Pouch film comprising functional layer, all-solid-state battery comprising same, and method for producing same

Abstract

The present invention relates to an all-solid-state battery. More specifically, the all-solid-state battery comprises a pouch for covering an electrode assembly, the pouch comprising adhesive parts in contact with lead tabs, and the adhesive parts comprising a metal layer, a polymer layer, and an insulation layer between the metal and polymer layers.

Description

Pouch film including a functional layer, all-solid-state battery including the same, and method for manufacturing the same

[0001] This relates to a pouch-type all-solid-state battery and a method for manufacturing the same.

[0002]

[0003] Recent industrial demands have led to the active development of batteries with high energy density and stability. 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.

[0004] 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.

[0005] Conventional pouch-type batteries are prone to thermal and mechanical damage. This can lead to short circuits, potentially resulting in fire or explosion.

[0006]

[0007] The problem to be solved by the present invention is to provide a pouch-type all-solid-state battery with improved stability.

[0008] Another problem to be solved by the present invention is to provide a method for manufacturing a pouch-type all-solid-state battery with improved stability.

[0009]

[0010] An all-solid-state battery according to the concept of the present invention may include an electrode assembly in which at least one unit cell is stacked; a lead tab electrically connected to the unit cell; and a pouch for packaging the electrode assembly.

[0011] The unit cell includes a first electrode, a second electrode having a different polarity from the first electrode, and a solid electrolyte between the first and second electrodes, and the all-solid-state battery further includes a first substrate tab extending in one direction from the first electrode, and a second substrate tab extending in an opposite direction to the one direction from the second electrode, wherein the lead tab includes a first lead tab connected to the first substrate tab and extending outward from the pouch along the one direction, and a second lead tab connected to the second substrate tab and extending outward from the pouch along the opposite direction, and the pouch includes a first joint portion in contact with the first lead tab, wherein the first joint portion includes a metal layer, a polymer layer in contact with the first lead tab, and an insulating layer between the metal layer and the polymer layer, and the insulating layer may include an oxide of a metal in the metal layer.

[0012] According to another concept of the present invention, an all-solid-state battery comprises: an electrode assembly in which at least one unit cell is stacked; a lead tab electrically connected to the unit cell; and a pouch for packaging the unit cell, wherein the unit cell includes a positive electrode, a negative electrode, and a solid electrolyte, and the lead tab includes a first lead tab electrically connected to the positive electrode and a second lead tab electrically connected to the negative electrode, and the pouch includes a polymer layer, an insulating layer, and a metal layer sequentially stacked, and the pouch includes a first joint portion in contact with the first lead tab and a second joint portion in contact with the second lead tab, and the insulating layer can be selectively provided to at least one of the first joint portion and the second joint portion.

[0013] A method for manufacturing an all-solid-state battery according to another concept of the present invention may include a step of manufacturing a pouch film; a step of manufacturing an electrode assembly; and a step of assembling a battery. The step of manufacturing the pouch film may include a step of preparing a metal layer; a step of forming an insulating layer by oxidizing the surface of the metal layer; and a step of forming a polymer layer on the insulating layer.

[0014]

[0015] According to one embodiment of the present invention, an insulating layer is formed on a pouch film for an all-solid-state battery, thereby providing a pouch-type all-solid-state battery with improved stability.

[0016] According to one embodiment of the present invention, a method for manufacturing an all-solid-state battery with improved mass productivity and processability can be provided.

[0017]

[0018] Figure 1 is a cross-sectional diagram schematically illustrating an all-solid-state battery.

[0019] Figure 2 is a plan view of an all-solid-state battery according to one embodiment.

[0020] Figure 3 is a cross-sectional view taken along line A-A' of Figure 2.

[0021] Figure 4 is a cross-sectional view of an all-solid-state battery unit cell according to one embodiment.

[0022] Figure 5 is a cross-sectional view of a pouch-type all-solid-state battery according to one embodiment.

[0023] Figure 6 is an enlarged view of area M of Figure 5.

[0024] Figure 7 is an enlarged view of the N area of ​​Figure 6.

[0025] Figure 8 is a cross-sectional view of a pouch-type all-solid-state battery according to one embodiment.

[0026] Figure 9a is an enlarged view of the X area of ​​Figure 8.

[0027] Figure 9b is an enlarged view of the Y region of Figure 8.

[0028] Fig. 10 is an enlarged view of a pouch film according to one embodiment.

[0029] Figure 11 is a flowchart illustrating a method for manufacturing an all-solid-state battery according to embodiments of the present invention.

[0030] Figure 12 is a flowchart specifically explaining the first step of Figure 11.

[0031] Figure 13 is a schematic diagram for explaining the first step of Figure 11.

[0032] Figures 14 and 15 are schematic diagrams for explaining the third step of Figure 11.

[0033] Figure 16 is a perspective view of an all-solid-state battery according to one embodiment.

[0034]

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039] Fig. 1 is a cross-sectional view of an all-solid-state battery (10) according to one embodiment of the present invention. Fig. 2 is a plan view of an all-solid-state battery according to one embodiment of the present invention. Fig. 3 is a cross-sectional view taken along line A-A' of Fig. 2.

