All-solid-state battery and manufacturing method therefor

Abstract

An embodiment of the present invention provides an all-solid-state battery comprising: a battery cell having a positive electrode layer, a negative electrode layer, a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer, and a current collection part protruding from one side of each of the positive electrode layer and the negative electrode layer; and a pouch part covering the outer circumferential surface of the battery cell and capable of accommodating the battery cell, wherein on one side of the pouch part adjacent to the current collection part, a cut line is formed with a shape in which a plurality of penetration-type slits are arranged to be spaced apart along a preset virtual line.

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] Lithium-ion batteries have reached their limits in terms of performance improvement, and recently, all-solid-state batteries, which replace the electrolyte with a solid electrolyte, have been attracting attention.

[0003] Compared to secondary batteries that generally use liquid electrolytes, all-solid-state batteries do not experience electrolyte decomposition due to overcharging of the battery, and also have high cycle durability and energy density. Since the electrolyte is solid, it is not only safer due to less risk from temperature changes and external shocks, but also has a higher energy density than lithium-ion batteries.

[0004] Meanwhile, it is known that the contact resistance between active material particles responsible for the battery reaction, or between active material particles and solid electrolyte particles, has a significant impact on the internal resistance of the battery in an all-solid-state battery, and a technology is being proposed to suppress the increase in internal resistance by improving the contact between such active material particles, or between active material particles and solid electrolyte particles.

[0005] As a method for manufacturing an all-solid-state battery to improve the contact between these particles, a method for bringing the particles into close contact with each other so that the gaps between the particles are minimized has been proposed, and methods for manufacturing an all-solid-state battery by pressurizing the all-solid-state battery have been proposed.

[0006] In the past, there was a problem that a short circuit occurred between the battery cell of the all-solid-state battery and the pressurizing device during the pressurizing process, or that the solid electrolyte was deformed in the lateral direction during the pressurizing process, resulting in a decrease in the performance of the battery.

[0007] The above-described information disclosed in the background technology of this invention is only intended to improve understanding of the background of the present invention, and therefore may include information that does not constitute prior art.

[0008] The present invention provides an all-solid-state battery in which a cutting line is formed on one side of a pouch portion adjacent to a current collector, thereby making it easy to selectively expose the current collector to the outside according to a process step of the all-solid-state battery.

[0009] The problems addressed by the present invention are not limited to those mentioned above. Other problems and advantages of the present invention not mentioned above can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be appreciated that the problems and advantages addressed by the present invention can be realized by the means and combinations thereof set forth in the claims.

[0010] One aspect of the present invention provides an all-solid-state battery comprising: a battery cell comprising a positive electrode layer; a negative electrode layer; a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer; and a current collector protruding from one side of the positive electrode layer and the negative electrode layer, respectively; and a pouch portion covering an outer circumferential surface of the battery cell and capable of storing the battery cell; wherein a cut line having a shape in which a plurality of through-type slits are spaced apart along a preset virtual line is formed on one side of the pouch portion adjacent to the current collector.

[0011] An all-solid-state battery according to one embodiment of the present invention has a cutting line formed on one side of a pouch portion corresponding to the position of a current collector, thereby selectively exposing a current collector of a battery cell that has completed a pressurizing process to the outside, thereby facilitating electrical connection with a current collector of an adjacent battery cell.

[0012] However, the effects that can be obtained through the present invention are not limited to the effects described above, and other technical effects that are not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0013] The following drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the detailed description of the invention described below, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0014] FIG. 1 is a drawing illustrating an all-solid-state battery with a folded pouch portion according to a first embodiment of the present invention.

[0015] FIG. 2 is a drawing illustrating an all-solid-state battery before the pouch portion according to the first embodiment of the present invention is folded.

[0016] Figures 3a and 3b are diagrams illustrating the process of a pressurizing device pressurizing an all-solid-state battery.

[0017] FIG. 4 is a drawing showing a state in which battery cells according to the first embodiment of the present invention are stacked and combined.

[0018] FIG. 5a and FIG. 5b are plan views of a pouch portion according to the first embodiment of the present invention.

[0019] Figures 6a and 6b are plan views of a pouch portion according to a second embodiment of the present invention.

[0020] Figures 7a and 7b are plan views of a pouch portion according to a third embodiment of the present invention.

[0021] Figures 8a and 8b are plan views of a pouch portion according to a fourth embodiment of the present invention.

[0022] Figure 9 is a flowchart illustrating a method for manufacturing an all-solid-state battery according to embodiments of the present invention.

