Disconnection prevention battery module

Abstract

The present invention provides a pouch-type battery cell structure including an electrode lead extending from one longitudinal end, the battery cell structure including margin portions that are deformed when both ends of the electrode lead are pulled, thereby extending the electrode lead, and a battery module structure that incorporates a battery cell stack formed by stacking a plurality of battery cells, including at least one of the above-mentioned battery cells, on top of each other.

Description

[Technical Field]

[0001] This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0120659, filed on September 23, 2022, and all contents disclosed in the documents of this Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a battery module that prevents breakage or damage to electrode leads. Specifically, the present invention relates to a battery module formed by stacking multiple pouch-type battery cells, in which breakage or damage to electrode leads due to swelling is prevented and welding strength to bus bars is ensured. [Background technology]

[0003] Secondary batteries, which are easily applicable to a wide range of products and have electrical properties such as high energy density, are commonly used not only in portable devices but also in electric vehicles or hybrid vehicles powered by electrical sources, power storage devices, etc. These secondary batteries are attracting attention as a new energy source because they not only have the primary advantage of dramatically reducing the use of fossil fuels, but also because they are environmentally friendly and improve energy efficiency by not producing any by-products from energy use.

[0004] While small mobile devices use one to 23 battery cells per device, medium to large devices such as automobiles require high output and large capacity, so medium to large battery modules, which electrically connect multiple battery cells, are used.

[0005] It is desirable to manufacture medium- to large-sized battery modules with small size and weight if possible, so prismatic batteries and pouch-shaped batteries, which can be stacked with high density and have low weight relative to capacity, are mainly used as battery cells for medium- to large-sized battery modules.

[0006] FIG. 1 is a perspective view showing a pouch-type battery cell. Referring to FIG. 1, the battery cell 1 may include an electrode assembly (not shown), a pouch 11 that houses the electrode assembly, is folded in half, and is fusion-sealed with a first seal portion 111a provided on both sides in the length direction (X) and a second seal portion 111b provided on one side in the width direction (Z), and a pair of electrode leads 12 that extend from the electrode assembly to both sides in the length direction and protrude outside the pouch 11. The electrode leads 12 may be fusion-sealed to the pouch 11 via a lead film 121 provided at a position corresponding to the first seal portion 111a. A plurality of the battery cells 1 described above may be stacked to form a high-capacity and / or high-voltage battery module.

[0007] 2 and 3 are a perspective view and an exploded perspective view, respectively, of a battery module. Referring to these figures, the battery module 2 may include a battery cell stack 21 formed by stacking a plurality of the battery cells 1, bus bar frames 211 located on both longitudinal sides of the battery cell stack 21, and a housing 22 that accommodates the battery cell stack 21 and the bus bar frame 211. The housing 22 may include a U-frame 221 that is open at the top and front and rear, a top plate 222 that covers the top of the U-frame 221, and a pair of end plates 223 that cover the front and rear of the U-frame 221, respectively. The electrode leads 12 may be connected to each other in series or parallel by being welded to bus bars 213 provided on the bus bar frame 211.

[0008] 4 is an enlarged cross-sectional view showing how an electrode lead in a battery module is welded to a bus bar. Referring to FIG. 4, the bus bar frame 211 may be provided with a slit 212 through which the electrode lead 12 can pass. The electrode lead 12 may extend from the electrode assembly 13, protrude outside the pouch 11, pass through the slit 212, and be welded to the bus bar 213 provided on the outer surface of the bus bar frame 211 in the longitudinal direction. In this case, the electrode lead 12 may be bent at a first bent portion 123a located on the first sealing portion 111a side and a second bent portion 123b located on the bus bar 213 side so that an end of the electrode lead 12 contacts the bus bar 213.