[0040] Referring to FIG. 1, an all-solid-state battery (10) according to one embodiment includes a positive electrode layer (100), a negative electrode layer (200) facing the positive electrode layer (100), and a solid electrolyte layer (300) disposed between the positive electrode layer (100) and the negative electrode layer (200). However, the present invention is not limited thereto, and the all-solid-state battery (10) may further include an additional functional layer, such as an adhesion enhancing layer, disposed between the positive electrode layer (100) and the solid electrolyte layer (300) or between the negative electrode layer (200) and the solid electrolyte layer (300).

[0041] 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.

[0042] The positive electrode current collector (110) can provide a reference surface on which the positive electrode active material layer (120) is arranged. The positive electrode 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.

[0043] 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).

[0044] The 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.

[0045] 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.

[0046] 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 전지(10)의 에너지 밀도가 커지고 열안정성이 향상될 수 있다.

[0047] 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 is 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 includes, for example, spray coating, dipping, etc.

[0048] When the positive electrode active material includes nickel (Ni) as a ternary lithium transition metal oxide such as NCA or NCM, for example, the capacity density of the all-solid-state battery (10) can be increased, thereby reducing metal dissolution of the positive electrode active material in a charged state. As a result, the cycle characteristics of the all-solid-state battery (10) in a charged state are improved. Meanwhile, the “cycle characteristics” are characteristics indicating the degree to which the all-solid-state battery (10) is deteriorated by charge / discharge of the all-solid-state battery (10). An all-solid-state battery (10) with high cycle characteristics may have a small degree of deterioration of the all-solid-state battery (10) due to charge / discharge, and an all-solid-state battery (10) with low cycle characteristics may have a large degree of deterioration of the all-solid-state battery (10) due to charge / discharge.

[0049] The shape of the positive electrode active material may include particle shapes such as a sphere or an ellipsoid, for example. The particle size and content of the positive electrode active material are not particularly limited.

[0050] 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).

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] The positive electrode active material layer (120) may include a conductive material. The conductive material may have conductivity without causing a chemical change in the all-solid-state battery (10), thereby increasing the conductivity of the positive electrode active material and the solid electrolyte. The conductive material may include a carbon-based material. The conductive material may include, for example, one or more selected from graphite, carbon black, acetylene black, carbon nanofibers, and carbon nanotubes.

[0056] 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.

[0057] 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 85 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 0.5 parts by weight or more and 1.5 parts by weight or less of the binder.

[0058] 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.

[0059] The positive electrode active material layer (120) may further include additives such as fillers, coating agents, dispersants, and ion conductive aids in addition to the above-described positive electrode active material, solid electrolyte, conductive agent, and binder.

[0060] The negative electrode layer (200) may include a negative electrode current collector (210) and a negative electrode coating layer (220) on the negative electrode current collector (210). The negative electrode current collector (210) may provide a reference surface on which the negative electrode coating layer (220) is disposed. The negative electrode current collector (210) may include, for example, a material that does not react with lithium, i.e., does not form an alloy or a compound with lithium. For example, the negative electrode current collector (210) may include at least one metal selected from the group consisting of copper (Cu), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), and nickel (Ni). The thickness of the negative electrode current collector (210) may be 1 μm to 20 μm, more specifically 5 μm to 15 μm, and more specifically 7 μm to 10 μm.

[0061] 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) may have, for example, a plate shape or a foil shape. Meanwhile, in one embodiment, the negative electrode current collector (210) may be omitted.

[0062] The negative electrode coating layer (220) can allow lithium metal to grow between it and the negative electrode current collector (210) when the all-solid-state battery (10) is charged. The negative electrode coating layer (220) can act as a protective layer for the lithium metal and simultaneously suppress the precipitation and growth of lithium dendrites.

[0063] The cathode coating layer (220) may include a metal and carbon. For example, the cathode 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 cathode 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 cathode coating layer (220) may include a mixture of carbon black and silver (Ag).

[0064] The cathode coating layer (220) may further include additives other than metal and carbon. The cathode coating layer (220) may further include, for example, at least one additive selected from the group consisting of a binder, a filler, a coating agent, a dispersant, and an ion conductive additive.

[0065] The negative electrode coating layer (220) may have a smaller thickness than the positive electrode active material layer (120). The thickness of the negative electrode coating layer (220) may be, for example, 50% or less, 40% or less, 30% or less, 20% or less, 10% or less, or 5% or less of the thickness of the positive electrode active material layer (120). The thickness of the negative electrode coating layer (220) may be, for example, 1 um to 20 um, 2 um to 10 um, or 3 um to 7 um. If the thickness of the negative electrode coating layer (220) is too thin, lithium dendrites formed between the negative electrode coating layer (220) and the negative electrode current collector (210) may cause the negative electrode coating layer (220) to collapse, thereby deteriorating the cycle characteristics of the all-solid-state battery (10). If the thickness of the cathode coating layer (220) increases excessively, the energy density of the all-solid-state battery (10) may decrease and the internal resistance of the all-solid-state battery (10) due to the cathode coating layer (220) may increase, thereby deteriorating the cycle characteristics of the cell.

