Battery pack

Abstract

A battery pack is disclosed. The battery pack includes a battery cell stack in which a plurality of battery cells are stacked, and battery cell junctions are disposed between the battery cells. Each of the battery cell joining portions includes a first adhesive tape disposed to correspond to an edge of a surface of one of the battery cells and a second adhesive tape disposed to correspond to a center portion of the surface of the one of the battery cells. The first tape and the second tape form a single layer and are spaced apart from each other.

Description

[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2024-0030906, filed on March 4, 2024, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0002] One or more embodiments relate to a battery pack. Background Art

[0003] Generally, unlike primary batteries, which are not rechargeable, secondary batteries are rechargeable and dischargeable. They are used as energy sources for mobile devices, electric vehicles, hybrid vehicles, electric bicycles, and uninterruptible power supplies. Depending on the type of external device they are used in, secondary batteries can be used as individual cells or in modules where cells are connected and bundled into a single unit.

[0004] Small mobile devices, such as mobile phones, can operate for a limited period using the output of a single battery. However, when long-term operation or high-power operation is required (such as in electric or hybrid vehicles that consume large amounts of electricity), modules with multiple batteries are preferred due to output and capacity issues. The output voltage and current can be increased with the number of internal batteries. Summary of the Invention

[0005] One or more embodiments include a battery pack including a plurality of battery cells, which is reliable even if dropped because expansion spaces are provided between the plurality of battery cells.

[0006] However, the technical problems to be solved by the present disclosure are not limited to the above problems, and other problems not mentioned can be clearly understood by those skilled in the art through the description herein.

[0007] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments of the disclosure.

[0008] According to one or more embodiments, a battery pack includes a battery cell stack in which a plurality of battery cells are stacked and battery cell joints arranged between the battery cells, wherein each of the battery cell joints includes a first tape and a second tape, the first tape being arranged to correspond to an edge of a surface of one of the battery cells, the second tape being arranged to correspond to a center portion of a surface of one of the battery cells, and wherein the first tape and the second tape form a single layer and are spaced apart from each other.

[0009] The first tape may be harder than the second tape.

[0010] The second tape may be compressible.

[0011] The second tape may include a sponge.

[0012] The first tape may include rubber.

[0013] The first tape may surround the second tape.

[0014] The first tape and the second tape may be spaced apart from each other by a second gap.

[0015] The second gap may be about 1 mm or greater.

[0016] The first tape may have a first gap cut on one side.

[0017] The first adhesive tape and the second adhesive tape may be arranged to be spaced apart from each other by a second gap, wherein the first gap may be twice as large as the second gap.

[0018] The first gap may be about 2 mm or greater.

[0019] The thickness of the second tape may be 10% to 20% smaller than the thickness of the first tape.

[0020] The thickness of the second tape may be approximately 10% to about 20% greater than the thickness of the first tape.

[0021] According to one or more embodiments, a battery pack includes a battery cell stack in which a plurality of battery cells are stacked and battery cell joints arranged between the battery cells, wherein each of the battery cell joints includes: a first layer formed to correspond to a surface of one of the battery cells; and a second layer and a third layer arranged on opposite sides of the first layer and formed to correspond to the surface of the one of the battery cells.

[0022] The second and third layers may be harder than the first layer.

[0023] The first layer may be compressible.

[0024] The first layer may include ethylene vinyl acetate (EVA) foam or polyethylene (PE) foam.

[0025] The second layer and the third layer may each include a polycarbonate (PC) sheet.

[0026] The second layer and the third layer may have a thickness of about 0.1 mm or greater.

[0027]

[0011] Further aspects, features, and advantages in addition to those described above will become apparent from the provided detailed description, claims, and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and other aspects, features and advantages of certain embodiments of the present disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which: Figure 1 is an exploded view of a battery cell according to an embodiment; Figure 2 In assembled state Figure 1 A perspective view of a battery cell; Figure 3 is a partially exploded perspective view of a battery cell stack; Figure 4 (a) is along Figure 3 The line A-A' is taken to show the Figure 3 A cross-sectional view of a battery cell before expansion occurs. Figure 4 (b) is along Figure 3 The line A-A' is taken to show the Figure 3 A cross-sectional view showing a state in which swelling occurs in a battery cell; Figure 5 shows a plan view of a first battery cell joint according to an embodiment; Figure 6 is an exploded perspective view of a first battery cell joining portion according to an embodiment; Figure 7 (a) is along Figure 3 A cross-sectional view taken along line AA' showing a state in which the thickness of the second adhesive tape is smaller than the thickness of the first adhesive tape; Figure 7 (b) is along Figure 3 A cross-sectional view taken along line AA' in FIG. 1 showing a state in which the thickness of the second adhesive tape is greater than that of the first adhesive tape; Figure 8 is a partially exploded perspective view of a battery cell stack according to other embodiments; Figure 9 (a) is along Figure 8 The line C-C' is taken to show the Figure 8 A cross-sectional view of a battery cell before expansion occurs. Figure 9 (b) is along Figure 8 The line C-C' is taken to show the Figure 8 A cross-sectional view of a state where swelling occurs in a battery cell; and Figure 10 is an exploded perspective view of a joining portion of a second battery cell according to another embodiment. DETAILED DESCRIPTION

