Pouch-type battery cell and battery module including the same

Abstract

A pouch-type battery cell according to the present invention includes electrode assemblies in which positive and negative electrode plates are repeatedly arranged to face each other with a separator sandwiched therebetween; a pouch exterior material that hermetically houses the electrode assemblies; and electrode leads that connect to a bundle of electrode tabs extending from the electrode assemblies inside the pouch exterior material and protrude to the outside of the pouch exterior material, wherein the electrode leads include first and second electrode leads that extend in the same direction facing each other and have the same polarity, and a burst seal member is provided between the first and second electrode leads, one side of which is bonded to the first electrode lead and the other side of which is bonded to the second electrode lead.

Description

[Technical Field]

[0001] The present invention relates to a secondary battery, and more particularly to a pouch-type battery cell that generates less heat under high-speed charging or high-power conditions and has excellent safety against thermal events, and a battery module including the same.

[0002] This application claims priority based on Korean Patent Application No. 10-2022-0168017 filed on December 5, 2022 and Korean Patent Application No. 10-2023-0036123 filed on March 20, 2023, and the contents disclosed in the specifications and drawings of those applications are incorporated herein in their entirety. [Background technology]

[0003] As technological development and demand for various mobile devices, electric vehicles, energy storage systems (ESS), etc. increases, interest in and demand for secondary batteries as an energy source is rapidly increasing. Previously, nickel-cadmium batteries or nickel-metal hydride batteries were used as secondary batteries, but this year, lithium secondary batteries are becoming more popular because they have almost no memory effect compared to nickel-based secondary batteries, can be charged and discharged freely, have an extremely low self-discharge rate, and have a high energy density.

[0004] Such lithium secondary batteries mainly use lithium-based oxides and carbon materials as the positive and negative electrode active materials, respectively, and include an electrode assembly in which a positive electrode plate and a negative electrode plate, each coated with the positive and negative electrode active materials, are arranged with a separator sandwiched between them, and an exterior material, i.e., a battery case, that hermetically houses the electrode assembly together with an electrolyte.

[0005] Depending on the shape of the exterior, lithium secondary batteries can be divided into can-type secondary batteries, in which an electrode assembly is housed in a metal can, and pouch-type secondary batteries, in which an electrode assembly is housed in an aluminum laminated sheet pouch. These secondary batteries are generally manufactured by injecting an electrolyte solution into a housing in which the electrode assembly is housed, and then sealing the housing.

[0006] Pouch-type secondary batteries are preferred when manufacturing medium- to large-sized battery modules due to their advantages of being easier to stack, being lighter, and having a higher energy density relative to volume compared to other types of secondary batteries.

[0007] 1 and 2, the pouch-type secondary battery 1 may include an electrode assembly, electrode tabs, electrode leads, and a pouch exterior. The electrode tabs may include a positive electrode tab extending from the positive electrode plate of the electrode assembly and a negative electrode tab extending from the negative electrode plate of the electrode assembly. The positive electrode tab and the negative electrode tab may be aligned in a predetermined direction and then joined to the corresponding electrode leads by resistance welding, ultrasonic welding, laser welding, or the like. The electrode leads may be exposed to the outside of the pouch exterior and function as electrode terminals of the pouch-type secondary battery.

[0008] On the other hand, in conventional pouch-type secondary batteries, electrode tabs are all connected to a single electrode lead, as shown in Figure 2. This structure, in which multiple electrode tabs (positive or negative electrode tabs) are connected to a single electrode lead, causes a bottleneck in the current flow, which becomes an obstacle during high-speed charging and leads to problems such as increased heat generation under high-power conditions.

