating layer on the negative current collector; and a solid electrolyte layer between the positive electrode layer and the negative electrode layer, wherein the positive electrode layer further comprises an inorganic insulating layer and a first organic insulating layer on one side of the positive active material layer, and the negative electrode layer further comprises a second organic insulating layer on one side of the coating layer.

[0007] A method for manufacturing an all-solid-state battery according to one embodiment of the present invention comprises: forming an anode composite layer comprising an anode layer and a first solid electrolyte layer; forming a cathode composite layer comprising a cathode layer and a second solid electrolyte layer; and stacking the anode composite layer on the cathode composite layer to form an all-solid-state battery, wherein forming the anode composite layer comprises forming an inorganic insulating layer and a first organic insulating layer on one side of the anode active material layer of the anode layer, and forming the cathode composite layer may comprise forming a second organic insulating layer on one side of the coating layer of the cathode layer.

[0008] An all-solid-state battery according to one embodiment of the present invention has excellent capacity and excellent energy density, and can have a long lifespan by preventing electrical short circuits.

[0009] A method for manufacturing an all-solid-state battery according to one embodiment of the present invention can manufacture an all-solid-state battery having the above characteristics and can reduce the production cost of the all-solid-state battery.

[0010] FIG. 1 is a plan view of an all-solid-state battery according to embodiments of the present invention.

[0011] Figure 2 is a cross-sectional view along the line A-A' of Figure 1.

[0012] Figure 3 is a cross-sectional view along the line B-B' of Figure 1.

[0013] Figures 4 to 8 are enlarged views of the M region of Figure 3.

[0014] FIGS. 9 to 11 are enlarged views of the N region of FIG. 3.

[0015] FIGS. 12 to 14 are cross-sectional views for explaining a method for manufacturing an all-solid-state battery according to embodiments of the present invention.

[0016] FIGS. 15 to 17 are drawings for explaining an anode layer according to embodiments of the present invention.

[0017] FIG. 18 is a cross-sectional view illustrating an all-solid-state battery according to another embodiment of the present invention.

[0018] FIG. 19 is a cross-sectional view illustrating an all-solid-state battery according to another embodiment of the present invention.

[0019] 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.

[0020] 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.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026]

[0027] FIG. 1 is a plan view of an all-solid-state battery according to embodiments of the present invention. FIG. 2 is a cross-sectional view along line A-A' of FIG. 1. FIG. 3 is a cross-sectional view along line B-B' of FIG. 1. FIG. 4 to 8 are enlarged views of region M of FIG. 3. FIG. 9 to 11 are enlarged views of region N of FIG. 3.

[0028] Referring to FIGS. 1, 2, and 3, a unit cell (CEL) of an all-solid-state battery according to the present invention 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, not limited thereto, the unit cell (CEL) 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).

[0029] An anode layer (100) according to one embodiment of the present invention may include 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.

[0030] 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.

[0031] To increase the bonding strength between the positive current collector (110) and the positive active material layer (120), a carbon-containing layer with a thickness of 0.1 μm to 4 μm, or 0.1 μm to 1 μm, may be further disposed between the positive current collector (110) and the positive active material layer (120). As an example, the carbon-containing layer may include a carbon-based material and a binder. For example, the carbon-based material may include at least one selected from the group consisting of graphite, carbon black, acetylene black, carbon nanofibers, and carbon nanotubes. For example, the binder may include at least one selected from the group consisting of polyvinylidene fluoride, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, vinylidene fluoride / hexafluoropropylene copolymer, polyacrylonitrile, and polymethyl methacrylate. For example, the binder content may be 30% to 50% by weight relative to the total weight of the carbon-containing layer.

[0032] The positive active material of the positive active material layer (120) may include a material capable of reversibly absorbing and desorbing lithium ions. The positive active material may include a plurality of particles. The positive 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, nickel sulfide, copper sulfide, lithium sulfide, iron oxide, or vanadium oxide, but is not necessarily limited to these. Each positive active material may be a single material or a mixture of two or more materials.

[0033] 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 Ni 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 Ni 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 Ni 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 bO2(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-f It 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.

[0034] The positive electrode 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 z O2(NCM) (0 <x<1,0<y<1, 0<z<1, x+y+z=1) 등의 삼원계 리튬전이금속산화물일 수 있다. 양극 활물질(PAM)이 층상암염형 구조를 갖는 삼원계 리튬전이금속산화물을 포함하는 경우, 단위 셀(CEL)의 에너지 밀도가 커지고 열안정성이 향상될 수 있다.

[0035] The aforementioned compound contained in the positive electrode active material may be covered by a coating layer (not shown). The positive electrode 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 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.

[0036] When the cathode active material is a ternary lithium transition metal oxide, such as NCA or NCM, containing nickel (Ni), it is possible to increase the capacity density of the unit cell (CEL) and reduce the metal leaching of the cathode active material in the charged state. Consequently, the cycle characteristics of the unit cell (CEL) in the charged state are improved. Meanwhile, "cycle characteristics" refers to the degree of degradation of the unit cell (CEL) due to charging and discharging; a unit cell (CEL) with high cycle characteristics experiences less degradation due to charging and discharging, while a unit cell (CEL) with low cycle characteristics may experience greater degradation due to charging and discharging.

[0037] The positive active material may have particle shapes such as, for example, spheres or ellipsoids. The particle size and content of the positive active material are not particularly limited.

[0038] The solid electrolyte of the positive active material layer (120) may have a particle shape. The solid electrolyte may be dispersed among the positive active materials. The solid electrolyte may include a sulfide-based solid electrolyte with excellent lithium ion conductivity characteristics. Sulfide-based solid electrolytes 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), or Li 7-x PS 6-x I x It may include at least one of (0≤x≤2).

[0039] 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), or Li 7-x PS 6-x I xIt may be an argyrodite-type compound comprising at least one of (0≤x≤2). In particular, the sulfide-based solid electrolyte may be an argyrodite-type compound comprising at least one of Li6PS5Cl, Li6PS5Br, or Li6PS5I.

[0040] 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, I, 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.

[0041]

[0042] 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.

[0043] The solid electrolyte in the positive active material layer (120) may have a smaller average particle size compared to the solid electrolyte in the solid electrolyte layer (300) described later. For example, the average particle size of the solid electrolyte in the positive 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 of the solid electrolyte in the solid electrolyte layer (300). Meanwhile, the average particle size may be the median diameter measured using a laser particle size distribution meter.

[0044] The positive active material layer (120) may 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 and the solid electrolyte. The conductive material may include a carbon-based material. The conductive material may include, for example, at least one of graphite, carbon black, acetylene black, carbon nanofiber, or carbon nanotube.

[0045] The positive active material layer (120) may further include a binder. The binder may bind the positive active material, solid electrolyte, and conductive material within the positive active material layer (120) together. The binder may include a material to improve the bonding strength between the positive active material layer (120) and the positive current collector (110). The binder may include, for example, at least one of polyvinylidene fluoride, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, vinylidene fluoride / hexafluoropropylene copolymer, polyacrylonitrile, or polymethyl methacrylate.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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), aluminum (Al), silver (Ag), 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, more specifically 7 μm to 10 μm.

[0050] 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.

[0051] The coating layer (220) can allow lithium metal to grow between the unit cell (CEL) 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.

[0052] 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 (or composite) of carbon black and silver (Ag).

[0053] Carbon may originate from carbon assemblies added during the manufacture of the coating layer (220). The carbon assemblies may be secondary particles formed by the aggregation of primary particles. For example, the average particle size of the primary particles may be 20 nm to 100 nm, and the average particle size of the secondary particles may be 1 µm to 20 µm. The carbon in the coating layer (220) may mainly consist of primary particles.

[0054] 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.

[0055] 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 cause the coating layer (220) to collapse, thereby degrading the cycle characteristics of the unit cell (CEL). If the thickness of the coating layer (220) increases excessively, the energy density of the unit cell (CEL) decreases and the internal resistance of the unit cell (CEL) due to the coating layer (220) increases, which may degrade the cycle characteristics of the cell.

[0056] 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).

[0057] A solid electrolyte layer (300) may be provided between the positive electrode layer (100) and the negative electrode layer (200). The solid electrolyte layer (300) may include a sulfide-based solid electrolyte with excellent lithium ion conductivity characteristics. The solid electrolyte in the solid electrolyte layer (300) may be the same as or different from any one of the materials included in the solid electrolyte in the aforementioned positive electrode active material layer (120).

