All-solid-state battery and method of manufacturing same

Abstract

The present invention relates to an all-solid-state battery and a method of manufacturing same. More specifically, the method comprises: preparing a first negative electrode layer; preparing a first positive electrode layer; preparing a solid electrolyte membrane; forming a first folding portion and a second folding portion in the solid electrolyte membrane; positioning the first negative electrode layer adjacent to the first folding portion; positioning the first positive electrode layer adjacent to the second folding portion; and bringing the first positive electrode layer, the first negative electrode layer, and the solid electrolyte membrane into contact with one another.

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] Recent industrial demands have led to the active development of batteries with high energy density and safety. For example, lithium-ion batteries are being used not only in information and communication devices, but also in the automotive sector. Safety is particularly important in the automotive sector, as it is directly related to life.

[0003] Recently, all-solid-state batteries, which replace the electrolyte with a solid electrolyte, have been proposed. By eliminating the use of flammable organic dispersion media, all-solid-state batteries significantly reduce the risk of fire or explosion in the event of a short circuit. Therefore, these all-solid-state batteries can significantly improve safety compared to lithium-ion batteries that use electrolytes.

[0004] The problem to be solved by the present invention is to provide a method for manufacturing an all-solid-state battery that is easy to manufacture and capable of continuous production.

[0005] Another problem to be solved by the present invention is to provide an all-solid-state battery having high capacity and / or energy density.

[0006] A method for manufacturing an all-solid-state battery according to one embodiment of the present invention may include: preparing a first negative electrode layer including a pair of negative electrode active material layers and a negative electrode current collector between the pair of negative electrode active material layers; preparing a first positive electrode layer including a pair of positive electrode active material layers and a positive electrode current collector between the pair of positive electrode active material layers; preparing a solid electrolyte membrane including a first portion, a second portion, and a third portion that are positioned horizontally side by side; forming a first folding portion between the first portion and the second portion, and a second folding portion between the second portion and the third portion; providing the first negative electrode layer between the first portion and the second portion, so that the first negative electrode layer is adjacent to the first folding portion; providing the first positive electrode layer between the second portion and the third portion, so that the first positive electrode layer is adjacent to the second folding portion; and bringing the first positive electrode layer, the first negative electrode layer, and the solid electrolyte membrane into contact with each other.

[0007] An all-solid-state battery according to one embodiment of the present invention comprises: a first positive electrode layer including a pair of positive electrode active material layers and a positive electrode current collector between the pair of positive electrode active material layers; a first negative electrode layer disposed on the first positive electrode layer and including a pair of negative electrode active material layers and a negative electrode current collector between the pair of negative electrode active material layers; and a solid electrolyte layer including a first horizontal portion, a first vertical portion, a second horizontal portion, a second vertical portion, and a third horizontal portion; Including, the first vertical portion connects the first horizontal portion and the second horizontal portion to each other, the second vertical portion connects the second horizontal portion and the third horizontal portion to each other, the first cathode layer is interposed between the first horizontal portion and the second horizontal portion, the first anode layer is interposed between the second horizontal portion and the third horizontal portion, the first cathode layer includes a first side and a second side which face each other in a first direction, the first anode layer includes a third side and a fourth side which face each other in the first direction, the second side is exposed from the solid electrolyte layer, and the third side can be exposed from the solid electrolyte layer.

[0008] By using a method for manufacturing an all-solid-state battery according to one embodiment of the present invention, an all-solid-state battery can be manufactured more easily and the productivity of the all-solid-state battery can be improved.

[0009] Additionally, the all-solid-state battery according to one embodiment of the present invention may have excellent capacity and / or energy density.

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

[0011] FIG. 2 is a cross-sectional view of an all-solid-state battery including a gasket according to embodiments of the present invention.

[0012] Figure 3 is a flowchart of a method for manufacturing an all-solid-state battery according to embodiments of the present invention.

[0013] FIGS. 4 to 9 are each cross-sectional views illustrating a method for manufacturing an all-solid-state battery according to embodiments of the present invention.

[0014] Figure 10 is a cross-sectional view of an all-solid-state battery manufactured using a manufacturing method according to one embodiment of the present invention.

[0015] FIG. 11a is a cross-sectional view of an all-solid-state battery including a composite material manufactured using a manufacturing method according to one embodiment of the present invention.

[0016] Figure 11b is a cross-sectional view for explaining a composite material.

[0017] FIG. 12 is a cross-sectional view of an all-solid-state battery including a gasket manufactured using a manufacturing method according to one embodiment of the present invention.

[0018] To fully understand the structure and effects of the present invention, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various forms and subject to various modifications. However, the description of these embodiments is provided solely to ensure a complete disclosure of the present invention and to fully inform those skilled in the art of the invention of the scope of the invention.

[0019] In this specification, when a component is referred to as being on another component, it means that it can be formed directly on the other component, or a third component may be interposed between them. Furthermore, in the drawings, the thicknesses of the components are exaggerated for the sake of clarity. Parts designated by the same reference numerals throughout the specification represent the same components.

[0020] Embodiments described herein will be described with reference to cross-sectional and / or plan views, which are ideal illustrations of the present invention. In the drawings, the thicknesses of films and regions are exaggerated for the purpose of effectively explaining the technical contents. Accordingly, the regions illustrated in the drawings have a schematic nature, and the shapes of the regions illustrated in the drawings are intended to illustrate specific shapes of regions of the device and are not intended to limit the scope of the invention. Although terms such as first, second, and third are used to describe various components in various embodiments of the present specification, these components should not be limited by such terms. These terms are used only to distinguish one component from another. The embodiments described and illustrated herein also include complementary embodiments thereof.

[0021] The terminology used herein is for the purpose of describing embodiments and is not intended to limit the present invention. In this specification, the singular also includes the plural unless specifically stated otherwise. As used herein, the words "comprises" and / or "comprising" do not exclude the presence or addition of one or more other components.

[0022]

[0023] FIG. 1 is a cross-sectional view of an all-solid-state battery according to embodiments of the present invention. FIG. 2 is a cross-sectional view of an all-solid-state battery including a gasket according to embodiments of the present invention.

[0024] Referring to FIG. 1, an all-solid-state battery according to one embodiment includes a positive electrode layer (100), a negative electrode layer (200) facing the positive electrode layer (100), and a solid electrolyte layer (300) disposed between the positive electrode layer (100) and the negative electrode layer (200). However, the all-solid-state battery is not limited thereto, and 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).

[0025] The positive electrode layer (100) of one embodiment includes a positive electrode current collector (110) and a positive electrode active material layer (120) disposed on the positive electrode current collector (110). The positive electrode active material layer (120) may include a positive electrode active material, a solid electrolyte, a conductive material, and a binder.

[0026] The cathode current collector (110) can provide a reference surface on which the cathode active material layer (120) is arranged. The cathode current collector (110) can include a plate or foil including, for example, 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.

[0027] Meanwhile, unlike that illustrated in FIG. 1, in one embodiment of the present invention, the positive electrode current collector (110) may be omitted. Although not illustrated, a carbon layer having a thickness of 0.1 μm to 4 μm may be additionally disposed between the positive electrode current collector (110) and the positive electrode active material layer (120) to increase the bonding strength between the positive electrode current collector (110) and the positive electrode active material layer (120).

[0028] A cathode active material is a material that can reversibly absorb and desorb lithium ions. The cathode active material may include, but is not necessarily limited to, 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. The cathode active materials may be used alone or as a mixture of two or more.