[0009] Furthermore, when a pouch-type battery cell experiences thermal runaway, gas is generated inside the cell. If the internal pressure of the pouch-type battery cell exceeds the limit pressure that the sealing part S can withstand and the sealing part S opens, the high pressure can cause high-temperature gas and particles to be explosively ejected all at once (here, particles refer to electrode pieces or active material detached from the electrode assembly). The high-pressure, high-temperature gas and particles ejected from the pouch-type battery cell can cause significant thermal damage to other adjacent pouch-type battery cells and the surrounding environment. Therefore, there is a need to develop a pouch-type battery cell that can prevent explosions during thermal events. Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention has been made in view of the above problems, and aims to provide a pouch-type battery cell that generates little heat under high-speed charging conditions and high-power conditions and has excellent safety against thermal events, and a battery module including the same.

[0011] However, the technical problems that the present invention aims to solve are not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description of the invention. [Means for solving the problem]

[0012] A pouch-type battery cell according to the present invention includes electrode assemblies in which positive and negative electrode plates are repeatedly arranged to face each other with a separator sandwiched therebetween; a pouch exterior material that hermetically houses the electrode assemblies; and electrode leads that connect to a bundle of electrode tabs extending from the electrode assemblies inside the pouch exterior material and protrude to the outside of the pouch exterior material, the electrode leads including a first electrode lead and a second electrode lead that face each other, extend in the same direction, and have the same polarity, and a burst seal member is provided between the first electrode lead and the second electrode lead so that one side of the burst seal member is joined to the first electrode lead and the other side of the burst seal member is joined to the second electrode lead.

[0013] The electrode tab bundle may be divided into two bundles, including a first electrode tab bundle and a second electrode tab bundle, and the first electrode tab bundle may be configured to connect to the first electrode lead, and the second electrode tab bundle may be configured to connect to the second electrode lead.

[0014] The first electrode lead and the second electrode lead may be configured to be separated from each other inside the pouch outer casing.

[0015] The pouch exterior material includes a sealing portion formed by heat welding the peripheral portion, and the sealing portion may be provided with a first lead film that joins the first electrode lead to the pouch exterior material, and a second lead film that joins the second electrode lead to the pouch exterior material.

[0016] The bonding strength of the burst seal member may be set to be weaker than the bonding strength of the first lead film or the second lead film.

[0017] The burst seal member may extend outside the pouch outer material along with the first electrode lead and the second electrode lead.

[0018] The burst seal member may be made of a material that is thermally deformed and disappears at or above a predetermined temperature.

[0019] The first electrode lead and the second electrode lead may be joined with a conductive adhesive outside the pouch outer casing.

[0020] The burst seal member may include a through hole through which the conductive adhesive can pass.

[0021] According to another aspect of the present invention, a battery module including the above-described pouch-type battery cell can be provided. [Effects of the Invention]

[0022] According to one aspect of the present invention, it is possible to provide a pouch-type battery cell that generates less heat and has excellent safety against thermal events under high-speed charging and high-power conditions, and a battery module including the same.

[0023] In addition, the present invention has various other effects, which will be described in each embodiment, or the description of effects that can be easily inferred by a person skilled in the art will be omitted. [Brief explanation of the drawings]

[0024] [Figure 1]FIG. 1 is a perspective view schematically illustrating a pouch-type battery cell according to the prior art. [Figure 2] FIG. 1 is a schematic cross-sectional view of a portion of a pouch-type battery cell according to the prior art. [Figure 3] 1 is a schematic perspective view of a pouch-type battery cell according to an embodiment of the present invention; [Figure 4] 1 is a diagram illustrating a joining structure of an electrode lead and an electrode tab according to an embodiment of the present invention; [Figure 5] FIG. 4 is a schematic partial cross-sectional view of the pouch-type battery cell of FIG. 3. [Figure 6] 4 is a partial cross-sectional view showing a change in state when the internal pressure of the pouch-type battery cell of FIG. 3 increases. FIG. [Figure 7] FIG. 10 is a partial cross-sectional view illustrating a pouch-type battery cell according to another embodiment of the present invention before its internal pressure increases. [Figure 8] FIG. 10 is a partial cross-sectional view illustrating a pouch-type battery cell according to another embodiment of the present invention after the internal pressure is increased. [Figure 9] FIG. 10 is a partial cross-sectional view illustrating a pouch-type battery cell according to yet another embodiment of the present invention before its internal pressure increases. [Figure 10] FIG. 10 is a partial cross-sectional view illustrating a pouch-type battery cell according to another embodiment of the present invention after the internal pressure is increased. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and claims should not be construed as being limited to their ordinary or dictionary meanings, but should be construed as meanings and concepts corresponding to the technical concept of the present invention, in accordance with the principle that the inventor himself can appropriately define the concept of terms in order to best explain the invention. Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiment of the present invention and do not represent the entire technical concept of the present invention, and therefore, various equivalents and modifications that can be substituted therefor may exist at the time of filing this application.