[0058] The solid electrolyte in the solid electrolyte layer (300) may have particle shapes such as spheres or ellipsoids.

[0059] The solid electrolyte within the solid electrolyte layer (300) may include a sulfide-based solid electrolyte. The solid electrolyte may be amorphous, crystalline, or a mixture thereof. Additionally, 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.

[0060] In one embodiment, the 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), or Li 7-x PS 6-x I x It may include an argyrodite-type compound comprising at least one of (0≤x≤2). The solid electrolyte may include an argyrodite-type compound comprising at least one of Li6PS5Cl, Li6PS5Br, or Li6PS5I.

[0061] In another embodiment, the solid electrolyte is Li 7-a M a PS 6-c X c It may include an argyrodite-type compound comprising. Here, X may be Cl, Br, or a combination thereof. M may be Na, K, Fe, Mg, Ca, Ag, Cu, Zr, Zn, or a combination thereof. a and c may each be real numbers between 0 and 2.

[0062] 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.

[0063] The solid electrolyte layer (300) may further include a binder. The binder included in the solid electrolyte layer (300) is not limited to, for example, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, etc. For example, the binder included in the solid electrolyte layer (300) may include at least one selected from the group consisting of styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, and polyacrylate. The binder of the solid electrolyte layer (300) may be the same as or different from the binder included in the positive active material layer (120) or the binder included in the coating layer (220).

[0064] 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).

[0065] The second solid electrolyte layer (320) can be in direct contact with the coating layer (220). By doing so, the second solid electrolyte layer (320) can suppress lithium dendrites formed between the coating layer (220) and the negative electrode current collector (210). The second solid electrolyte layer (320) can effectively suppress negative electrode side reactions. By doing so, the cell performance of the all-solid-state battery according to the present invention can be improved.

[0066] 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). In another example, the second thickness (TK2) may be equal to or greater than the first thickness (TK1).

[0067] 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). An anode composite layer (CSH) can be laminated on the cathode composite layer (ASH).

[0068] 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).

[0069] 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).

[0070] 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).

[0071] For example, the difference between the second width (WI2) and the first width (WI1) may be 10 mm or less. Specifically, the difference between the second width (WI2) and the first width (WI1) may be 8 mm or less, 5 mm or less, 3 mm or less, and 2 mm or less. The difference between the second width (WI2) and the first width (WI1) may be greater than 0 mm, greater than 0.1 mm, greater than 0.5 mm, and greater than 1 mm.

[0072] For example, the difference between the third width (WI3) and the fourth width (WI4) may be 10 mm or less. Specifically, the difference between the third width (WI3) and the fourth width (WI4) may be 8 mm or less, 5 mm or less, 3 mm or less, and 2 mm or less. The difference between the fourth width (WI4) and the third width (WI3) may be greater than 0 mm, greater than 0.1 mm, greater than 0.5 mm, and greater than 1 mm.

[0073] If the above numerical range is exceeded, the size of the anode layer (100) becomes relatively smaller, so the discharge capacity is lowered and the energy density of the all-solid-state battery may decrease. If the above numerical range is not met, it is difficult to suppress the formation of lithium dendrites in the cathode, so there may be a risk of a short circuit.

[0074] Referring to FIGS. 3 and 4, the anode layer (100) may further include an inorganic insulating layer (ISL1) and a first organic insulating layer (ISL2). The inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2) may be located on the anode current collector (110). The inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2) may be located on an uninsulated portion. The inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2) may be located in an area of ​​the anode current collector (110) that is not covered by the anode active material layer (120).

[0075] 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). The positive tab (CTB) may be an uncovered area. The positive tab (CTB) may be an area not covered by the positive active material layer (120). For example, a portion of the positive tab (CTB) may be covered by an inorganic insulating layer (ISL1) or a first organic insulating layer (ISL2). A portion of the positive tab (CTB) may be exposed by the inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2). A portion of the exposed positive tab (CTB) may be electrically connected to a positive lead.

[0076] The positive active material layer (120) may include a central region (CTR1) and an edge region (EDG1). The edge region (EDG1) may be a region protruding toward the positive tab (CTB). The edge region (EDG1) may be a region protruding toward the first solid electrolyte layer (310) in the second direction (D2). The positive active material layer (120) may be formed by applying a positive active material layer slurry onto a positive current collector (110), drying it, performing a pressurizing process, and then performing slitting and notching processes. When the positive active material layer slurry is applied, dried, and pressurized, the positive active material layer (120) may have an edge region (EDG1) protruding toward the positive tab (CTB).

[0077] The edge region (EDG1) may be an area with relatively low density where sufficient pressure is not applied. The thickness of the edge region (EDG1) may gradually decrease as it moves toward the second direction (D2). For example, the length (d) of the edge region (EDG1) along the second direction (D2) EDG1 ) may be about 1 mm. The edge region (EDG1) may have a curved surface toward the positive tab (CTB). The curved surface may be one side (SD1) of the positive active material layer (120). One side (SD1) of the positive active material layer (120) may be adjacent to the positive tab (CTB).

[0078] When a slitting and notching process is performed on the anode layer (100), an anode tab (CTB) may be formed. A portion of the edge region adjacent to the anode tab (CTB) (e.g., EDG1) may not be removed even when the slitting and notching process is performed. For example, the remaining edge region may be removed through the slitting and notching process, and a flat sidewall may be formed on the anode active material layer (120).

[0079] The central region (CTR1) of the positive active material layer (120) may be the remaining region excluding the edge region (EDG1). In one embodiment, the central region (CTR1) may have a constant thickness along the second direction (D2).

[0080] The inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2) may be located on one side (SD1) of the positive active material layer (120). The inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2) may be adjacent to the positive tab (CTB) rather than the positive active material layer (120). The first organic insulating layer (ISL2) may be adjacent to the positive tab (CTB) rather than the inorganic insulating layer (ISL1). The inorganic insulating layer (ISL1) may be located between the first organic insulating layer (ISL2) and the positive active material layer (120).

[0081] An inorganic insulating layer (ISL1) may be located on the positive current collector (110). An inorganic insulating layer (ISL1) may be located on the edge region (EDG1). The inorganic insulating layer (ISL1) may cover at least a portion of one side (SD1) of the positive active material layer (120). The inorganic insulating layer (ISL1) may be adhered to one side (SD1) of the positive active material layer (120) to bury the edge region (EDG1). The inorganic insulating layer (ISL1) may prevent detachment of the edge region (EDG1), which has a relatively low density, and prevent a short circuit of the all-solid-state battery.

[0082] The inorganic insulating layer (ISL1) may include at least one of an inorganic material or a binder. As an example, the inorganic insulating layer (ISL1) may include both an inorganic material and a binder. The inorganic insulating layer (ISL1) may have excellent electrical insulation properties, excellent mechanical strength, and excellent stability in extreme environments such as high temperature and high pressure.

[0083] For example, the inorganic material may include at least one selected from the group consisting of Al2O3, Al(OH)3, AlOOH, SiO2, MgO, TiO2, SnO2, and ZnO. For example, the inorganic material may be AlOOH.

[0084] For example, the binder may comprise at least one selected from the group consisting of poly(vinylidene fluoride-co-hexafluoropropylene) copolymer, polyacrylate, polyvinylidenefluoride, styrene butadiene rubber, polytetrafluoroethylene, polyacrylonitrile, or polymethyl methacrylate. For example, the binder may be a vinylidene fluoride-co-hexafluoropropylene copolymer having a hexafluoropropylene content of 30 weight%.

[0085] In the inorganic insulating layer (ISL1), the inorganic material and binder may be included in a weight ratio of 5:5 to 8:2, or a weight ratio of 7:3 to 8:2. If the weight ratio of the inorganic material and binder satisfies the range described above, the inorganic insulating layer (ISL1) can be adhered to one side (SD1) of the positive active material layer (120) to bury the edge region (EDG1). The inorganic insulating layer (ISL1) can prevent the detachment of the edge region (EDG1), which has a relatively low density, and can prevent a short circuit in the all-solid-state battery. In addition, the inorganic insulating layer (ISL1) has excellent electrical insulation properties, excellent mechanical strength, and excellent stability in extreme environments such as high temperatures. The inorganic insulating layer (ISL1) can provide an environment in which the first organic insulating layer (ISL2) can function stably in such an environment.

[0086] An inorganic insulating layer (ISL1) can be coated on one side (SD1) of the positive active material layer (120). One side (SD2) of the inorganic insulating layer (ISL1) may have a curved surface toward the positive tab (CTB).