[0029] Reference will now be made in detail to the embodiments, examples of which are shown in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the embodiments presented may have different forms and should not be construed as being limited to the descriptions set forth herein. Therefore, the embodiments are described below solely with reference to the drawings to illustrate aspects of this specification. As used herein, the term "and / or" includes any and all combinations of one or more of the relevant listed items. Expressions such as "at least one of...", if following a list of elements, modify the entire list of elements, without modifying the individual elements of that list.

[0030] Hereinafter, a battery pack according to an embodiment will be described in detail with reference to the accompanying drawings. The terms or words used in the specification and claims should not be interpreted as limited to their ordinary meanings or dictionary meanings, but should be interpreted as meanings and concepts consistent with the technical concept of the present disclosure based on the principle of definability that the inventor can appropriately define the concept of the term in order to best explain his or her invention. Therefore, the embodiments described in this specification and the configurations shown in the drawings are only some of the most preferred embodiments of the present disclosure and do not represent the entire technical concept of the present disclosure. Therefore, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application. In addition, when used herein, "including", "comprising" and / or their variations refer to the presence of the mentioned features, quantities, steps, operations, components, elements and / or their groups, and do not exclude the presence or addition of one or more other features, quantities, operations, components, elements and / or groups. In addition, when describing an embodiment of the present disclosure, "may" and "may be" may include "one or more embodiments of the present disclosure".

[0031] In addition, to facilitate understanding of the disclosure, the accompanying drawings may not be drawn to scale, but the sizes of some components may be exaggerated. In addition, the same reference numerals may be assigned to the same components in different embodiments.

[0032] The statement that two compared objects are "the same" means that they are "substantially the same." Thus, substantially the same can include deviations that are considered low in the art, for example, less than 5%. In addition, the term "a certain parameter is uniform in a certain area" can refer to uniformity from an average perspective.

[0033] Although the first, second, etc. are used to describe various components, these components are of course not limited by these terms. These terms are only used to distinguish one component from another component, and unless specifically stated otherwise, the first component may also be the second component.

[0034] Throughout the specification, unless stated otherwise, each component may be singular or plural.

[0035] Placing any component on or at the “top (or bottom)” of a component means that any component is placed in contact with the top (or bottom) of the component, and may mean that other components may be placed between the component and any components disposed on (or under) the component.

[0036] In addition, when a component is described as being “connected,” “coupled,” or “combined” to another component, it should be understood that the components may be directly connected or combined with each other, but another component may be “interposed” between the respective components, or the respective components may be “connected,” “coupled,” or “combined” through other components. In addition, when a component is referred to as being electrically coupled to another component, this includes not only the case where the components are directly connected, but also the case where the components are connected to other intervening elements.

[0037] When "A and / or B" is mentioned throughout the specification, unless otherwise specifically stated, this means A, B, or A and B. That is, "and / or" includes all or any combinations of multiple listed items. When "C to D" is mentioned, this means C or higher and D or lower, unless otherwise specifically stated.

[0038] The terms used in this specification are used to describe the embodiments of the present disclosure and are not intended to limit the disclosure.

[0039] In the following, reference will be made to Figures 1 to 7 (b) in FIG. 1 describes a battery cell C according to an embodiment.

[0040] Figure 1 shows an exploded view of a battery cell C according to an embodiment, Figure 2 In assembled state Figure 1 A perspective view of a battery cell C, Figure 3 is a partially exploded perspective view of a battery cell stack. Figure 4 (a) shows the Figure 3 The state before the expansion of the battery cell C occurs, Figure 4 (b) in FIG. 1 shows a state after expansion occurs in the battery cell C. Figure 5 shows a plan view of a first battery cell joint portion according to an embodiment, Figure 6 is an exploded perspective view of a first battery cell joining portion according to an embodiment, Figure 7 (a) shows a state where the thickness of the second tape is smaller than that of the first tape. Figure 7 (b) in the figure shows a state where the thickness of the second adhesive tape is greater than the thickness of the first adhesive tape.