[0023] One aspect of the present invention provides an all-solid-state battery comprising: a battery cell comprising a positive electrode layer; a negative electrode layer; a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer; and a current collector protruding from one side of the positive electrode layer and the negative electrode layer, respectively; and a pouch portion covering an outer circumferential surface of the battery cell and capable of storing the battery cell; wherein a cut line having a shape in which a plurality of through-type slits are spaced apart along a preset virtual line is formed on one side of the pouch portion adjacent to the current collector.

[0024] Additionally, the cutting line may pass through an area of ​​the pouch portion facing the collector portion.

[0025] In addition, the cutting line may be spaced apart from an area of ​​the pouch portion facing the positive electrode layer and an area of ​​the pouch portion facing the negative electrode layer.

[0026] In addition, the pouch portion includes a first cover body covering one side of the battery cell; and a second cover body formed integrally with the first cover body and covering the other side opposite the one side; a folding line is formed at a boundary between the first cover body and the second cover body, and the pouch portion can be folded based on the folding line to cover both the one side and the other side of the battery cell.

[0027] Additionally, the above virtual line is a straight line, and the above folding line can be perpendicular to the above cutting line.

[0028] Additionally, the first cover body and the second cover body may be symmetrical with respect to the folding line.

[0029] In addition, the cutting line is formed adjacent to an area of ​​the pouch portion corresponding to the area where the current collector is located, and as the cutting line is cut, the current collector can be exposed to the outside of the pouch portion.

[0030] Additionally, the pouch portion may contain at least one of insulating paper and resin.

[0031] Additionally, the battery cell may be a mono cell.

[0032] Another aspect of the present invention provides a method for manufacturing an all-solid-state battery, comprising: a step of manufacturing a battery cell by sequentially stacking a positive electrode layer, a solid electrolyte layer, and a negative electrode layer in one direction; a step of housing the battery cell in a pouch made of an insulating material; a step of pressing the battery cell housed in the pouch in the one direction; and a step of stacking and joining a plurality of pressed battery cells in the one direction; wherein a cutting line having a shape in which a plurality of through-type slits are spaced apart along a preset virtual line is formed on one side of the pouch adjacent to a current collector protruding from one side of the positive electrode layer and the negative electrode layer, respectively.

[0033] In addition, the pouch portion includes a first cover body covering one side of the battery cell; and a second cover body formed integrally with the first cover body and covering the other side opposite the one side; and a folding line may be formed at the boundary between the first cover body and the second cover body.

[0034] In addition, the step of accommodating the battery cell may include a step of settling the battery cell on one surface of the first cover body; a step of folding the first cover body and the second cover body based on the folding line; and a step of adhering one side of the first cover body and one side of the second cover body that face each other while being folded.

[0035] In addition, the step of stacking and bonding may include a step of cutting the cutting line to expose the current collector to the outside; and a step of electrically connecting the current collectors of the stacked battery cells.

[0036] Other aspects, features and advantages other than those described above will become apparent from the following drawings, claims and detailed description of the invention.

[0037] The present invention is capable of various modifications and embodiments. Specific embodiments are illustrated in the drawings and described in detail in the detailed description. The effects and features of the present invention, as well as the methods for achieving them, will become clearer with reference to the embodiments described in detail below, along with the drawings. However, the present invention is not limited to the embodiments disclosed below and can be implemented in various forms.

[0038] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. When describing with reference to the drawings, identical or corresponding components are given the same drawing reference numerals, and redundant descriptions thereof will be omitted.

[0039] In the examples below, singular expressions include plural expressions unless the context clearly indicates otherwise.

[0040] In the examples below, terms such as “include” or “have” mean that a feature or component described in the specification is present, and do not preclude the possibility that one or more other features or components may be added.

[0041] In some embodiments, where implementations are otherwise feasible, specific process sequences may be performed in a different order than described. For example, two processes described in succession may be performed substantially simultaneously, or in a reverse order from the described order.

[0042] For convenience of explanation, the sizes of components in the drawings may be exaggerated or reduced. For example, the sizes and thicknesses of each component shown in the drawings are arbitrarily indicated for convenience of explanation, and thus the following embodiments are not necessarily limited to those shown.

[0043] In the description of each component, when it is described as being formed on or under, on and under include both those formed directly or through the intervention of other components, and the standards for on and under are explained based on the drawings.

[0044] FIG. 1 is a drawing illustrating an all-solid-state battery with a folded pouch portion according to an embodiment of the present invention. FIG. 2 is a drawing illustrating an all-solid-state battery before the pouch portion is folded according to an embodiment of the present invention. FIG. 3a and FIG. 3b are diagrams illustrating a state in which a pressurizing device pressurizes an all-solid-state battery. FIG. 4 is a drawing illustrating a state in which battery cells are stacked and combined according to an embodiment of the present invention. FIG. 5a and FIG. 5b are plan views of a pouch portion according to a first embodiment of the present invention. FIG. 6a and FIG. 6b are plan views of a pouch portion according to a second embodiment of the present invention. FIG. 7a and FIG. 7b are plan views of a pouch portion according to a third embodiment of the present invention. FIG. 8a and FIG. 8b are plan views of a pouch portion according to a fourth embodiment of the present invention.