[0087] The inorganic insulating layer (ISL1) may include a first end (ED1) and a second end (ED2). The first end (ED1) may be an end where one side (SD2) of the inorganic insulating layer (ISL1) meets the positive current collector (110). The second end (ED2) may be an end where the inorganic insulating layer (ISL1) meets the upper part of the positive active material layer (120).

[0088] For example, the horizontal distance (d12) from the first end (ED1) to the second end (ED2) may be 0.5 mm to 2.7 mm. For example, the horizontal distance (d12) from the first end (ED1) to the second end (ED2) may be 0.5 mm to 2.6 mm.

[0089] For example, the horizontal distance (d12) from the first end (ED1) to the second end (ED2) is the length (d) in the second direction (D2) of the edge region (EDG1). EDG1It may be 0.5 to 2.7 times that of ). For example, the horizontal distance (d12) from the first end (ED1) to the second end (ED2) is the length (d) in the second direction of the edge region (EDG1). EDG1 It can be 0.5 to 2.6 times compared to ).

[0090] If the horizontal distance (d12) from the first end (ED1) to the second end (ED2) satisfies the range described above, the inorganic insulating layer (ISL1) can be adhered to one side (SD1) of the positive active material layer (120) and sufficiently bury the edge region (EDG1) without causing a decrease in capacity due to encroachment between the positive active material layer (120) and the first solid electrolyte layer (310).

[0091] The first organic insulating layer (ISL2) may be located on the positive current collector (110). The first organic insulating layer (ISL2) may be located between the inorganic insulating layer (ISL1) and the positive tab (CTB).

[0092] For example, the first organic insulating layer (ISL2) may cover at least a portion of one side (SD2) of the inorganic insulating layer (ISL1). For example, the inorganic insulating layer (ISL1) may have a relatively rough surface, and the first organic insulating layer (ISL2) may be easily coated on the inorganic insulating layer (ISL1), and the durability of the coating may be enhanced.

[0093] As another example, the first organic insulating layer (ISL2) may not cover one side (SD2) of the inorganic insulating layer (ISL2) but may be located in contact with the inorganic insulating layer (ISL2).

[0094] The first organic insulating layer (ISL2) can prevent an electrical short circuit resulting from contact with the anode tab (CTB) and the cathode layer (200), etc. The first organic insulating layer (ISL2) is relatively flexible, so it can be uniformly formed on the inorganic insulating layer (ISL1) and the anode tab (CTB) and can flexibly respond to mechanical deformation. The first organic insulating layer (ISL2) can protect the inorganic insulating layer (ISL1) from external shock or mechanical stress.

[0095] For example, the first organic insulating layer (ISL2) may comprise at least one selected from the group consisting of polyamideimide, polyimide, polyethersulfone, polyurethane, polycarbonate, epoxy resin, polysulfide, and polybenzimidazole. For example, the first organic insulating layer (ISL2) may be polyamideimide.

[0096] The thickness of the first organic insulating layer (ISL2) in the third direction (D3) may be 2 μm to 10 μm.

[0097] The first organic insulating layer (ISL2) may be coated on one side (SD1) of the positive active material layer (120). One side (SD3) of the first organic insulating layer (ISL2) may have a curved surface toward the positive tab (CTB).

[0098] The first organic insulating layer (ISL2) may include a third end (ED3) and a fourth end (ED4). The third end (ED3) may be an end where one side (SD3) of the first organic insulating layer (ISL2) meets the positive current collector (110). The fourth end (ED4) may be an end where the first organic insulating layer (ISL2) meets the top of the inorganic insulating layer (ISL1).

[0099] For example, the horizontal distance (d13) from the first end (ED1) to the third end (ED3) may be 2 mm to 9 mm. For example, the horizontal distance (d13) from the first end (ED1) to the third end (ED3) may be 2.1 mm to 8.8 mm.

[0100] For example, the horizontal distance (d13) from the first end (ED1) to the third end (ED3) is the length (d) in the second direction (D2) of the edge region (EDG1). EDG1 It can be 2 to 9 times that of ). For example, the horizontal distance (d13) from the first end (ED1) to the third end (ED3) is the length (d) in the second direction (D2) of the edge region (EDG1). EDG1 It can be 2.2 to 8.8 times compared to ).

[0101] If the horizontal distance (d13) from the first end (ED1) to the third end (ED3) satisfies the range described above, it is possible to prevent welding defects of the anode tab (CTB) and prevent electrical short circuits caused by contact between the anode tab (CTB) and the cathode layer (200), etc.

[0102] For example, the horizontal distance (d14) from the first end (ED1) to the fourth end (ED4) may be 0 mm to 2.7 mm, 0 mm to 0.5 mm, or greater than 0 mm and less than or equal to 0.5 mm.

[0103] For example, the horizontal distance (d14) from the first end (ED1) to the fourth end (ED4) is the length (d) in the second direction (D2) of the edge region (EDG1). EDG1 It may be 0 to 2.7 times, 0 to 0.5 times, or greater than 0 times and less than or equal to 0.5 times compared to ).

[0104] If the horizontal distance (d14) from the first end (ED1) to the fourth end (ED4) satisfies the range described above, the first organic insulating layer (ISL2) may not cause a decrease in capacity due to intrusion between the positive active material layer (120) and the first solid electrolyte layer (310).

[0105] FIGS. 4 to 8 are cross-sectional views illustrating various embodiments of the M region.

[0106] For example, referring to FIG. 4, the inorganic insulating layer (ISL1) may completely cover one side (SD1) of the positive active material layer (120), and the first organic insulating layer (ISL2) may cover a portion of one side (SD2) of the inorganic insulating layer (ISL1). A portion of one side (SD2) of the inorganic insulating layer (ISL1) may be exposed by the first organic insulating layer (ISL2).

[0107] For example, referring to FIG. 5, the inorganic insulating layer (ISL1) can completely cover one side (SD1) of the positive active material layer (120), and the first organic insulating layer (ISL2) can completely cover one side (SD2) of the inorganic insulating layer (ISL1).

[0108] For example, referring to FIG. 6, the inorganic insulating layer (ISL1) may completely cover one side (SD1) of the positive active material layer (120), and the first organic insulating layer (ISL2) may cover a portion of one side (SD2) of the inorganic insulating layer (ISL1). A portion of one side (SD2) of the inorganic insulating layer (ISL1) may be exposed by the first organic insulating layer (ISL2). The inorganic insulating layer (ISL1) may have a relatively small horizontal distance (d12).

[0109] For example, referring to FIG. 7, an inorganic insulating layer (ISL1) may cover a portion of one side (SD1) of the positive active material layer (120), and a first organic insulating layer (ISL2) may cover a portion of one side (SD2) of the inorganic insulating layer (ISL1). A portion of one side (SD1) of the positive active material layer (120) may be exposed by the inorganic insulating layer (ISL1), and a portion of one side (SD2) of the inorganic insulating layer (ISL1) may be exposed by the first organic insulating layer (ISL2).

[0110] For example, referring to FIG. 8, the inorganic insulating layer (ISL1) may cover a portion of one side (SD1) of the positive active material layer (120), and the first organic insulating layer (ISL2) may cover the entire portion of one side (SD2) of the inorganic insulating layer (ISL1). A portion of one side (SD1) of the positive active material layer (120) may be exposed by the inorganic insulating layer (ISL1).

[0111] Referring to FIGS. 3 and FIGS. 9, the cathode layer (200) may further include a second organic insulating layer (ISL3). The second organic insulating layer (ISL3) may be located on the cathode current collector (210). The second organic insulating layer (ISL3) may be located on an uncoated portion. The second organic insulating layer (ISL3) may be located in an area of ​​the cathode current collector (210) that is not covered by a coating layer (220).

[0112] The cathode current collector (210) may include a cathode tab (ATB). The cathode tab (ATB) may be a protruding area of ​​the cathode current collector (210). The cathode tab (ATB) may be an uncoated area. The cathode tab (ATB) may be an area not covered by the coating layer (220). For example, a portion of the cathode tab (ATB) may be covered by a second organic insulating layer (ISL3). A portion of the cathode tab (ATB) may be exposed by the second organic insulating layer (ISL3). The exposed portion of the cathode tab (ATB) may be electrically connected to a cathode lead.