[0066] Meanwhile, although not shown, a carbon layer may be further included to improve adhesion between the cathode coating layer (220) and the solid electrolyte layer (300).

[0067] 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 having 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 positive electrode active material layer (120) described above.

[0068] 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 positive electrode layer (100), and the second solid electrolyte layer (320) may be adjacent to the negative electrode layer (200).

[0069] Referring to FIG. 3, the first solid electrolyte layer (310) may include a first solid electrolyte. The first solid electrolyte may have a particle shape such as a sphere or an ellipsoid. The first solid electrolyte may include a sulfide-based solid electrolyte. The first 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.

[0070] In one embodiment, the first solid electrolyte is Li 7-a M a PS6-c X c It may be an argyrodite-type compound containing, where 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. Each of a and c may be a real number between 0 and 2.

[0071] 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 first solid electrolyte is, for example, 15 GPa to 35 GPa.

[0072] The first solid electrolyte layer (310) 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 first solid electrolyte layer (310) 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 coating layer (220).

[0073] The second solid electrolyte layer (320) may include a second solid electrolyte. The second solid electrolyte may have a particle shape such as a sphere or ellipsoid.

[0074] The second solid electrolyte may include a sulfide-based solid electrolyte. The description of the second solid electrolyte may be the same as or similar to that described above for the first solid electrolyte. In one embodiment, the second solid electrolyte may have substantially the same composition as the first solid electrolyte. In another embodiment, the second solid electrolyte may have a similar composition to the first solid electrolyte.

[0075] The second solid electrolyte can be in direct contact with the negative electrode coating layer (220). As a result, the second solid electrolyte can suppress lithium dendrites formed between the negative electrode coating layer (220) and the negative electrode current collector (210). The second solid electrolyte can effectively suppress negative electrode side reactions. As a result, the cell performance of the all-solid-state battery (10) according to the present invention can be improved.

[0076] 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. In one embodiment, the first thickness (TK1) may be greater than the second thickness (TK2). For example, the first thickness (TK1) may be [1.1 to 5 times] the second thickness (TK2).

[0077] Referring again to FIGS. 2 and 3, the positive electrode layer (100) and the first solid electrolyte layer (310) may form a positive electrode composite layer (CSH). The negative electrode layer (200) and the second solid electrolyte layer (320) may form a negative electrode composite layer (ASH). The positive electrode composite layer (CSH) may be laminated on the negative electrode composite layer (ASH).

[0078] The area of ​​the cathode composite layer (ASH) and the area of ​​the cathode composite layer (CSH) may be different. Specifically, the area of ​​the cathode composite layer (ASH) may be larger than that of the cathode composite layer (CSH). The cathode composite layer (CSH) may be completely overlapped within the cathode composite layer (ASH).

[0079] In one embodiment of the present invention, the first solid electrolyte layer (310) may have substantially the same area as the positive electrode layer (100). The second solid electrolyte layer (320) may have substantially the same area as the negative electrode layer (200).

[0080] 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 the 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 the second direction (D2). The negative electrode composite layer (ASH) may have a fourth width (WI4) in the second direction (D2). The third width (WI3) may be smaller than the fourth width (WI4).

[0081] The all-solid-state battery (10) according to the present embodiment can be manufactured by forming a negative electrode composite layer (ASH) on a first carrier film, forming a positive electrode composite layer (CSH) on a second carrier film, and then laminating the negative electrode composite layer (ASH) and the positive electrode composite layer (CSH).

[0082]

[0083] Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.

[0084] FIG. 5 is a cross-sectional view of a pouch-type all-solid-state battery (10) according to one embodiment of the present invention. Referring to FIG. 5, the all-solid-state battery (10) may be packaged in a pouch (PCH). More specifically, it may be a form in which an electrode assembly (STC) in which at least one unit cell (UNC) is stacked is packaged in the pouch (PCH). The electrode assembly (STC) may include a unit cell (UNC), a substrate tab (TB) electrically connected to the unit cell, and a lead tab (LTB) connected to the substrate tab. The lead tab (LTB) may be electrically connected to the substrate tab (TB) and protrude outside the pouch. The lead tab (LTB) may be configured to electrically connect the electrode assembly (STC) to the outside of the pouch. The pouch (PCH) may package the electrode assembly (STC) to protect and block the electrode assembly from the outside. The all-solid-state battery packaged in the pouch may be used as an independent unit battery. Multiple pouch-type solid-state batteries can be combined to form a battery module. Multiple battery modules can be combined to form a battery pack. Pouch-type batteries are relatively simple to construct and can be manufactured in a variety of flexible shapes and sizes.

[0085] Referring to FIG. 4, a unit cell (UNC) may include a first electrode, a second electrode having an opposite polarity to the first electrode, and a solid electrolyte layer between the electrodes. The first electrode may include a first electrode current collector (PLT1) and a first electrode coating layer or / and a first electrode active material layer formed on the first electrode current collector (PLT1).

[0086] In one embodiment, a unit cell (UNC) may include an anode, a cathode, and a solid electrolyte layer between the anode and cathode. For example, it may be sequentially stacked in the following order: a cathode, a solid electrolyte layer, an anode, a solid electrolyte layer, and a cathode. As described above, a basic unit including the components that make up a cell may be referred to as a unit cell (UNC).