[0029] Lithium transition metal oxides include, for example, Li a A 1-b B b D2(0.90≤a≤1, 0≤b≤0.5), Li a E 1-b B b O 2-c D c (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05), LiE 2-b B b O 4-c D c (0≤b≤0.5, 0≤c≤0.05), Li a Ni 1-b-c Co b B c D α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α<2), Li a Ni 1-b-c Co b B c O 2-α F α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α<2), Li a Ni 1-b-c Mn b B c D α(0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α≤2), Li a Nor 1-b-c Mn b B c O 2-α F α (0.90≤a≤1, 0≤b≤0.5, 0≤c≤0.05, 0<α<2), Li a Nor b E c G d O2(0.90≤a≤1, 0≤b≤0.9, 0≤c≤0.5, 0.001≤d≤0.1), Li a Nor b Co c Mn d GeO2(0.90≤a≤1, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0.001≤e≤0.1), Li a NiG b O2(0.9≤a≤1, 0.001≤b≤0.1), Li a CoG b O2(0.90≤a≤1, 0.001≤b≤0.1), Li a MnG b O2(0.90≤a≤1, 0.001≤b≤0.1), Li a Mn2GbO4(0.90≤a≤1, 0.001≤b≤0.1), QO2, QS2, LiQS2, V2O5, LiV2O5, LiIO2, LiNiVO4, Li 3-f J2(PO4)3(0≤f≤2), Li 3-fA compound represented by any one of Fe2(PO4)3(0≤f≤2), LiFePO4. In these compounds, the capital letter “A” is Ni, Co, Mn, or a combination thereof, the capital letter “B” is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element, or a combination thereof, the capital letter “D” is O, F, S, P, or a combination thereof, the capital letter “E” is Co, Mn, or a combination thereof, the capital letter “F” is F, S, P, or a combination thereof, the capital letter “G” is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof, the capital letter “Q” is Ti, Mo, Mn, or a combination thereof, the capital letter “I” is Cr, V, Fe, Sc, Y, or a combination thereof, and the capital letter “J” is V, Cr, Mn, Co, Ni, Cu, or a combination thereof.

[0030] The cathode active material may include, for example, a lithium salt of a transition metal oxide having a layered rock salt type structure among the lithium transition metal oxides described above. The "layered rock salt type structure" is, for example, a cubic rock salt type structure. <111> It is a structure in which oxygen atomic layers and metal atomic layers are alternately and regularly arranged in a direction, and thereby each atomic layer forms a two-dimensional plane. The "cubic rock salt structure" refers to the sodium chloride type (NaCl type) structure, which is a type of crystal structure, and specifically refers to a structure in which the face-centered cubic lattice (fcc) formed by each cation and anion is arranged with a displacement of half of the ridge of the unit lattice. Lithium transition metal oxides having this layered rock salt structure include, for example, LiNi x Co y Al z O2(NCA) or LiNi x Co y Mn zO2(NCM) (0 <x<1,0<y<1, 0<z<1, x+y+z=1) 등의 삼원계 리튬전이금속산화물일 수 있다. 양극활물질이 층상암염형 구조를 갖는 삼원계 리튬전이금속산화물을 포함하는 경우, 전고체 전지의 에너지 밀도가 커지고 열안정성이 향상될 수 있다.

[0031] The above-described compound included 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 above-described compound and a compound to which a coating layer is added. Meanwhile, the coating layer added to the surface of the positive electrode active material may include, for example, an oxide, a hydroxide, an oxyhydroxide, an oxycarbonate, or a hydroxycarbonate of the coating elements below. The compound forming the coating layer may be 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 of 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 of forming the coating layer includes, for example, spray coating, dipping, etc.

[0032] When the cathode active material is a ternary lithium transition metal oxide such as NCA or NCM that contains nickel (Ni), the capacity density of the all-solid-state battery can be increased, thereby reducing metal dissolution of the cathode active material in a charged state. As a result, the cycle characteristics of the all-solid-state battery in a charged state are improved. Meanwhile, the “cycle characteristics” are characteristics that indicate the degree to which the all-solid-state battery is deteriorated due to charge / discharge of the all-solid-state battery. An all-solid-state battery with high cycle characteristics may be deteriorated less due to charge / discharge, and an all-solid-state battery with low cycle characteristics may be deteriorated more due to charge / discharge.

[0033] The shape of the cathode active material may include particle shapes such as a sphere or an ellipsoid, for example. The particle size and content of the cathode active material are not particularly limited.

[0034] The solid electrolyte may include a sulfide-based solid electrolyte having excellent lithium ion conductivity characteristics. Examples of the sulfide-based solid electrolyte include Li2S-P2S5, Li2S-P2S5-LiX (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, capital letter “Z” represents Ge, Zn or Ga), Li2S-GeS2, Li2S-SiS2-Li3PO4, Li2S-SiS2-Li p MO q (p, q are positive numbers, capital letter “M” is one of P, Si, Ge, B, Al, Ga In), Li 7-x PS 6-x Cl x (0≤x≤2), Li 7-x PS 6-x Br x (0≤x≤2), and Li 7-x PS 6-x I x It may include at least one selected from (0≤x≤2).

[0035] Sulfide-based solid electrolytes include, for example, Li 7-x PS 6-x Cl x (0≤x≤2), Li 7-x PS 6-x Br x (0≤x≤2), and Li 7-x PS 6-x I xIt may be an argyrodite-type compound including at least one selected from (0≤x≤2). In particular, the sulfide-based solid electrolyte may be an argyrodite-type compound including at least one selected from Li6PS5Cl, Li6PS5Br, and Li6PS5I.

[0036] Alternatively, the sulfide-based solid electrolyte is Li 7-a M a PS 6-c X c It may be an argyrodite-type compound containing (0≤a≤2, (0≤c≤2)), where X may be F, Br, Cl, or a combination thereof. M is candium (Sc), yttrium (Y), titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), technetium (Tc), rhenium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), zinc (Zn), cadmium (Cd), mercury (Hg), aluminum (Al), gallium (Ga), indium (In), thallium (Tl), silicon (Si), germanium (Ge), tin (Sn), lead (Pb), arsenic (As), antimony (Sb), bismuth (Bi), or a combination thereof. Can be.

[0037] The density of the argyrodite-type solid electrolyte may be 1.5 g / cc to 2.0 g / cc. Since the argyrodite-type solid electrolyte has a density of 1.5 g / cc or more, the internal resistance of the all-solid-state battery is reduced, and the defect of the solid electrolyte membrane being penetrated and short-circuited due to the formation of lithium dendrites can be prevented. The elastic modulus of the solid electrolyte may be, for example, 15 GPa to 35 GPa.

[0038] The solid electrolyte included in the positive electrode active material layer (120) may have a smaller median particle size (D50) than the solid electrolyte included in the solid electrolyte layer (300). For example, the median particle size (D50) of the solid electrolyte included in the positive electrode active material layer (120) may be 90% or less, 80% or less, 70% or less, 60% or less, 50% or less, 40% or less, 30% or less, or 20% or less of the median particle size (D50) of the solid electrolyte included in the solid electrolyte layer (300). Meanwhile, the median particle size (D50) may be a median diameter measured using a laser particle size distribution meter.

[0039] The cathode active material layer (120) may include a conductive material. The conductive material may be conductive without causing chemical changes in the all-solid-state battery, thereby increasing the conductivity of the cathode active material and the solid electrolyte. The conductive material may include a carbon-based material. For example, the conductive material may include one or more selected from graphite, carbon black, acetylene black, carbon nanofibers, and carbon nanotubes.

[0040] The positive electrode active material layer (120) may further include a binder. The binder may include a material for binding the positive electrode active material, solid electrolyte, and conductive material included in the positive electrode active material layer (120) and improving bonding strength with the positive electrode current collector (110). The binder may include, for example, polyvinylidene fluoride, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, vinylidene fluoride / hexafluoropropylene copolymer, polyacrylonitrile, and polymethyl methacrylate.