[0113] The coating layer (220) may include a central region (CTR2) and an edge region (EDG2). The edge region (EDG2) may be a region protruding toward the cathode tab (ATB). The edge region (EDG2) may be a region protruding from the second solid electrolyte layer (320) in the opposite direction of the second direction (D2). The coating layer (220) may be formed by applying a coating layer slurry onto the cathode current collector (210), drying it, performing a pressurizing process, and then performing slitting and notching processes. When the coating layer slurry is applied, dried, and pressurized, the coating layer (220) may have an edge region (EDG2) protruding toward the cathode tab (ATB).

[0114] The edge region (EDG2) may be an area with relatively low density where sufficient pressure is not applied. The thickness of the edge region (EDG2) may gradually decrease as it moves in the opposite direction of the second direction (D2). For example, the length (d) of the edge region (EDG2) along the second direction (D2). EDG2 ) may be smaller than 1 mm. The edge region (EDG2) may have a curved surface toward the cathode tab (ATB). The curved surface may be one side (SD3) of the coating layer (220). One side (SD3) of the coating layer (220) may be adjacent to the cathode tab (ATB).

[0115] When a slitting and notching process is performed on the cathode layer (200), a cathode tab (ATB) may be formed. A portion of the edge region adjacent to the cathode tab (ATB) (e.g., EDG2) may not be removed even when the slitting and notching process is performed. For example, the remaining edge region may be removed through the slitting and notching process, and a flat sidewall may be formed on the coating layer (220).

[0116] The central region (CTR2) of the coating layer (220) may be the remaining region excluding the edge region (EDG2). In one embodiment, the central region (CTR2) may have a constant thickness along the second direction (D2).

[0117] The second organic insulating layer (ISL3) may be located on the negative current collector (210). The second organic insulating layer (ISL3) may be adjacent to the negative tab (ATB) than the coating layer (220). The second organic insulating layer (ISL3) may be located on the edge region (EDG2) of the coating layer (220). The second organic insulating layer (ISL3) may cover at least a portion of one side (SD4) of the coating layer (220). The second organic insulating layer (ISL3) may be adhered to one side (SD4) of the coating layer (220) to bury the edge region (EDG2). The second organic insulating layer (ISL3) can prevent detachment of the edge region (EDG2), which has a relatively low density, and can prevent a short circuit of the all-solid-state battery. The second organic insulating layer (ISL3) can prevent an electrical short circuit resulting from contact between the negative tab (ATB) and the positive layer (100), etc. The second organic insulating layer (ISL3) is relatively flexible, so it can be uniformly formed on the coating layer (220) and the cathode tab (ATB) and can flexibly respond to mechanical deformation.

[0118] For example, the second organic insulating layer (ISL3) may comprise at least one selected from the group consisting of polyamideimide, polyimide, polyethersulfone, polyurethane, polycarbonate, epoxy resin, polysulfide, and polybenzimidazole. For example, the second organic insulating layer (ISL3) may be polyamideimide.

[0119] The thickness of the second organic insulating layer (ISL3) in the third direction (D3) may be 2 μm to 10 μm.

[0120] The second organic insulating layer (ISL3) may be coated on one side (SD4) of the coating layer (220). One side (SD5) of the second organic insulating layer (ISL3) may have a curved surface toward the negative tab (ATB).

[0121] The second organic insulating layer (ISL3) may include a fifth end (ED5), a sixth end (ED6), and a seventh end (ED7). The fifth end (ED5) may be an end where one side (SD4) of the coating layer (220) meets the negative current collector (210). The sixth end (ED6) may be an end where one side (SD5) of the second organic insulating layer (ISL3) meets the negative current collector (210). The seventh end (ED7) may be an end where the second organic insulating layer (ISL3) meets the upper part of the coating layer (220).

[0122] For example, the horizontal distance (d56) from the 5th end (ED5) to the 6th end (ED6) may be 0.3 mm to 4.4 mm.

[0123] If the horizontal distance (d56) from the 5th end (ED5) to the 6th end (ED6) satisfies the range described above, the edge region (EDG2) can be sufficiently filled by being adhered to one side (SD4) of the coating layer (220). In addition, while preventing welding defects of the cathode tab (ATB), electrical short circuits caused by contact between the cathode tab (ATB) and the anode layer (100), etc., can be prevented.

[0124] For example, the horizontal distance (d57) from the fifth end (ED5) to the seventh end (ED7) may be 2.7 mm or less. For example, the horizontal distance (d57) from the fifth end (ED5) to the seventh end (ED7) may be 0.001 mm to 2.7 mm, 0.005 mm to 2.7 mm, 0.01 mm to 2.7 mm, 0.1 mm to 2.7 mm, 1 mm to 2.7 mm, or 1.5 mm to 2.6 mm.

[0125] If the horizontal distance (d57) from the 5th end (ED5) to the 7th end (ED7) satisfies the range described above, the second organic insulating layer (ISL3) may not cause a decrease in capacity due to excessively covering the upper part of the coating layer (220).

[0126] FIGS. 9 to 11 are cross-sectional views illustrating various embodiments of the N region.

[0127] For example, referring to FIG. 9, the second organic insulating layer (ISL3) may cover the entire side (SD4) of the coating layer (220) and cover a portion of the upper surface of the central region (CTR2) of the coating layer (220).

[0128] For example, referring to FIG. 10, the second organic insulating layer (ISL3) can cover the entire side (SD4) of the coating layer (220).

[0129] For example, referring to FIG. 11, the second organic insulating layer (ISL3) may cover a portion of one side (SD4) of the coating layer (220). A portion of one side (SD4) of the coating layer (220) may be exposed by the second organic insulating layer (ISL3).

[0130] For example, referring again to FIG. 3, the positive tab (CTB) and the negative tab (ATB) can be drawn out in opposite directions, and the inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2) can be located in opposite directions to the second organic insulating layer (ISL3). By drawing out the positive tab (CTB) and the negative tab (ATB) in opposite directions, the flow of current inside the battery can be optimized, problems such as overload and heat generation can be prevented, and safety can be increased. Since the inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2) are located in opposite directions to the second organic insulating layer (ISL3), electrical short circuits caused by contact between the positive tab (CTB) and the negative layer (200), etc., and electrical short circuits caused by contact between the negative tab (ATB) and the positive layer (100), etc., can be prevented, and safety can be further increased.

[0131] As another example, unlike the illustration, the positive tab (CTB) and the negative tab (ATB) can be drawn out side by side on one side, and the inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2) can be positioned in the same direction as the second organic insulating layer (ISL3). By drawing out the positive tab (CTB) and the negative tab (ATB) side by side on one side, space can be saved and wiring efficiency can be increased. Since the inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2) are positioned in the same direction as the second organic insulating layer (ISL3), it is possible to prevent electrical short circuits caused by contact between the positive tab (CTB) or the negative tab (ATB) and the negative layer (100), as well as electrical short circuits caused by contact between the positive tab (CTB) and the negative tab (ATB), thereby providing safety.

[0132]

[0133] FIGS. 12 to 14 are schematic diagrams for explaining a method for manufacturing an all-solid-state battery according to embodiments of the present invention.

[0134] A method for manufacturing an all-solid-state battery according to the present invention may include forming an anode composite layer (CSH); forming a cathode composite layer (ASH); and forming an all-solid-state battery by stacking the anode composite layer (CSH) on the cathode composite layer (ASH).

[0135] Referring to FIG. 12, forming the positive composite layer (CSH) may include forming a positive active material layer (120) on a positive current collector (110); forming an inorganic insulating layer (ISL1) and a first organic insulating layer (ISL2) on one side of the positive active material layer (120); and forming a first solid electrolyte layer (310) on the positive active material layer (120).

[0136] The positive active material layer (120) can be formed by applying, drying, and rolling a positive active material layer slurry on the positive current collector (110).

[0137] The positive electrode active material layer slurry may include a positive electrode active material, a solid electrolyte, a conductive material, a binder, and a solvent. The descriptions of the positive electrode active material, solid electrolyte, conductive material, and binder are as described above. The solvent may be any solvent capable of sufficiently dispersing the positive electrode active material, solid electrolyte, conductive material, and binder, and is not particularly limited. For example, the solvent may include xylene, etc.

[0138] Coating can be any method capable of applying a slurry onto a substrate in the relevant field. For example, coating can be performed using a bar coater, a blade coater, etc. The solvent can be evaporated through drying.

[0139] Rolling can be performed using a roll press. Through rolling, the positive active material layer (120) can have a desired thickness.

[0140] When the positive active material layer slurry is applied, dried, and rolled, the positive active material layer (120) formed may have an edge region protruding from the side.