[0087] Fig. 6 is an enlarged view of the M region of Fig. 5. Referring to Fig. 6, it can be seen that the electrode current collector (STC) and the pouch (PCH) are in contact. The pouch may include a metal layer (MFL), an insulating layer (ISL) formed on the metal layer, and a polymer layer (PLM) formed on the insulating layer. In one embodiment, the pouch may include a metal layer (MFL), an insulating layer (ISL) formed on both sides of the metal layer, and a polymer layer (PLM) formed on each of the insulating layers formed on both sides.

[0088] Each of the metal layer (MFL), the insulating layer (ISL), and the polymer layer (PLM) may have a certain thickness range. The thickness of the pouch may refer to the thickness of the entire metal layer (MFL), the insulating layer (ISL), and the polymer layer (PLM). In one embodiment, the thickness of the pouch (PCH) may be 50 μm to 500 μm, 50 μm to 300 μm, 50 μm to 200 μm, 200 μm to 500 μm, or 100 μm to 200 μm. When the thickness of the pouch increases, the thickness of the stretched portion when the pouch is formed during the process of packaging the all-solid-state battery cell can be maintained constant. Even if the thickness of the all-solid-state battery cell packaged in the pouch increases, deformation of the pouch can be reduced. As a result, the stability of the all-solid-state battery with improved capacity can be improved.

[0089] The metal layer (MFL) may include a metal that maintains mechanical strength and has flexibility. For example, the metal layer may include aluminum (Al). In addition to aluminum, the metal layer may include one or more metals selected from the group consisting of iron (Fe), carbon (C), chromium (Cr), manganese (Mn), and nickel (Ni). Aluminum (Al) may be included in an amount of 90 wt% to 99.9 wt% based on the total mass of the metal layer. A metal layer having a thickness of 20 μm to 300 μm, 30 μm to 40 μm, 50 μm to 100 μm, or 50 μm to 150 μm may be provided.

[0090] FIG. 7 is an enlarged view of the N region of FIG. 7 is an enlarged view of a pouch according to an embodiment of the present invention. In one embodiment, the insulating layer (ISL) may be a layer having a uniform thickness. In another embodiment, as shown in FIG. 7, the insulating layer (ISL) may be formed on the metal layer (MFL) with an irregular thickness. More specifically, the insulating layer (ISL) may include peaks that are irregularly raised. The thickness (ITK) of the insulating layer (ISL) may refer to the distance from the surface where the metal layer (MFL) and the insulating layer come into contact to the most raised peak. In one embodiment, the thickness (ITK) of the insulating layer (ISL) may be 5 μm to 100 μm, 5 μm to 20 μm, 10 μm to 40 μm, 40 μm to 80 μm, or 20 μm to 60 μm. The insulating layer (ISL) can be formed on the surface of the metal layer (MFL) through oxidation treatment. The oxidation treatment method may include, but is not limited to, an electrochemical method. For example, anodizing or alumite may be used. The insulating layer (ISL) may include an oxide of the metal within the metal layer (MFL). For example, the insulating layer (ISL) may include aluminum oxide (Al2O3).

[0091] Referring to FIGS. 6 and 7, the pouch may include a polymer layer (PLM) on an insulating layer (ISL). By including the polymer layer (PLM), the metal layer (MFL) of the pouch may be prevented from being damaged by friction or impact from the outside. In addition, the polymer layer (PLM) may prevent the metal layer (MFL) from directly contacting the electrode assembly (STC) and may have insulating properties. The polymer layer (PLM) may be applied to both surfaces of the metal layer (MFL). The polymer layer (PLM) including different polymer resins may be formed on both surfaces of the metal layer (MFL). The thickness of the polymer layer (PLM) formed on either surface of the metal layer (MFL) may be 30 μm to 300 μm.

[0092] For example, the polymer layer (PLM) may be made of one or more materials selected from the group consisting of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymers, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, polyarylate, and Teflon. In particular, a polyolefin resin such as polypropylene (PP) or polyethylene (PE) may be used. Polypropylene (PP) has excellent mechanical properties such as tensile strength, hardness, rigidity, and heat resistance, and chemical properties such as corrosion resistance, and thus may be suitable for use as the polymer layer. Polyolefin resins can be heat-sealed and are relatively heat-resistant, so they can be used as a material for pouches. The melting point of the polymer contained in the polymer layer (PLM) may be 140°C to 170°C.

[0093] However, all-solid-state batteries may have higher internal cell temperatures on average than conventional lithium-ion batteries. For example, the internal cell temperature of all-solid-state batteries can exceed 170°C. All-solid-state batteries can exhibit higher high-temperature stability due to the use of solid electrolytes. All-solid-state batteries can exhibit superior thermal stability compared to lithium-ion batteries. For example, cell performance can be maintained even at high temperatures exceeding 170°C.