[0041] Based on 100 parts by weight of the total of the positive electrode active material, the solid electrolyte, the conductive material, and the binder, the positive electrode active material layer (120) may include 75 parts by weight or more and 92 parts by weight or less of the positive electrode active material. Based on 100 parts by weight of the total of the positive electrode active material, the solid electrolyte, the conductive material, and the binder, the positive electrode active material layer (120) may include 1.0 parts by weight or more and 4.0 parts by weight or less of the binder.

[0042] Based on 100 parts by weight of the solid electrolyte, the positive electrode active material layer (120) may include 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 electrode active material layer (120) in an amount of less than 1 part by weight based on 100 parts by weight of the solid electrolyte, the proportion of the conductive material may decrease, thereby lowering the electrical conductivity of the positive electrode active material layer (120). If the conductive material is included in the positive electrode active material layer (120) in an amount of more than 50 parts by weight based on 100 parts by weight of the solid electrolyte, the proportion of the conductive material may be excessively high, so that a covering layer covering the surface of the solid electrolyte may not be properly formed.

[0043] The cathode active material layer (120) may further include additives such as fillers, coating agents, dispersants, and ion conductive aids in addition to the cathode active material, solid electrolyte, conductive agent, and binder described above.

[0044] The negative electrode layer (200) includes a negative electrode current collector (210) and a negative electrode active material layer (220) disposed on the negative electrode current collector (210). The negative electrode active material layer (220) may include a negative electrode active material and a binder.

[0045] The negative electrode current collector (210) can provide a reference surface on which the negative electrode active material layer (220) is arranged. The negative electrode current collector (210) can include, for example, a material that does not react with lithium, i.e., does not form an alloy or compound with lithium. The material constituting the negative electrode current collector (210) is not necessarily limited to, for example, copper (Cu), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), and nickel (Ni), and any material that can be used as an electrode current collector can be used. The thickness of the negative electrode current collector can be 1 to 20 μm, for example, 5 to 15 μm, for example, 7 to 10 μm.

[0046] The negative electrode current collector (210) may be composed of one of the above-described metals, or may include an alloy or coating material of two or more metals. The negative electrode current collector (210) is, for example, in the form of a plate or foil. Meanwhile, in one embodiment, the negative electrode current collector (210) may be omitted.

[0047] The negative electrode active material included in the negative electrode active material layer (220) may have a particle form. The median particle size average particle diameter (D50) of the negative electrode active material having a particle form may be, for example, 4 μm or less, 2 μm or less, 1 μm or less, or 900 nm or less. The median particle size average particle diameter (D50) of the negative electrode active material may be, for example, 10 nm to 4 μm, 10 nm to 2 μm, or 10 nm to 900 nm. When the negative electrode active material has a median particle size average diameter (D50) in this range, reversible absorption and / or desorption of lithium may be facilitated during charge and discharge. Meanwhile, the median particle size average diameter (D50) may be a median diameter measured using a laser particle size distribution meter.

[0048] The negative electrode active material may include, for example, at least one selected from a carbon-based negative electrode active material and a metal or metalloid negative electrode active material.

[0049] The carbon-based negative electrode active material may be amorphous carbon, in particular. Examples of amorphous carbon include, but are not limited to, carbon black (CB), acetylene black (AB), furnace black (FB), ketjen black (KB), and graphene. Amorphous carbon is carbon that has no crystallinity or very low crystallinity, and is distinguished from crystalline carbon or graphitic carbon.

[0050] The metal or metalloid negative electrode active material includes, but is not necessarily limited to, one or more 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), and may be a metal negative electrode active material or a metalloid negative electrode active material that forms an alloy or compound with lithium. On the other hand, nickel (Ni) does not form an alloy with lithium and therefore is not a metal negative electrode active material.

[0051] The negative electrode active material layer (220) includes one type of negative electrode active material among these negative electrode active materials, or includes a mixture of multiple different negative electrode active materials. For example, the negative electrode active material layer (220) may include only amorphous carbon, or may include one or more 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).

[0052] In one embodiment, the negative electrode active material layer (220) may include a mixture of amorphous carbon and one or more 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 mixing ratio of the mixture of amorphous carbon and gold (Au), etc., may be, for example, 10:1 to 1:2, 5:1 to 1:1, or 4:1 to 2:1 by weight, but is not necessarily limited to this range and may be selected according to the characteristics of the required all-solid-state battery. When the negative electrode active material has this composition, the cycle characteristics of the all-solid-state battery can be further improved.

[0053] The binder included in the negative electrode active material layer (220) may be, for example, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, vinylidene fluoride / hexafluoropropylene copolymer, polyacrylonitrile, polymethyl methacrylate, etc., but is not necessarily limited thereto. The binder may include a single binder or a plurality of different binders.

[0054] Since the negative electrode active material layer (220) includes a binder, the negative electrode active material layer (220) can be stably formed on the negative electrode current collector (210). That is, the bonding strength between the negative electrode active material layer (220) and the negative electrode current collector (210) can be increased. In addition, cracking of the negative electrode active material layer (220) is suppressed despite changes in the volume and / or relative positions of the negative electrode active material layer (220) during the charge and discharge process. If the negative electrode active material layer (220) does not include a binder, the negative electrode active material layer (220) can be easily separated from the negative electrode current collector (210). As the negative electrode active material layer (220) is detached from the negative electrode current collector (210), the negative electrode current collector (210) can come into contact with the solid electrolyte layer at the exposed portion, thereby increasing the possibility of a short circuit occurring.

[0055] The negative electrode active material layer (220) is manufactured, for example, by providing a mixture in which the materials constituting the negative electrode active material layer (220) are dispersed onto the negative electrode current collector (210). Since a binder is included in the materials constituting the negative electrode active material layer (220), stable dispersion of the negative electrode active material in the mixture is possible. For example, when applying the mixture onto the negative electrode current collector (210) by screen printing, it is possible to suppress clogging of the screen (e.g., clogging by aggregates of the negative electrode active material) by the binder.

[0056] The negative electrode active material layer (220) may further include other additives in addition to the negative electrode active material and binder. The negative electrode active material layer (220) may further include, for example, fillers, coating agents, dispersants, ion conductive additives, etc.

[0057] The negative electrode active material layer (220) may have a smaller thickness than the positive electrode active material layer (120). The thickness of the negative electrode active material layer (220) may be, for example, 50% or less, 40% or less, 30% or less, 20% or less, 10% or less, or 5% or less of the thickness of the positive electrode active material layer (120). The thickness of the negative electrode active material layer (220) may be, for example, 1 um to 20 um, 2 um to 10 um, or 3 um to 7 um. If the thickness of the negative electrode active material layer (220) is too thin, lithium dendrites formed between the negative electrode active material layer (220) and the negative electrode current collector (210) may collapse the negative electrode active material layer (220), thereby deteriorating the cycle characteristics of the all-solid-state battery. If the thickness of the negative electrode active material layer (220) increases excessively, the energy density of the all-solid-state battery may decrease and the internal resistance of the all-solid-state battery due to the negative electrode active material layer (220) may increase, thereby deteriorating the cycle characteristics of the all-solid-state battery.

[0058] If the thickness of the negative electrode active material layer (220) decreases, the charge capacity of the negative electrode active material layer (220) may also decrease, for example. The charge capacity of the negative electrode active material layer (220) is, for example, 50% or less, 40% or less, 30% or less, 20% or less, 10% or less, 5% or less, or 2% or less than the charge capacity of the positive electrode active material layer (120). The charge capacity of the negative electrode active material layer (220) is, for example, 0.1% to 50%, 0.1% to 40%, 0.1% to 30%, 0.1% to 20%, 0.1% to 10%, 0.1% to 5%, or 0.1% to 2% than the charge capacity of the positive electrode active material layer (120). If the charge capacity of the negative electrode active material layer (220) is excessively small, the thickness of the negative electrode active material layer (220) becomes very thin, and the same defects as the defects described above that occur when the thickness of the negative electrode active material layer (220) becomes excessively thin may occur. If the charge capacity of the negative electrode active material layer (220) increases excessively, the same defects as the defects described above that occur when the thickness of the negative electrode active material layer (220) increases excessively may occur.