[0141] To have a desired horizontal distance (see d12 in FIG. 4), an inorganic insulating layer (ISL1) may be formed on one side of the edge region of the positive active material layer (120) (see EDG1, SD1 in FIG. 4). For example, the inorganic insulating layer (ISL1) may be formed by applying and drying an inorganic insulating layer composition on one side of the positive active material layer (120) (see SD1 in FIG. 4). The inorganic insulating layer composition may include the inorganic material and binder described above and a solvent. The solvent only needs to be capable of dispersing and dissolving the inorganic material and the binder. For example, the solvent may include water, alcohol, acidic solution, dimethyl sulfoxide, N-methyl-2-pyrrolidone, dimethylformamide, acetone, N,N-dimethylacetamide, tetrahydrofuran, etc. Thus, one side of the inorganic insulating layer (ISL1) (see SD2 in FIG. 4) may have a curved surface toward the anode tab (CTB).

[0142] To have a desired horizontal distance (see d13 and d14 in FIG. 4), the first organic insulating layer (ISL2) may be formed on one side of the edge region of the positive active material layer (120) (see EDG1 and SD1 in FIG. 4). For example, the first organic insulating layer (ISL2) may be formed by applying and drying a first organic insulating layer composition on one side of the inorganic insulating layer (ISL1) (see SD2 in FIG. 4). The first organic insulating layer composition may include the polymer and solvent described above. The solvent may be capable of dispersing and dissolving the polymer described above. For example, the solvent may include N-methyl-2-pyrrolidone, dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran, etc. Thus, one side of the first organic insulating layer (ISL2) (see SD3 in FIG. 4) may have a curved surface toward the anode tab (CTB).

[0143] Before forming the first solid electrolyte layer (310), a slitting and notching process may be performed on the positive active material layer (120). For example, the slitting and notching process may be performed after forming an inorganic insulating layer (ISL1) and a first organic insulating layer (ISL2) in the edge region of the positive active material layer (120). For another example, the slitting and notching process may be performed before forming the inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2) in the edge region of the positive active material layer (120).

[0144] A positive electrode tab (CTB) can be formed through a slitting and notching process. A portion of the edge region of the positive electrode active material layer (120) adjacent to the positive electrode tab (CTB) (e.g., see EDG1 in FIG. 4) may not be removed even after the slitting and notching process is performed. For example, the remaining edge region may be removed through the slitting and notching process, and a flat sidewall may be formed on the positive electrode active material layer (120).

[0145] Forming a first solid electrolyte layer (310) on the positive active material layer (120) may involve directly applying a first solid electrolyte layer slurry onto the positive active material layer (120) or transferring the first solid electrolyte layer (310). By doing so, a positive composite layer (CSH) can be formed.

[0146] Referring to FIG. 13, forming a cathode composite layer (ASH) may include forming a coating layer (220) on a cathode current collector (210); forming a second organic insulating layer (ISL3) on one side of the coating layer (220); and forming a second solid electrolyte layer (320) on the coating layer (220).

[0147] The coating layer (220) can be formed by applying, drying, and rolling a coating layer slurry on the negative current collector (210), and performing slitting and notching processes.

[0148] The coating layer slurry may include a metal, carbon, and a solvent. The description of the metal and carbon is the same as described above. The solvent may be any solvent capable of sufficiently dispersing the metal and carbon, and is not particularly limited. For example, the solvent may include N-methylpyrrolidone, distilled water, etc.

[0149] Coating can be any method capable of applying a slurry onto a substrate in the relevant field. For example, coating can be performed using a bar coater, a blade coater, etc. The solvent can be evaporated through drying.

[0150] Rolling can be performed using a roll press. Through rolling, the coating layer (220) can have a desired thickness.

[0151] When the coating layer slurry is applied, dried, and rolled, the coating layer (220) formed may have an edge area protruding from the side.

[0152] To have a desired horizontal distance (see d56 and d57 in FIG. 9), a second organic insulating layer (ISL3) may be formed on one side of the edge region of the coating layer (220) (see SD4 in FIG. 9). For example, the second organic insulating layer (ISL3) may be formed by applying and drying a second organic insulating layer composition on one side of the coating layer (220) (see SD4 in FIG. 9). The second organic insulating layer composition may include the polymer and solvent described above. The solvent may be capable of dispersing and dissolving the polymer described above. For example, the solvent may include N-methyl-2-pyrrolidone, dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran, etc. Thus, one side of the second organic insulating layer (ISL3) (see SD5 in FIG. 9) may have a curved surface toward the cathode tab (ATB).

[0153] Before forming the second solid electrolyte layer (320), a slitting and notching process may be performed on the coating layer (220). For example, the slitting and notching process may be performed after forming the second organic insulating layer (ISL3) on the edge region of the coating layer (220). For another example, the slitting and notching process may be performed before forming the second organic insulating layer (ISL3) on the edge region of the coating layer (220).

[0154] A cathode tab (ATB) can be formed through a slitting and notching process. A portion of the edge region of the coating layer (220) adjacent to the cathode tab (ATB) (e.g., see EDG2 in FIG. 9) may not be removed even after the slitting and notching process is performed. For example, the remaining edge region may be removed through the slitting and notching process, and a flat sidewall may be formed on the coating layer (220).

[0155] Forming a second solid electrolyte layer (320) on a coating layer (220) may involve directly applying a second solid electrolyte layer slurry onto the coating layer (220) or transferring the second solid electrolyte layer (320). By doing so, a negative electrode composite layer (ASH) can be formed.

[0156] Referring to FIG. 14, a unit cell (CEL) of an all-solid-state battery can be formed by laminating an anode composite layer (CSH) on a cathode composite layer (ASH) so that the first solid electrolyte layer (310) and the second solid electrolyte layer (320) come into contact with each other. A pressurizing process can be performed on the cathode composite layer (ASH) and the anode composite layer (CSH) to laminate the anode composite layer (CSH) on the cathode composite layer (ASH).

[0157]

[0158] FIGS. 15 to 17 are drawings for explaining an anode layer (100) according to embodiments of the present invention. FIGS. 15 to 17 are drawings of the anode layer (100) of FIG. 3 viewed from a third direction (D3).

[0159] For example, referring to FIG. 15, the edge region (EDG1) of the positive active material layer (120), the inorganic insulating layer (ISL1), and the first organic insulating layer (ISL2) may be located on the positive tab (CTB). The inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2) may have substantially the same length along the first direction (D1). Referring to FIGS. 4 through 8 together, the inorganic insulating layer (ISL1) may cover the edge region (EDG1) of the positive active material layer (120) and a portion of the positive tab (CTB). The first organic insulating layer (ISL2) may cover a portion of the inorganic insulating layer (ISL1) and a portion of the positive tab (CTB). For example, a portion of the positive tab (CTB) may be exposed by the inorganic insulating layer (ISL1) and the first organic insulating layer (ISL2).

[0160] As another example, referring to FIG. 16, the edge region (EDG1) of the positive active material layer (120) and the inorganic insulating layer (ISL1) may be located on the positive current collector (110) adjacent to the positive tab (CTB), and the first organic insulating layer (ISL2) may be located on the positive tab (CTB). The length along the first direction (D1) of the inorganic insulating layer (ISL1) may be greater than the length along the first direction (D1) of the first organic insulating layer (ISL2). Referring together to FIG. 4 through 8, the inorganic insulating layer (ISL1) may cover the edge region (EDG1) of the positive active material layer (120) and a portion of the positive current collector (110). The first organic insulating layer (ISL2) may cover a portion of the inorganic insulating layer (ISL1) and a portion of the positive tab (CTB). For example, a portion of the positive tab (CTB) may be exposed by the first organic insulating layer (ISL2).

[0161] As another example, referring to FIG. 17, the positive tab (CTB) may have a rounded side shape, and the edge region (EDG1) of the positive active material layer (120), the inorganic insulating layer (ISL1), and the first organic insulating layer (ISL2) may be located on the positive tab (CTB). The length along the first direction (D1) of the inorganic insulating layer (ISL1) may be substantially the same as or greater than the length along the first direction (D1) of the first organic insulating layer (ISL2). Referring together to FIG. 4 through 8, the inorganic insulating layer (ISL1) may cover the edge region (EDG1) of the positive active material layer (120) and a portion of the positive tab (CTB). The first organic insulating layer (ISL2) may cover a portion of the inorganic insulating layer (ISL1) and a portion of the positive tab (CTB). For example, a portion of the positive tab (CTB) may be exposed by an inorganic insulating layer (ISL1) and a first organic insulating layer (ISL2).