[0009] Meanwhile, it is widely known that the battery cells 1 may experience swelling, a phenomenon in which gas is generated inside the pouch 11, causing the pouch 11 to expand. When swelling occurs, the battery cells 1 expand while pushing against each other in the stacking direction (Y). This displacement of the battery cells 1 may cause the welding between the electrode leads 12 and the bus bars 213 to be released, resulting in disconnection or damage to a portion of the electrode leads 12. In particular, the first bent portion 123a is more susceptible to damage because the degree of bending exceeds the designed extent due to the battery cells 1 being pushed outward. Therefore, a battery cell and battery module structure is needed that prevents disconnection between the electrode leads 12 and the bus bars 213 despite the above-described displacement of the battery cells 1.

[0010] 4, during the bending of the electrode lead 12 at each bending portion 123, a springback phenomenon may occur in which the electrode lead 12 elastically recovers to a certain angle without undergoing any plastic deformation. The degree of bending of the electrode lead 12 at each bending portion 123 is a very important factor in determining the springback phenomenon. This is because the greater the degree to which the electrode lead 12 is bent at each bending portion 123, the greater the rate of plastic deformation and the less the springback phenomenon occurs. The springback phenomenon affects the weld strength between the electrode lead 12 and the bus bar 213 and the strength of the electrode lead 12 itself. Therefore, in order to be able to design these strengths, the degree of springback must be predictable and adjustable as needed. Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention was made in light of the background of the conventional technology described above, and has an object to provide a battery cell and battery module structure that prevents disconnection between electrode leads and bus bars and damage to electrode leads despite displacement of the battery cell due to swelling.

[0012] Yet another technical object of the present invention is to provide a battery cell and battery module structure in which the degree of springback can be adjusted in the process of bending the electrode leads for welding to the bus bars, thereby enabling the strength of the electrode leads and the welding strength between the electrode leads and the bus bars to be designed.

[0013] The technical object of the present invention is not limited to the above-mentioned objects, and other unmentioned objects and advantages of the present invention can be understood from the following description and can be more clearly understood from the embodiments of the present invention. Furthermore, it can be easily understood that the objects and advantages of the present invention can be achieved by the means and combinations thereof set forth in the claims. [Means for solving the problem]

[0014] In order to solve the above problems, the present invention provides a pouch-type battery cell structure including electrode leads extending from one longitudinal end, the battery cell structure including margin portions that can be deformed by pulling both ends of the electrode leads, thereby allowing the electrode leads to be stretched.

[0015] The predetermined sections on both sides of the margin may be placed on the same imaginary plane, i.e., there may be one imaginary plane that simultaneously passes through the predetermined sections on both sides of the margin.

[0016] The predetermined section may be a section of 1 mm or more on each side of the margin.

[0017] The margin portion may be formed in an arch shape having an arc-shaped longitudinal cross section with a constant radius of curvature. For example, the margin portion may be formed in an arch shape having a semicircular longitudinal cross section with a constant radius of curvature.

[0018] The margin portion can be manufactured by plastically deforming the electrode lead using a die having a shape corresponding to the margin portion, or by bending the electrode lead.

[0019] The present invention also provides a battery module structure incorporating a battery cell stack formed by stacking a plurality of battery cells, including at least one of the battery cells described above, on top of one another.

[0020] The battery cell stack may include a section in which the electrode leads are longer as the battery cells are located more outward in the thickness direction. That is, in a section along the thickness direction of the battery cell stack, the electrode leads of the battery cells located relatively outward in the thickness direction may be longer than the electrode leads of the battery cells located relatively inward in the thickness direction.

[0021] Alternatively, the battery cell stack may include a section in which the more outer the battery cells are located in the thickness direction, the greater the number of margin portions provided on the electrode leads. That is, in a section along the thickness direction of the battery cell stack, the electrode leads of the battery cells located relatively outer in the thickness direction may have a greater number of margin portions than the electrode leads of the battery cells located relatively inner in the thickness direction.

[0022] The battery cell stack may be formed symmetrically on both sides of its center in the thickness direction, i.e., the battery cell stack may be formed so that its normal direction is the thickness direction and its plane of symmetry is a plane passing through its center.