[0045] Referring to FIG. 1 and FIG. 2, an all-solid-state battery (1) according to the first embodiment of the present invention may include a battery cell (100) and a pouch portion (200).

[0046] Referring to FIG. 1, a battery cell (100) according to the first embodiment of the present invention may include a positive electrode layer (110), a negative electrode layer (120), a solid electrolyte layer (130), and a current collector (140), and the solid electrolyte layer (130) may be disposed between the positive electrode layer (110) and the negative electrode layer (120).

[0047] Specifically, the battery cell (100) can be formed in a shape in which a positive electrode layer (110), a solid electrolyte layer (130), and a negative electrode layer (120) are sequentially stacked.

[0048] In one embodiment, the battery cell (100) may be a mono-cell, but is not limited thereto, and the battery cell (100) may include both a bi-cell and a laminated cell.

[0049] In this specification, a monocell is a single cell composed of a single positive electrode layer (110), a single negative electrode layer (120), and a single solid electrolyte layer (130), and a laminated cell can be interpreted as a cell in which a plurality of monocells are laminated and connected.

[0050] In an optional embodiment, the stacked cell may be a cell of a bi-polar structure.

[0051] The cathode layer (110) according to one embodiment of the present invention may be lithium oxide. Specifically, the cathode layer (110) may be formed of a layered compound such as lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), a compound substituted with one or more transition metals, lithium manganese oxide such as LiMnO3, LiMn2O3, lithium copper oxide, vanadium oxide such as LiV3O8, LiFe3O4, V2O5, Cu2V2O7, Ni-site type lithium nickel oxide, lithium manganese composite oxide, or a combination thereof, but is not limited thereto, and the cathode layer (110) may be formed of various types of cathode materials within the technical concept that can be used as the cathode of a battery.

[0052] According to one embodiment of the present invention, the cathode layer (120) is made of carbon such as non-graphitizable carbon, graphite-based carbon (natural graphite, artificial graphite), Li x Fe2O3(0≤x≤1), Li x WO2(0≤x≤1), Sn x Me 1-x Me' y O z(Me: Mn, Fe, Pb, Ge; Me': Al, B, P, Si, elements of group 1, 2, and 3 of the periodic table, halogens; 0 <x≤1; 1≤y≤3; 1≤z≤8) 등의 금속 복합 산화물, 리튬 금속, 리튬 합금, 규소계 합금, 주석계 합금, SnO, SnO2, PbO, PbO2, Sb2O3, GeO, GeO2, Bi2O3, Bi2O4등의 금속 산화물, 폴리아세틸렌 등의 도전성 고분자, Li-Co-Ni계 재료, 티타늄 산화물, 리튬 티타늄 산화물 또는 이들의 조합 등으로 이루어질 수 있으나, 이에 한정되는 것은 아니며 음극층(120)은 전지의 음극으로 사용될 수 있는 기술적 사상안에서 다양한 종류의 음극재로 이루어질 수 있다.

[0053] The solid electrolyte layer (130) according to one embodiment of the present invention is LGPS (Li 10 Ge P2S 12 ), LSPSCl(Li 9.54 Si 1.74 P 1.44 S 11.7 Cl 0.3 ), sulfide-based materials such as Argyrodite, oxide-based materials such as Perovskite (LLTO), Garnet (LLZO), NASICON, LISICON, or polymer-based materials such as PEO, but is not limited thereto.

[0054] Referring to FIGS. 1 and 2, a current collector (140) according to one embodiment of the present invention protrudes from one side of the positive electrode layer (110) and the negative electrode layer (120), and may include a positive electrode current collector (141) protruding from the positive electrode layer (110) and a negative electrode current collector (142) protruding from the negative electrode layer (120).

[0055] The positive electrode collector (141) is formed integrally with the positive electrode layer (110), and may be formed in a shape that protrudes outward from one side of the positive electrode layer (110), but is not limited thereto. The positive electrode collector (141) may be formed separately from the positive electrode layer (110), and may be formed in a structure that is electrically connected to one side of the positive electrode layer (110).

[0056] Referring to FIG. 4, the positive electrode collector (141) of one battery cell (100) can be electrically connected to the positive electrode collector (141) of another battery cell (100) that is connected in a one-way stack, and specifically, the positive electrode collectors (141) of multiple stacked battery cells (100) can be welded to each other.