[0026] In the drawings, the size of each component or specific parts of the component may be exaggerated, omitted, or illustrated schematically for convenience and clarity of description. Therefore, the size of each component may not completely reflect the actual size. If a detailed description of well-known functions or configurations related to the present invention is deemed to unnecessarily obscure the gist of the present invention, such description will be omitted.

[0027] 3 to 5, a pouch-type battery cell 10 according to one embodiment of the present invention includes an electrode assembly 100, a pouch outer casing 200, an electrode tab bundle 300, an electrode lead 400, and a burst seal member 500.

[0028] The electrode assembly 100 is composed of a positive electrode plate 110, a negative electrode plate 130, and a separator 120, and is configured by stacking structures in which the positive electrode plate 110 and the negative electrode plate 130 are arranged to face each other with the separator 120 sandwiched between them.

[0029] That is, the electrode assembly 100 may have any structure in which the positive electrode plate 110 and the negative electrode plate 130 are repeatedly arranged with the separator 120 sandwiched therebetween, such as a stacked type in which the electrode plates and the separator 120 are sequentially stacked in the form of positive electrode plate 110 / separator 120 / negative electrode plate 130 / separator 120; a folded type in which the separator 120 is wound so that the separator 120 is located between the positive electrode plate 110 and the negative electrode plate 130; or a stacked-folded type that combines the stacked type and the folded type.

[0030] The positive electrode plate 110 may be formed by coating a positive electrode active material on an aluminum (Al) current collector plate, and the negative electrode plate 130 may be formed by coating a negative electrode active material on a copper (Cu) current collector plate. The positive electrode active material or the negative electrode active material may be formed by stirring a granular active material, a conductive additive, a binder, a plasticizer, etc. in a solvent.

[0031] The positive electrode plate 110 and the negative electrode plate 130 are configured in the form of plates and are spaced apart so that their plate surfaces face each other. The separator 120 is interposed between the positive electrode plate 110 and the negative electrode plate 130 to prevent direct contact between the positive electrode plate 110 and the negative electrode plate 130. The separator 120 has a porous structure to allow charge transfer between the positive electrode plate 110 and the negative electrode plate 130 during charging or discharging.

[0032] The pouch exterior material 200 has a multi-layer structure in which an outermost resin layer made of an insulating material such as PolyEthylene Terephthalate (PET) or Nylon is laminated, a metal layer made of an aluminum material that maintains mechanical strength and prevents the penetration of moisture and oxygen, and an inner resin layer made of a polyolefin-based material that has thermal adhesiveness and acts as a sealant.

[0033] The pouch exterior material 200 can be divided into a one-piece type in which one pouch sheet is folded to surround the electrode assembly 100, and a two-piece type in which two pouch sheets surround the electrode assembly 100. The one-piece pouch exterior material 200 is formed by forming a groove in a portion of a pouch sheet, accommodating the electrode assembly 100 in the groove, and folding the pouch sheet to cover the electrode assembly 100. Then, the edges of the overlapping pouch sheets, excluding the folded portion, are sealed by heat welding. As a result, the one-piece pouch exterior material 200 has a receiving portion 201 that accommodates the electrode assembly, and a sealing portion 202 in which three outer sides of the receiving portion 201 are sealed. Meanwhile, the two-piece pouch exterior material 200 includes two pouch sheets, i.e., an upper pouch sheet 210 and a lower pouch sheet 220. For example, a groove is formed in the lower pouch sheet 220 by molding, and the electrode assembly 100 is accommodated in the groove, and the upper pouch sheet 210 covers the electrode assembly 100. Then, the edges of the upper pouch sheet 210 and the lower pouch sheet 220 where they are overlapped are sealed by heat welding. As a result, the two-piece pouch exterior material 200 has a receiving portion 201 that accommodates the electrode assembly, and a sealing portion 202 in which all four sides of the outer periphery of the receiving portion 201 are sealed.