[0023] The present invention also provides a battery pack including the battery module, and a vehicle including the battery pack. The structures of the battery pack and the vehicle are already known, and therefore will not be described further in this specification. [Effects of the Invention]

[0024] The present invention can provide a battery cell and battery module structure that includes a margin portion that deforms when displacement occurs in the battery cell and stretches the electrode lead, thereby preventing disconnection or damage to the electrode lead when swelling occurs.

[0025] The present invention also provides a battery cell and battery module structure in which the electrode leads have margin portions but have a shape that allows them to be bent in the same way as when they are planar, making it possible to design the degree to which the springback phenomenon occurs.

[0026] Yet another advantage of the present invention is that it provides a battery cell and battery module structure that, despite including electrode leads with margins, can be manufactured using the same manufacturing processes and equipment as in the case of a battery cell or battery module that does not have the margins.

[0027] In addition to the above, the present invention can achieve various other effects, which will be explained in each embodiment, or explanations of effects that can be easily inferred by ordinary engineers will be omitted. [Brief explanation of the drawings]

[0028] [Figure 1] FIG. 1 is a perspective view showing a pouch-type battery cell. [Figure 2] FIG. 2 is a perspective view showing a battery module. [Figure 3] FIG. 2 is an exploded perspective view showing a battery module. [Figure 4] FIG. 4 is an enlarged cross-sectional view showing how electrode leads in a battery module are welded to bus bars. [Figure 5] 1 is a perspective view showing a battery cell according to an embodiment of the present invention; [Figure 6] 1 is a cross-sectional view showing a battery cell according to an embodiment of the present invention. [Figure 7] 1 is a cross-sectional view showing a battery cell according to an embodiment of the present invention. [Figure 8] 1A to 1C are schematic diagrams illustrating a manufacturing process of a battery cell according to an embodiment of the present invention. [Figure 9] 1A to 1C are schematic diagrams illustrating a manufacturing process of a battery cell according to an embodiment of the present invention. [Figure 10] 4 is an enlarged cross-sectional view showing how electrode leads are welded to bus bars in a battery module according to an embodiment of the present invention. FIG. [Figure 11] 4 is an enlarged cross-sectional view showing swelling occurring in a battery module according to an embodiment of the present invention; FIG. [Figure 12] 1 is a perspective view showing a battery pack including a battery module according to the present invention; [Figure 13] 1 is a perspective view of a vehicle including a battery pack according to the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0029] The above-mentioned objects, features, and advantages will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can easily implement the technical concept of the present invention. In describing the present invention, if a detailed description of known technologies relating to the present invention is deemed to obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings are used to indicate the same or similar components.

[0030] Although terms such as "first" and "second" are used to indicate various components, it is understood that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless otherwise specified, the first component may also be the second component.

[0031] Throughout the specification, unless otherwise specified, each element may be singular or plural.

[0032] Hereinafter, when an arbitrary structure is arranged "on top (or bottom)" of a component or "above (or below)" a component, it means that the arbitrary structure is not only arranged in contact with the upper surface (or lower surface) of the component, but also that other structures may be interposed between the component and the arbitrary structure arranged above (or below) the component.

[0033] Furthermore, when a component is described as being "coupled," "coupled," or "connected" to another component, it should be understood that the components may be directly coupled or connected to each other, but that other components may be "intervening" between the components, or that each component may be "coupled," "coupled," or "connected" via other components.

[0034] As used herein, singular expressions include plural expressions unless the context clearly dictates otherwise. Terms such as "comprise" or "include" in this application should not be interpreted as including all of the components or steps described in the specification, but should be interpreted as meaning that some of the components or steps may not be included, or that additional components or steps may be included.

[0035] In the entire specification, "A and / or B" means A, B or A and B unless otherwise specified, and "C to D" means C or more and D or less unless otherwise specified.

[0036] The present invention provides a pouch-type battery cell including electrode leads extending from one longitudinal end, the battery cell including margin portions that can be deformed by pulling both ends of the electrode leads, thereby allowing the electrode leads to be extended. Preferred embodiments of the battery cell according to the present invention will now be described with reference to the accompanying drawings.