[0094] Even if the cell has high thermal stability, the melting point of the polymer layer (PLM) of the pouch can be exceeded. The polymer layer (PLM) of the pouch can melt, electrically connecting the electrode assembly and the metal layer (MFL) of the pouch. This electrical connection between the pouch and the electrode assembly can cause current to flow through the pouch. This current flow through the pouch can electrically connect the battery, module, and the entire pack, potentially causing a short circuit. This can ultimately lead to accidents such as battery explosion and fire.

[0095] Pouches are prone to mechanical weakness and defects at corners where significant stretching occurs during the packaging process for electrode assemblies. For example, defects may occur at corners surrounding laminated electrode assemblies or corners surrounding protruding lead tabs.

[0096] If the polymer layer (PLM) of the pouch (PCH) is mechanically or thermally damaged, the metal layer may be exposed to the outside. Alternatively, the metal layer (MFL) may come into direct contact with the electrode assembly (STC) or lead tab (LTB), resulting in a short circuit.

[0097] A pouch according to an embodiment of the present invention can maintain stability even when the polymer layer (PLM) is damaged by including an insulating layer (ISL). According to embodiments of the present invention, the stability of a pouch-type battery can be improved by additionally providing an insulating layer (ISL) between the polymer layer (PLM) and the metal layer (MFL). An all-solid-state battery with improved stability can be manufactured by packaging an electrode assembly in a pouch including an insulating layer (ISL).

[0098] Referring to FIG. 10, in one embodiment, the pouch (pch) may include an additional functional layer (FCL) in addition to the metal layer (MFL), the insulating layer (ISL), and the polymer layer (PLM). The functional layer (FCL) may be positioned between the insulating layer (ISL) and the polymer layer (PLM). The functional layer (FCL) may include a material having insulating properties. For example, the functional layer (FCL) is a polymer having a temperature of about 180°C or higher, such as super EP polymers (PSS, LCP, PES, PEI, PI, PAI, PEEK, PAR), fluorine polymers (PTFE, PFA, FEP, ETFE, PVF, PVDF), polyoxymethylene (POM), polyacrylonitrile (PAN), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polyphenylene oxide (PPO), cyclic olefin polymer (COP), polycarbonate (PC), polyvinyl chloride (PVC), polystyrene (PS), polyamide resin, PA6, PA11, PA46, PA66, PA610, P612, PA MXD 6, PBT, polymethyl methacrylate (PMMA), TPE-U, PVAL, PPE, PPS, HBA / HNA-LCP, etc. The functional layer may include at least one material selected from the group consisting of polymer resins having insulating properties that do not melt at high temperatures. In one embodiment, the functional layer may have a thickness of 50 μm to 200 μm. The functional layer (FCL) may improve the insulating performance of the insulating layer (ISL). In addition, it may serve to physically protect / block the pouch metal layer (MFL).

[0099] Referring to FIG. 8, pouches according to embodiments of the present invention may include an insulating layer only in a portion thereof. In a pouch packaging an electrode assembly, the insulating layer may be included only in a portion where stability is vulnerable. In one embodiment, the pouch may include an insulating layer locally only in a portion that contacts the lead tab.

[0100] Fig. 9a is an enlarged view of the X region of Fig. 8, and Fig. 9b is an enlarged view of the Y region of Fig. 8. Referring to Fig. 9a, in the case of the X region that contacts the electrode assembly, the pouch (PCH) may not include an insulating layer (ISL). In contrast, referring to Fig. 9b, in the case of the Y region that contacts the lead tab (LTB), the pouch (PCH) may include an insulating layer (ISL).

[0101] Referring to FIG. 8, the electrode assembly (STC) may include a second electrode disposed on the uppermost or lowermost layer and in contact with the pouch. That is, the second electrode may be in contact with the second electrode current collector (PLT2) and the pouch (PCH). Conversely, an electrode having an electrically opposite polarity to the second electrode and not in contact with the pouch (PCH) may be referred to as a first electrode.

[0102] Each of the first electrode and the second electrode may include a substrate tab (TB) that is electrically connected and extends in one direction. The substrate tab (TB) may be electrically connected to a lead tab (LTB). One lead tab (LTB) may be electrically connected to a plurality of substrate tabs (TB). For example, the connection may be made by welding. More specifically, the lead tab (LTB) may be welded to the substrate tab (TB) or the electrode layer by ultrasonic welding, laser welding, spot welding, or the like.

[0103] In order to make the welding between the electrode and the lead tab (LTB) more solid, a metal chip may be added between the electrode and the lead tab (LTB). The metal chip may be a thin piece of the same material as the substrate tab (TB). For example, the metal chip may be a metal foil, a metal mesh, etc. For example, the metal chip may be an aluminum foil, a copper foil, a SUS foil, etc. In other words, it may be the same material as the electrode current collector. The thickness of the metal chip may be, for example, 2 µm to 10 µm, 2 µm to 7 µm, or 4 µm to 6 µm. By having a thickness in this range, the connection with the lead tab (LTB) can be performed more easily.

[0104] The substrate tab (TB) may refer to a portion of the uncoated portion of the electrode current collector. The uncoated portion may refer to a region excluding a region on the electrode current collector where a coating layer and / or an active material layer exist. The electrode current collector may include a first substrate tab (TB1) extending from a first electrode current collector (plt1) and a second substrate tab (TB2) extending from a second electrode current collector (PLT2).