[0034] Therefore, a pouch-type battery cell 10 typically has a sealing portion 202 on the front and rear sides where the electrode leads 400 are located, and on at least one of the left and right sides in the width direction. In this case, the portion of the sealing portion 202 from which the electrode leads 400 protrude may be referred to as a cell terrace, and the other portion may be referred to as a side wing. For reference, the side wings of the pouch-type battery cell 10 are folded to reduce its volume.

[0035] The electrode tabs include a positive electrode tab provided in a region (non-coated portion) where the positive electrode plate 110 is not coated with the positive electrode active material, and a negative electrode tab provided in a region (non-coated portion) where the negative electrode plate 130 is not coated with the negative electrode active material. The electrode tabs may be plural, and electrode tabs of the same polarity may extend in the same direction from one side of the electrode assembly 100, and may be configured to have their ends bundled together to form an electrode tab bundle 300 and be connected to an electrode lead 400.

[0036] The electrode lead 400 can be configured to connect to the electrode tab bundle 300 , protrude to the outside of the pouch exterior material 200 , and function as an electrode terminal of the pouch-type battery cell 10 .

[0037] 4 and 5, an electrode lead 400 according to an embodiment of the present invention includes a first electrode lead 410 and a second electrode lead 420 that extend in the same direction facing each other and have the same polarity. A burst seal member 500 may be interposed between the first electrode lead 410 and the second electrode lead 420. The burst seal member 500 may be bonded to the first electrode lead 410 such that the first electrode lead 410 and the second electrode lead 420 are spaced apart, and the other surface (opposite surface) may be bonded to the second electrode lead 420.

[0038] According to this embodiment of the present invention, as will be described in detail later, the bottleneck phenomenon of charge / discharge current can be alleviated by separately joining and connecting electrode tabs to the electrode lead 400 composed of the first electrode lead 410 and the second electrode lead 420, thereby reducing heat generation and improving electrical safety under high-speed charging and high-power conditions. Furthermore, when a thermal event occurs, the internal pressure causes the rupture seal member 500 to rupture, thereby discharging gas between the first electrode lead 410 and the second electrode lead 420, thereby dispersing or relieving pressure and preventing explosion of the pouch-type battery cell 10.

[0039] Specifically, the pouch-type battery cell 10 according to an embodiment of the present invention may be configured with a pair of positive electrode leads 400 functioning as positive terminals and a pair of negative electrode leads 400 functioning as negative terminals, as shown in Fig. 3. Here, the pair of positive electrode leads 400 may further include a first electrode lead 410 and a second electrode lead 420, and the pair of negative electrode leads 400 may further include a first electrode lead 410 and a second electrode lead 420.

[0040] The pair of positive electrode leads 400 and the pair of negative electrode leads 400 are structurally almost identical. Therefore, in the following description, the first electrode lead 410 and the second electrode lead 420 may refer to the pair of positive electrode leads 400 or the pair of negative electrode leads 400. In addition, the electrode tabs include a positive electrode tab extending from the positive electrode plate 110 and a negative electrode tab extending from the negative electrode plate 130 in the electrode plate.

[0041] 5, the positive electrode tabs extend from each positive electrode plate 110 and are bundled at their ends to form a positive electrode tab bundle, which is joined to the positive electrode lead 400. Although not shown, the negative electrode tabs extend from each negative electrode plate 130 and are bundled at their ends to form a negative electrode tab bundle, which is joined to the negative electrode lead 400. For this reason, in the following description, the term "electrode tab" may refer to either a positive electrode tab or a negative electrode tab, and the term "electrode tab bundle 300" may refer to either a positive electrode tab bundle or a negative electrode tab bundle.