[0037] 5, 6, and 7 are perspective and cross-sectional views, respectively, of a battery cell according to one embodiment of the present invention. Referring to these figures, the battery cell 1 may include an electrode assembly 13, a pouch 11, and electrode leads.

[0038] The electrode assembly 13 may be formed by stacking a plurality of positive electrodes and negative electrodes alternately with a separator interposed therebetween.

[0039] The pouch 11 may be made from a metal foil material.

[0040] The inner and / or outer surfaces of the pouch 11 may be coated with a synthetic resin layer for insulation.

[0041] The pouch 11 can accommodate the electrode assembly 13 and be folded in half, and can be sealed with first sealed portions 111a on both sides in the length direction (X) and with a second sealed portion 111b on one side in the width direction (Z). The sealing can be achieved by fusing a synthetic resin layer coated on the inner surface of the pouch 11. In particular, the second sealed portion 111b can be resealed by paulding and / or tape application after being fusion-sealed.

[0042] The electrode lead 12 can be formed from a flat metal foil material having a length and a width.

[0043] A plurality of electrode leads 12 may be provided, and preferably, a pair of electrode leads 12 may be provided.

[0044] The electrode lead 12 may extend from the electrode assembly 13. Specifically, the electrode lead 12 may extend from the positive electrode or the negative electrode of the electrode assembly 13. Alternatively, the electrode lead 12 may be electrically connected to the positive electrode or the negative electrode by being connected to an electrode tab extending from the positive electrode or the negative electrode. In this case, the electrode tabs may extend from a plurality of the positive electrodes or the negative electrodes, respectively, and be connected to the electrode lead 12 in a stacked state.

[0045] The electrode lead 12 may extend from the electrode assembly 13 and protrude outside the pouch 11. For example, the electrode lead 12 may protrude outside the pouch 11 through the first seal portion 111a. In this case, a lead film made of a synthetic resin material may be provided at a portion of the electrode lead 12 that overlaps with the first seal portion 111a, and the electrode lead 12 may be fused to the pouch 11 located on both sides of the first seal portion 111a in the thickness direction.

[0046] The electrode lead 12 may be provided with a margin portion 122. The margin portion 122 may be provided on a part of the portion of the electrode lead 12 that protrudes outside the pouch 11.

[0047] The margin portion 122 may be a section that is not a straight line between the start point and the end point on the cross section of the electrode lead 12. In other words, the margin portion 122 may be a section on the electrode lead 12 that is not aligned with the direction in which the electrode lead 12 extends. As a result, since the start point and the end point of the margin portion 122 are not connected by the shortest distance, both ends of the electrode lead 12 are pulled toward each other, thereby deforming the shape of the electrode lead 12 and approaching a straight line, and the electrode lead 12 can be stretched overall along the direction in which it extends.

[0048] Predetermined sections on both sides of the margin portion 122, i.e., both sections extending a predetermined length outward from the start point and end point of the margin portion 122 along the direction in which the electrode lead 12 extends, may be formed to be located on the same imaginary plane 122P. That is, in this case, the predetermined sections may be located on a single straight line in a cross-sectional view of the electrode lead 12. In other words, the electrode lead 12 may extend in the same direction in at least a predetermined section with the margin portion 122 in front and behind it, and the straight line connecting the start point and end point of the margin portion 122 may also be along the direction in which the electrode lead 12 extends.

[0049] The predetermined section can be set in various ways depending on the physical properties of the electrode lead 12 and the design of the battery module 2, which will be described later. For example, the predetermined section may be a section of 1 mm or more on both sides of the margin portion 122. Alternatively, the predetermined section may be set to be smaller than this.

[0050] The margin portion 122 may be formed in various shapes. For example, the margin portion 122 may be formed to have a plurality of acute or obtuse angled portions as shown in Fig. 6. Alternatively, the margin portion 122 may be formed in an arch shape having an arc-shaped longitudinal cross section with a constant radius of curvature (R) as shown in Fig. 7. In particular, the margin portion 122 may be formed in an arch shape having a semicircular longitudinal cross section with a constant radius of curvature (R).