[0059] The charge capacity of the positive electrode active material layer (120) can be obtained by multiplying the charge capacity density (mAh / g) of the positive electrode active material by the mass of the positive electrode active material of the positive electrode active material layer (120). When the positive electrode active material layer (120) includes several types of positive electrode active materials, the [charge capacity density Х mass] value is calculated for each positive electrode active material, and the sum of these values ​​of the positive electrode active materials is the charge capacity of the positive electrode active material layer (120). The charge capacity of the negative electrode active material layer (220) can also be calculated in the same way. That is, the charge capacity of the negative electrode active material layer (220) is obtained by multiplying the charge capacity density (mAh / g) of the negative electrode active material by the mass of the negative electrode active material in the negative electrode active material layer (220). When the negative electrode active material layer (220) includes several types of negative electrode active materials, the [charge capacity density Х mass] value is calculated for each negative electrode active material, and the sum of these values ​​of the negative electrode active materials is the capacity of the negative electrode active material layer (220). Here, the charge capacity density of the positive electrode active material and the negative electrode active material may be an estimated capacity using an all-solid-state half-cell using lithium metal as a counter electrode. The charge capacity of the positive electrode active material layer (120) and the negative electrode active material layer (220) can be directly measured by measuring the charge capacity using the all-solid-state half-cell. The charge capacity density can be obtained by dividing the measured charge capacity by the mass of each active material. Meanwhile, in the present specification, the “charge capacity” of the positive electrode active material layer (120) and the negative electrode active material layer (220) means the initial charge capacity measured at the time of the first cycle charge.

[0060] Meanwhile, although not shown, a carbon layer may be further included to improve adhesion between the negative electrode active material layer (220) and the solid electrolyte layer (300).

[0061] The solid electrolyte layer (300) is disposed between the positive electrode layer (100) and the negative electrode layer (200) and includes a sulfide-based solid electrolyte having excellent lithium ion conductivity characteristics. The solid electrolyte included in the solid electrolyte layer (300) may be the same as or different from any one of the materials that may be included in the solid electrolyte included in the positive electrode active material layer (120) described above.

[0062] The solid electrolyte layer (300) of one embodiment may include a sulfide-based solid electrolyte. The sulfide-based solid electrolyte may be manufactured by treating starting materials such as Li2S and P2S5 by a melting rapid cooling method or a mechanical milling method. In addition, a heat treatment may be performed after the treatment. The solid electrolyte may be amorphous, crystalline, or a mixture thereof. In addition, the solid electrolyte may include, for example, at least sulfur (S), phosphorus (P), and lithium (Li) as constituent elements among the above-described sulfide-based solid electrolyte materials. For example, the solid electrolyte may be a material including Li2S-P2S5. When using a sulfide-based solid electrolyte material including Li2S-P2S5 to form the solid electrolyte, the mixing molar ratio of Li2S and P2S5 is, for example, in the range of Li2S:P2S5=50:50 to 90:10.

[0063] Sulfide-based solid electrolytes include, for example, Li 7-x PS 6-x Cl x (0≤x≤2), Li 7-x PS 6-x Br x (0≤x≤2), and Li 7-x PS 6-x I xIt may be an argyrodite-type compound including at least one selected from (0≤x≤2). In particular, the sulfide-based solid electrolyte may be an argyrodite-type compound including at least one selected from Li6PS5Cl, Li6PS5Br, and Li6PS5I.

[0064] Alternatively, the sulfide-based solid electrolyte is Li 7-a M a PS 6-c X c It may be an argyrodite-type compound containing (0≤a≤2, (0≤c≤2)), where X may be F, Br, Cl, or a combination thereof. M is candium (Sc), yttrium (Y), titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), technetium (Tc), rhenium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), zinc (Zn), cadmium (Cd), mercury (Hg), aluminum (Al), gallium (Ga), indium (In), thallium (Tl), silicon (Si), germanium (Ge), tin (Sn), lead (Pb), arsenic (As), antimony (Sb), bismuth (Bi), or a combination thereof. Can be.

[0065] The density of the argyrodite-type solid electrolyte may be 1.5 g / cc to 2.0 g / cc. When the argyrodite-type solid electrolyte has a density of 1.5 g / cc or more, the internal resistance of the all-solid-state battery is reduced, and the defect of the solid electrolyte membrane being penetrated and short-circuited due to the formation of lithium dendrites can be prevented. The elastic modulus of the solid electrolyte is, for example, 15 GPa to 35 GPa.

[0066] The solid electrolyte layer (300) may further include a binder. The binder included in the solid electrolyte layer (300) may be, for example, styrene butadiene rubber (SBR), polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, etc., but is not limited thereto. The binder of the solid electrolyte layer (300) may be the same as or different from the binder included in the positive electrode active material layer (120) or the binder included in the negative electrode active material layer (220).

[0067] For example, the solid electrolyte layer (300) may include a first solid electrolyte layer (300a) and a second solid electrolyte layer (300b). The first solid electrolyte layer (300a) may be adjacent to the positive electrode layer (100), and the second solid electrolyte layer (300b) may be adjacent to the negative electrode layer (200).

[0068] The first solid electrolyte layer (300a) and the second solid electrolyte layer (300b) may have the same or different thicknesses. The first solid electrolyte layer (300a) may have a first thickness (TK1), and the second solid electrolyte layer (300b) may have a second thickness (TK2). For example, the first thickness (TK1) may be greater than the second thickness (TK2). For example, the first thickness (TK1) may be 2 to 100 times greater than the second thickness (TK2). For example, the second thickness (TK2) may be greater than the first thickness (TK1). For example, the second thickness (TK2) may be 2 to 100 times greater than the first thickness (TK2).

[0069] For example, the area of ​​the anode layer (100) and the area of ​​the cathode layer (200) may be different from each other. Specifically, the area of ​​the cathode layer (200) may be larger than the area of ​​the anode layer (100). The anode layer (100) may be completely overlapped within the cathode layer (200).

[0070] In one embodiment of the present invention, the first solid electrolyte layer (300a) may have substantially the same area as the positive electrode layer (100). The second solid electrolyte layer (300b) may have substantially the same area as the negative electrode layer (200). 'Substantially the same area' may be defined as an area in which the difference between two different areas is within 10%.

[0071] Specifically, the anode layer (100) and the first solid electrolyte layer (300a) may have an anode width (Wc) in the first direction (D1). The cathode layer (200) and the second solid electrolyte layer (300b) may have a cathode width (Wa) in the first direction (D1). The anode width (Wc) may be smaller than the cathode width (Wa).

[0072] The all-solid-state battery according to the present embodiment can be manufactured by forming a positive electrode laminate of a positive electrode layer (100) and a first solid electrolyte layer (300a), forming a negative electrode laminate of a negative electrode layer (200) and a second solid electrolyte layer (300b), and then laminating the positive electrode laminate and the negative electrode laminate.