[0105] A first lead tab (LTB1) may be electrically connected to at least one first substrate tab (TB1). A second lead tab (LTB2) may be electrically connected to at least one second substrate tab (TB2). That is, the first lead tab (LTB1) may be connected only to the first electrode, and the second lead tab (LTB2) may be connected only to the second electrode.

[0106] Referring to FIG. 8, the all-solid-state battery may include a first lead tab (LTB1) connected to a plurality of first electrodes, and a second lead tab (LTB2) connected to a plurality of second electrodes. The pouch may include a first joint in contact with the first lead tab (LTB1), and a second joint in contact with the second lead tab (LTB2).

[0107] More specifically, the second electrode is in contact with the pouch (PCH), but the first electrode is not in contact with the pouch (PCH). In addition, the pouch (PCH) may include an insulating layer (ISL) at the first joint where it is in contact with the first lead tab (LTB1), but may not include an insulating layer (ISL) at the second joint where it is in contact with the second lead tab (LTB2).

[0108] As a result, even if a part of the pouch polymer layer (PLM) is damaged, an insulating layer (ISL) is formed at the first junction that is electrically connected to the first electrode, thereby preventing a short circuit. More specifically, even if the polymer layer (PLM) is melted / damaged and the second electrode current collector (PLT2) and the pouch metal layer (MFL) come into contact, the first lead tab (LTB1) that is connected to the first electrode inside the cell is in contact with the first junction where the insulating layer (ISL) is formed, thereby preventing a short circuit. By preventing the second electrode, which is arranged on the uppermost layer and / or the lowermost layer of the electrode assembly and is in direct contact with the pouch, the first electrode having the opposite polarity, and the pouch metal layer (MFL) from being electrically connected, an electrical short circuit can be prevented. Therefore, the stability of the battery can be improved by preventing unintended electrical connection. The present invention is not limited to the above embodiments, and may include all embodiments that have the same problem-solving principle. For example, contrary to the above embodiments, it is also possible to include an insulating layer in a portion other than the junction where the lead tab and the pouch come into contact.

[0109] Referring to Fig. 8, the first lead tab (ltb1) and the second lead tab (ltb2) may be arranged in opposite directions. For example, when the first lead tab (LTB1) and the second lead tab (LTB2) are arranged in opposite directions, electrical contact can be prevented even if an insulating layer is provided only in the area including the first joint portion based on the first direction (d1).

[0110] As a result, the purpose of preventing electrical short circuits can be achieved even if the insulating layer is provided only in some areas of the pouch.

[0111]

[0112] Figure 11 is a flowchart illustrating a method for manufacturing an all-solid-state battery according to embodiments of the present invention.

[0113] Referring to FIG. 11, a method for manufacturing an all-solid-state battery according to embodiments of the present invention may include a first step (S100) of manufacturing a pouch film, a second step (S200) of manufacturing an electrode assembly, and a third step (S300) of assembling a battery. Through the above-described manufacturing steps, a pouch-type all-solid-state battery having an improved stability structure can be manufactured. In addition, the mass productivity of the all-solid-state battery according to embodiments of the present invention can be further improved.

[0114] Fig. 12 is a flowchart for explaining the first step of Fig. 11. Referring to Fig. 12, the step (S100) of manufacturing a pouch film may include a step of preparing a metal layer (S110), a step of forming an insulating layer by oxidizing the surface of the metal layer (S120), and a step of forming a polymer layer on the insulating layer (S130).

[0115] Figure 13 is a schematic diagram for explaining a step (S120) of forming an insulating layer by oxidizing the surface of a metal layer.

[0116] Referring to FIG. 13, a metal layer (MFL) in a film form may be prepared to manufacture a battery pouch. The metal layer (MFL) may maintain mechanical strength and have flexibility. The metal layer (MFL) may include aluminum (Al). In addition to aluminum, the metal layer (MFL) may include one or more metals selected from the group consisting of iron (Fe), carbon (C), chromium (Cr), manganese (Mn), and nickel (Ni). The metal layer (MFL) may contain 90 wt% to 99.9 wt% of aluminum based on the total mass of the metal layer (MFL). A metal layer having a thickness of 20 μm to 300 μm, 30 μm to 40 μm, 50 μm to 100 μm, or 50 μm to 150 μm may be provided. A metal layer (MFL) having a constant width with respect to a first direction (D1) may be provided. A metal layer (MFL) having a constant width in the first direction (D1) can be prepared in a long roll shape. The width in the first direction (d1) can be adjusted to suit the size of the pouch to be manufactured. The width of the metal layer (MFL) in the first direction (d1) can be the same as the width of the pouch-shaped battery to be manufactured in the first direction (d1).

[0117] A roll-shaped metal layer (MFL) is positioned on a device that moves in one direction, and the wound metal layer (MFL) can be unwound. The unwound metal layer (MFL) can move in a second direction (d2) and an insulating layer formation step can be performed. More specifically, an oxidation treatment step can be performed on the surface of the metal layer (MFL) moving in the second direction (d2).