[0051] 8 and 9 are schematic diagrams illustrating a manufacturing process of a battery cell according to an embodiment of the present invention. Referring to these drawings, the margin portion 122 can be formed by pressing the electrode lead 12 with a die having a shape corresponding to the margin portion 122 and plastically deforming the electrode lead 12. Alternatively, the margin portion 122 can be formed by bending the electrode lead 12.

[0052] The present invention also provides a battery module structure incorporating a battery cell stack formed by stacking a plurality of battery cells, including at least one of the battery cells. Hereinafter, preferred embodiments of the battery module according to the present invention will be described with reference to the accompanying drawings.

[0053] 2 and 3 are a perspective view and an exploded perspective view, respectively, of a battery module 2. Referring to these figures, the battery module 2 may include a battery cell stack 21, a bus bar frame 211, and a housing 22.

[0054] The battery cell stack 21 may be formed by stacking a plurality of battery cells, including at least one of the battery cells 1, along the thickness direction.

[0055] The bus bar frames 211 may be located on both side surfaces of the battery cell stack 21 in the longitudinal direction.

[0056] The battery cell stack 21 and the bus bar frame 211 can be housed inside the housing 22.

[0057] The housing 22 may include a U-frame 221 that is open at the top and at the front and rear, a top plate 222 that covers the top of the U-frame 221, and a pair of end plates 223 that cover the front and rear of the U-frame 221. However, the housing 22 may have any shape as long as it covers the battery cell stack 21 and the bus bar frame 211 on six sides.

[0058] The bus bar frame 211 may be provided with a bus bar 213 .

[0059] The electrode leads 12 can be connected to each other in series or parallel by being welded to a bus bar 213 provided on the bus bar frame 211 .

[0060] 10 is an enlarged cross-sectional view illustrating a state in which an electrode lead is welded to a bus bar in a battery module according to an embodiment of the present invention. Referring to this figure, the bus bar frame 211 may be provided with a slit 212 that passes through the bus bar frame 211 in the longitudinal direction.

[0061] The bus bars 213 may be installed on one or both sides of the slits 212 on the longitudinal side surfaces of the bus bar frame 211. In this case, the side ends of the bus bars 213 may protrude from, be flush with, or be recessed to form a step with the side ends of the slits 212.

[0062] The electrode lead 12 may extend from the electrode assembly 13, protrude outside the pouch 11 through the first seal portion 111a, pass through the slit 212, and be welded to the bus bar 213.

[0063] The electrode lead 12 may be bent at a bent portion 123 so that the end portion thereof approaches the bus bar 213 .

[0064] There may be a plurality of bending portions 123. For example, the bending portion 123 may include a first bending portion 123a provided at a position where the first seal portion 111a starts or ends, and a second bending portion 123b provided at a position where the first seal portion 111a starts or ends, and a second bending portion 123b provided at a position where the slit 212 or the bus bar 213 ends.

[0065] During the process of bending the electrode lead 12 at each bending portion 123, a springback phenomenon may occur in which the electrode lead 12 does not undergo any plastic deformation but elastically restores itself by a certain angle. The degree of bending of the electrode lead 12 at each bending portion 123 is a very important factor in determining the springback phenomenon. This is because the greater the degree to which the electrode lead 12 is bent at each bending portion 123, the greater the rate of plastic deformation and the less the springback phenomenon occurs. The springback phenomenon has a significant effect on the weld strength between the electrode lead 12 and the bus bar 213 and the strength of the electrode lead 12 itself.

[0066] When predetermined sections on both sides of the margin portion 122 are on the same imaginary plane 122P, the degree of bending of the electrode lead 12 at the bending portion 123 is the same as when the electrode lead 12 is planar and does not have the margin portion 122. That is, with the margin portion 122 at the front and back, the same angle as when the electrode lead 12 does not have the margin portion 122 can be formed, and the degree of springback can also be the same as when the margin portion 122 is not provided.

