Pouch cell, cell stack and manufacturing method of pouch cell

Abstract

The present invention relates to a pouch cell capable of efficiently discharging gas from inside the pouch to the outside of the pouch so as to delay or prevent the occurrence of venting of the pouch caused by internal gas, etc., during the charging or discharging process of the pouch cell, and a method for manufacturing the same. A pouch cell according to the present invention comprises an electrode assembly and a pouch in which the electrode assembly is disposed inside, and the pouch may include a first layer and a second layer through which gas is permeable, and a barrier layer disposed between the first layer and the second layer and having a plurality of holes formed therein to allow gas to pass through.

Description

Technology Field

[0001] The present invention relates to a pouch cell and a method for manufacturing the same, and more specifically, to a secondary battery pouch cell capable of charging and discharging, a pouch film used in manufacturing a pouch cell, a cell laminate in which a plurality of pouch cells are stacked, a method for manufacturing a pouch film, and a method for manufacturing a pouch cell. Background Technology

[0002] Recently, with rising energy prices due to the depletion of fossil fuels and growing concern over environmental pollution, the demand for eco-friendly alternative energy sources has become an indispensable factor for future life. Accordingly, research on various power generation technologies, such as solar, wind, and tidal power, is ongoing, and there is also significant interest in power storage devices, such as batteries, to utilize this generated electrical energy more efficiently.

[0003] Furthermore, as technological development and demand for battery-powered electronic mobile devices and electric vehicles increase, the demand for batteries as an energy source is rapidly rising, and accordingly, much research is being conducted on batteries capable of meeting various requirements.

[0004] Batteries that store electrical energy can generally be classified into primary and secondary batteries. Primary batteries are disposable, consumable batteries, whereas secondary batteries are rechargeable batteries manufactured using materials capable of repeating oxidation and reduction processes between the electric current and the material. In other words, when a reduction reaction is performed on the material by the electric current, the power is charged, and when an oxidation reaction is performed, the power is discharged; electricity is generated as this charging and discharging cycle is repeatedly performed.

[0005] Secondary batteries can be classified into cylindrical cells, pouch cells, prismatic cells, etc., depending on their shape. Among these, pouch cells can be manufactured by housing an electrode assembly in which a positive electrode, a negative electrode, and a separator are stacked inside a pouch, and sealing the outer part of the pouch.

[0006] Meanwhile, an electrolyte may be contained within the pouch of a pouch cell along with an electrode assembly. At this time, residual moisture in the electrolyte or moisture penetrating from the outside may react with the lithium salt to generate HF (hydrogen fluoride), and gases such as carbon dioxide, carbon monoxide, ethylene, and methane may be generated due to the decomposition of the electrolyte. Additionally, depending on the material of the positive electrode contained in the electrode assembly of the pouch cell, hydrogen and HF may be additionally generated, which can lead to overheating due to overcharging and internal short circuits during the charging and discharging process. Consequently, a large amount of gas may be generated within the pouch. This gas causes the pressure inside the pouch to rise, and the increased pressure may lead to swelling, where the pouch bulges, or venting, where a part of the pouch bursts.

[0007] In conventional pouch cells, pressure increased due to internal gas, and this increased pressure damaged the seal of the sealed portion. Furthermore, the reduced sealing performance of the sealed portion caused a problem where the pouch opened due to pressure, resulting in a venting phenomenon.

[0008] Since pouch cells that have experienced venting cannot function as secondary batteries, there is a need for pouch cells that include a configuration capable of releasing gas from inside the pouch to the outside in order to prevent or delay the occurrence of venting. The problem to be solved

[0009] The objective of the present invention is to provide a pouch cell capable of efficiently discharging gas from inside the pouch to the outside of the pouch so as to delay or prevent the occurrence of venting of the pouch caused by internal gas, etc., during the charging or discharging process of the pouch cell, and a method for manufacturing the same. means of solving the problem

[0010] A pouch cell according to the present invention comprises an electrode assembly and a pouch in which the electrode assembly is disposed therein, wherein the pouch comprises a first layer and a second layer through which gas is permeable, and a barrier layer disposed between the first layer and the second layer and having a plurality of holes formed therein to allow gas to pass through, wherein a portion of the pouch is defined as a cup portion having a surface on which the electrode assembly is placed and a rim surface connected to the rim of the surface, and the holes of the barrier layer may be formed on the rim surface.