[0041] Reference Figure 1 and Figure 2, the battery cell C includes an electrode assembly 10, a receiving portion A in which the electrode assembly 10 is received, and a sealing portion TS extending along the edge of the receiving portion A to seal the receiving portion A. The electrode assembly 10 can be formed into a roll shape by winding a first electrode plate 11 and a second electrode plate 12 arranged to face each other with a separator 13 therebetween, or can be formed into a stack shape by stacking a plurality of first electrode plates 11 and second electrode plates 12 with a separator interposed therebetween. An electrode tab 15 forming a charge and discharge path can be connected to the electrode assembly 10. The electrode tab 15 may include two electrode tabs 15 of different polarities electrically connected to the electrode assembly 10, and the electrode tab 15 connected to the electrode assembly 10 within the receiving portion A can be pulled out to the outside of the receiving portion A through the front surface F of the receiving portion A.

[0042] The receiving portion A, in which the electrode assembly 10 is received, may be formed in a generally rectangular parallelepiped shape. More specifically, the receiving portion A may include a front surface F from which the electrode tab 15 protrudes, a rear surface R opposite the front surface F, a pair of main surfaces M connecting the front surface F and the rear surface R and occupying a relatively large area, and a pair of side surfaces D connecting the front surface F and the rear surface R and having a relatively small surface area. The main surface M may occupy the largest surface area among the surfaces of the receiving portion A and may be formed with a surface area larger than that of the front surface F, the rear surface R, and the side surfaces D. The front surface F, the rear surface R, and the pair of side surfaces D may be connected to the main surface M of the receiving portion A at different corners along the main surface M.

[0043] In an embodiment of the present disclosure, the main surface M and the side surface D may be formed in pairs at positions facing each other. For example, the main surface M may include a first main surface M1 and a second main surface M2 facing each other. Among the surfaces connecting the front surface F and the rear surface R, the surface with a relatively large surface area may correspond to the main surface M or the side surface M with a large surface area, and among the surfaces connecting the front surface F and the rear surface R, the surface with a relatively small surface area may correspond to the side surface D or the side surface D with a small surface area. Throughout this specification, the side surface D may refer to the side surface D with a small surface area, and more specifically, unless referred to as the large surface area side surface M, it may refer to the small surface area side surface D, and the large surface area side surface M may refer to the main surface M.

[0044] The battery cell C may further include a sealing portion TS formed along an edge of the accommodating portion A to seal the accommodating portion A. The accommodating portion A for accommodating the electrode assembly 10 and the sealing portion TS for sealing the accommodating portion A may be formed of an exterior material 20 continuously formed to surround the electrode assembly 10. That is, the exterior material 20 may surround the electrode assembly 10 and form the accommodating portion A for accommodating the electrode assembly 10, and the additional exterior material 20 remaining after the accommodating portion A is formed may form the sealing portion TS that seals the accommodating portion A.

[0045] The exterior material 20 may include a flexible exterior material 20 such as a layered structure, and more specifically, may include a metal layer 20a (such as an aluminum sheet) and an insulating layer 20b (such as a resin coating formed on both surfaces of the metal layer 20a). The metal layer 20a may be exposed to the outside through a cross-section where the exterior material 20 ends. As described below, the metal layer 20a may be exposed at the edge of the sealing portion TS, where the first exterior material 21 and the second exterior material 22 are combined to face each other with the electrode assembly 10 therebetween.

[0046] In an embodiment of the present disclosure, the exterior material 20 may include a first exterior material 21 and a second exterior material 22 that are combined to face each other with the electrode assembly 10 therebetween. The electrode assembly 10 may be located between the first exterior material 21 and the second exterior material 22. The first exterior material 21 and the second exterior material 22 may be folded to overlap each other by a folding portion 25 connecting the first exterior material 21 and the second exterior material 22. The portions in contact with each other may be bonded to each other along edge regions of the first exterior material 21 and the second exterior material 22 by thermal fusion or the like. Therefore, the inner regions of the first exterior material 21 and the second exterior material 22 that face each other with the electrode assembly 10 therebetween may be formed as an accommodating portion A, and the edge regions of the first exterior material 21 and the second exterior material 22 that are bonded to each other may be formed as a sealing portion TS.

[0047] The sealing portion TS may be continuously formed along the edge regions of the first and second exterior materials 21 and 22, excluding the folded portion 25. More specifically, the sealing portion TS may include a platform portion T extending in the direction of the front surface F of the accommodating portion A and a side sealing portion S extending in the direction of the side surface D of the accommodating portion A. The electrode tab 15 connected to the electrode assembly 10 within the accommodating portion A may be pulled out of the accommodating portion A through the platform portion T extending in the direction of the front surface F of the accommodating portion A. In addition, a protective circuit module may be placed on the platform portion T, and the electrode tab 15 pulled out through the platform portion T may be bent to connect to the protective circuit module placed on the platform portion T.