[0042] 4 and 5, in the pouch-type battery cell 10 of the present invention, the electrode tab bundle 300 is divided into two bundles. That is, the electrode tab bundle 300 includes a first electrode tab bundle 310 and a second electrode tab bundle 320. The first electrode tab bundle 310 is connected to a first electrode lead 410, and the second electrode tab bundle 320 is connected to a second electrode lead 420. In this case, the first electrode lead 410 and the second electrode lead 420 may be configured to be connected to the first electrode tab bundle 310 and the second electrode tab bundle 320, respectively, while being separated from each other at least inside the pouch exterior material 200 by a burst seal member 500.

[0043] In this way, the electrode tabs are divided into two groups and each group is joined and connected to a pair of electrode leads 400 of the same polarity, thereby alleviating the bottleneck phenomenon in current flow during charging and discharging of the pouch-type battery cell 10. Therefore, the pouch-type battery cell 10 according to the present invention generates significantly less heat under high-speed charging or high-power conditions than conventional pouch-type battery cells (see FIGS. 1 and 2).

[0044] 5, the pouch-type battery cell 10 according to the present invention may include a burst seal member 500 interposed between the first electrode lead 410 and the second electrode lead 420. The burst seal member 500 may be an adhesive resin composition. For example, the burst seal member 500 may be formed by curing an adhesive resin composition that has been applied in advance between the first electrode lead 410 and the second electrode lead 420.

[0045] The burst seal member 500 may serve to support the first electrode lead 410 and the second electrode lead 420 so as to space them apart from each other inside the pouch outer casing 200, and may also serve as a sealant to prevent electrolyte or the like from leaking into the gap between the first electrode lead 410 and the second electrode lead 420.

[0046] As described above, the pouch exterior material 200 has a heat-sealed sealing portion 202 at its edge. In the sealing portion 202, a lead film 600 may be used in the portion from which the electrode lead 400 protrudes in order to increase the bonding strength between the pouch exterior material 200 and the electrode lead 400.

[0047] The lead film 600 has a structure surrounding the outer periphery of the electrode lead 400 located in the sealing portion 202. The lead film 600 is bonded to the pouch exterior material 200 when the edge of the pouch exterior material 200 is heat-sealed, thereby providing a strong sealing force between the electrode lead 400 and the sealing portion 202.

[0048] In this embodiment, the lead film 600 includes a first lead film 610 bonded to the first electrode lead 410 and the upper pouch sheet 210 of the pouch exterior material 200, and a second lead film 620 bonded to the second electrode lead 420 and the lower pouch sheet 220 of the pouch exterior material 200, as shown in FIG.

[0049] Together with the first lead film 610 and the second lead film 620 , the burst seal member 500 seals the gap between the first electrode lead 410 and the second electrode lead 420 in the sealing portion 202 .

[0050] Furthermore, the burst seal member 500 according to an embodiment of the present invention may be made of a material having a weaker adhesive strength than the first lead film 610 or the second lead film 620 .

[0051] According to the configuration of the burst seal member 500, when gas is generated inside the pouch-type battery cell 10 due to a thermal event, the burst seal member 500 may burst or detach first when the internal pressure is lower than the limit pressure that the sealing portion 202 can withstand, thereby opening the gap between the first electrode lead 410 and the second electrode lead 420. Therefore, compared to the conventional pouch-type battery cell 10 having the structure shown in FIG. 2, gas and particles generated inside the battery cell may be discharged to the outside under lower pressure, preventing the pouch-type battery cell 10 from exploding.

[0052] 7 and 8 are partial cross-sectional views showing a pouch-type battery cell 10 according to another embodiment of the present invention before and after an increase in internal pressure, respectively.