[0057] The negative electrode collector (142) is formed integrally with the negative electrode layer (120), and may be formed in a shape that protrudes outward from one side of the negative electrode layer (120), but is not limited thereto. The negative electrode collector (142) may be formed separately from the negative electrode layer (120), and may be formed in a structure that is electrically connected to one side of the negative electrode layer (120).

[0058] The negative electrode collector (142) of one battery cell (100) can be electrically connected to the negative electrode collector (142) of an adjacent battery cell (100), and specifically, the negative electrode collectors (142) of multiple stacked battery cells (100) can be welded to each other.

[0059] The positive electrode collector (141) and the negative electrode collector (142) can be spaced apart from each other on one side of the battery cell (100).

[0060] That is, since the positive electrode collector (141) and the negative electrode collector (142), which are respectively arranged on the same side (right side in FIG. 4) of the battery cell (100), are arranged spaced apart from each other, it is possible to prevent a short circuit from occurring between a bundle of positive electrode collectors (141) welded together and a bundle of negative electrode collectors (142) welded together.

[0061] Referring to FIGS. 1 to 4, a pouch portion (200) according to one embodiment of the present invention covers an outer circumferential surface of a battery cell (100) and is capable of storing the battery cell (100). On one side of the pouch portion (200) adjacent to the current collector (140), a cutting line (230) having a shape in which a plurality of through-type slits are spaced apart along a predetermined virtual line may be formed.

[0062] A pouch portion (200) according to one embodiment of the present invention may include a first cover body (210), a second cover body (220), and an adhesive portion (250).

[0063] The first cover body (210) can cover one side of the battery cell (100), and the second cover body (220) is formed integrally with the first cover body (210) and can cover the other side of the battery cell (100) opposite to the one side.

[0064] In one embodiment, the first cover body (210) may cover one side of the positive electrode layer (110), and the second cover body (220) may cover one side of the negative electrode layer (120), but is not limited thereto, and the first cover body (210) may cover one side of the negative electrode layer (120), and the second cover body (220) may cover one side of the positive electrode layer (110).

[0065] The first cover body (210) and the second cover body (220) can be formed in the same shape and can be arranged symmetrically based on the folding line (240) to be described later.

[0066] In one embodiment, the thickness of the first cover body (210) and the second cover body (220) is preferably 10 μm or more and 1500 μm or less, more preferably 50 μm or more and 800 μm or less, and even more preferably 100 μm or more and 500 μm or less.

[0067] The first cover body (210) and the second cover body (220) can be formed of an insulating layer material that does not pass electricity, and has a volume resistivity It can be formed from ideal materials.

[0068] According to one embodiment of the present invention, the pouch portion (200), specifically the first cover body (210) and the second cover body (220), may contain at least one of insulating paper and resin.

[0069] As an optional embodiment, the first cover body (210) and the second cover body (220) may be made of a resin film containing a resin such as polypropylene (PP), polyethylene (PE), or a copolymer thereof.

[0070] As an optional embodiment, the first cover body (210) and the second cover body (220) may be made of polyvinyl chloride (PVC) vinyl resin, polyacetal resin, polymethyl methacrylate (PMMA) acrylic resin, polycarbonate (PC), polyamide resin, polyurethane resin, polytetrafluoroethylene (PTFE) fluororesin, or a composite resin thereof.

[0071] The width of the pouch portion (200) according to one embodiment of the present invention may be formed to be relatively wider than the width of the outer circumference of the battery cell (100). As a result, the first cover body (210) and the second cover body (220) can be folded based on the folding line (240) to cover the entire outer circumference of the battery cell (100).

[0072] Referring to FIG. 2, the pouch portion (200) before folding based on the folding line (240) can be formed in the shape of a flat film or paper.

[0073] As an optional embodiment, the first cover body (210) is formed in a three-dimensional shape in which a groove is formed corresponding to the shape of one outer surface of the battery cell (100), and the second cover body (220) is formed in a groove corresponding to the shape of the other outer surface of the battery cell (100), so that the battery cell (100) can be seated in the groove.

[0074] However, it is not limited to this, and the first cover body (210) and the second cover body (220) can be formed into various shapes within the technical concept of covering the entire outer surface of the battery cell (100) by folding based on the folding line (240).

[0075] According to one embodiment of the present invention, the cutting line (230) is located on one side of the pouch portion (200) adjacent to the current collector portion (140), and may be formed in a shape in which a plurality of through-type slits are spaced apart along a preset virtual line.

