Battery cell

Abstract

Battery cells and methods of making the same are disclosed. The battery cell according to the present invention comprises an electrode assembly and a pouch unit surrounding and accommodating the electrode assembly, the pouch unit having an inner layer, an outer layer, and a metal layer disposed between the inner layer and the outer layer, the battery cell comprising: a battery cell main body; a pouch unit having an accommodating portion accommodating the electrode assembly in the pouch unit and the electrode assembly; an electrode lead protruding from the battery cell main body; a first battery cell sealing part formed along a part of the periphery of the battery cell main body and having a part of a pair of first pouch sealing parts extending from the accommodating part, the inner layers facing each other with the electrode lead interposed therebetween and being joined to each other, and a second battery cell sealing part formed along a part of the periphery of the battery cell main body and having a part of a pair of second pouch sealing parts extending from the accommodating part; and a second battery cell sealing part formed along the other part of the periphery of the battery cell main body, the second battery cell sealing part having the other part of the pair of first pouch sealing parts and a pair of second pouch sealing parts extending from the other part of the pair of first pouch sealing parts, the pair of second pouch sealing parts extending from the other part of the pair of first pouch sealing parts, and the pair of second pouch sealing parts extending from the other part of the pair of first pouch sealing parts. The metal layers face each other and are bonded to each other.

Description

Technical Field

[0001] The present invention relates to a battery cell, and more particularly to a battery cell in which a venting direction of internal gas is set when a fire occurs in the battery. Background Art

[0002] Due to the repeated charge and discharge process during the preparation and use of pouch-type battery cells and exposure to harsh environments such as high temperature and high humidity, gas is continuously generated inside the battery cells. This causes the pressure inside the battery cells to rise. If it exceeds the critical value that the bag can withstand, the weak seal of the bag will rupture and the battery cell will be damaged.

[0003] The weak portion of the bag seal may be a sealing portion where the bags facing each other are connected and combined. The bags facing each other are combined by polymerization of the resin, and the bags may be sealed thereby.

[0004] When a battery cell experiences thermal runaway, the gas generated inside the battery cell may be discharged to the outside through the broken seal of the battery cell. The gas generated in the battery cell is high temperature, so it is necessary to control the direction in which the gas generated inside the battery cell is discharged to the outside.

[0005] (Patent Document 1) KR 10-2022-0037348 A Summary of the invention

[0006] Technical issues

[0007] The present invention is directed to solving the above-mentioned problems and other problems.

[0008] Another object of the present invention is to provide a battery cell in which different edges are endowed with different binding forces.

[0009] Another object of the present invention is to provide a battery cell having a sealing portion formed by polymerization or welding of bag sheets on one side and a sealing portion formed by welding of bag sheets on the other side.

[0010] Another object of the present invention is to provide a battery cell in which a discharge direction of gas generated inside a battery when a fire occurs in the battery is set.

[0011] Technical Solution

[0012] In order to achieve the above or other purposes, according to one aspect of the present invention, a battery cell can be provided, which is a battery cell including an electrode assembly and a bag unit surrounding and accommodating the electrode assembly, the bag unit having an inner layer, an outer layer and a metal layer arranged between the inner layer and the outer layer, comprising: a battery cell body, having a housing portion in the bag unit for accommodating the electrode assembly and the electrode assembly; an electrode lead protruding from the battery cell body; a first battery cell sealing portion formed along a portion of the periphery of the battery cell body, having a portion of a pair of first bag sealing portions, the pair of first bag sealing portions extending from the housing portion, the inner layers being opposite to each other and combined with the electrode leads; and a second battery cell sealing portion formed along another portion of the periphery of the battery cell body, having another portion of the pair of first bag sealing portions and a pair of second bag sealing portions, the pair of second bag sealing portions extending from the other portion of the pair of first bag sealing portions, and the metal layers being opposite to each other and combined.

[0013] The melting point of the metal layer may be higher than the melting point of the inner layer.

[0014] The melting point of the outer layer may be higher than the melting point of the inner layer and lower than the melting point of the metal layer.

[0015] The metal layer may be formed of a material including at least one of aluminum (Al), chromium (Cr), iron (Fe), manganese (Mn), copper (Cu), and stainless steel (SUS).

[0016] The inner layer may be formed of a material including at least one of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymer, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, polyphenylene benzoxazole, polyarylate, polytetrafluoroethylene and glass fiber.

[0017] The outer layer may be formed of a material including at least one of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate (PET), polyvinyl chloride, an acrylic-based polymer, polyacrylonitrile, polyimide, and polyamide.

[0018] The pouch unit includes a first pouch surface opposite to the electrode assembly and a second pouch surface facing the outside of the battery cell, and the outer layer may form the second pouch surface.

[0019] The metal layers of the pair of second bag sealing portions may be bonded to each other by welding.

[0020] The inner layer is formed of a material including a polymer, and the inner layers of the pair of first bag sealing parts may be bonded to each other by heat welding.

[0021] The electrode lead may include: a first electrode lead located at one end of the battery cell body; and a second electrode lead located at the other end of the battery cell body.