[0011] Another part of the above pouch is defined as a terrace portion disposed at the edge of the cup portion, and a hole in the barrier layer may be further formed in the terrace portion.

[0012] The above terrace portion includes a sealing portion that is sealed by sealing, and the hole in the barrier layer may be formed between the cup portion and the sealing portion.

[0013] delete

[0014] The above plurality of holes can be arranged with a certain spacing between them.

[0015] The above pouch may further include a nylon layer disposed between the barrier layer and the second layer and provided with a nylon-based resin.

[0016] A pouch cell according to the present invention comprises an electrode assembly and a pouch in which the electrode assembly is disposed therein, wherein the pouch comprises a permeable layer that is permeable to gas and comprises a polymer, and a barrier layer that is permeable to metal and has a plurality of holes formed therein to allow gas to pass through, wherein a portion of the pouch is defined as a cup portion having a surface on which the electrode assembly is placed and a rim surface connected to the rim of the surface, and the holes of the barrier layer may be formed on the rim surface.

[0017] A pouch film according to the present invention comprises a first layer and a second layer through which gas is permeable, and a barrier layer disposed between the first layer and the second layer, wherein a plurality of holes may be formed in the barrier layer to allow gas to pass through.

[0018] A cell stack according to the present invention comprises a plurality of pouch cells including an electrode assembly and a pouch in which the electrode assembly is disposed inside, wherein the pouch comprises a first layer and a second layer through which gas is permeable, and a barrier layer disposed between the first layer and the second layer and having a plurality of holes formed therein to allow gas to pass through, wherein a portion of the pouch is defined as a cup portion having a surface on which the electrode assembly is placed and a rim surface connected to the rim of the surface, and the plurality of holes may be formed on the rim surface which is a surface other than the surface in contact with an adjacent pouch cell.

[0019] A method for manufacturing a pouch film according to the present invention, which is used for manufacturing a pouch cell, may include the steps of forming a plurality of holes in a metal film containing a metal so that gas can pass through, placing the metal film on one surface of a first film containing a polyolefin resin, placing a second film on one surface of the metal film, and laminating the first film, the metal film, and the second film.

[0020] The second film may include a nylon film disposed on one side of the metal film and comprising a nylon-based resin, and an outer film disposed on one side of the nylon film and comprising an insulating material.

[0021] A method for manufacturing a pouch cell according to the present invention comprises the steps of: forming a plurality of holes in a first region of a metal film containing a metal so that gas can pass through; placing the metal film on one surface of a first film containing a polyolefin resin; placing a second film on one surface of the metal film; laminating the first film, the metal film, and the second film to manufacture a pouch film; forming a second region in the pouch film spaced apart from the first region to form a portion for receiving an electrode assembly; placing the electrode assembly in the formed portion of the pouch film; and sealing the pouch film so that it is sealed. The portion in the pouch film for receiving the electrode assembly is defined as a cup portion having a surface on which the electrode assembly is placed and a border surface connected to the border of the surface, and the plurality of holes may be formed on the border surface. Effects of the invention

[0022] According to a preferred embodiment of the present invention, gas inside the pouch generated during the charging or discharging process of the pouch cell can be efficiently discharged to the outside.

[0023] Accordingly, the safety of the pouch cell can be improved by delaying or preventing the venting phenomenon of the pouch caused by gas inside the pouch.

[0024] In addition, since the gas emitted when multiple pouch cells are stacked does not go toward adjacent pouch cells, the gas can be efficiently discharged.

[0025] In addition, since the holes for gas discharge formed in the barrier layer do not affect the bonding relationship of other components, it is possible to prevent the bonding force between the components forming the pouch cell from weakening.

[0026] In addition, since holes are formed in the barrier layer during pouch film manufacturing, an additional process for incorporating gas discharge components is unnecessary, which can improve the efficiency of the pouch cell manufacturing process.