[0076] Referring to FIGS. 5A to 8, when an external force is applied to the pouch portion (200), specifically to the area where the cutting line (230) is formed, the pouch portion (200) can be cut along the cutting line (230) formed along a preset virtual line, and through this, the current collector (140) of the battery cell (100) accommodated inside the pouch portion (200) can be exposed to the outside.

[0077] Accordingly, referring to FIGS. 3a and 3b, before one side of the pouch portion (200) is cut along the cutting line (230), the current collector (140) is located inside the pouch portion (200) made of insulating material, specifically, in the internal space formed by being surrounded by the first cover body (210) and the second cover body (220), so that even when the battery cell (100) is pressurized by the pressurizing device (10), direct contact between the pressurizing device (10) and the current collector (140) is limited, thereby preventing short circuiting and damage to the current collector (140).

[0078] In addition, referring to FIG. 4, by cutting one side of the pouch portion (200) along the cutting line (230) after the pressurizing process to expose the current collector portion (140) to the outside of the pouch portion (200), it is possible to stack battery cells (100) that have completed the pressurizing process and easily weld and join adjacent current collector portions (140).

[0079] Referring to FIGS. 1 to 3b and FIGS. 5a to 8b, a cutting line (230) according to one embodiment of the present invention may be formed to pass through an area of ​​a pouch portion (200) facing a current collector portion (140).

[0080] As a result, when the pouch part (200) is cut along the cutting line (230), the collector part (140) can be exposed to the outside of the pouch part (200).

[0081] Additionally, the cutting line (230) may be spaced apart from an area of ​​the pouch portion (200) facing the positive electrode layer (110) and an area of ​​the pouch portion (200) facing the negative electrode layer (120).

[0082] Due to this, even if the pouch part (200) is cut along the cutting line (230), the area of ​​the battery cell (100) where the positive electrode layer (110) and the negative electrode layer (120) are positioned is limited from being exposed to the outside of the pouch part (200), thereby providing the effect of protecting the positive electrode layer (110), the solid electrolyte layer (130), and the negative electrode layer (120) from the outside by positioning them inside the pouch part (200) while restricting the exposure of only the current collector part (140) to the outside for welding connection of the current collector part (140).

[0083] Referring to FIGS. 1 to 3b and FIGS. 5a to 8b, the cutting line (230) may be formed along a preset virtual line, and the virtual line may be a straight line. However, the present invention is not limited thereto, and the cutting line (230) may be formed along a curve.

[0084]

[0085] Hereinafter, the shape of the cutting line (230) according to the first to fourth embodiments of the present invention will be described.

[0086] Referring to FIGS. 4, 5a, and 5b, the cutting line (230) according to the first embodiment of the present invention is perpendicular to the folding line (240) and can be formed to pass through a region of the pouch portion where the current collector (140) is located. Accordingly, after the pressurizing process of the battery cell (100), the user can cut the cutting line (230) to expose the current collector (140) to the outside of the pouch portion (200), thereby facilitating welding and joining between adjacent current collectors (140).

[0087] Referring to FIG. 4, FIG. 6a, and FIG. 6b, the cutting line (230) according to the second embodiment of the present invention can be formed in a 'ㄷ' shape with one side passing through the positive electrode collector (141) and the negative electrode collector (142) at the same time.

[0088] Referring to FIG. 4, FIG. 7a, and FIG. 7b, two cutting lines (230) according to the third embodiment of the present invention can be formed, and the two cutting lines (230) can be formed in a 'ㄷ' shape passing through one area of ​​the pouch part (200) facing the positive electrode collector part (141) and the other area of ​​the pouch part (200) facing the negative electrode collector part (142), respectively.

[0089] Accordingly, after the pressurizing process of the battery cell (100), the positive electrode collector (141) and the negative electrode collector (142) can be selectively exposed to the outside of the pouch part (200) through the mutually partitioned regions of the pouch part (200) as the two cutting lines (230) are each cut, so that there is an effect of preventing a short circuit between a bundle of positive electrode collectors (141) welded together and a bundle of negative electrode collectors (142) welded together through a region of the pouch part (200) that partitions the region where the positive electrode collector (141) is exposed and the region where the negative electrode collector (142) is exposed.

[0090] Referring to FIGS. 4, 8a, and 8b, two cutting lines (230) according to the fourth embodiment of the present invention can be formed, and one cutting line (230) can be formed in a closed circuit shape in which one side passes through the positive electrode collector (141) and the remaining three sides are formed along the outer periphery of the positive electrode collector (141), and the other cutting line (230) can be formed in a closed circuit shape in which one side passes through the negative electrode collector (142) and the remaining three sides are formed along the outer periphery of the negative electrode collector (142).