[0022] The first battery cell sealing part may include two first battery cell sealing parts respectively coupled to the first electrode lead and the second electrode lead.

[0023] The second battery cell sealing portion may include two second battery cell sealing portions connected to the two first battery cell sealing portions and facing each other.

[0024] The receiving portion includes two receiving portions that receive the electrode assembly and face each other, and the pouch unit may include a connection portion that connects the two receiving portions.

[0025] The connecting portion may be formed along one side of the battery cell and closely attached to the electrode assembly.

[0026] The second battery cell sealing portion may include: a second pouch sealing portion head portion extending from the receiving portion; and a second pouch sealing portion tail portion extending from the second pouch sealing portion head portion and folded.

[0027] According to another aspect of the present invention, there is provided a battery cell, comprising: an electrode assembly; and a bag unit having a housing portion surrounding and housing the electrode assembly, the bag unit comprising: a first bag sealing portion, arranged along a portion of the periphery of the electrode assembly and extending from the housing portion, and formed by a 1-1 outer layer, a 1-1 metal layer, an inner layer, a 2-1 metal layer and a 2-1 outer layer being stacked in sequence; and a second bag sealing portion, extending from at least a portion of the first bag sealing portion, and formed by a 2-1 outer layer, a metal layer and a 2-2 outer layer being stacked in sequence.

[0028] The 1-2 outer layer may extend from the 1-1 outer layer, the 2-2 outer layer may extend from the 2-1 outer layer, and the metal layer may extend from the 1-1 metal layer and the 2-1 metal layer.

[0029] The battery cell further includes an electrode lead extending from the electrode assembly and protruding from the pouch unit, and the first pouch sealing part is connected to the electrode lead.

[0030] The receiving portion includes two receiving portions that receive the electrode assembly and face each other, and the pouch unit may include a connection portion that connects the two receiving portions.

[0031] The connecting portion may be formed along one side of the battery cell and closely attached to the electrode assembly.

[0032] Effects of the Invention

[0033] The effects of the battery cell and the method for manufacturing the battery cell according to the present invention are described below.

[0034] According to at least one of the embodiments of the present invention, a battery cell in which different edges are given different binding forces may be provided.

[0035] According to at least one of the embodiments of the present invention, there is provided a battery cell having a sealing portion formed by polymerization or welding of bag sheets on one side and a sealing portion formed by welding of bag sheets on the other side.

[0036] According to at least one of the embodiments of the present invention, there is provided a battery cell in which a discharge direction of gas generated inside a battery when a fire occurs in the battery is set.

[0037] The further applicable scope of the present invention can be clarified by the following detailed description. However, those skilled in the art can clearly understand various changes and modifications within the concept and scope of the present invention, so it should be understood that the detailed description and specific embodiments such as the preferred embodiments of the present invention are only given as examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1a is a three-dimensional diagram of a battery cell according to an embodiment of the present invention;

[0039] Figure 1b A diagram showing a battery cell having a connection portion formed therein;

[0040] Figure 2 is an exploded perspective view of a battery cell according to an embodiment of the present invention;

[0041] Figure 3 To illustrate the cutting along C1-C2 Figure 2 A diagram of a cross section of a bag sheet;

[0042] Figure 4 Shown is a cut along D1-D2 Figure 2 The cross section of the bag piece;

[0043] Figure 5 Shown is a cut along E1-E2 Figure 2 The cross section of the bag piece;

[0044] Figure 6 Shown cutting along B1-B2 Figure 1a The cross section of the battery cell;

[0045] Figure 7 Shown is the cut along F1-F2 Figure 1a The cross section of the battery cell;

[0046] Figure 8 To enlarge the Figure 7 The graph of G;

[0047] Fig. 9 To illustrate the cutting along A1-A2 Figure 1a A diagram of a cross section of a battery cell;

[0048] Fig.10a To enlarge the Fig. 9 FIG. H is a diagram showing the appearance of the second bag sealing portion forming the edge of the battery cell;

[0049] Fig.10b To enlarge the Fig. 9 FIG. H is a diagram showing the appearance of the first bag sealing portion forming the edge of the battery cell;

[0050] Fig.11 To show Fig. 9 A diagram showing a state in which the sealing portion of the second battery cell is folded;

[0051] Fig.12 To enlarge the Fig.11 Figure of I. DETAILED DESCRIPTION

[0052] The embodiments disclosed in this specification are described in detail below with reference to the accompanying drawings. The same or similar components are given the same figure numbers regardless of the figure numbers, and repeated descriptions thereof are omitted. The suffixes "module" and "unit" of the components used in the following description are given or used in combination for the purpose of facilitating the writing of the description, and they themselves do not have mutually distinguishable meanings or functions. Moreover, in describing the embodiments disclosed in this specification, if it is judged that the specific description of the relevant known technology may obscure the purpose of the embodiments disclosed in this specification, the detailed description thereof will be omitted. Moreover, the drawings are only used to make the embodiments disclosed in this specification easy to understand. The technical ideas disclosed in this specification are not limited by the drawings and should be understood to include all changes, equivalents and even substitutes included in the ideas and technical scope of the present invention.