[0073] Referring to FIG. 2, the all-solid-state battery may include a gasket (GSK). The gasket (GSK) may fill in the step difference in the side surface of the all-solid-state battery caused by the difference in the area of ​​the negative electrode laminate and the positive electrode laminate. The gasket (GSK) may surround the side surfaces of the positive electrode laminate of the all-solid-state battery along the first and second directions (D1, D2). For example, the widths of the gasket (GSK) in the first and third directions (D1, D3) respectively may be substantially the same as the widths of the positive electrode laminate in the first and third directions (D1, D3) respectively. Accordingly, even when negative electrode laminates and positive electrode laminates having different areas are laminated and pressed, damage due to the step difference in the side surface of the all-solid-state battery can be prevented. The term “substantially the same width” may be defined as a width that can prevent damage due to the step difference in the side surface of the all-solid-state battery even when negative electrode laminates and positive electrode laminates having different areas are laminated and pressed.

[0074]

[0075] Method for manufacturing an all-solid-state battery

[0076] FIG. 3 is a flowchart illustrating a method for manufacturing an all-solid-state battery according to embodiments of the present invention. FIGS. 4 to 9 are each cross-sectional views illustrating a method for manufacturing an all-solid-state battery according to FIG. 3.

[0077] Referring to FIG. 3, a method for manufacturing an all-solid-state battery according to embodiments of the present invention may include preparing a negative electrode layer (S100); preparing a positive electrode layer (S200); preparing a solid electrolyte membrane (S300); forming a folding portion in the solid electrolyte membrane (S500); providing a positive electrode layer and a negative electrode layer to the folding portion (S700); and bringing the positive electrode layer, the negative electrode layer, and the solid electrolyte membrane into contact with each other (S900). Hereinafter, for convenience of explanation, descriptions of the same matters as those described with reference to FIGS. 1 and 2 will be omitted, and differences will be described in detail.

[0078]

[0079] Referring to FIG. 4, a negative electrode layer can be prepared (S100). The negative electrode layer can include a first negative electrode layer (200) and a second negative electrode layer (202). The first negative electrode layer (200) can include a pair of negative electrode active material layers (220) and a negative electrode current collector (210) between the pair of negative electrode active material layers (220). The second negative electrode layer (202) can include a negative electrode current collector (210) and a negative electrode active material layer (220).

[0080] For example, preparing a negative electrode layer (S100) may include preparing a negative electrode active material composition by mixing the above-described negative electrode active material and binder in the above-described ratio, and applying and drying the above-described negative electrode active material composition on a negative electrode current collector (210).

[0081]

[0082] Referring to FIG. 5, a positive electrode layer can be prepared (S200). The positive electrode layer can include a first positive electrode layer (100) and a second positive electrode layer (102). The first positive electrode layer (100) can include a pair of positive electrode active material layers (120) and a positive electrode current collector (110) between the pair of positive electrode active material layers (120). The second positive electrode layer (102) can include a positive electrode current collector (110) and a positive electrode active material layer (120).

[0083] For example, preparing a positive electrode layer (S200) may include preparing a positive electrode active material composition by mixing the above-described positive electrode active material, solid electrolyte, conductive material, and binder in the above-described ratio, and applying and drying the positive electrode active material composition on a positive electrode current collector (110).

[0084]

[0085] Referring to Fig. 6, a solid electrolyte membrane (SEM) can be prepared (S300). The solid electrolyte membrane (SEM) can be a free-standing membrane. A free-standing membrane can be defined as a thin film or film that maintains a certain shape on its own without being supported by another substrate. Accordingly, the solid electrolyte layer described above can be prepared as a separate free-standing membrane and then placed between the positive electrode layer and the negative electrode layer.

[0086] A solid electrolyte membrane (SEM) may include a first portion (P1), a second portion (P2), and a third portion (P3). The first portion (P1), the second portion (P2), and the third portion (P3) may be positioned horizontally side by side. The first portion (P1), the second portion (P2), and the third portion (P3) will be described in detail with reference to FIGS. 7 to 9.

[0087] For example, preparing a solid electrolyte membrane (SEM) (S300) may include coating a solid electrolyte slurry on a porous polymer matrix and curing the solid electrolyte slurry. As a result, the solid electrolyte membrane (SEM) may include a porous polymer matrix and a sulfide-based solid electrolyte having the above-described argyrodite crystal structure.

[0088] The solid electrolyte slurry may be coated on at least a portion of the porous polymer matrix. For example, both sides of the porous polymer matrix may be fixed using a binder, and the solid electrolyte slurry may be coated on the remaining area excluding both sides. For example, the binder may include at least one of a thermosetting resin or an ultraviolet-curable resin. For example, the porous polymer matrix may be provided on a release film, and the release film may be subsequently peeled off.

[0089] The solid electrolyte slurry may include a sulfide-based solid electrolyte having the above-described argyrodite crystal structure and a binder. The above-described solid electrolyte can penetrate into the pores of the porous polymer matrix. For example, the average particle diameter (D50) of the solid electrolyte may be 500 nm to 7 μm, or 1 μm to 3 μm.

[0090] The porous polymer matrix may include a plurality of pores. For example, the porous polymer matrix may have a porosity of 60% or more, for example, a porosity of 60% to 100%, or a porosity of 70% to 80%. For example, the pore size of the porous polymer matrix may be 50 nm to 500 μm. When the porosity and pore size satisfy the numerical ranges described above, the solid electrolyte slurry can penetrate into the porous polymer matrix, and the porous polymer matrix can retain a sufficient amount of solid electrolyte therein to function as an electrolyte membrane.

[0091] The porous polymer matrix may have a thin thickness. The porous polymer matrix (PW) may have a thickness of 5 μm to 20 μm. For example, the porous polymer matrix (PW) may have a thickness of 10 μm to 15 μm.

[0092] The weight of the porous polymer matrix (PW) is 2 g / m 2 4g / m 2 may be. For example, the weight of the porous polymer matrix (PW) is 2.5 g / m 2 3.5g / m 2 It could be.

[0093] The tensile strength of the porous polymer matrix (PW) may be 0.1 N / mm to 0.2 N / mm. For example, the tensile strength of the porous polymer matrix (PW) may be 0.1 N / mm to 0.13 N / mm.

[0094] The air permeability per thickness of the porous polymer matrix (PW) may be from 0.1 sec / 100 ml to 1 sec / 100 ml. For example, the air permeability per thickness of the porous polymer matrix (PW) may be from 0.1 sec / 100 ml to 0.5 sec / 100 ml.

[0095] The porous polymer matrix (PW) may include at least one selected from the group consisting of polyester, polyolefin, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyethersulfone, polyphenylene oxide, and polyphenylene sulfide. For example, the polyester may include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and the like.

[0096] In one embodiment, the porous polymer matrix may be a porous nonwoven fabric.

[0097] The solid electrolyte slurry may be curable. For example, curing the solid electrolyte slurry may include at least one of thermal curing and ultraviolet curing. For example, thermal curing may be performed at a temperature of 90°C to 130°C for 1 to 10 minutes. For example, ultraviolet curing may be performed with ultraviolet (UV) light having a wavelength of 200 nm to 365 nm.

[0098]

[0099] Referring to Fig. 7, a folding portion can be formed on a solid electrolyte membrane (SEM) (S500). The folding portion can include a first folding portion (FP1) and a second folding portion (FP2). The first folding portion (FP1) can be formed between the first portion (P1) and the second portion (P2). The second folding portion (FP2) can be formed between the second portion (P2) and the third portion (P3).

[0100] The first folding portion (FP1) and the second folding portion (FP2) may be formed by alternately folding the solid electrolyte membrane (SEM). For example, after forming the folding portions (FP1, FP2), the solid electrolyte membrane (SEM) may be folded. The folded solid electrolyte membrane (SEM) may be unfolded again so that the folding portions have a specific angle, and a positive electrode layer and a negative electrode layer may be provided on each of the folding portions. In another example, the folding portions (FP1, FP2) may be formed at a specific angle, and a positive electrode layer and a negative electrode layer may be provided.