[0027] The effects according to the present invention are not limited to those exemplified above, and various other effects are included in this specification. Brief explanation of the drawing

[0028] FIG. 1 is a schematic perspective view illustrating a pouch cell according to Example 1 of the present invention. FIG. 2 is a cross-sectional view schematically illustrating a cross-section cut along A-A' of FIG. 1 of the present invention. FIG. 3 is a schematic plan view illustrating the barrier layer of a pouch according to Example 1 of the present invention. FIG. 4 is a schematic perspective view illustrating a pouch cell according to Example 2 of the present invention. FIG. 5 is a cross-sectional view schematically illustrating a cross-section cut along A-A' of FIG. 4 of the present invention. FIG. 6 is a schematic plan view illustrating a cell stack in which a plurality of pouch cells are stacked according to Example 2 of the present invention. FIG. 7 is a flowchart schematically illustrating a method for manufacturing a pouch cell according to Example 3 of the present invention. Specific details for implementing the invention

[0029] Hereinafter, preferred embodiments of the present invention are described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in various different forms and is not limited or restricted by the following embodiments.

[0030] In order to clearly explain the present invention, detailed descriptions of related prior art that are irrelevant to the explanation or that may unnecessarily obscure the essence of the invention have been omitted. Furthermore, when assigning reference numerals to the components of each drawing in this specification, identical or similar reference numerals are assigned to identical or similar components throughout the entire specification.

[0031] Furthermore, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0032] Example 1

[0033] FIG. 1 is a schematic perspective view illustrating a pouch cell (10) according to Example 1 of the present invention, and FIG. 2 is a schematic cross-sectional view illustrating a cross section cut along A-A' of FIG. 1 of the present invention.

[0034] The pouch cell (10) described in the present invention may refer to a secondary battery capable of charging and discharging. Specifically, it may refer to a secondary battery having an electrode assembly (100) comprising a negative electrode, a positive electrode, and a separator disposed inside a pouch (200), and the pouch (200) encloses the electrode assembly (100). More specifically, the pouch cell (10) may refer to a secondary battery in which an electrode assembly (100) comprising a negative electrode, a positive electrode, and a separator is contained together with an electrolyte inside a pouch (200). However, the pouch cell (10) described in Example 1 of the present invention is merely one example and can be applied to other pouch cells, such as those having both ends sealed with caps and the edges surrounded by a pouch.

[0035] The electrode assembly (100) may have a laminated form of a cathode, an anode, and a separator or a wound jelly-roll form, and the pouch (200) may accommodate the electrode assembly (100). Specifically, the pouch (200) may include a cup portion molded to accommodate the electrode assembly (100) and an electrolyte inside.

[0036] Referring to FIG. 1, the electrode lead (300) can be electrically connected to the electrode assembly (100) and positioned to protrude outside the pouch (200). The pouch cell (10) can provide electrical energy to the outside through the electrode lead (300) protruding outside the pouch (200). Thus, the electrode lead (300) can be a conductor.

[0037] The lead film can cover the electrode lead (300) so that the pouch (200) and the electrode lead (300) are insulated from each other. Specifically, the lead film can be placed on both sides of the electrode lead (300) to cover the electrode lead (300). The lead film can be composed of a pair and placed on each side of the electrode lead (300).

[0038] Meanwhile, for insulation of the pouch (200) and the electrode lead (300), the lead film may contain an insulating material. The electrode lead (300) may have a roughly rectangular shape, but is not necessarily limited thereto.

[0039] As the pouch cell (10) undergoes repeated charging and discharging, gas is generated, which can increase the pressure inside the pouch (200). If the pressure inside the pouch (200) increases excessively, venting may occur, causing the pouch cell (10) to lose its function.

[0040] In this regard, the pouch cell (10) according to Embodiment 1 of the present invention may have a hole (2021) formed in a part of the layer constituting the pouch (200) to efficiently discharge gas. That is, the pouch (200) may be composed of a plurality of layers. At this time, among the plurality of layers constituting the pouch (200), gas can move through the hole (2021) in the layer where the hole (2021) is formed, and gas can move through permeation in the other layers. Accordingly, gas generated inside the pouch (200) can be discharged to the outside of the pouch (200) by the internal pressure.