[0053] Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by these terms. These terms are only used to distinguish one component from other components.

[0054] It should be understood that when a certain component is “connected” or “coupled” to another component, it can be directly connected or coupled to the other component, but other components may exist between them. Conversely, when a certain component is “directly connected” or “directly coupled” to another component, it should be understood that there are no other components between them.

[0055] An expression in the singular includes an expression in the plural unless the context clearly indicates otherwise.

[0056] It should be understood that the terms "including" or "having" in this application are intended to specify the features, numbers, steps, actions, constituent elements, parts or their combinations recorded in the specification, and do not preclude the existence or additional possibilities of one or more other features or numbers, steps, actions, constituent elements, parts or their combinations.

[0057] For the sake of convenience, the dimensions of the components shown in the drawings may be exaggerated or reduced. For example, for the sake of convenience, the dimensions and thickness of each component shown in the drawings are arbitrarily shown, and the present description is not necessarily limited to the drawings.

[0058] When a specific embodiment can be implemented in other ways, a specific process sequence can also be performed in a different order from the described sequence. For example, two processes described in succession can be performed substantially simultaneously, or in a reverse order from the described sequence.

[0059] In the following embodiments, when films, regions, components, etc. are connected, it includes not only the case where the films, regions, components are directly connected, but also the case where other films, regions, components are provided between the films, regions, components, etc. to indirectly connect. For example, when films, regions, components, etc. are electrically connected in this specification, it includes not only the case where films, regions, components, etc. are directly electrically connected, but also the case where other films, regions, components, etc. are provided between them to indirectly connect.

[0060] Figure 1a FIG. 1 is a perspective view of a battery cell 10 according to an embodiment of the present invention. Figure 1b A diagram showing a battery cell having a connection portion formed therein. Figure 2 FIG. 1 is an exploded perspective view of a battery cell 10 according to an embodiment of the present invention. Figure 3 To illustrate the cutting along C1-C2 Figure 2 Figure 4 is a diagram of a cross section of a bag sheet.

[0061] Reference Figures 1a to 3 , the battery cell 10 may include an electrode assembly 100. The battery cell 10 may include a pouch unit 300 accommodating the electrode assembly 100. The electrode assembly 100 may be surrounded by the pouch unit 300.

[0062] The electrode assembly 100 may be charged. When the electrode assembly 100 is charged, the electric energy of the electrode assembly 100 may increase. The electrode assembly 100 may be discharged. When the electrode assembly 100 is discharged, the electric energy of the electrode assembly 100 may decrease. The electrode assembly 100 may be referred to as a "jelly roll".

[0063] The electrode assembly 100 may be generally formed in a hexahedral shape. The electrode assembly 100 may be formed in a flat shape. For example, the electrode assembly 100 may be formed in a flat hexahedral shape. For example, the electrode assembly 100 may be formed in a shape extending from one end and continuing to the other end.

[0064] The battery cell 10 may include an electrode lead 200. There may be a plurality of electrode leads 200. For example, the electrode lead 200 may include a first electrode lead 210 and a second electrode lead 220. The electrode lead 200 may be formed of a metal-containing material. The length direction of the battery cell 10 may be parallel to a direction from the first electrode lead 210 toward the second electrode lead 220.

[0065] The electrode lead 200 may be connected to the electrode assembly 100. The first electrode lead 210 may be connected to one end of the electrode assembly 100. The first electrode lead 210 may be located at one end of the battery cell body 11. The second electrode lead 220 may be connected to the other end of the electrode assembly 100. The second electrode lead 220 may be located at the other end of the battery cell body 11.

[0066] The electrode lead 200 may be formed in a shape protruding from the electrode assembly 100. The electrode lead 200 may be formed in a shape protruding from the battery cell body 11. The electrode lead 200 may protrude to the outside of the pouch unit 300. For example, a portion of the electrode lead 200 may extend from the electrode assembly 100 and be accommodated in the pouch unit 300. For example, the other portion of the electrode lead 200 may extend from the portion of the electrode lead 200 and be located outside the battery cell body 11.

[0067] The bag unit 300 may include a bag sheet 301. The bag sheet 301 may be in a sheet shape. The bag sheet 301 may be flexible. The bag sheet 301 may form a face.

[0068] The bag unit 300 may include a first bag surface 305. For example, the bag sheet 301 may form the first bag surface 305. The first bag surface 305 may be a face of the bag sheet 301. The first bag surface 305 may form an inner space of the battery cell 10 and be opposite to the inner space. The first bag surface 305 may be opposite to the electrode assembly 100 and surround the electrode assembly 100.

[0069] The pouch unit 300 may include a second pouch surface 306 . The second pouch surface 306 may be another face of the pouch sheet 301 . The second pouch surface 306 may form an outer face of the battery cell 10 . The second pouch surface 306 may be a face located on the opposite side of the first pouch surface 305 .

[0070] The bag sheet 301 may be formed by stacking a plurality of layers. For example, the bag sheet 301 may include a layer structure 330 .

[0071] The layer structure 330 may include a first layer 331. The first layer 331 may form the first bag surface 305. One side of the first layer 331 may form the first bag surface 305. In this context, the first layer 331 may be referred to as an "inner layer".