[0091] Accordingly, after the pressurizing process of the battery cell (100), the positive electrode collector (141) and the negative electrode collector (142) can be selectively exposed to the outside of the pouch part (200) through the mutually partitioned regions of the pouch part (200) as the two cutting lines (230) are each cut, so that there is an effect of preventing a short circuit between a bundle of positive electrode collectors (141) welded together and a bundle of negative electrode collectors (142) welded together through a region of the pouch part (200) that partitions the region where the positive electrode collector (141) is exposed and the region where the negative electrode collector (142) is exposed.

[0092] Referring to FIGS. 1 and 2, a folding line (240) according to one embodiment of the present invention is formed at the boundary between the first cover body (210) and the second cover body (220), and the pouch portion (200) can be folded based on the folding line (240) to cover both one side of the battery cell (100) and the other side opposite to the one side.

[0093] Specifically, the first cover body (210) and the second cover body (220) can be folded based on the folding line (240) to cover the entire outer periphery of the battery cell (100).

[0094] In one embodiment, a battery cell (100) may be pre-attached to one side of the pouch part (200) before the pouch part (200) is folded based on the folding line (240), and when the pouch part (200) is folded based on the folding line (240), the pouch part (200) may cover the entire outer periphery of the battery cell (100).

[0095] This has the effect of allowing the user to easily cover the battery cell (100) with the pouch portion (200) by folding the folding line (240).

[0096] Referring to FIGS. 1 and 2, an adhesive portion (250) according to one embodiment of the present invention adheres the first cover body (210) and the second cover body (220), and may be made of various materials within the technical concept of being able to adhere the first cover body (210) and the second cover body (220).

[0097] In one embodiment, the adhesive portion (250) may be positioned along the other side of the first cover body (210) opposite to the one side where the folding line (240) is located. As a result, when the second cover body (220) is folded based on the folding line (240), one side of the second cover body (220) is adhered to the other side of the first cover body (210) by the adhesive portion, so that the pouch portion (200) can accommodate the battery cell (100).

[0098] In an optional embodiment, the adhesive portion (250) may be positioned along the other side of the second cover body (220) opposite to the one side where the folding line (240) is located. As a result, when the first cover body (210) is folded based on the folding line (240), one side of the first cover body (210) is adhered to the other side of the second cover body (220) by the adhesive portion, so that the pouch portion (200) can cover the battery cell (100).

[0099] However, it is not limited thereto, and the adhesive portion (250) may be placed in a preset area on an area of ​​the pouch portion (200) where the battery cell (100) is not located.

[0100]

[0101] Hereinafter, a method for manufacturing an all-solid-state battery (1) according to embodiments of the present invention will be described.

[0102] Figure 9 is a flowchart illustrating a method for manufacturing an all-solid-state battery according to one embodiment of the present invention.

[0103] Referring to FIGS. 1 to 4 and 9, a method for manufacturing an all-solid-state battery (1) according to one embodiment of the present invention may include a step (S100) of manufacturing a battery cell by sequentially stacking a positive electrode layer, a solid electrolyte layer, and a negative electrode layer in one direction, a step (S200) of storing the battery cell in a pouch made of an insulating material, a step (S300) of pressurizing the battery cell stored in the pouch in one direction, and a step (S400) of stacking and combining a plurality of pressurized battery cells in one direction.

[0104] Referring to FIGS. 1 and 2, a step (S200) of storing a battery cell according to one embodiment of the present invention may include a step (S210) of placing a battery cell (100) on one surface of a first cover body (210), a step of folding the first cover body (210) and the second cover body (220) based on a folding line (240), and a step of adhering one side of the first cover body (210) and one side of the second cover body (220) that face each other while being folded.

[0105] Specifically, a battery cell (100) in which a positive electrode layer (110), a solid electrolyte layer (130), and a negative electrode layer (120) are sequentially laminated along the above-described direction can be installed on one surface of the first cover body (210) or the second cover body (220). In this case, the battery cell (100) can be positioned so as to be located on the inside of the frame of the first cover body (210) or the second cover body (220).

[0106] In one embodiment, one side of the battery cell (100) can be attached to one side of the first cover body (210) or the second cover body (220).

[0107] The pouch portion (200) can be folded based on the folding line (240) so that the first cover body (210) and the second cover body (220) face each other with the battery cell (100) in between. As a result, the first cover body (210), the battery cell (100), and the second cover body (220) can be sequentially arranged along the one direction.

[0108] An adhesive is placed between one surface of the first cover body (210) and the second cover body (220) facing each other, and by applying pressure to the one surface, the first cover body (210) and the second cover body (220) can be adhered to each other.

[0109] As a result, the outer surface of the battery cell (100) is completely covered by the first cover body (210) and the second cover body (220), so that the pouch part (200) has the effect of protecting the battery cell (100) from the outside.