[0041] Referring to FIG. 2, a pouch (200) according to Embodiment 1 of the present invention may include a first layer (201), a barrier layer (202), and a second layer (204). That is, a pouch film comprising the first layer (201), the barrier layer (202), and the second layer (204) may be formed to manufacture the pouch (200). The first layer (201) and the second layer (204) of the pouch (200) may allow gas to pass through, and the barrier layer (202) may be disposed between the first layer (201) and the second layer (204). At this time, a plurality of holes (2021) through which gas can pass may be formed in the barrier layer (202) of the pouch (200). Since the barrier layer (202) is a layer that is difficult for gas to pass through, gas can pass through the barrier layer (202) through the hole (2021) formed in the barrier layer (202).

[0042] However, the layer structure of the pouch (200) described in Example 1 of the present invention is merely one example and may be composed of two layers. For example, the pouch may include a permeable layer made of a polymer such as a polyolefin resin through which gas is permeable, and a barrier layer made of a metal such as stainless steel through which a plurality of holes are formed to allow gas to pass through. In this case, it may be easy to apply to other pouch cells, such as the shape in which both ends are closed with caps as described above and the edges are surrounded by a pouch.

[0043] The first layer (201) of the pouch (200) is made of a polymer and can have heat-sealing properties as the innermost layer of the pouch (200). That is, a portion of it can melt due to heat and have adhesive properties. Therefore, the pouch (200) can be sealed by the first layers (201) facing each other being bonded by sealing. For example, the polymer used to manufacture the first layer (201) of the pouch (200) may be composed of one or more materials selected from the group consisting of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymer, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, polyparaphenylenebenzobisoxazole, polyarylate, Teflon, and glass fiber. In particular, polyolefin resins such as polypropylene (PP) or polyethylene (PE) may be used. Polypropylene (PP) has excellent mechanical properties such as tensile strength, stiffness, surface hardness, wear resistance, and heat resistance, as well as chemical properties such as corrosion resistance, so it can be mainly used to manufacture the first layer (201). Furthermore, it may be composed of unoriented polypropylene (Cated Polypropylene), acid-modified polypropylene (Acid Modified Polypropylene), or polypropylene-butylene-ethylene terpolymer. Here, the acid-modified polypropylene may be MAH PP (maleic anhydride polypropylene). In addition, the first layer (201) may have a single film structure made of any one material, or a composite film structure formed by two or more materials forming layers.

[0044] The second layer (204) of the pouch (200) is made of a polymer as the outermost layer of the pouch (200) and is formed on the outermost side to protect the pouch cell (10) from friction and collision with the outside. Additionally, the second layer (204) can electrically insulate the electrode assembly (100) from the outside. For example, the polymer used to manufacture the second layer (204) of the pouch (200) may be one or more materials selected from the group consisting of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymer, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, polyparaphenylenebenzobisoxazole, polyarylate, Teflon, and glass fiber. In particular, it is preferable to use a polymer such as polyethylene terephthalate (PET) which has wear resistance and heat resistance. Additionally, the second layer (204) may have a single membrane structure made of any one material, or a composite membrane structure formed by two or more materials forming layers.

[0045] The barrier layer (202) of the pouch (200) may include a metal selected from the group consisting of copper (Cu), aluminum (Al), nickel (Ni), iron (Fe), carbon (C), chromium (Cr), manganese (Mn), and alloys containing two or more of these, but is not specifically limited thereto. Preferably, the barrier layer (202) may include a metal selected from aluminum alloy and stainless steel (SUS).

[0046] FIG. 3 is a schematic plan view illustrating a barrier layer (203) of a pouch (200) according to Example 1 of the present invention.

[0047] In the barrier layer (202) of the pouch (200) according to Embodiment 1 of the present invention, a plurality of holes (2021) through which gas can move may be formed. At this time, it is sufficient for the holes (2021) to have a shape that facilitates gas movement, and the size, arrangement, and shape of the holes (2021) may vary. For example, the holes (2021) may be circular, and the plurality of holes (2021) may be arranged with a constant spacing from each other. When the holes (2021) are arranged with a constant spacing from each other, the movement of gas can be distributed relatively uniformly, thus enabling efficient gas discharge. In addition, the process of forming the holes (2021) can be simplified, thereby improving the efficiency of the manufacturing process. Referring to FIG. 3, the plurality of holes (2021) may be formed in the same pattern with a constant spacing from each other.

[0048] For a more specific example, the portion where the hole (2021) is formed in the barrier layer (202) can be a rectangle approximately 17 mm wide and 10 mm high. A large hole may be formed in this portion, or several small holes may be formed. Approximately 1 to 24 holes may be formed, taking into account the strength and gas discharge speed of the pouch (200).