[0162]

[0163] In the embodiments described below, detailed descriptions of technical features that overlap with those previously described with reference to FIGS. 1 to 17 are omitted, and differences are described in detail.

[0164] FIGS. 18 and FIGS. 19 are each intended to illustrate an all-solid-state battery according to another embodiment of the present invention. FIG. 18 is a cross-sectional view along the line AA' of FIG. 1. FIG. 19 is a cross-sectional view along the line BB' of FIG. 1.

[0165] Referring to FIG. 18, the negative electrode layer (200) of the unit cell (CEL) according to the present embodiment may further include a lithium metal layer (400) between the negative electrode current collector (210) and the coating layer (220). The lithium metal layer (400) may be formed during the charging of the unit cell (CEL), or its thickness may be further increased. 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).

[0166] The lithium metal layer (400) may be a thin metal film containing lithium or a lithium alloy. The lithium alloy is not limited to, for example, Li-Al alloy, Li-Sn alloy, Li-In alloy, Li-Ag alloy, Li-Au alloy, Li-Zn alloy, Li-Ge alloy, Li-Si alloy, etc., and any alloy used as a lithium alloy is possible. The lithium metal layer (400) may contain one of these alloys or lithium. Alternatively, the lithium metal layer (400) may contain various types of alloys.

[0167] 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).

[0168] Referring to FIG. 19, the bi-cell all-solid-state battery (BCL) according to the present embodiment may include a first unit cell (CEL1) and a second unit cell (CEL2).

[0169] Each of the first unit cell (CEL1) and the second unit cell (CEL2) may include all the configurations of the unit cell (CEL) described above. The first unit cell (CEL1) and the second unit cell (CEL2) may be stacked so that the positive current collectors (110) are in contact with each other. The second unit cell (CEL2) may be arranged vertically symmetrically with respect to the first unit cell (CEL1).

[0170] The first unit cell (CEL1) and the second unit cell (CEL2) may further include an anti-slip film between the positive current collectors (110) so that they do not slip when stacked.

[0171] Although not illustrated, an all-solid-state battery according to another embodiment of the present invention may further include an elastic pad. The elastic pad may be a polyurethane elastomer, an acrylic elastomer, or a silicone rubber. During charging and discharging of the all-solid-state battery, a change in volume may occur due to the precipitation and dissociation of lithium (Li). The elastic pad may provide elasticity to buffer the volume expansion of the all-solid-state battery or to restore the volume of the all-solid-state battery.

[0172]

[0173] The all-solid-state battery according to the present invention can have the following effects.

[0174] The all-solid-state battery according to the present invention can prevent an electrical short circuit caused by contact between the positive electrode tab (CTB) and the negative electrode layer (200) by forming an inorganic insulating layer (ISL1) and a first organic insulating layer (ISL2) on one side (SD1) of the positive electrode active material layer (120) adjacent to the positive electrode tab (CTB). Additionally, the all-solid-state battery according to the present invention can prevent an electrical short circuit caused by contact between the negative electrode tab (ATB) and the positive electrode layer (100) by forming a second organic insulating layer (ISL3) on one side (SD4) of the coating layer (220) adjacent to the negative electrode tab (ATB). Thus, the all-solid-state battery according to the present invention can have excellent lifespan characteristics.

[0175] A gasket can generally be provided to fill the lateral step difference in a unit cell (CEL) of an all-solid-state battery as shown in FIG. 1, and can effectively insulate the positive tab (CTB) or negative tab (ATB) to prevent the problem of an internal short circuit in the cell. However, the inorganic insulating layer (ISL1), the first organic insulating layer (ISL2), and the second organic insulating layer (ISL3) of the present invention can replace the gasket to effectively insulate the positive tab (CTB) and the negative tab (ATB). In an all-solid-state battery according to the present invention, the gasket may be omitted. By omitting the gasket, the difference in area between the negative composite layer (ASH) and the positive composite layer (CSH) may be reduced. The positive composite layer (CSH) may have a relatively large area (WI1 × WI3). This allows for a reduction in the production cost of the all-solid-state battery and an improvement in the capacity and energy density of the all-solid-state battery. For example, the initial discharge capacity of an all-solid-state battery can be 412 mAh or more.

[0176]

[0177] 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.

[0178]

[0179] Example 1

[0180] (Manufacturing of the anode layer (100))

[0181] A positive electrode active material layer slurry was applied onto a positive electrode current collector (aluminum (Al) foil, thickness = 13 μm) coated with a carbon-containing layer (carbon nanotubes and binder (PVDF-HFP), binder content = 40 wt%, thickness = 1 μm) on one side, vacuum dried at 40 ℃ for 8 hours, and then subjected to a pressurization process using a roll press. As the positive electrode active material, LiNi with a specific capacity of 200 mAh / g was used. 0.8 Co 0.15 Mn 0.05O2 (NCM), Li6PS5Cl (D50 = 0.5 μm, crystalline), an argyrodite-type crystal, as the solid electrolyte, carbon nanofibers (CNF) as the conductive material, and polytetrafluoroethylene (PTFE) as the binder were prepared. The cathode active material layer slurry was mixed with xylene solvent at a weight ratio of cathode active material : solid electrolyte : conductive material : binder = 85 : 11.5 : 3 : 1.5. The cathode active material layer slurry had a concentration of 25.4 mg / cm². 2 It was applied on the positive current collector (110) to have a loading level. The thickness of the positive active material layer (120) was 107 μm, and the current density was 4.3 mAh / cm². 2 It was. The positive active material layer (120) included an edge region (EDG1), and the length (d) of the edge region (EDG1) in the second direction EDG1 ) was 1mm.

[0182] An inorganic insulating layer (ISL1) was formed by applying and drying an inorganic insulating layer composition on one side (SD1) of the positive active material layer (120). The inorganic insulating layer (ISL1) contained AlOOH as an inorganic material and PVDF-HFP with an HFP content of 30 wt% as a binder in a weight ratio of 7.5:2.5. The inorganic insulating layer (ISL1) was formed such that the horizontal distance (d12) from the first end (ED1) to the second end (ED2) was 1.5 mm.

[0183] A first organic insulating layer (ISL2) was formed by applying and drying a first organic insulating layer slurry on one side (SD2) of an inorganic insulating layer (ISL1). The first organic insulating layer (ISL2) contained polyamideimide. The first organic insulating layer (ISL2) was formed such that the horizontal distance (d13) from the first end (ED1) to the third end (ED3) was 4.5 mm, and the horizontal distance (d14) from the first end (ED1) to the fourth end (ED4) was 0.5 mm.

[0184] (Manufacturing of the anode composite layer (CSH))

[0185] A mixture was prepared by adding a polyacrylate (SX-A334, Zeon) binder and a BYK dispersant to an argyrodite-type crystal Li6PS5Cl sulfide-based solid electrolyte (D50 = 3.0 μm, crystalline) (weight ratio of solid electrolyte : binder : dispersant = 94.4 : 5 : 0.6). A solid electrolyte layer slurry was prepared by stirring while adding octyl acetate to the prepared mixture.

[0186] The prepared solid electrolyte layer slurry was applied onto a temporary substrate (aluminum (Al) foil) using a blade coater and dried. After pressurization, the solid electrolyte layer had a thickness of 10 µm to 80 µm and a g / cm³ 3 A solid electrolyte layer was formed on a temporary substrate by performing a pressurization process using a roll press to have the density.

[0187] By the above process, a first solid electrolyte layer (310) having substantially the same area as the anode layer (100) and a second solid electrolyte layer (320) having substantially the same area as the cathode layer (200) were each prepared.

[0188] The first solid electrolyte layer (310) and a temporary substrate were laminated on the anode layer (100) so that the first solid electrolyte layer (310) was in contact with the anode active material layer (120), and a pressurizing process was performed using a roll press to laminate the anode layer (100) and the first solid electrolyte layer (310). Afterward, the temporary substrate was removed. In other words, the first solid electrolyte layer (310) was transferred onto the anode active material layer (120). The pressurizing process was performed at a temperature of 120°C and a linear pressure of 3.5 ton / cm after preheating with infrared (IR) at a temperature of 140°C.