[0110] Referring to FIGS. 3a and 3b, the step (S300) of pressing a battery cell in one direction according to one embodiment of the present invention may include a step of placing a battery cell (100) stored in a pouch portion (200) on one side of a holder (20) facing a pressurizing device (10), a step of moving the pressurizing device (10) toward the holder (20) to apply pressure to the battery cell (100), and a step of driving the pressurizing device (10) to retreat from the battery cell (100).

[0111] There is no limitation on the type, size, or material of the stand (20), and it should be interpreted that all stands (20) in the form of which battery cells (100) can be placed and fixed are within the scope of the present invention.

[0112] Meanwhile, in one embodiment, the stand (20) may further include a heating unit (not shown in the drawing) capable of applying heat to the battery cell (100). Accordingly, the heating unit applies heat to the battery cell (100) and at the same time, the pressurizing device (10) applies pressure to the battery cell (100), thereby effectively pressurizing the battery cell (100).

[0113] The heating element may be formed of, but is not limited to, a cartridge heater, induction, etc.

[0114] In one embodiment, the heating unit can maintain the temperature of the battery cell (100) at 20 to 400 degrees, and more preferably, the temperature of the battery cell (100) can be maintained at 80 to 200 degrees.

[0115] Accordingly, by the heating unit maintaining the temperature of the battery cell (100) at a preset temperature, the flexibility of the internal materials of the battery cell (100) is improved, thereby preventing product damage caused by stress during the pressurizing process, and by enabling a process of pressurizing at a higher pressure, the homogeneity of the battery cell (100), specifically, the positive electrode layer (110), the solid electrolyte layer (130), and the negative electrode layer (120) can be improved.

[0116] Referring to FIG. 3b, when the pressurizing device (10) is moved toward the side of the holder (20) to apply pressure to the battery cell (100), the battery cell (100) including the current collector (140) is placed inside the pouch portion (200), so that direct contact between the pressurizing device (10) and the holder (20) and the battery cell (100) is limited, thereby preventing the battery cell (100) from being damaged by the pressurizing device (10) and the holder (20) or from being short-circuited.

[0117] Referring to FIGS. 1, 2, and 4, the step (S400) of stacking and combining battery cells along one direction according to one embodiment of the present invention may include a step of exposing the current collector (140) to the outside by cutting the cutting line (230), and a step of electrically connecting the current collectors (140) of the stacked battery cells (100).

[0118] Specifically, since the cutting line (230) of the pouch part (200) that has undergone the pressurization process is cuttable, only the current collector part (140) can be selectively exposed to the outside of the pouch part (200) to perform welding and joining between the current collector parts (140) of the stacked battery cells (100), and the remaining area of ​​the battery cells (100) excluding the current collector part (140) is still positioned inside the pouch part (200), thereby providing the effect of protecting them from the external environment.

[0119] A plurality of battery cells (100) with the cutting line (230) cut off and the current collectors (140) exposed to the outside can be stacked along the above-mentioned one direction, and the positive current collectors (141) of the stacked battery cells (100) can be welded together, and the negative current collectors (142) can be welded together to form a bi-cell or a stacked cell.

[0120] Accordingly, the all-solid-state battery (1) has a cutting line (230) formed on one side of the pouch portion (200) corresponding to the position of the current collector (140), thereby selectively exposing the current collector (140) of the battery cell (100) that has completed the pressurizing process to the outside, thereby facilitating electrical coupling with the current collector (140) of the adjacent battery cell (100).

[0121] Each of the embodiments described above can be implemented independently, but it goes without saying that the structure of each embodiment can be applied in combination to other embodiments.

[0122] While the present invention has been described with reference to the embodiments illustrated in the drawings, these are merely exemplary, and those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible. Therefore, the true scope of technical protection of the present invention should be determined by the technical spirit of the appended claims.

[0123] The specific implementations described in the examples are merely examples and do not limit the scope of the examples in any way. Furthermore, unless specifically stated as "essential," "important," or the like, an element may not be absolutely necessary for the application of the present invention.

[0124] The use of the term "above" and similar referential terms in the specification of embodiments (especially in the claims) may refer to both singular and plural. Furthermore, if a range is described in the embodiments, the invention is intended to include individual values ​​within the range (unless otherwise stated), and is equivalent to describing each individual value within the range in the detailed description.

[0125] Finally, unless there is a clear description of the order or sequence of steps constituting a method according to an embodiment, the steps may be performed in any appropriate order. The embodiments are not necessarily limited to the order in which the steps are described.

[0126] Any use of examples or exemplary terms in the embodiments is merely intended to illustrate the embodiments in detail and is not intended to limit the scope of the embodiments by virtue of such examples or exemplary terms, unless otherwise limited by the claims.