[0049] Meanwhile, the pouch (200) according to Example 1 of the present invention may further include a nylon layer (203). The nylon layer (203) may be disposed between the barrier layer (202) and the second layer (204) and may include a nylon-based resin. By including the nylon layer (203) containing a nylon-based resin, the pouch (200) may have improved moldability due to excellent elongation characteristics.

[0050] The pouch (200) of the pouch cell (10) according to Embodiment 1 of the present invention may include a cup portion (210) and a terrace portion (220). Specifically, an electrode assembly (100) may be accommodated in the cup portion (210), and the terrace portion (220) may be placed on the edge of the cup portion (210). At this time, a hole (2021) may be formed in the terrace portion (220). That is, a hole (2021) may be formed in a portion spaced apart from the portion where the electrode assembly (100) is placed. When a hole (2021) is formed in the terrace portion (220), the gas attempting to move to the outside of the pouch (200) is subject to relatively little interference from the electrode assembly (100), so the gas can be efficiently discharged to the outside of the pouch (200).

[0051] More specifically, the hole (2021) may be formed between the cup portion (210) and the sealing portion (230). In this regard, the terrace portion (220) may include the sealing portion (230). Here, the sealing portion may refer to a part of the terrace portion (220) that is sealed by sealing. That is, the sealing portion may refer to a part of the pouch (200) that is sealed by heat and pressure. When the hole (2021) is formed in the sealing portion (230), the sealing portion (230) may be in a form where the opposing surfaces of the pouch (200) are bonded by sealing. Therefore, there may be relatively insufficient space on the path for gas inside the pouch (200) to move outside the pouch (200). In the pouch cell (10) according to Example 1 of the present invention, since the hole (2021) is formed in the terrace portion (220) excluding the sealing portion (230), gas can be efficiently discharged to the outside of the pouch (200).

[0052] Meanwhile, the cup portion (210) of the pouch (200) can be formed by molding a pouch film composed of multiple layers. A concave cup portion (210) can be formed by pressing the pouch film with a molding device including a punch and a die, etc., so that an electrode assembly (100) can be placed thereon. At this time, the periphery of the unmolded cup portion (210) can become a terrace portion (220).

[0053] The path through which gas is discharged to the outside of the pouch (200) in the pouch cell (10) according to Embodiment 1 of the present invention is as follows. Gas is generated inside the pouch (200) through repeated charging and discharging, and as the gas increases, the internal pressure and concentration of the pouch (200) increase. At this time, the gas passes through the first layer (201) and moves through the hole (2021) formed in the barrier layer (202). Subsequently, the gas can pass through the nylon layer (203) and the second layer (204) and be discharged to the outside of the pouch (200).

[0054] The pouch (200) of the pouch cell (10) according to Embodiment 1 of the present invention can efficiently discharge gas inside the pouch (200) to the outside of the pouch (200) through a hole (2021) formed in the barrier layer (202). In addition, the efficiency of the manufacturing process can be improved as no separate component is added. Furthermore, since it can be manufactured with the same external shape as a conventional pouch cell (10), it can be applied in the same way to a conventional frame, etc.

[0055] The pouch cell (10) according to Example 1 of the present invention can efficiently discharge gas inside the pouch (200) to the outside. Therefore, the occurrence of venting, etc. can be delayed or prevented, thereby improving the stability of the pouch cell (10).

[0056] Example 2

[0057] FIG. 4 is a schematic perspective view illustrating a pouch cell (10') according to Example 2 of the present invention, and FIG. 5 is a schematic cross-sectional view illustrating a cross section cut along A-A' of FIG. 4 of the present invention.

[0058] In the following, a detailed description of the configuration identical to that of the pouch cell (10) according to Embodiment 1 of the present invention is omitted, and the differences are described in detail.

[0059] The pouch cell (10') according to Example 2 of the present invention may have a different location where the hole (2021) is formed compared to the pouch cell (10) according to Example 1 of the present invention.