[0189] (Manufacturing of the negative electrode layer (200))

[0190] A coating layer slurry was applied onto a cathode current collector (Ni-plated Cu(Ni-Cu), thickness = 10 μm) using a bar coater, dried in air at 80°C for 10 minutes, dried under vacuum at 40°C for 10 hours, and then subjected to a pressurization process using a roll press. The coating layer slurry was prepared by placing 4 g of a mixed powder, consisting of silver (Ag) particles (average particle size 60 nm) and carbon black mixed in a weight ratio of 3:1, into a container, adding 4 g of an NMP solution containing 7 wt% PVDF binder (Kureha # 9300), and then stirring while gradually adding the NMP solution to the mixed solution. The coating layer slurry had a density of 0.8 mg / cm² 2 It was applied onto the negative current collector (210) to have a loading level. The pressurization process was performed at a temperature of 25°C with a linear pressure of 1.5 ton / cm to flatten the surface of the coating layer (220). The thickness of the coating layer (220) was 7 μm. The area of ​​the coating layer (220) was larger than the area of ​​the positive active material layer (120).

[0191] A second organic insulating layer (ISL3) was formed by applying and drying a second organic insulating layer slurry on one side (SD4) of the coating layer (220). The second organic insulating layer (ISL3) contained polyamideimide. The second organic insulating layer (ISL3) was formed such that the horizontal distance (d57) from the fifth end (ED5) to the seventh end (ED7) was 2 mm, and the horizontal distance (d56) from the fifth end (ED5) to the sixth end (ED6) was 1 mm.

[0192] (Manufacturing of cathode composite layer (ASH))

[0193] The second solid electrolyte layer (320) and a temporary substrate were laminated on the cathode layer (200) such that the exposed surface of the second solid electrolyte layer (320) was in contact with the coating layer (220), and a pressurizing process was performed using a roll press to laminate the cathode layer (200) and the second solid electrolyte layer (320). Afterward, the temporary substrate was removed. In other words, the second solid electrolyte layer (320) was transferred onto the coating layer (220). The pressurizing process was performed at a temperature of 120°C and a linear pressure of 3.0 ton / cm after preheating with infrared (IR) at a temperature of 140°C.

[0194] (Manufacturing of all-solid-state batteries)

[0195] An anode composite layer (CSH) was laminated on a cathode composite layer (ASH), and a pressurizing process was performed using a roll press. The pressurizing process was performed at a temperature of 160°C and a linear pressure of 0.5 ton / cm. Thus, an all-solid-state battery was manufactured.

[0196] The all-solid-state battery had the structure shown in FIGS. 1 to 3. The area (WI1 × WI3) of the positive electrode composite layer (CSH) was 95 cm² 2 inner 98cm 2 The difference between the second width (WI2) and the first width (WI1) was 1 mm. The difference between the fourth width (WI4) and the third width (WI3) was 2 mm. The inorganic insulating layer (ISL1) covered the entire side (SD1) of the positive active material layer (120). The first organic insulating layer (ISL2) covered a portion of the side (SD2) of the inorganic insulating layer (ISL1). The second organic insulating layer (ISL3) covered the entire side (SD4) of the coating layer (220) and covered a portion of the upper surface of the central region (CTR2) of the coating layer (220).

[0197]

[0198] Example 2

[0199] The first organic insulating layer (ISL2) was manufactured in the same manner as in Example 1, except that the horizontal distance (d13) from the first end (ED1) to the third end (ED3) is 2 mm. The inorganic insulating layer (ISL1) completely covered one side (SD1) of the positive active material layer (120). The first organic insulating layer (ISL2) covered a portion of one side (SD2) of the inorganic insulating layer (ISL1). The second organic insulating layer (ISL3) completely covered one side (SD4) of the coating layer (220) and covered a portion of the upper surface of the central region (CTR2) of the coating layer (220).

[0200]

[0201] Example 3

[0202] The first organic insulating layer (ISL2) was manufactured in the same manner as in Example 1, except that the horizontal distance (d13) from the first end (ED1) to the third end (ED3) is 9 mm. The inorganic insulating layer (ISL1) completely covered one side (SD1) of the positive active material layer (120). The first organic insulating layer (ISL2) covered a portion of one side (SD2) of the inorganic insulating layer (ISL1). The second organic insulating layer (ISL3) completely covered one side (SD4) of the coating layer (220) and covered a portion of the upper surface of the central region (CTR2) of the coating layer (220).

[0203]

[0204] Example 4

[0205] The inorganic insulating layer (ISL1) was manufactured in the same manner as in Example 1, except that the horizontal distance (d12) from the first end (ED1) to the second end (ED2) is 2.7 mm. The inorganic insulating layer (ISL1) completely covers one side (SD1) of the positive active material layer (120), and the inorganic insulating layer (ISL1) covers a portion of the upper surface of the positive active material layer (120). The first organic insulating layer (ISL2) covers a portion of one side (SD2) of the inorganic insulating layer (ISL1). The second organic insulating layer (ISL3) completely covers one side (SD4) of the coating layer (220) and covers a portion of the upper surface of the central region (CTR2) of the coating layer (220).

[0206]

[0207] Example 5

[0208] The second organic insulating layer (ISL3) was manufactured in the same manner as in Example 1, except that the horizontal distance (d57) from the fifth end (ED5) to the seventh end (ED7) is 2.7 mm. The inorganic insulating layer (ISL1) completely covered one side (SD1) of the positive active material layer (120). The first organic insulating layer (ISL2) covered a portion of one side (SD2) of the inorganic insulating layer (ISL1). The second organic insulating layer (ISL3) completely covered one side (SD4) of the coating layer (220) and covered a portion of the upper surface of the central region (CTR2) of the coating layer (220).

[0209]

[0210] Example 6

[0211] The second organic insulating layer (ISL3) was manufactured in the same manner as in Example 1, except that the horizontal distance (d56) from the fifth end (ED5) to the sixth end (ED6) is 0.3 mm. The inorganic insulating layer (ISL1) completely covered one side (SD1) of the positive active material layer (120). The first organic insulating layer (ISL2) covered a portion of one side (SD2) of the inorganic insulating layer (ISL1). The second organic insulating layer (ISL3) completely covered one side (SD4) of the coating layer (220) and covered a portion of the upper surface of the central region (CTR2) of the coating layer (220).

[0212]

[0213] Example 7

[0214] The second organic insulating layer (ISL3) was manufactured in the same manner as in Example 1, except that the horizontal distance (d56) from the fifth end (ED5) to the sixth end (ED6) is 4.4 mm. The inorganic insulating layer (ISL1) completely covered one side (SD1) of the positive active material layer (120). The first organic insulating layer (ISL2) covered a portion of one side (SD2) of the inorganic insulating layer (ISL1). The second organic insulating layer (ISL3) completely covered one side (SD4) of the coating layer (220) and covered a portion of the upper surface of the central region (CTR2) of the coating layer (220).

[0215]

[0216] Comparative Example 1

[0217] An anode composite layer (CSH) that does not contain any inorganic insulating layer (ISL1) or first organic insulating layer (ISL2), and a cathode composite layer (ASH) that does not contain any second organic insulating layer (ISL3) were prepared. To apply a gasket, the area (WI1 × WI3) of the anode composite layer (CSH) is 85.6 cm². 2The difference between the second width (WI2) and the first width (WI1) was 5.6 mm, and the difference between the fourth width (WI4) and the third width (WI3) was 5.6 mm. A gasket was attached to the cathode composite layer (ASH). The anode composite layer (CSH) was laminated on the cathode composite layer (ASH) so that the gasket surrounded the anode composite layer (CSH), and a pressurizing process was performed using a roll press. The thickness of the gasket in the third direction was the same as the thickness of the anode composite layer (CSH) in the third direction. There was a gap of 0.8 mm between the anode composite layer (CSH) and the gasket.

[0218] Thus, an all-solid-state battery was manufactured by applying a gasket instead of an inorganic insulating layer (ISL1), a first organic insulating layer (ISL2), and a second organic insulating layer (ISL3).

[0219]

[0220] Comparative Example 2

[0221] It was manufactured in the same manner as Example 1, except that it does not contain an inorganic insulating layer (ISL1), a first organic insulating layer (ISL2), and a second organic insulating layer (ISL3).

[0222]

[0223] Experimental Example: Evaluation of Initial Capacity and Short Circuit Occurrence Time of All-Solid State Battery

[0224] The initial capacity and the time of short circuit occurrence of the all-solid-state battery according to the examples and comparative examples were evaluated. The evaluation of the initial capacity and the time of short circuit occurrence was performed by placing elastic pads (polyurethane foam, thickness = 300 μm) having the same surface area as the all-solid-state battery on the upper and lower surfaces of the all-solid-state battery, respectively, placing them in a pouch, and sealing them. The evaluation of the initial capacity and the time of short circuit occurrence was performed by placing the all-solid-state battery in a constant temperature bath at 45°.