[0072] The layer structure 330 may include a second layer 332. The second layer 332 may be opposite to the other side of the first layer 331. One side of the second layer 332 may be in contact with the other side of the first layer 331.

[0073] The layer structure 330 may include a third layer 333. The third layer 333 may be opposite to the other side of the second layer 332. One side of the third layer 333 may be in contact with the other side of the second layer 332. The other side of the third layer 333 may form the second bag surface 306. In this context, the third layer 333 may be referred to as an "outer layer".

[0074] The first layer 331 may be formed of a material including a polymer. For example, the first layer 331 may include a thermopolymerizable compound. When heat is applied to the thermopolymerizable compound, the thermopolymerizable compound may undergo polymerization or cross-linking reaction. In this case, if heat is applied in a state where two different first layers 331 are in contact, the two different first layers 331 may be joined. When heat is applied to the first layer 331, the first layer 331 may be in a molten state, and a pair of first layers 331 may be in contact and fused.

[0075] The first layer 331 may be formed of a material including at least one of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymer, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, polyparaphenylene benzobisoxazole, polyarylate, polytetrafluoroethylene, and glass fiber. The first layer 331 may have a single film structure or a composite film structure composed of two or more substances.

[0076] The second layer 332 may include a metal. For example, the second layer 332 may be formed of a material including at least one of aluminum (Al), chromium (Cr), iron (F2), manganese (Mn), copper (Cu), stainless steel (SUS), and alloys thereof. The second layer 332 may achieve excellent mechanical strength, formability, and moisture barrier effects. In this context, the second layer 332 may be referred to as a "metal layer".

[0077] The third layer 333 may protect the battery cell 10 from the outside. The third layer 333 may be formed as a film. The third layer 333 may be formed of a material including at least one of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate (PET), polyvinyl chloride, acrylic polymer, polyacrylonitrile, polyimide, and polyamide. For example, the third layer 333 may be formed of a material including polyethylene terephthalate (PET).

[0078] The melting point or melting point of the third layer 333 may be higher than the melting point or melting point of the first layer 331. For example, when heat is provided to the third layer 333, the heat may reach the first layer 331 through the second layer 332. In this case, the third layer 333 does not melt, but the first layer 331 may be in a melted state.

[0079] The bag sheet 301 can be formed. For example, the bag sheet 301 can be formed into a shape by performing a press process on the bag sheet 301. For example, the bag unit 300 can be formed by being recessed on one side of the bag sheet 301.

[0080] For example, the bag unit 300 may include a receiving portion 310. The receiving portion 310 may receive the electrode assembly 100. The receiving portion 310 may be opposite to and in contact with the electrode assembly 100. The receiving portion 310 may be recessed in the first bag surface 305. The receiving portion 310 may protrude in the second bag surface 305. For another example, the receiving portion 310 may also be flat and not recessed.

[0081] There may be a plurality of receiving portions 310. For example, there may be two receiving portions 310. The two receiving portions 310 may be formed in two bag sheets 301, respectively. Figure 1a , the two bag sheets 301 can be combined to form two second battery cell sealing portions 16b opposite to each other.

[0082] Reference Figure 1b and Figure 2 , two receiving parts 310 may be formed in one bag sheet 301. The bag unit 300 may include a connecting part 315. The connecting part 315 is located between different receiving parts 310 and can connect different receiving parts 310. In other words, the connecting part 315 is located between two receiving parts 310 and can connect the two receiving parts 310.

[0083] The connecting portion 315 can form the battery cell 10 (refer to Figure 1b For example, the connecting portion 315 may be located opposite to the second battery cell sealing portion 16b.

[0084] The connection portion 315 may form a surface formed on the battery cell 10 (see Figure 1b). The connection portion 315 may be in close contact with the electrode assembly 100. In this sense, the connection portion 315 may be referred to as a "close contact portion".

[0085] For example, the connection portion 315 may be connected to a cooling plate. For example, the heat generated by the electrode assembly 100 may be transferred to the cooling plate through the connection portion 315. Therefore, the connection portion 315 may become a passage for discharging the heat generated by the electrode assembly 100 to the outside.

[0086] The bag unit 300 may include a bag inner region 308 and a bag edge region 309. For example, the bag sheet 301 may be divided into the bag inner region 308 and the bag edge region 309. The bag edge region 309 may be formed in a shape surrounding the bag inner region 308. The bag edge region 309 may be formed along the edge of the bag sheet 301. The receiving portion 310 and the connecting portion 315 may be formed in the bag inner region 308.

[0087] After the electrode assembly 100 is received in the receiving portion 310, the pouch sheet 301 may be folded. The pouch sheet 301 may be folded at the connection portion 315. For example, the electrode assembly 100 may be configured to be received between a pair of receiving portions 310.

[0088] The battery cell 10 may include a battery cell body 11. The battery cell body 11 may refer to a portion of the battery cell 10 where the electrode assembly 100 is located. For example, the battery cell body 11 may include a receiving portion 310 and the electrode assembly 100.