[0060] Referring to FIGS. 4 and 5, the pouch (200') of the pouch cell (10') according to Embodiment 2 of the present invention may include a cup portion (210') and a terrace portion (220'). In this case, the cup portion (210') of the pouch (200') may include a bottom edge surface (212) and a side surface (211). Specifically, the side surface (211) of the cup portion (210') may be a surface on which the electrode assembly (100) is placed, and the edge surface (212) may be a surface connected to the edge of the side surface (211). If the side surface (211) of the cup portion (210') has a roughly rectangular cross-section, the edge surface (212) may include four sides.

[0061] In the pouch (200') of the pouch cell (10') according to Embodiment 2 of the present invention, a hole (2021) of the barrier layer (202) may be formed on the edge surface (212) of the cup portion (210'). Referring to FIG. 5, the distance between the edge surface (212) of the cup portion (210') and the electrode assembly (100) may be longer than the distance between one side (211) of the cup portion (210') and the electrode assembly (100). Therefore, when the hole (2021) is formed on the edge surface (212) of the cup portion (210'), the gas attempting to move to the outside of the pouch (200') is subject to relatively less interference from the electrode assembly (100), so the gas can be efficiently discharged to the portion of the pouch (200').

[0062] FIG. 6 is a schematic plan view illustrating a cell stack in which a plurality of pouch cells (10') according to Example 2 of the present invention are stacked.

[0063] When a large amount of electrical energy is required, multiple pouch cells (10') can be assembled to form a battery module. At this time, a cell stack in which multiple pouch cells (10') are stacked can be arranged inside the battery module. In this case, gas can be discharged from each of the multiple pouch cells (10') according to Embodiment 2 of the present invention.

[0064] Referring to FIG. 6, in a cell stack in which a plurality of pouch cells (10') according to Embodiment 2 of the present invention are stacked, a plurality of holes (2021) formed in one pouch cell (10') may be formed on a surface other than the surface that contacts an adjacent other pouch cell (10'). That is, the edge surface (212) of the cup portion (210') in which a plurality of holes (2021) are formed in the pouch cell (10') may be a surface that does not contact an adjacent other pouch cell (10').

[0065] When multiple holes (2021) are formed on one side (211) of the cup portion (210'), there is a concern that the gas discharge performance may be degraded by an adjacent pouch cell (10') when gas inside the pouch (200') is discharged. However, in a cell stack in which multiple pouch cells (10') according to Embodiment 2 of the present invention are stacked, when gas inside the pouch (200') of each pouch cell (10') is discharged, interference from other pouch cells (10') is received relatively less, so gas can be efficiently discharged to the outside of the pouch (200').

[0066] The pouch cell (10') according to Embodiment 2 of the present invention can efficiently discharge gas inside the pouch (200') to the outside even when applied to a battery module.

[0067] Example 3

[0068] FIG. 7 is a flowchart schematically illustrating a method for manufacturing a pouch cell according to Example 3 of the present invention.

[0069] A method for manufacturing a pouch cell according to Example 3 of the present invention may include a step of manufacturing a pouch film. First, it may include a step (S1) of forming a plurality of holes (2021) in a metal film containing metal. Specifically, the method for manufacturing a pouch cell may include a step (S1) of forming a plurality of holes (2021) so that gas can pass through a first region of the metal film. At this time, the plurality of holes (2021) may be formed in a part of the metal film.

[0070] Subsequently, a step (S2) of placing a metal film on one side of the first film may be performed. At this time, the first film may include a polyolefin-based resin. A second film may be placed on one side of the metal film placed on one side of the first film. That is, a step (S3) of placing a second film on one side of the metal film may be performed. Thus, one side of the metal film may be in contact with the second film, and the other side of the metal film may be in contact with the first film.

[0071] Subsequently, a step (S4) of manufacturing a pouch film by laminating the first film, the metal film, and the second film may be carried out. Here, lamination may refer to a process of compressing using heat and pressure.

[0072] After the pouch film is manufactured, a step (S5) may be performed to form a second region in the pouch film to form a portion in which the electrode assembly (100) is received. Here, the second region may be spaced apart from the first region in which a plurality of holes (2021) are formed. Therefore, the portion formed in the pouch film may be a portion in which no holes (2021) are formed. Since the first region in which holes (2021) are formed and the second region formed are different portions, the holes (2021) may not be affected by the forming of the pouch film.