[0225] The initial capacity evaluation was performed as follows. The battery was charged with a constant current of 0.1C until the battery voltage reached 4.25V, and upon reaching 4.25V, constant voltage charging was performed at 4.25V under a 0.05C cut-off condition. Subsequently, the battery was discharged with a constant current of 1.0C until the battery voltage reached 2.5V. At this time, the discharge capacity was set as the initial capacity.

[0226] The short-circuit occurrence point evaluation was performed as follows. In the first cycle, the battery was charged with a constant current of 0.33C until the battery voltage reached 4.25V, and upon reaching 4.25V, constant voltage charging was performed at 4.25V under a 0.1C cut-off condition. Subsequently, the battery was discharged with a constant current of 0.33C until the battery voltage reached 2.5V. From the second cycle onwards, charging and discharging were performed for up to 350 cycles under the same conditions as the first cycle. This implies that the life characteristics improve as the number of cycles at which a short circuit occurs increases. A short circuit was confirmed to have occurred using the standard method (charge amount during life = discharge amount × 10%), and the number of cycles at that time was recorded.

[0227] The results are shown in Table 1.

[0228]

[0229] Classification Initial Capacity (mAh) Short-circuit Occurrence Time (Number of Cycles) Example 1 4 14 > 200 Example 2 4 14 > 200 Example 3 4 14 > 200 Example 4 4 ​​0 5 > 300 Example 5 4 11 > 200 Example 6 4 14 > 200 Example 7 4 14 > 200 Comparative Example 1 3 6 8 < 100 Comparative Example 2 4 2 1 < 10”>n” means that no short circuit occurred even after n cycle tests. <n”은, n회 사이클 시험 동안 단락이 발생함을 의미함.

[0230]

[0231] Referring to Table 1, the all-solid-state batteries according to Examples 1 to 7 had an initial capacity improved by 12.5% ​​compared to the all-solid-state battery according to Comparative Example 1, and had a longer lifespan because the time of occurrence of a short circuit was later. The all-solid-state batteries according to Examples 1 to 7 had a longer lifespan because the time of occurrence of a short circuit was later than that of the all-solid-state battery according to Comparative Example 1 and the all-solid-state battery according to Comparative Example 2.

[0232] Thus, it was confirmed that the all-solid-state battery according to Examples 1 to 7 can reduce the difference in area between the negative electrode composite layer and the positive electrode composite layer by omitting the gasket, and increase the initial capacity. In addition, it was confirmed that the all-solid-state battery according to Examples 1 to 7 has a long lifespan by preventing electrical short circuits through the inorganic insulating layer, the first organic insulating layer, and the second organic insulating layer.

[0233] On the other hand, in Comparative Example 1, due to the presence of a gap between the anode composite layer and the gasket, there is a region in the second solid electrolyte layer between the cathode composite layer and the anode composite layer that is not sufficiently pressurized when a pressurization process is performed on the anode composite layer and the cathode composite layer, and it was confirmed that the lifespan is short due to the deterioration of the region that is not sufficiently pressurized. In Comparative Example 2, due to the step difference on the side caused by the difference in area between the cathode composite layer and the anode composite layer, there is a region in the second solid electrolyte layer that is not sufficiently pressurized when a pressurization process is performed on the anode composite layer and the cathode composite layer, and the lifespan is very short due to the deterioration of the region that is not sufficiently pressurized.

[0234] Meanwhile, the all-solid-state batteries according to Examples 1 to 3, 6, and 7 had a larger initial capacity than the all-solid-state batteries according to Examples 4 and 5. Thus, it was confirmed that the all-solid-state batteries according to Examples 1 to 3, 6, and 7 can have an excellent initial capacity of 412 mAh or more by including an inorganic insulating layer, a first organic insulating layer, and a second organic insulating layer having appropriate lengths.

[0235]

[0236] 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. An anode layer comprising an anode current collector and an anode active material layer on the anode current collector; A cathode layer comprising a cathode current collector and a coating layer on the cathode current collector; and It includes a solid electrolyte layer between the anode layer and the cathode layer, The anode layer further comprises an inorganic insulating layer and a first organic insulating layer on one side of the anode active material layer, and The above cathode layer further comprises a second organic insulating layer on one side of the coating layer, All-solid-state battery.

2. In Paragraph 1, One side of the above positive active material layer is adjacent to the positive tab of the above positive current collector, and One side of the coating layer is adjacent to the cathode tab of the cathode current collector, All-solid-state battery.

3. In Paragraph 1, The above inorganic insulating layer and the above first organic insulating layer are adjacent to the positive tab of the positive current collector than the positive active material layer, and The second organic insulating layer is adjacent to the cathode tab of the cathode current collector than the coating layer, All-solid-state battery.

4. In Paragraph 1, The above inorganic insulating layer is located between the anode active material layer and the first organic insulating layer, All-solid-state battery.

5. In Paragraph 1, The above inorganic insulating layer covers at least a portion of the above-mentioned side of the anode active material layer, All-solid-state battery.

6. In Paragraph 1, The first organic insulating layer covers at least a portion of one side of the inorganic insulating layer, All-solid-state battery.

7. In Paragraph 1, A portion of the anode tab of the anode current collector is exposed by the inorganic insulating layer and the first organic insulating layer, All-solid-state battery.

8. In Paragraph 1, The second organic insulating layer covers at least a portion of the one side of the coating layer, All-solid-state battery.

9. In Paragraph 1, The second organic insulating layer covers a portion of the upper surface of the coating layer. All-solid-state battery.

10. In Paragraph 1, A portion of the cathode tab of the above-mentioned cathode current collector is exposed by the second organic insulating layer, All-solid-state battery.

11. In Paragraph 1, The above-mentioned inorganic insulating layer comprises at least one of an inorganic material or a binder, and The above inorganic material comprises at least one selected from the group consisting of Al2O3, Al(OH)3, AlOOH, SiO2, MgO, TiO2, SnO2, and ZnO, and The binder comprises at least one selected from the group consisting of vinylidene fluoride / hexafluoropropylene copolymer, polyacrylate, polyvinylidenefluoride, styrene butadiene rubber, polytetrafluoroethylene, polyacrylonitrile, and polymethyl methacrylate. All-solid-state battery.

12. In Paragraph 1, The above inorganic insulating layer comprises an inorganic material and a binder in a weight ratio of 5:5 to 8:2, All-solid-state battery.

13. In Paragraph 1, The first organic insulating layer and the second organic insulating layer comprise at least one selected from the group consisting of polyamideimide, polyimide, polysulfone, polyurethane, polycarbonate, epoxy resin, polysulfide, and polybenzimidazole. All-solid-state battery.

14. In Paragraph 1, The above all-solid-state battery is one in which the gasket is omitted, All-solid-state battery.

15. In Paragraph 1, The above solid electrolyte layer comprises a first solid electrolyte layer adjacent to the anode layer and a second solid electrolyte layer adjacent to the cathode layer, and The above anode layer and the above first solid electrolyte layer constitute an anode composite layer, and The above cathode layer and the above second solid electrolyte layer constitute a cathode composite layer, and The area of ​​the above cathode composite layer is larger than the area of ​​the above anode composite layer, All-solid-state battery.

16. Forming an anode composite layer comprising an anode layer and a first solid electrolyte layer; Forming a cathode composite layer comprising a cathode layer and a second solid electrolyte layer; and A method comprising forming an all-solid-state battery by stacking the anode composite layer on the cathode composite layer, wherein Forming the anode composite layer comprises forming an inorganic insulating layer and a first organic insulating layer on one side of the anode active material layer of the anode layer, and Forming the above cathode composite layer includes forming a second organic insulating layer on one side of the coating layer of the above cathode layer. Method for manufacturing an all-solid-state battery.

17. In Paragraph 16, The above inorganic insulating layer is located between the anode active material layer and the first organic insulating layer, Method for manufacturing an all-solid-state battery.

18. In Paragraph 16, The above inorganic insulating layer covers at least a portion of the above-mentioned side of the anode active material layer, Method for manufacturing an all-solid-state battery.

19. In Paragraph 16, The first organic insulating layer covers at least a portion of one side of the inorganic insulating layer, Method for manufacturing an all-solid-state battery.

20. In Paragraph 16, The second organic insulating layer covers at least a portion of the one side of the coating layer, Method for manufacturing an all-solid-state battery.

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