[0089] The battery cell 10 may include a battery cell edge 15. The battery cell edge 15 may form an edge of the battery cell 10. The battery cell edge 15 may be formed or configured along a perimeter of the battery cell body 11. The battery cell edge 15 may be formed by a pouch sheet 301.

[0090] The battery cell 10 may include a battery cell edge portion 16. The battery cell edge portion 16 may be formed or arranged along the battery cell edge 15. The battery cell edge portion 16 may be located or formed between the battery cell edge 15 and the battery cell body 11. The battery cell edge portion 16 may be formed by the pouch sheet 301.

[0091] The battery cell edge portion 16 may be formed by, for example, bonding the pouch sheets 301 to each other. In this sense, the battery cell edge portion 16 may be referred to as a "battery cell sealing portion".

[0092] The bag sheet 301 may include a first bag sealing portion 321. For example, two first bag sealing portions 321 facing each other may be combined with each other to form a first battery cell sealing portion 16a. The first bag sealing portion 321 may form at least a portion of the bag edge region 309. For example, the first bag sealing portion 321 may be formed along the periphery of the bag sheet 301.

[0093] The first battery cell sealing portion 16a may be connected to the electrode lead 200. For example, the electrode lead 200 may be located between two first pouch sealing portions 321 facing each other.

[0094] There may be a plurality of first battery cell sealing portions 16 a. For example, one of the two first battery cell sealing portions 16 a may be connected to the first electrode lead 210. For example, the other of the two first battery cell sealing portions 16 a may be connected to the second electrode 220.

[0095] The bag sheet 301 may include a second bag sealing portion 322 . The second bag sealing portion 322 may extend from the first bag sealing portion 321 and be connected to an edge of the bag sheet 301 .

[0096] For example, a pair of first bag sealing portions 321 facing each other are coupled to each other, and a pair of bag sealing portions 322 facing each other are coupled to each other to form the second battery cell sealing portion 16 b .

[0097] The second bag seal 322 may form at least a portion of the bag edge region 309. For example, the second bag seal 322 may be formed along a portion of the periphery of the bag sheet 301. For example, the second bag seal 322 may be formed along an edge of the periphery of the bag sheet 301 formed in the length direction of the battery cell 10.

[0098] In other words, the second pouch sealing portion 322 may be formed along the remaining edges of the pouch sheet 301 except for the edge where the electrode lead 200 is formed.

[0099] For another example, the second bag sealing portion 322 may be formed at a corner of the bag sheet 301 . For another example, the second bag sealing portion 322 may be formed along a portion of an edge of the bag sheet 301 formed in the length direction of the battery cell 10 .

[0100] The second battery cell sealing portion 16 b may be connected to the first battery cell sealing portion 16 a . The pouch sealing portion 320 may refer to at least one of the first pouch sealing portion 321 and the second pouch sealing portion 322 .

[0101] Figure 4 Shown is a cut along D1-D2 Figure 2 The cross section of the bag piece.

[0102] Reference Figure 4, the first layer 331 of the first bag sealing portion 321 can form the first bag surface 305. Figures 1a to 4 The first battery cell sealing portion 16a may be formed by combining two first bag sealing portions 321 facing each other. For example, the first battery cell sealing portion 16a may be formed by combining the first layers 331 of the two first bag sealing portions 321 facing each other.

[0103] Figure 5 Shown is a cut along E1-E2 Figure 2 The cross section of the bag piece.

[0104] Reference Figure 5 The second bag sealing portion 322 can extend from the first bag sealing portion 321 to the bag sheet 301 (refer to Figure 2 ). For example, the second bag sealing portion 322 may be formed by extending the second layer 332 and the third layer 333 of the first bag sealing portion 321. In other words, the second bag sealing portion 322 may be formed by extending from the first bag sealing portion 321 with the first layer 331 removed.

[0105] The first layer 331 of the first bag seal 321 may form the first bag face 305. The second layer 332 of the second bag seal 322 may form the first bag face 305.

[0106] The second battery cell sealing portion 16b (see Figure 1a and Figure 1b ) can be formed by two mutually opposite first bag sealing parts 321 being bonded to each other and two mutually opposite second bag sealing parts 322 being bonded to each other. For example, the second battery cell sealing part 16b (refer to Figure 1a and Figure 1b ) can be formed by combining a pair of first bag sealing parts 321 with each other and then combining a pair of second bag sealing parts 322 with each other.

[0107] Figure 6 Shown cutting along B1-B2 Figure 1a Cross section of a battery cell.

[0108] Reference Figure 6 , the first bag sealing portion 321 (refer to Figure 2 ) can form the first battery cell sealing portion 16a. The first bag sealing portion 321 (refer to Figure 2 ) may be coupled to the electrode lead 200. For example, the first bag seal portion 321 (refer to Figure 2 ) may be bonded to the electrode lead 200 in a state of being melted by heat. Figure 1a and Figure 1b) in the event of thermal runaway or fire inside the battery cell, the seal of the first battery cell sealing portion 16a may be released.

[0109] Figure 7 Shown is the cut along F1-F2 Figure 1a Cross section of a battery cell.