[0127] Additionally, those skilled in the art will appreciate that various modifications, combinations and variations can be made within the scope of the appended claims or their equivalents, depending on design conditions and factors.

[0128] According to one embodiment of the present invention, an all-solid-state battery and a method for manufacturing the same are provided. Furthermore, embodiments of the present invention can be applied to secondary batteries and methods for manufacturing the same used in industry.

[0129] Related national research and development projects

[0130] - Assignment ID: 1415184550

[0131] - Assignment number: 20012349

[0132] - Ministry name: Ministry of Trade, Industry and Energy

[0133] - Project Management (Professional) Agency Name: Korea Institute of Industrial Technology Planning and Evaluation

[0134] - Research Project Name: Development of Technology to Improve Performance and Manufacture Lithium-Based Next-Generation Secondary Battery

[0135] - Research Project Name: Development of All-Solid-State Battery Cell Manufacturing Equipment for 50㎠ or Larger Sizes

[0136] - Contribution rate: 1 / 1

[0137] - Project execution organization name: Mirae Company, Inc.

[0138] Research Institution: January 1, 2023 - December 31, 2023

Claims

1. A battery cell comprising a positive electrode layer; a negative electrode layer; a solid electrolyte layer disposed between the positive electrode layer and the negative electrode layer; and a current collector protruding from one side of the positive electrode layer and the negative electrode layer, respectively; and It includes a pouch portion that covers the outer surface of the battery cell and can store the battery cell; An all-solid-state battery characterized in that a cut line is formed on one side of the pouch portion adjacent to the collector portion, in which a plurality of through-hole slits are spaced apart along a preset virtual line.

2. In paragraph 1, An all-solid-state battery, characterized in that the above-mentioned cutting line passes through a region of the pouch portion facing the current collector.

3. In paragraph 1, An all-solid-state battery, characterized in that the above-mentioned cutting line is spaced apart from an area of ​​the pouch portion facing the positive electrode layer and an area of ​​the pouch portion facing the negative electrode layer.

4. In paragraph 1, The above pouch part, A first cover body covering one side of the above battery cell; and A second cover body formed integrally with the first cover body and covering the other side opposite to the first side; An all-solid-state battery characterized in that a folding line is formed at the boundary between the first cover body and the second cover body, and the pouch part is folded based on the folding line to cover both the one side and the other side of the battery cell.

5. In paragraph 4, An all-solid-state battery, characterized in that the above-mentioned virtual line is a straight line, and the above-mentioned folding line is perpendicular to the above-mentioned cutting line.

6. In paragraph 4, An all-solid-state battery, characterized in that the first cover body and the second cover body are symmetrical with respect to the folding line.

7. In paragraph 2, An all-solid-state device characterized in that the cutting line is formed adjacent to an area of ​​the pouch portion corresponding to an area where the current collector is located, and the current collector is exposed to the outside of the pouch portion as the cutting line is cut.

8. In paragraph 1, An all-solid-state battery, characterized in that the pouch portion contains at least one of insulating paper and resin.

9. In paragraph 1, An all-solid-state battery, characterized in that the above battery cell is a mono cell.

10. A step of manufacturing a battery cell by sequentially laminating a positive electrode layer, a solid electrolyte layer, and a negative electrode layer in one direction; A step of storing the battery cell in a pouch made of insulating material; A step of pressurizing the battery cell stored in the pouch in the above direction; and A step of combining a plurality of pressurized battery cells by stacking them along the one direction; A method for manufacturing an all-solid-state battery, characterized in that a cutting line having a shape in which a plurality of through-type slits are spaced apart along a preset virtual line is formed on one side of the pouch portion adjacent to the current collector protruding from one side of the positive electrode layer and the negative electrode layer, respectively.

11. In paragraph 10, The above pouch part, A first cover body covering one side of the above battery cell; and A second cover body formed integrally with the first cover body and covering the other side opposite to the first side; A method for manufacturing an all-solid-state battery, characterized in that a folding line is formed at the boundary between the first cover body and the second cover body.

12. In paragraph 11, The step of storing the above battery cell is: A step of mounting the battery cell on one surface of the first cover body; A step of folding the first cover body and the second cover body based on the folding line; and A method for manufacturing an all-solid-state battery, characterized by including a step of adhering one side of the first cover body and one side of the second cover body, which face each other while being folded.

13. In paragraph 10, The step of laminating and bonding as described above is: A step of exposing the collector to the outside by cutting the above-mentioned cutting line; and A method for manufacturing an all-solid-state battery, comprising the step of electrically connecting the current collectors of the stacked battery cells.

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