[0053] Next, a pouch-type battery cell 10 according to another embodiment of the present invention will be described with reference to Figures 7 and 8. The same component numbers as those in the above-described embodiment indicate the same components, and redundant descriptions of the same components will be omitted, with the description focusing on differences from the above-described embodiment.

[0054] 7 and 8, in a pouch-type battery cell 10 according to another embodiment of the present invention, a burst seal member 500A may be configured to extend to the outside of the pouch exterior material 200 together with the first electrode lead 410 and the second electrode lead 420. That is, the burst seal member 500A may be configured to extend to the outside of the sealing portion 202. The first electrode lead 410 and the second electrode lead 420 may extend longer than the burst seal member 500A. The first electrode lead 410 and the second electrode lead 420 may be used individually as electrode terminals, or may be stacked so as to be in contact with each other and function as a single electrode terminal, as shown in FIG.

[0055] In particular, the rupture seal member 500A of this embodiment may be made of a material that thermally deforms and disappears above a predetermined temperature. In this case, when a thermal event occurs inside the pouch-type battery cell 10 and heat and pressure act on the rupture seal member 500A, the rupture seal member 500A melts and disappears. This increases the gap between the first electrode lead 410 and the second electrode lead 420 inside the pouch exterior material 200, and the portion of the rupture seal member 500A exposed outside the sealing portion 202 together with the first electrode lead 410 and the second electrode lead 420 disappears, as shown in FIG. 8, forming a vent space outside the sealing portion 202. This allows gas, particles, etc. to be discharged from the vent space to the outside of the pouch exterior material 200 (in the Y-axis direction intersecting the X-axis and Z-axis in FIG. 8).

[0056] For example, in a situation where the tip ends of the first electrode lead 410 and the second electrode lead 420 are strongly bonded and cannot be opened, or where the tip ends of the first electrode lead 410 and the second electrode lead 420 are welded together to a conductor such as a bus bar (not shown), in this embodiment, as described above, a vent space VS is secured and the internal pressure of the pouch-type battery cell 10 is released.

[0057] 9 and 10 are partial cross-sectional views showing a pouch-type battery cell 10 according to yet another embodiment of the present invention before and after the internal pressure is increased, respectively.

[0058] In comparison with the above-described embodiment, in a pouch-type battery cell 10 according to yet another embodiment of the present invention, the burst seal member 500B is configured to extend outside the sealing portion 202 and may extend substantially coextensively with the first electrode lead 410 and the second electrode lead 420.

[0059] Furthermore, the first electrode lead 410 and the second electrode lead 420 exposed to the outside of the pouch outer casing 200 may be configured to be electrically conductive to each other even if a rupture seal member 500B is present between them. For example, as shown in Fig. 9, the first electrode lead 410 and the second electrode lead 420 may be joined with a conductive adhesive J1 outside the pouch outer casing 200. Here, the conductive adhesive J1 may be, for example, silver nano ink.

[0060] In addition, the rupture seal member 500B may include a hole for filling with the conductive adhesive J1. That is, by filling the hole with the conductive adhesive J1, the first electrode lead 410 and the second electrode lead 420 may be configured to be fixed to each other and to be electrically connected.

[0061] Therefore, according to this embodiment, a pair of electrode leads 400 of the same polarity can be used as a single electrode lead 400. Furthermore, when a thermal event occurs inside the pouch-type battery cell 10 and heat and pressure act on the rupture seal member 500B, the rupture seal member 500B melts or its bonding strength weakens, causing a greater gap between the first electrode lead 410 and the second electrode lead 420 inside the pouch exterior material 200. As shown in FIG. 10 , the portion of the rupture seal member 500B exposed outside the sealing portion 202 together with the first electrode lead 410 and the second electrode lead 420 is opened, forming a vent space VS outside the sealing portion 202. Therefore, gas, particles, etc. can be discharged from the vent space VS to the outside of the pouch exterior material 200 (in FIG. 10 , in the Y-axis direction intersecting the X-axis and Z-axis).