[0101] The angles of the first folding portion (FP1) and the second folding portion (FP2) are not limited, but may be an angle sufficient to provide and adjacent the positive electrode layer and the negative electrode layer, as will be described later. For example, the first folding portion (FP1) and the second folding portion (FP2) may have an acute angle. The first folding portion (FP1) may have a first angle (A1) from the second portion (P2). The second folding portion (FP2) may have a second angle (A2) from the second portion (P2). For example, the first angle (A1) may be 10° to 80°. For example, the second angle (A2) may be -10° to -80°.

[0102]

[0103] Referring to Fig. 8, a positive electrode layer and a negative electrode layer may be provided on each of the folding sections (S700). The positive electrode layer and the negative electrode layer may be provided alternately with a solid electrolyte membrane (SEM) interposed therebetween. That is, they may be provided in the following order: a second negative electrode layer (202), a first positive electrode layer (100), a first negative electrode layer (200), and a second positive electrode layer (102) along the third direction (D3).

[0104] A third portion (P3) of the solid electrolyte membrane (SEM) may be interposed between the second cathode layer (202) and the first anode layer (100). A second portion (P2) of the solid electrolyte membrane (SEM) may be interposed between the first anode layer (100) and the first cathode layer (200). A first portion (P1) of the solid electrolyte membrane (SEM) may be interposed between the first cathode layer (200) and the second anode layer (102).

[0105] Each of the first portion (P1), the second portion (P2), and the third portion (P3) is sufficiently long to accommodate the anode layer and the cathode layer. That is, the length of each of the first portion (P1), the second portion (P2), and the third portion (P3) is substantially equal to or greater than the anode width (Wc) and the cathode width (Wa), respectively.

[0106] The first cathode layer (200) is provided between the first portion (P1) and the second portion (P2), and may be adjacent to the first folding portion (FP1). In this step, the first cathode layer (200) may be in contact with the first folding portion (FP1).

[0107] The first anode layer (100) is provided between the second portion (P2) and the third portion (P3), and may be adjacent to the second folding portion (FP2). In this step, the first anode layer (100) may be in contact with the second folding portion (FP2).

[0108] The second cathode layer (202) may be provided on the third portion (P3) and may be adjacent to the third portion (P3). In this step, the second cathode layer (202) may be in contact with the third portion (P3). The order in which the second cathode layer (202) is provided is not limited. For example, the second cathode layer (202) may be provided together with the first cathode layer (200). In another example, the second cathode layer (202) may be provided after the first cathode layer (200) is provided.

[0109] The second anode layer (102) may be provided on the first portion (P1) and may be adjacent to the first portion (P1). In this step, the second anode layer (102) may be in contact with the first portion (P1). The order in which the second anode layer (102) is provided is not limited. For example, the second anode layer (102) may be provided together with the first anode layer (100). In another example, the first anode layer (100) may be provided and then the second anode layer (102) may be provided.

[0110]

[0111] Referring to FIG. 9, the anode layer, the cathode layer, and the solid electrolyte membrane may be in contact with each other (S900). For example, this step may include pressurizing the anode layers (100, 102), the cathode layers (200, 202), and the solid electrolyte membrane (SEM) with a first pressure. For example, before pressurizing, the anode layers (100, 102) and the cathode layers (200, 202) may be provided and aligned such that the centers of the anode layers and the cathode layers are aligned respectively.

[0112] This step may include a pressurizing process using a hydraulic plate press. However, this method is not necessarily limited to this method, and any pressurizing process applicable in the relevant technical field may be applied. For example, pressurizing processes such as roll press and isostatic press may be applied.

[0113] The first pressure may be defined as a pressure applied from the outside of the anode layer, the cathode layer, and the solid electrolyte membrane toward the inside of the anode layer, the cathode layer, and the solid electrolyte membrane. For example, the first pressure may include a pressure applied from the upper surface, lower surface, and side surface of the anode layer, the cathode layer, and the solid electrolyte membrane toward the inside of the anode layer, the cathode layer, and the solid electrolyte membrane. In this case, the first pressure may be a pressure that not only allows the solid electrolyte layer (300) and the anode layers and the cathode layers to come into contact with each other, but also allows the first vertical portion (VP1) and the second vertical portion (VP2) to be formed on the side surface of the anode layer and the cathode layer.

[0114] As another example, the first pressure may include a pressure applied from the upper and lower surfaces of the anode layer, the cathode layer, and the solid electrolyte membrane toward the interior of the anode layer, the cathode layer, and the solid electrolyte membrane. The pressure applied from the side of the anode layer, the cathode layer, and the solid electrolyte membrane toward the interior of the anode layer, the cathode layer, and the solid electrolyte membrane may be less than the first pressure. In this case, the first pressure may be a pressure at which the solid electrolyte layer (300) and the anode layers and the cathode layers can come into contact with each other.

[0115] The first pressure may be 2 MPa or more. Specifically, the first pressure may be 2.5 MPa or more, 3 MPa or more, or 3.5 MPa or more. The first pressure may be 100 MPa or less. Specifically, the first pressure may be 20 MPa or less, 10 MPa or less, 5 MPa or less, or 4 MPa or less.

[0116] Thereby, the anode layers (100, 102), the cathode layers (200, 202) and the solid electrolyte membrane (SEM) can be in contact with each other, and as will be described later, the solid electrolyte layer (300) can be formed between the anode layers (100, 102) and the cathode layers (200, 202). In addition, through pressurization, the solid electrolyte layer (300) can include a first horizontal portion, a first vertical portion, a second horizontal portion, a second vertical portion and a third horizontal portion (see FIG. 10). That is, by pressurizing the upper, lower and side surfaces of the anode layer, the cathode layer and the solid electrolyte membrane with the first pressure, not only are the first horizontal portion, the second horizontal portion and the third horizontal portion interposed between the anode layer and the cathode layer formed, but also the first vertical portion and the second vertical portion covering the side surfaces of the anode layer and the cathode layer and vertically connecting the horizontal portions to each other can be formed.

[0117]

[0118] Using a manufacturing method according to one embodiment of the present invention, an all-solid-state battery can be easily manufactured and continuously produced. Furthermore, using a solid electrolyte membrane (SEM) comprising a porous polymer matrix and a sulfide-based solid electrolyte according to one embodiment of the present invention, a conventional elastic pad can be omitted, and an all-solid-state battery with high capacity and / or energy density can be manufactured.

[0119]

[0120] All-solid-state batteries

[0121] FIGS. 10, 11a, 11b, and 12 are cross-sectional views illustrating all-solid-state batteries according to embodiments of the present invention. For convenience of explanation, the same details as those described with reference to FIGS. 1 to 9 will be omitted below, and differences will be described in detail.

[0122] Referring to FIG. 10, an all-solid-state battery according to one embodiment of the present invention may include a second cathode layer (202), a first cathode layer (100), a first cathode layer (200), a second cathode layer (102), and a solid electrolyte layer (300).

[0123] The first negative electrode layer (200) may include a pair of negative electrode active material layers (220) and a negative electrode current collector (210) between the pair of negative electrode active material layers. The second negative electrode layer (202) may include a negative electrode active material layer (220) and a negative electrode current collector (210).

[0124] The first positive electrode layer (100) may include a pair of positive electrode active material layers (120) and a positive electrode current collector (110) between the pair of positive electrode active material layers. The second positive electrode layer (102) may include a positive electrode active material layer (120) and a positive electrode current collector (110).

[0125] The solid electrolyte layer (300) may include, for example, a sulfide-based solid electrolyte having a porous polymer matrix and an argyrodite crystal structure.

[0126] The solid electrolyte layer (300) may include a first horizontal portion (HP1), a first vertical portion (VP1), a second horizontal portion (HP2), a second vertical portion (VP2), and a third horizontal portion (HP3). The first vertical portion (VP1) may connect the first horizontal portion (HP1) and the second horizontal portion (HP2) to each other. The second vertical portion (VP2) may connect the second horizontal portion (HP2) and the third horizontal portion (HP3) to each other.