[0118] An insulating layer can be formed on the surface of the metal layer through a surface oxidizing step (S120). The insulating layer (ISL) may include an oxide of the metal contained in the metal layer. An electrochemical method may be used to oxidize the surface of the metal layer (MFL), but is not limited thereto, and various methods may be applied. For example, anodizing or alumite may be applied. Although not illustrated, the same oxidation treatment step may be performed on both surfaces of the metal layer (MFL). That is, the step of manufacturing the pouch film may include a step of forming an insulating layer on both surfaces of the metal layer. In one embodiment, the thickness of the insulating layer formed on one surface of the metal layer may be 5 μm to 100 μm, 5 μm to 20 μm, 10 μm to 40 μm, 40 μm to 80 μm, or 20 μm to 60 μm. It may be 5 μm to 100 μm.

[0119] Referring to Fig. 13, the step (S120) of oxidizing the surface of the metal layer may include a step of oxidizing the entire area of ​​the metal layer (MFL). In another embodiment, the step of oxidizing only a portion of the metal layer (MFL) may be included. For example, the oxidation treatment may be performed only on an area of ​​a certain width based on the first direction (D1) and may be performed in the second direction (D2). As a result, an insulating layer (ISL) having a certain width based on the first direction (d1) may be formed. That is, by controlling the position and range of the first direction (d1), the position and area at which the insulating layer (ISL) is formed on the metal layer (MFL) may be controlled. A pouch may be manufactured by specifically specifying the position at which the insulating layer (ISL) is formed.

[0120] After the insulating layer forming step (s120), a polymer layer forming step (s130) on the insulating layer may be performed. The polymer layer (PLM) may include one or more polymer resins selected from the group consisting of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymers, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, polyarylate, and Teflon. In particular, a polyolefin resin such as polypropylene (PP) or polyethylene (PE) may be used.

[0121] The polymer layer (PLM) can be formed by laminating a polymer resin onto an insulating layer (ISL). Alternatively, it can be formed by coating. The polymer layer (PLM) can be formed to a thickness of about 30 μm to 300 μm.

[0122] Thereafter, a step (s200) of manufacturing an electrode assembly may be performed. The step (s200) of manufacturing an electrode assembly may include a step of manufacturing a unit cell, a step of stacking the unit cells, and a step of electrically connecting a substrate tab and a lead tab.

[0123] The step of manufacturing a unit cell may include a process of laminating an anode, a cathode, and a solid electrolyte layer between the anode and the cathode. In one embodiment, the unit cell may be in a form in which an anode, a solid electrolyte layer, and a cathode are sequentially laminated. In another embodiment, the unit cell may be in a form in which an anode (anode), a solid electrolyte layer, an anode (cathode), a solid electrolyte layer, and a cathode (cathode) are sequentially laminated. In this case, the anode, the cathode, and the solid electrolyte layer may be laminated with different areas, respectively.

[0124] During the process of laminating the positive and negative electrodes, the direction of the substrate tabs connected to each electrode can be set. For example, the positive and negative substrate tabs can be laminated so that they face opposite directions relative to the first direction (d1). As another example, the positive and negative substrate tabs can be laminated so that they face the same direction relative to the first direction (d1).

[0125] The method may include connecting a plurality of positive electrode substrate tabs to positive lead tabs and connecting a plurality of negative electrode substrate tabs to negative lead tabs. Specifically, the electrodes and substrate tabs may be electrically connected by welding. For example, the electrical connection may be achieved by ultrasonic welding, laser welding, spot welding, or the like.

[0126] The lead tab (LTB) can be connected so as to extend in the direction in which the substrate tab (TB) faces. That is, the directions of the positive lead tab and the negative lead tab can be connected so as to be identical to the directions of the positive substrate tab and the negative substrate tab, respectively.

[0127] An electrode assembly can be manufactured by stacking a plurality of unit cells manufactured as described above. An elastic layer can be additionally provided between the plurality of unit cells.

[0128] Thereafter, a step of assembling a battery (S300) may be performed. The step of assembling a battery may include a step of moving the manufactured electrode assembly onto a pouch and a step of packaging the electrode assembly into the pouch.

[0129] Referring to FIG. 14, electrode assemblies (STC) may be sequentially stacked on the manufactured pouch. More specifically, the electrode assemblies (STC) may be stacked on the pouch (PCH) at regular intervals while the manufactured pouch moves in the second direction (d2). Specifically, the electrode assemblies may be provided on the lower pouch (LPCH).

[0130] In one embodiment, the first lead tab (LTB1) and the second lead tab (LTB2) of the electrode assembly may be arranged to face opposite directions with respect to the first direction (d1).

[0131] Referring to FIG. 15, when electrode assemblies are sequentially stacked and moved on a pouch, a step of the pouch covering the electrode assembly may be performed. Specifically, the upper pouch (UPCH) may be covered on the electrode assembly (STC). The upper pouch (UPCH) and the lower pouch (LPCH) may be the same pouch manufactured in the step (s100) of manufacturing a pouch film.

[0132] The step of assembling the battery (s300) may include a step of cutting the pouch. The step of cutting the pouch may include cutting the pouch to fit the size of the battery. In other words, the step may include cutting the pouch so that the electrode assembly can be packaged according to the shape and size of the battery being manufactured.