[0110] Reference Figure 7 , the first bag sealing portion 321 (refer to Figure 2 ) can form the first battery sealing portion 16a. Two first bag sealing portions 321 facing each other (refer to Figure 2 ) can be combined with each other to form a first battery sealing portion 16a.

[0111] Figure 8 To enlarge the Figure 7 Graph of G.

[0112] Reference Figure 8 , two first bag sealing parts 321 facing each other (refer to Figure 2 ) The respective first layers 331 are combined with each other to form the first battery cell sealing portion 16a (refer to Figure 7 ).

[0113] Bag piece 301 (refer to Figure 2 ) may include a first bag sheet portion 301a and a second bag sheet portion 301b opposite to each other. The first bag sheet portion 301a and the second bag sheet portion 301b may form a first bag sealing portion 321.

[0114] The first pouch portion 301a and the second pouch portion 301b may be coupled to each other. For example, the first layer 331 of the first pouch portion 301a may be coupled to the first layer 331 of the second pouch portion 301b.

[0115] Fig. 9 To illustrate the cutting along A1-A2 Figure 1a Figure 2 is a diagram of a cross section of a battery cell.

[0116] Reference Fig. 9 , the second bag sealing portion 322 (refer to Figure 2 ) can form the second battery sealing portion 16b. Two second bag sealing portions 322 facing each other (refer to Figure 2 ) can be combined with each other to form a second battery sealing portion 16b.

[0117] Fig.10a To enlarge the Fig. 9 FIG. H is a diagram showing how the second bag sealing portion forms the edge of the battery cell.

[0118] Reference Fig.10aWhen the first layers 331 of the two mutually opposite first bag sealing parts 321 are bonded to each other and the second layers 332 of the two mutually opposite second bag sealing parts 322 are bonded to each other, the second battery cell sealing part 16b can be formed (refer to Fig. 9 The second bag seal portion 332 may form the battery cell edge 15 (refer to Figure 1a , Figure 1b and Fig. 9 ).

[0119] The first pouch sheet 301a and the second pouch sheet 301b may form a second pouch seal 322. The first pouch sheet portion 301a and the second pouch sheet portion 301b may be bonded to each other. For example, the second layer 332 of the first pouch sheet portion 301a may be bonded to the second layer 332 of the second pouch sheet portion 301b.

[0120] Reference Fig. 9 and Fig.10a The second bag seal part 322 may be formed by extending outward from the first bag seal part 321. That is, after the first layers 331 of the pair of first bag seal parts 321 are coupled to each other, the second layers 332 of the pair of second bag seal parts 322 extending from the pair of first bag seal parts 321 may be coupled by welding or the like.

[0121] Fig.10b To enlarge the Fig. 9 FIG. H is a diagram showing how the first bag sealing portion forms the edge of the battery cell.

[0122] Reference Fig.10b The first bag sealing portion 321 may include a first inner bag sealing portion 3211 and a first outer bag sealing portion 3212. The two first outer bag sealing portions 3211 facing each other may form a battery cell edge 15 (refer to Figure 1a , Figure 1b and Fig. 9 ).

[0123] Reference Fig. 9 and Fig.10b , the second bag sealing part 322 may be located between the first inner bag sealing part 3211 and the first outer bag sealing part 3212. For example, after the first layers 321 of the two first bag sealing parts 321 opposite to each other are combined with each other, at the middle position of the first bag sealing parts 321, the two second layers 332 opposite to each other may be combined with each other by welding or the like to form the second bag sealing part 322.

[0124] Reference Figures 9 to 10b , the outer layer 333 of the first bag seal portion 321 of the first bag sheet portion 301a may be referred to as a "1-1 outer layer". The outer layer 333 of the first bag seal portion 321 of the second bag sheet portion 301b may be referred to as a "2-1 outer layer".

[0125] The metal layer 332 of the first bag seal portion 321 of the first bag sheet portion 301a may be referred to as a “1-1 metal layer.” The metal layer 332 of the first bag seal portion 321 of the second bag sheet portion 301b may be referred to as a “2-1 metal layer.”

[0126] The inner layer 331 of the first bag sheet portion 301 a and the inner layer 331 of the second bag sheet portion 301 b may be combined with each other to form one layer at the first bag sealing portion 321 .

[0127] The outer layer 333 of the second bag seal portion 322 of the first bag sheet portion 301 a may be referred to as a “1-2 outer layer.” The 1-2 outer layer 333 of the second bag seal portion 322 may extend from the 1-1 outer layer 333 of the first bag seal portion 321 .

[0128] The outer layer 333 of the second bag sealed portion 321 of the second bag sheet portion 301 b may be referred to as a “2-2 outer layer.” The 2-2 outer layer 333 of the second bag sealed portion 322 may extend from the 2-1 outer layer 333 of the first bag sealed portion 321 .

[0129] The metal layer 332 of the first pouch sheet portion 301 a and the metal layer 332 of the second pouch sheet portion 301 b may be combined with each other to form one layer at the second pouch sealing portion 322 .

[0130] Fig.11 To show Fig. 9 FIG. 1 is a diagram showing a state in which the sealing portion of the second battery cell is folded.