[0127] In one embodiment, the first vertical portion (VP1) and the vertical portion (VP2) may correspond to the first folding portion (FP1) and the second folding portion (FP2) described above with reference to FIGS. 7 to 9, respectively. The first horizontal portion (HP1), the second horizontal portion (HP2), and the third horizontal portion (HP3) may correspond to the first portion (P1), the second portion (P2), and the third portion (P3) described above with reference to FIGS. 7 to 9, respectively.

[0128] The first cathode layer (200) may be disposed on the first anode layer (100). The first cathode layer (200) may be interposed between the first horizontal portion (HP1) and the second horizontal portion (HP2). The first cathode layer (200) may be in contact with the first horizontal portion (HP1), the first vertical portion (VP1), and the second horizontal portion (HP2). One of the pair of cathode active material layers (220) of the first cathode layer (200) may be in contact with the lower surface of the first horizontal portion (HP1). The other of the pair of cathode active material layers (220) of the first cathode layer (200) may be in contact with the upper surface of the second horizontal portion (HP2).

[0129] The first cathode layer (200) may include a first side surface (SD1) and a second side surface (SD2). The first side surface (SD1) and the second side surface (SD2) may face each other in the first direction (D1). The second side surface (SD2) may be exposed from the solid electrolyte layer (300).

[0130] The first positive electrode layer (100) may be interposed between the second horizontal portion (HP2) and the third horizontal portion (HP3). The first positive electrode layer (100) may be in contact with the second horizontal portion (HP2), the second vertical portion (VP2), and the third horizontal portion (HP3). One of the pair of positive electrode active material layers (120) of the first positive electrode layer (100) may be in contact with the lower surface of the second horizontal portion (HP2). The other of the pair of positive electrode active material layers (120) of the first positive electrode layer (100) may be in contact with the upper surface of the third horizontal portion (HP3).

[0131] The first anode layer (100) may include a third side surface (SD3) and a fourth side surface (SD4). The third side surface (SD3) and the fourth side surface (SD4) may face each other in the first direction (D1). The third side surface (SD3) may be exposed from the solid electrolyte layer (300).

[0132] The second positive electrode layer (102) may be placed on the first horizontal portion (HP1). The positive electrode active material layer (120) of the second positive electrode layer (102) may be in contact with the upper surface of the first horizontal portion (HP1).

[0133] The second cathode layer (202) may be placed below the third horizontal portion (HP3). The cathode active material layer (220) of the second cathode layer (202) may be in contact with the lower surface of the third horizontal portion (HP3).

[0134] The solid electrolyte layer (300) may be disposed between the anode layers (100, 102) and the cathode layers (200, 202). That is, a first horizontal portion (HP1) may be disposed between the first cathode layer (200) and the second anode layer (102). A second horizontal portion (HP2) may be disposed between the first cathode layer (200) and the first anode layer (100). A third horizontal portion (HP3) may be disposed between the first anode layer (100) and the second cathode layer (202).

[0135] For example, when manufacturing an all-solid-state battery, a first pressure may be applied toward the inside of the positive electrode layer, the negative electrode layer, and the solid electrolyte membrane from the upper, lower, and side surfaces of the positive electrode layer, the negative electrode layer, and the solid electrolyte membrane. The first pressure may be a pressure that allows the solid electrolyte layer (300) and the positive electrode layers and the negative electrode layers to come into contact with each other. In addition, the first pressure may be a pressure that allows the formation of a first vertical portion (VP1) and a second vertical portion (VP2) on the side surfaces of the positive electrode layer and the negative electrode layer.

[0136] Accordingly, the all-solid-state battery may include the following solid electrolyte layer (300). The first vertical portion (VP1) may vertically connect the first horizontal portion (HP1) and the second horizontal portion (HP2) to each other. That is, the first vertical portion (VP1) may be parallel to the third direction (D3). The second vertical portion (VP2) may vertically connect the second horizontal portion (HP2) and the third horizontal portion (HP3) to each other. That is, the second vertical portion (VP2) may be parallel to the third direction (D3). The first side surface (SD1) may be covered by the first vertical portion (VP1), the second side surface (SD2) may be exposed from the solid electrolyte layer (300), the third side surface (SD3) may be exposed from the solid electrolyte layer (300), and the fourth side surface (SD4) may be covered by the second vertical portion (VP2).

[0137] As another example, when manufacturing an all-solid-state battery, the first pressure may be applied from the upper and lower surfaces of the positive electrode layer, the negative electrode layer, and the solid electrolyte membrane toward the inside of the positive electrode layer, the negative electrode layer, and the solid electrolyte membrane. Alternatively, when manufacturing an all-solid-state battery, the first pressure applied from the upper and lower surfaces of the positive electrode layer, the negative electrode layer, and the solid electrolyte membrane toward the inside of the positive electrode layer, the negative electrode layer, and the solid electrolyte membrane may be greater than the pressure applied from the side surfaces of the positive electrode layer, the negative electrode layer, and the solid electrolyte membrane toward the inside of the positive electrode layer, the negative electrode layer, and the solid electrolyte membrane.

[0138] Accordingly, the all-solid-state battery may include the following solid electrolyte layer (300). The first vertical portion (VP1) may connect the first horizontal portion (HP1) and the second horizontal portion (HP2) to each other in a curved manner. That is, the first vertical portion (VP1) may have a curved shape. The second vertical portion (VP2) may connect the second horizontal portion (HP2) and the third horizontal portion (HP3) to each other in a curved manner. That is, the second vertical portion (VP2) may have a curved shape. The second side surface (SD2) may be exposed from the solid electrolyte layer (300), and the third side surface (SD3) may be exposed from the solid electrolyte layer (300). The first side surface (SD1) and the fourth side surface (SD4) may include portions exposed from the solid electrolyte layer (300).

[0139]

[0140] Referring to FIG. 11a, an all-solid-state battery according to one embodiment of the present invention may include a composite substrate (CPS). For example, at least one of the positive electrode collectors (110) and the negative electrode collectors (210) may be replaced with a composite substrate (CPS).

[0141] Referring to FIG. 11b, the composite substrate (CPS) may include a support layer (SPL) and a first metal layer (MEL1) and a second metal layer (MEL2) provided on both sides of the support layer, respectively. Each of the first and second metal layers (MEL1, MEL2) of the composite substrate (CPS) may be in contact with the positive electrode active material layer (120) of the positive electrode layer (100, 102) or the negative electrode active material layer (220) of the negative electrode layer (200, 202). Each of the first and second metal layers (MEL1, MEL2) of the composite substrate (CPS) may correspond to the current collector (110 or 210) described above with reference to FIG. 10.

[0142] The support layer (SPL) may include a polymer film. For example, the support layer (SPL) may include a polyethylene film, a polypropylene film, a polyvinylidene chloride film, or a multilayer film comprising a combination thereof. The support layer (SPL) may have excellent ion permeability and excellent mechanical strength.

[0143] Each of the first and second metal layers (MEL1, MEL2) may include at least one of aluminum, an aluminum alloy, copper, a copper alloy, nickel, a nickel alloy, titanium, a titanium alloy, iron, an iron alloy, silver, and a silver alloy.

[0144] In one embodiment of the present invention, each of the first and second metal layers (MEL1, MEL2) may have a thickness of 200 nm to 5 μm. The support layer (SPL) may have a thickness of 3 μm to 10 μm. The thickness of the support layer (SPL) may be greater than the thickness of each of the first and second metal layers (MEL1, MEL2).