[0062] Meanwhile, a battery module according to the present invention may include the above-described pouch-type battery cells 10, a bus bar frame assembly for electrically connecting the pouch-type battery cells 10, and a module case having an internal space for accommodating the pouch-type battery cells 10. The battery module may also include a vent hole on at least one side of the module case for discharging gas emitted from the pouch-type battery cells 10 to the outside of the module case. The battery module may include a module case for accommodating the pouch-type battery cells 10.

[0063] At least one battery module according to the present invention can be applied to a battery pack. That is, a battery pack according to the present invention can include one or more battery modules. Furthermore, the battery pack according to the present invention can be applied to automobiles such as electric vehicles. That is, a vehicle according to the present invention can include at least one battery pack according to the present invention.

[0064] Although terms indicating directions such as up, down, left, right, front, and back are used in this specification, it will be obvious to those skilled in the art that these terms indicate relative positions and are used only for convenience of explanation, and may vary depending on the position of the object in question, the position of the observer, etc.

[0065] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and it is of course possible for a person having ordinary skill in the art to which the present invention pertains to make various modifications and variations within the scope of the technical spirit of the present invention and the equivalent scope of the claims. [Explanation of symbols]

[0066] 1. Pouch-type secondary battery 10 pouch-type battery cells 100 electrode assembly 110 Positive electrode plate 120 Separation membrane 130 Negative electrode plate 200 pouch outer packaging material 201 Storage section 202 Sealing part 210 Upper pouch sheet 220 Lower pouch sheet 300 electrode tab bundles 310 first electrode tab bundle 320 second electrode tab bundle 400 Electrode Leads (Negative Electrode Lead; Positive Electrode Lead) 410 First electrode lead 420 Second electrode lead 500 Rupture sealing material 500A rupture sealing material 500B Rupture sealing material 600 lead film 610 First Lead Film 620 Second Lead Film

Claims

1. an electrode assembly in which positive and negative electrode plates are repeatedly arranged to face each other with a separator between them; a pouch outer casing for hermetically housing the electrode assembly; an electrode lead connected to an electrode tab bundle extending from the electrode assembly inside the pouch exterior material and protruding to an outside of the pouch exterior material, the electrode leads include a first electrode lead and a second electrode lead that extend in the same direction while facing each other and have the same polarity; a burst seal member disposed between the first electrode lead and the second electrode lead such that one surface of the burst seal member is bonded to the first electrode lead and the other surface of the burst seal member is bonded to the second electrode lead.

2. the electrode tab bundle is divided into two bundles, including a first electrode tab bundle and a second electrode tab bundle; The pouch-type battery cell according to claim 1 , wherein the first electrode tab bundle is connected to the first electrode lead, and the second electrode tab bundle is connected to the second electrode lead.

3. The pouch-type battery cell according to claim 1 , wherein the first electrode lead and the second electrode lead are separated from each other inside the pouch exterior material.

4. the pouch exterior material includes a sealing portion whose peripheral edge is sealed, 2. The pouch-type battery cell according to claim 1, wherein the sealing portion includes a first lead film that joins the first electrode lead and the pouch exterior material, and a second lead film that joins the second electrode lead and the pouch exterior material.

5. The pouch-type battery cell according to claim 4 , wherein the adhesive strength of the burst seal member is weaker than the adhesive strength of the first lead film or the second lead film.

6. 5. The pouch-type battery cell according to claim 4, wherein the burst seal member extends to the outside of the pouch exterior together with the first electrode lead and the second electrode lead.

7. 7. The pouch-type battery cell according to claim 6, wherein the burst seal member is made of a material that is thermally deformed and disappears at a predetermined temperature or higher.

8. The pouch-type battery cell according to claim 6 , wherein the first electrode lead and the second electrode lead are bonded to each other outside the pouch exterior material with a conductive adhesive.

9. The pouch-type battery cell according to claim 8 , wherein the burst seal member includes a through-hole through which the conductive adhesive can pass.

10. A battery module comprising the pouch-type battery cell according to any one of claims 1 to 9.

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