[0131] Reference Fig.11 , the second battery cell sealing portion 16b (refer to Fig. 9 The second bag sealing portion 322 may include a second bag sealing portion head 3221. The second bag sealing portion head 3221 may be formed by extending from the accommodation portion 310.

[0132] The second bag seal portion 322 may include a second bag seal portion tail portion 3222. The second bag seal portion tail portion 3222 may be formed in a shape folded and extended from the second bag seal portion head portion 3221. The second bag seal portion tail portion 3222 may be opposite to and combined with the second bag seal portion head portion 3221. For example, the second bag seal portion head portion 3221 and the second bag seal portion tail portion 3222 may be arranged along the battery cell 10 (refer to Figure 1a and Figure 1b ) are stacked in the thickness direction. Battery cell 10 (refer to Figure 1a and Figure 1b ) in the thickness direction and the two receiving portions 310 (refer to Figure 2 ) are parallel to the stacking direction.

[0133] Fig.12 To enlarge the Fig.11 Figure of I.

[0134] Reference Fig.12 , the third layer 333 of the second bag sealing portion head 3221 (refer to Fig.10a ) can be connected with the third layer 333 of the tail portion 3222 of the second bag sealing portion (refer to Fig.10a )relatively.

[0135] For example, the third layer 333 of the second bag sealing portion head 3221 (see Fig.10a ) can be connected with the third layer 333 of the tail portion 3222 of the second bag sealing portion (refer to Fig.10a ) relative and combined.

[0136] Reference Figures 1a to 12 The battery cell sealing portion 16 may be divided into two types. For example, the battery cell sealing portion 16 may include a first battery cell sealing portion 16a and a second battery cell sealing portion 16b.

[0137] The first battery cell sealing portion 16a may be coupled to the electrode lead 200. In FIG1 , the first electrode lead 210 and the second electrode lead 220 are located at different sides of the battery cell 10, and thus different first battery cell sealing portions 16a may be formed. For another example, when the first electrode lead 210 and the second electrode lead 220 are located at one side, one first battery cell sealing portion 16a may be formed.

[0138] The second battery cell sealing portion 16 b may be connected to the first battery cell sealing portion 16 a , or may be spaced apart from and opposed to the first battery cell sealing portion 16 a . The second battery cell sealing portion 16 b may not be coupled to the electrode lead 200 .

[0139] The second battery cell sealing portion 16b may be formed along one side of the battery cell body 11. For another example, the second battery cell sealing portion 16b may be formed along a portion of one side of the battery cell body 11.

[0140] The second battery cell sealing portion 16b may be formed along two sides of the battery cell body 11. For example, two battery cell sealing portions 16b may be respectively formed along two sides of the battery cell body 11. For example, the two battery cell sealing portions 16b may be located opposite to each other.

[0141] The battery cell sealing part 16 may include a pair of first pouch sealing parts 321 formed along the periphery of the battery cell body 11 and coupled to each other with a first layer 331. The battery cell sealing part 16 may include a pair of second pouch sealing parts 322 extending from a portion of the pair of first pouch sealing parts 321 and coupled to each other with a second layer 332. The first pouch sealing part 321 may be formed extending from the receiving part 310.

[0142] The first battery cell sealing part 16a may be formed along a portion of the circumference of the battery cell body 11. The first battery cell sealing part 16a may include a portion of a pair of first pouch sealing parts 321. The first battery cell sealing part 16a may be connected to the electrode lead 200.

[0143] The second battery cell sealing portion 16b may include another portion of the pair of first pouch sealing portions 321. The second battery cell sealing portion 16b may include a pair of second pouch sealing portions 322 extending from another portion of the pair of first pouch sealing portions 321. The second layers 332 of the pair of second pouch sealing portions 322 may be opposite to and combined with each other.

[0144] The melting point of the first layer 331 may be, for example, 140° C. to 160° C. For example, the melting point of the second layer 332 may be, for example, above 1000° C. Therefore, in the event of a fire or thermal runaway inside the battery cell 10, the first battery cell sealing portion 16a ruptures before the second battery cell sealing portion 16b, and the heat or gas generated inside the battery cell 10 may be discharged to the outside through the ruptured first battery cell sealing portion 16a.

[0145] The exhaust direction of gas or heat generated inside the battery cell 10 may be determined by configuring the first battery cell sealing portion 16a and the second battery cell sealing portion 16b. For example, in a case where the first battery cell sealing portion 16a is formed on the electrode lead 200 and the second battery cell sealing portion 16b is connected to the first battery cell sealing portion 16a, gas or heat generated inside the battery cell 10 may be exhausted to the outside in the protruding direction of the electrode lead 200.

[0146] That is, in the event of a fire or thermal runaway inside the battery cell 10 , a venting direction of the battery cell 10 may be set. Thus, a battery module including a plurality of stacked battery cells 10 may be designed to be safer.

[0147] The above-described embodiments or other embodiments of the present invention are not mutually exclusive or distinguishable. The above-described embodiments or other embodiments of the present invention may be used or combined in combination.