[0145]

[0146] Referring to FIG. 12, an all-solid-state battery according to one embodiment of the present invention may further include a gasket (GSK) surrounding a side surface of the first positive electrode layer (100). For example, the gasket (GSK) may include a gasket surrounding a third side surface (SD3) and a fourth side surface (SD4) of the first positive electrode layer (100). Accordingly, the gasket (GSK) may be interposed between the first horizontal portion (HP1) and the second horizontal portion (HP2) together with the first positive electrode layer (100).

[0147] The cross-section of the gasket (GSK) may include a first side portion (GP1) and a second side portion (GP2). The first side portion (GP1) may be disposed on the third side portion (SD3). The second side portion (GP2) may be disposed on the fourth side portion (SD4).

[0148] The second side portion (GP2) may be interposed between the fourth side portion (SD4) and the second vertical portion (VP2). Meanwhile, the first side portion (GP1) may be exposed from the solid electrolyte layer (300). That is, unlike the second side portion (GP2), one side of the first side portion (GP1) may be adjacent to the third side portion (SD3), but the other side opposite to the one side may not be adjacent to the solid electrolyte layer (300).

[0149] The all-solid-state battery may further include a gasket surrounding the side surface of the second positive electrode layer (102). For example, the gasket (GSK) may include a gasket surrounding the first side surface (SD1) and the second side surface (SD2) of the second positive electrode layer (102). Thus, the gasket may be disposed on the first horizontal portion (HP1) together with the second positive electrode layer (102).

[0150] The total width of the anode layer (100, 102) and the gasket (GSK) may be substantially the same as the cathode layer (200, 202). For example, the total width of the first anode layer (100), the first side (GP1), and the second side (GP2) may be substantially the same as the first cathode layer (200). The total width of the first anode layer (100), the first side (GP1), and the second side (GP2) may be the first anode width (Wc1), the width of the first side (W GP1 ) and the width of the second side (W GP2 ) can be defined as the sum of the widths. Accordingly, even when positive electrode layers (100, 102) and negative electrode layers (200, 202) having different areas are laminated and pressed, damage due to steps on the side of the all-solid-state battery can be prevented. 'Substantially the same width' can be defined as a width that can prevent damage due to steps on the side of the all-solid-state battery even when negative electrode laminates and positive electrode laminates having different areas are laminated and pressed.

[0151]

[0152] While embodiments of the present invention have been described with reference to the attached drawings, the present invention may be implemented in other specific forms without altering the technical spirit or essential features thereof. Therefore, it should be understood that the embodiments described above are exemplary in all respects and are not limiting.

Claims

1. Preparing a first negative electrode layer including a pair of negative electrode active material layers and a negative electrode current collector between the pair of negative electrode active material layers; Preparing a first cathode layer including a pair of cathode active material layers and a cathode current collector between the pair of cathode active material layers; Preparing a solid electrolyte membrane comprising a first part, a second part, and a third part positioned horizontally side by side; Forming a first folding portion between the first part and the second part, and a second folding portion between the second part and the third part; Providing the first cathode layer between the first part and the second part, so that the first cathode layer is adjacent to the first folding portion; Providing the first anode layer between the second part and the third part, so that the first anode layer is adjacent to the second folding part; and Including bringing the first anode layer, the first cathode layer and the solid electrolyte membrane into contact with each other; Method for manufacturing an all-solid-state battery.

2. In paragraph 1, The first folding portion has a first angle from the second portion, The first angle is 10° to 80°, Method for manufacturing an all-solid-state battery.

3. In paragraph 1, The second folding portion has a second angle from the second portion, The second angle is between -10° and -80°, Method for manufacturing an all-solid-state battery.

4. In paragraph 1, The second part is interposed between the first anode layer and the first cathode layer, Method for manufacturing an all-solid-state battery.

5. In paragraph 1, The first cathode layer is adjacent to the first folding portion, including the first cathode layer being in contact with the first folding portion. Method for manufacturing an all-solid-state battery.

6. In paragraph 1, The first anode layer is adjacent to the second folding portion, including the first anode layer being in contact with the second folding portion. Method for manufacturing an all-solid-state battery.

7. In paragraph 1, Further comprising providing a second cathode layer on the third portion, The second cathode layer includes a cathode current collector and a cathode active material layer. Method for manufacturing an all-solid-state battery.

8. In paragraph 1, Further comprising providing a second anode layer on the first portion, The second positive electrode layer includes a positive electrode current collector and a positive electrode active material layer. Method for manufacturing an all-solid-state battery.

9. In paragraph 1, Bringing the first anode layer, the first cathode layer, and the solid electrolyte membrane into contact with each other includes pressurizing the first anode layer, the first cathode layer, and the solid electrolyte membrane. Method for manufacturing an all-solid-state battery.

10. A first cathode layer comprising a pair of cathode active material layers and a cathode current collector between the pair of cathode active material layers; A first negative electrode layer disposed on the first positive electrode layer and including a pair of negative electrode active material layers and a negative electrode current collector between the pair of negative electrode active material layers; and A solid electrolyte layer including a first horizontal portion, a first vertical portion, a second horizontal portion, a second vertical portion, and a third horizontal portion; The first vertical portion connects the first horizontal portion and the second horizontal portion to each other, The second vertical portion connects the second horizontal portion and the third horizontal portion to each other, The first cathode layer is interposed between the first horizontal portion and the second horizontal portion, The first anode layer is interposed between the second horizontal portion and the third horizontal portion, The first cathode layer includes a first side and a second side facing each other in the first direction, The first anode layer includes a third side and a fourth side facing each other in the first direction, The second side is exposed from the solid electrolyte layer, The third side is exposed from the solid electrolyte layer, All-solid-state battery.

11. In paragraph 10, The first cathode layer is in contact with the first horizontal portion and the second horizontal portion, One of the pair of negative electrode active material layers of the first negative electrode layer is in contact with the lower surface of the first horizontal portion, The other of the pair of negative active material layers is in contact with the upper surface of the second horizontal portion, All-solid-state battery.

12. In paragraph 10, The first anode layer is in contact with the second horizontal portion and the third horizontal portion, One of the pair of positive electrode active material layers of the first positive electrode layer is in contact with the lower surface of the second horizontal portion, The other of the pair of positive electrode active material layers is in contact with the upper surface of the third horizontal portion, All-solid-state battery.

13. In paragraph 10, Further comprising a second positive electrode layer disposed on the first horizontal portion and including a positive electrode current collector and a positive electrode active material layer, The positive electrode active material layer of the second positive electrode layer is in contact with the upper surface of the first horizontal portion, All-solid-state battery.

14. In paragraph 10, Further comprising a second negative electrode layer disposed below the third horizontal portion and including a negative electrode current collector and a negative electrode active material layer, The negative electrode active material layer of the second negative electrode layer is in contact with the lower surface of the third horizontal portion, All-solid-state battery.

15. In paragraph 10, A second horizontal portion is disposed between the first cathode layer and the first anode layer, All-solid-state battery.

16. In paragraph 10, The above solid electrolyte layer includes a porous polymer matrix and a sulfide-based solid electrolyte having an argyrodite crystal structure. All-solid-state battery.

17. In paragraph 10, The first cathode layer has a first cathode width in the first direction, The first anode layer has a first anode width in the first direction, The first cathode width is greater than the first anode width, All-solid-state battery.

18. In paragraph 10, Further comprising a gasket surrounding the third side and the fourth side of the first anode layer, The gasket comprises a first side on the third side and a second side on the fourth side, The second side is interposed between the fourth side and the second vertical part. All-solid-state battery.

19. In paragraph 18, The above first side is exposed from the solid electrolyte layer, All-solid-state battery.

20. In paragraph 18, The total width of the first anode layer, the first side, and the second side is the same as that of the first cathode layer. All-solid-state battery.