[0067] The advantage of these methods is that the present invention can be implemented without reducing strength due to the springback phenomenon by simply including battery cells that include the margin portion in the battery module while maintaining the manufacturing processes and equipment for the existing battery module that includes only battery cells that do not have the margin portion.

[0068] The predetermined section can be determined in various ways depending on physical properties such as the radius of bending at the bending portion 123 or the thickness of the electrode lead 12. For example, the stronger the elasticity of the electrode lead 12, the larger the radius of bending at the bending portion 123. In this case, the predetermined section needs to be long enough so that deformation at the bending portion 123 does not affect the margin portion 122. In the case of a typical electrode lead, if the predetermined section is 1 mm or more, the same results as when the margin portion 122 is not provided can be obtained.

[0069] Meanwhile, the battery cell 1 may generate gas inside the pouch 11, causing the pouch 11 to swell up, resulting in a swelling phenomenon.

[0070] 11 is an enlarged cross-sectional view illustrating swelling in a battery module according to an embodiment of the present invention. When swelling occurs in the battery cell 1, the thickness of the battery cell stack 21 increases, which may cause deformation of the sidewall of the U-frame 221. The battery cells 1 expand in the thickness direction and push against each other, which may cause displacement of the battery cells 1 and the first bent portion 123a. This displacement may be greater the closer the battery cells 1 are to the outer side of the battery cell stack 21 in the thickness direction. As a result of this displacement, a tensile load is applied to the electrode lead 12, which increases the degree of bending of the first bent portion 123a. This increases the risk of damage or breakage of the welded portion between the electrode lead 12 and the bus bar 213 or the first bent portion 123a.

[0071] According to the present invention, when the electrode lead 12 having the margin portion 122 receives a tensile load due to the displacement caused by the swelling, the margin portion 122 deforms to a nearly linear shape, so that the overall length of the electrode lead 12 can be further extended. This reduces the load applied to the first bent portion 123a and the welded portion between the electrode lead 12 and the bus bar 213, thereby preventing breakage or disconnection.

[0072] As described above, the displacement due to swelling may be greater the further the battery cell 1 is located in the thickness direction of the battery cell stack 21. Therefore, the battery cell stack 21 may include a section in which the length of the electrode lead 12, including the margin portion 122, is longer the further the battery cell 1 is located in the thickness direction of the stack 21. For example, the three battery cells 1 located at the outermost periphery of the battery cell stack 21 may be formed such that the length of the electrode lead 12, including the margin portion 122, gradually increases toward the outside in the thickness direction. As a result, the greater the displacement of the battery cell 1 and the stronger the tensile load applied to the electrode lead 12, the greater the elongation limit of the electrode lead 12, and the more effectively the risk of damage or disconnection of the electrode lead 12 can be prevented.

[0073] Referring further to FIG. 7, a longer length of the electrode lead 12 including the margin portion 122 means that the radius of curvature (R) is larger in the margin portion 122, which has a semicircular cross section with a constant radius of curvature (R).

[0074] Alternatively, the battery cell stack 21 may include a section in which the number of margin portions 122 provided on the electrode leads 12 increases as the battery cells 1 are positioned further outward in the thickness direction of the battery cell stack 21. Therefore, the greater the displacement of the battery cells 1 and the stronger the tensile load applied to the electrode leads 12, the more frequently the electrode leads 12 will elongate, thereby more effectively preventing the risk of damage or disconnection of the electrode leads 12.

[0075] Because the difference in displacement between the battery cells 1 due to swelling does not distinguish between the left and right sides, the battery cell stack 21 can be formed in a shape that is symmetrical on both sides of its center in the thickness direction. That is, the battery cell stack can be formed so that its normal direction is the thickness direction and that a plane passing through its center is its plane of symmetry. Alternatively, the battery cell stack 21 can be formed in a shape that is symmetrical on both sides of its center in the thickness direction, at least with respect to the margin portion 122.