[0148] The present invention can be embodied in other specific ways within the scope of the spirit and essential features of the present invention, which is obvious to those skilled in the art. The above detailed description shall not be interpreted restrictively in all aspects, but shall be regarded as illustrative. The scope of the present invention shall be determined by a reasonable interpretation of the attached claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention.

Claims

1. A battery cell, as a battery cell comprising an electrode assembly and a pouch unit surrounding and accommodating the electrode assembly, wherein the pouch unit has an inner layer, an outer layer, and a metal layer disposed between the inner layer and the outer layer, comprising: A battery cell body, comprising a receiving portion in the bag unit for receiving the electrode assembly and the electrode assembly; an electrode lead protruding from the battery cell body; a first battery cell sealing portion formed along a portion of the periphery of the battery cell body, having a portion of a pair of first bag sealing portions, the pair of first bag sealing portions extending from the accommodation portion, the inner layers facing each other and coupled via the electrode lead; as well as The second battery cell sealing portion is formed along another portion of the periphery of the battery cell body, and has another portion of the pair of first bag sealing portions and a pair of second bag sealing portions, the pair of second bag sealing portions extending from the other portion of the pair of first bag sealing portions, and the metal layers are opposite to and combined with each other.

2. The battery cell according to claim 1, wherein: The melting point of the metal layer is higher than the melting point of the inner layer.

3. The battery cell according to claim 2, wherein: The melting point of the outer layer is higher than the melting point of the inner layer and lower than the melting point of the metal layer.

4. The battery cell according to claim 1, wherein: The metal layer is formed of a material including at least one of aluminum (Al), chromium (Cr), iron (Fe), manganese (Mn), copper (Cu), and stainless steel (SUS).

5. The battery cell according to claim 1, wherein: The inner layer is formed of a material including at least one of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate, polyvinyl chloride, acrylic polymer, polyacrylonitrile, polyimide, polyamide, cellulose, aramid, nylon, polyester, polyphenylene benzoxazole, polyarylate, polytetrafluoroethylene and glass fiber.

6. The battery cell according to claim 1, wherein: The outer layer is formed of a material including at least one of polyethylene, polypropylene, polycarbonate, polyethylene terephthalate (PET), polyvinyl chloride, acrylic-based polymer, polyacrylonitrile, polyimide, and polyamide.

7. The battery cell according to claim 1, wherein: The pouch unit includes a first pouch surface opposite to the electrode assembly and a second pouch surface facing the outside of the battery cell, The outer layer forms the second bag face.

8. The battery cell according to claim 1, wherein: The metal layers of the pair of second bag sealing portions are bonded to each other by welding.

9. The battery cell according to claim 1, wherein: The inner layer is formed of a material including a polymer. The inner layers of the pair of first bag sealing portions are bonded to each other by heat welding.

10. The battery cell according to claim 1, wherein: The electrode lead comprises: A first electrode lead, located at one end of the battery cell body; and The second electrode lead is located at the other end of the battery cell body.

11. The battery cell according to claim 10, wherein: The first battery cell sealing part includes two first battery cell sealing parts respectively coupled to the first electrode lead and the second electrode lead.

12. The battery cell according to claim 11, wherein: The second battery cell sealing portion includes two second battery cell sealing portions connected to the two first battery cell sealing portions and facing each other.

13. The battery cell according to claim 1, wherein: The receiving portion includes two receiving portions that receive the electrode assembly and are opposite to each other. The bag unit includes a connection portion connecting the two receiving portions.

14. The battery cell according to claim 13, wherein: The connecting portion is formed along one side of the battery cell and is closely attached to the electrode assembly.

15. The battery cell according to claim 13, wherein: The second battery cell sealing portion comprises: a second bag sealing portion head extending from the receiving portion; and The second bag sealing portion tail portion is extended from the second bag sealing portion head portion and folded.

16. A battery cell comprising: Electrode assembly; as well as a bag unit having a receiving portion surrounding and receiving the electrode assembly, The bag unit comprises: a first bag sealing portion, arranged along a portion of the periphery of the electrode assembly and extending from the accommodation portion, and formed by sequentially stacking a 1-1 outer layer, a 1-1 metal layer, an inner layer, a 2-1 metal layer, and a 2-1 outer layer; as well as The second bag sealing portion extends from at least a portion of the first bag sealing portion and is formed by laminating the 2-1 outer layer, the metal layer, and the 2-2 outer layer in this order.

17. The battery cell according to claim 16, wherein: The 1-2 outer layer extends from the 1-1 outer layer, The 2-2 outer layer extends from the 2-1 outer layer, The metal layer extends from the 1-1 metal layer and the 2-1 metal layer.

18. The battery cell according to claim 16, wherein: Also included is an electrode lead extending from the electrode assembly and protruding from the pouch unit, The first bag seal is connected to the electrode lead.

19. The battery cell according to claim 16, wherein: The receiving portion includes two receiving portions that receive the electrode assembly and are opposite to each other. The bag unit includes a connection portion connecting the two receiving portions.

20. The battery cell according to claim 19, wherein: The connecting portion is formed along one side of the battery cell and is closely attached to the electrode assembly.

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