[0133] After the upper and lower pouches are cut to fit the size of the battery being manufactured, a pouch sealing step may be performed. The sealing step may include removing some of the generated gas or moisture. The sealing step can seal the electrode assembly from external air or moisture.

[0134] Through the above process, the electrode assembly can be packaged into a pouch. A pouch-type battery manufactured according to one embodiment is illustrated in FIG. 16.

[0135] The method for manufacturing an all-solid-state battery according to the present invention can be implemented in such a way that each step can be performed as a series of continuous processes. According to an embodiment of the present invention, by controlling the area of ​​the insulating layer during the pouch manufacturing step, a pouch suitable for the shape and size of the battery can be manufactured. This allows the production of a battery pouch that is suitable for the shape and size of the battery and has improved stability. Consequently, an effective manufacturing method capable of simultaneously achieving mass production and stability of pouch-type batteries can be provided.

Claims

1. An electrode assembly having at least one unit cell stacked thereon; A lead tab electrically connected to the above unit cell; and An all-solid-state battery comprising a pouch for packaging the above electrode assembly: The unit cell includes a first electrode, a second electrode having a different polarity from the first electrode, and a solid electrolyte between the first and second electrodes, The above all-solid-state battery further includes a first substrate tab extending in one direction from the first electrode, and a second substrate tab extending in the opposite direction from the second electrode, The lead tab includes a first lead tab connected to the first substrate tab and extending outward from the pouch along the one direction, and a second lead tab connected to the second substrate tab and extending outward from the pouch along the opposite direction, The above pouch includes a first joint in contact with the first lead tab, The first joint includes a metal layer, a polymer layer in contact with the first lead tab, and an insulating layer between the metal layer and the polymer layer. An all-solid-state battery, wherein the insulating layer comprises an oxide of the metal in the metal layer.

2. In paragraph 1, The second electrode is disposed on at least one of the uppermost and lowermost portions of the electrode assembly, The above pouch further includes a second joint in contact with the second lead tab, An all-solid-state battery in which the insulating layer is omitted at the second joint.

3. In paragraph 1, The above pouch has the insulating layer omitted in the portion other than the first joint. All-solid-state battery.

4. In paragraph 1, The above metal layer includes aluminum (Al), The above metal oxide is Al2O3, All-solid-state battery.

5. In paragraph 1, The polymer layer comprises a polymer having a melting point of 140°C to 170°C. All-solid-state battery.

6. In paragraph 1, The thickness of the above insulating layer is 5 μm to 100 μm, All-solid-state battery.

7. In paragraph 1, The above solid electrolyte is a sulfide-based solid electrolyte. All-solid-state battery.

8. In paragraph 1, The first joint further comprises a functional layer between the insulating layer and the polymer layer. All-solid-state battery.

9. An electrode assembly having at least one unit cell stacked thereon; A lead tab electrically connected to the above unit cell; and Including a pouch for packaging the above unit cell, The above unit cell includes a positive electrode, a negative electrode, and a solid electrolyte, The above lead tab includes a first lead tab electrically connected to the positive electrode and a second lead tab electrically connected to the negative electrode, The above pouch comprises a polymer layer, an insulating layer, and a metal layer sequentially laminated, The pouch includes a first joint in contact with the first lead tab and a second joint in contact with the second lead tab, An all-solid-state battery, wherein the insulating layer is selectively provided to at least one of the first joint and the second joint.

10. In paragraph 9, The thickness of the above insulating layer is 5 μm to 100 μm, All-solid-state battery.

11. In paragraph 9, The electrode assembly further comprises an elastic layer, All-solid-state battery.

12. In paragraph 9, The above pouch further includes a functional layer between the insulating layer and the polymer layer. All-solid-state battery.

13. In paragraph 9, The polymer layer comprises a polymer having a melting point of 140°C to 170°C. All-solid-state battery.

14. In paragraph 9, The above metal layer includes aluminum (Al). All-solid-state battery.

15. In paragraph 9, The above solid electrolyte is a sulfide-based solid electrolyte. All-solid-state battery.

16. Step of manufacturing pouch film; a step of manufacturing an electrode assembly; and Including the step of assembling the battery, The steps for manufacturing the above pouch film are: Step of preparing a metal layer; A step of forming an insulating layer by oxidizing the surface of the metal layer; and Comprising a step of forming a polymer layer on the insulating layer, Method for manufacturing an all-solid-state battery.

17. In paragraph 16, The insulating layer is formed only on a part of the metal layer, Method for manufacturing an all-solid-state battery.

18. In paragraph 16, The thickness of the above insulating layer is 5 μm to 100 μm, Method for manufacturing an all-solid-state battery.

19. In paragraph 16, The step of forming an insulating layer by oxidizing the surface of the above metal layer Treated with anodizing, Method for manufacturing an all-solid-state battery.

20. In paragraph 16, The steps for assembling the above battery are: A step of moving the manufactured electrode assembly onto the functional pouch film; and a step of packaging the electrode assembly, Each of the above steps is carried out as a series of continuous processes. Method for manufacturing an all-solid-state battery.

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