[0073] After the pouch film is formed, a step (S6) of placing an electrode assembly (100) on the formed portion of the pouch film may be performed. Subsequently, a step (S7) of sealing the pouch film so that it is sealed may be performed. At this time, the pouch film may be sealed by sealing with heat and pressure.

[0074] Meanwhile, in the method for manufacturing a pouch cell according to Example 3 of the present invention, the second film may include a nylon film and an outer film. Specifically, the nylon film may include a nylon-based resin and may be disposed on one side of a metal film. Additionally, the outer film may include an insulating material and may be disposed on one side of the nylon film.

[0075] The method for manufacturing a pouch cell according to Example 3 of the present invention only adds a process of forming a hole (2021) in a metal film during the manufacturing process of the pouch film, and there is no separate additional process of adding a configuration after the pouch film is sealed. Therefore, a pouch cell (10) capable of emitting gas can be manufactured through a relatively efficient manufacturing process.

[0076] Although the present invention has been described above by limited embodiments and drawings, the present invention is not limited thereto, and various implementations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs. Explanation of the symbols

[0077] 10, 10': Pouch cell 100: Electrode assembly 200, 200': Pouch 201: 1st floor 202: Barrier layer 203: Nylon layer 204: 2nd floor 210, 210': Cup 211: One side 212: Edge surface 220, 220': Terrace section 230: Sealing part 300: Electrode lead 2021: Hall

Claims

Claim 1 A pouch cell comprising: an electrode assembly; and a pouch in which the electrode assembly is disposed therein, wherein the pouch comprises: a first layer and a second layer through which gas is permeable; and a barrier layer disposed between the first layer and the second layer, having a plurality of holes formed therein to allow gas to pass through, wherein a portion of the pouch is defined as a cup portion having a surface on which the electrode assembly is placed and a rim surface connected to the rim of the surface, and the holes of the barrier layer are formed on the rim surface. Claim 2 In claim 1, another part of the pouch is defined as a terrace portion disposed at the edge of the cup portion, and a hole in the barrier layer is further formed in the terrace portion, a pouch cell. Claim 3 In claim 2, the terrace portion includes a sealing portion sealed by sealing, and the hole in the barrier layer is formed between the cup portion and the sealing portion, forming a pouch cell. Claim 4 delete Claim 5 In claim 1, the plurality of holes are arranged at a constant interval from each other, forming a pouch cell. Claim 6 A pouch cell according to claim 1, wherein the pouch further comprises a nylon layer disposed between the barrier layer and the second layer and provided with a nylon-based resin. Claim 7 A pouch cell comprising: an electrode assembly; and a pouch in which the electrode assembly is disposed therein, wherein the pouch comprises: a permeable layer comprising a polymer and permeable to gas; and a barrier layer comprising a metal and having a plurality of holes formed therein to allow gas to pass through, wherein a portion of the pouch is defined as a cup portion having a surface on which the electrode assembly is placed and a rim surface connected to the rim of the surface, and the holes of the barrier layer are formed on the rim surface. Claim 8 delete Claim 9 A cell stack comprising a plurality of pouch cells stacked therein, the electrode assembly and a pouch in which the electrode assembly is disposed therein, wherein the pouch comprises: a first layer and a second layer through which gas is permeable; and a barrier layer disposed between the first layer and the second layer and having a plurality of holes formed therein to allow gas to pass through, wherein a portion of the pouch is defined as a cup portion having a surface on which the electrode assembly is placed and a rim surface connected to the rim of the surface, and the plurality of holes are formed on the rim surface which is a surface other than the surface in contact with an adjacent other pouch cell. Claim 10 delete Claim 11 delete Claim 12 A method for manufacturing a pouch cell comprising: a step of forming a plurality of holes in a first region of a metal film containing a metal so that gas can pass through; a step of placing the metal film on one side of a first film containing a polyolefin resin; a step of placing a second film on one side of the metal film; a step of manufacturing a pouch film by laminating the first film, the metal film, and the second film; a step of forming a second region in the pouch film spaced apart from the first region to form a portion in which an electrode assembly is received; a step of placing the electrode assembly in the formed portion of the pouch film; and a step of sealing the pouch film so that it is sealed, wherein the portion in the pouch film in which the electrode assembly is received is defined as a cup portion having a surface on which the electrode assembly is placed and a border surface connected to the border of the surface, and the plurality of holes are formed in the border surface.

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