[0076] 12 and 13 are perspective views showing a battery pack including a battery module according to the present invention and a vehicle including the same, respectively. Referring to these figures, the present invention can provide a battery pack (P) including the battery module 2 and a vehicle (V) including the battery pack (P). The structures of the battery pack (P) and the vehicle (V) are already known, and will not be described further in this specification.

[0077] It should be understood that the above-described embodiments are illustrative in all respects and are not limiting, and the scope of the present invention is defined by the following claims rather than the above detailed description. All modifications and variations within the meaning and scope of the following claims, as well as equivalent concepts, should be construed as being included within the scope of the present invention.

[0078] Although the present invention has been described above with reference to exemplary drawings, the present invention is not limited to the embodiments and drawings disclosed in this specification, and various modifications may be made by those skilled in the art within the scope of the technical concept of the present invention. Furthermore, even if the effects of the configuration of the present invention are not explicitly described in the above description of the embodiments of the present invention, it is natural that the effects that can be predicted by the configuration should also be recognized. [Explanation of symbols]

[0079] 1 battery cell 11 pouches 111 Seal part 111a First seal part 111b Second seal part 12 electrode leads 121 Lead Film 122 Margin 122P Virtual Plane R radius of curvature 123 Bend section 123a 1st bend 123b 2nd bend 13 Electrode assembly 2 Battery Module 21 Battery cell stack 211 Busbar Frame 212 Slit 213 Busbar 22 Housing 221 U-frame 222 Top Plate 223 End Plate P Battery pack V Automobile X Length direction / Front-to-back direction Y Thickness direction / left / right direction / layer direction Z width direction / vertical direction / height direction

Claims

1. a battery cell stack including a plurality of pouch-shaped battery cells stacked together, each of the pouch-shaped battery cells including an electrode lead extending from one end in the length direction; a bus bar frame provided at an end of the battery cell stack in a longitudinal direction, the bus bar frame including a bus bar to which the electrode lead is connected, At least one of the battery cells The electrode lead includes margin portions that are deformed by being pulled at both ends thereof and extend the electrode lead, The predetermined sections on both sides of the margin portion are arranged on substantially the same imaginary plane. Battery module.

2. The electrode lead is a first bent portion bent on an opposite side of the bus bar with respect to the margin portion; a second bent portion bent on the bus bar side with respect to the margin portion, The battery module according to claim 1 .

3. The predetermined section is a section of 1 mm or more on each side of the margin portion. The battery module according to claim 1 .

4. The margin portion is formed in an arch shape having an arc-shaped longitudinal section with a constant radius of curvature. The battery module according to claim 1 .

5. The margin portion is formed in an arch shape having a semicircular vertical cross section with a constant radius of curvature. The battery module according to claim 4 .

6. the margin portion is manufactured by plastically deforming the electrode lead using a die having a shape corresponding to the margin portion; The battery module according to claim 1 .

7. The margin portion is manufactured by bending the electrode lead. The battery module according to claim 1 .

8. the battery cell stack includes a section in which the elongation limit of the margin portion becomes larger as the battery cells move toward the outer side in a thickness direction of the battery cell stack, The battery module according to claim 1 .

9. The margin portion is formed in an arch shape having an arc-shaped longitudinal section with a constant radius of curvature, the battery cell stack includes a section in which the radius of curvature of the margin portion provided on the electrode lead increases toward the outer side of the battery cell in a thickness direction of the battery cell stack, The battery module according to claim 8 .

10. the battery cell stack includes a section in which the number of the margin portions provided on the electrode leads increases as the battery cells move toward the outer side in a thickness direction of the battery cell stack. The battery module according to claim 8 .

11. The battery cell stack is formed symmetrically on both sides of the center in the thickness direction. The battery module according to claim 8 .

12. A battery module comprising the battery module according to any one of claims 1 to 11. Battery pack.

13. A battery pack comprising the battery pack of claim 12. car.

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