[0048] The side seal portion S may include a main body Sb of the side seal portion S at a position corresponding to the accommodating portion A and a front end Sa extending from the main body Sb of the side seal portion S to a position outside the accommodating portion A. The side seal portion S may be folded toward the accommodating portion A to reduce the area occupied by the entire battery cell C, and the side seal portion S may be folded toward the accommodating portion A through a first fold and a second fold. That is, in the first fold, the main body Sb of the side seal portion S at a position corresponding to the accommodating portion A and the front end Sa of the side seal portion S at a position outside the accommodating portion A are folded together. After the first fold, a second fold may be performed, wherein the front end Sa is folded so as to be recessed toward the edge where the front surface F of the accommodating portion A and the platform portion T contact each other. Through the first and second folds, the main body Sb of the side seal portion S is folded toward the side surface D of the accommodating portion A and can be placed on the side surface D. In the side seal portion S, the front end Sa may form a dog-ear shape that is recessed toward the edge formed by the front surface F of the accommodating portion A and the platform portion T.

[0049] At the edge of the side seal S, the metal layer 20a may be exposed through a cross-section where the outer material 20 forming the side seal S ends. Because the main body Sb of the side seal S is folded onto the side surface D of the accommodating portion A, the metal layer 20a exposed through the edge of the main body Sb can be prevented from protruding from the side surface D of the accommodating portion A. The front end Sa of the side seal S is folded so as to be concavely recessed toward the edge formed by the front surface F of the accommodating portion A and the platform portion T. Therefore, the metal layer 20a exposed through the edge of the front end Sa of the side seal S can be prevented from protruding from the front surface F of the accommodating portion A. In other words, the side seal S can be prevented from protruding from the side surface D and the front surface F of the accommodating portion A and can be folded into a shape that conforms to the outer shape of the accommodating portion A while the main body Sb of the side seal S is folded onto the side surface D of the accommodating portion A and the front end Sa of the side seal S is folded toward the edge where the platform portion T and the front surface F of the accommodating portion A contact each other.

[0050] In an embodiment of the present disclosure, the outer shape of the battery cell C may generally follow the outer shape of the receiving portion A, and the outer surfaces of the receiving portion A (i.e., the front surface F, rear surface R, main surface M, and side surfaces D) may generally represent the outer surfaces of the battery cell C. The battery cell C may also include a sealing portion TS that seals the receiving portion A when the electrode assembly 10 is received in the receiving portion A. The sealing portion TS (i.e., at least the side sealing portions S) may be folded toward the side surfaces D and front surface F of the receiving portion A to minimize the area occupied by the battery cell C. Therefore, the outer shape of the battery cell C may generally follow the outer shape of the receiving portion A, and thus, the front surface F, rear surface R, main surface M, and side surfaces D of the receiving portion A may generally represent the front, rear, main surface, and side surfaces of the battery cell C. A platform portion T may be formed at the front of the battery cell C and generally take the form of a plate rather than a surface, so that the protection circuit module is seated thereon. If the outer shape of the battery cell C is considered to be approximately rectangular, the front of the battery cell C may represent the front surface F of the receiving portion A.

[0051] Reference Figures 3 to 7 In (b), a battery pack according to an embodiment may include a battery cell stack 1000 in which a plurality of battery cells are stacked, and a first battery cell joint 100 disposed between the plurality of battery cells. The first battery cell joint 100 may include a first adhesive tape 110 and a second adhesive tape 120, the first adhesive tape 110 being formed to correspond to an edge of a surface of one of the battery cells, and the second adhesive tape 120 being formed to correspond to a center portion of a surface of the battery cell C. The first adhesive tape and the second adhesive tape form a single layer and are spaced apart from each other. Surfaces of the first adhesive tape 110 and the second adhesive tape 120 may include an adhesive material to bond two battery cells C disposed on either side of the first battery cell joint 100 to each other.

[0052] The first tape 110 can be formed to be harder than the second tape 120. That is, the first tape can include a hard material, and the second tape can include a soft material. The first tape 110 can include hard rubber. If the battery pack falls, the impact can be absorbed by the first tape 110 including hard rubber. The second tape 120 can include a compressible material. For example, the second tape 120 can include a sponge. If expansion of the battery cell C occurs, the second tape 120 including a sponge can effectively absorb the expansion. The first battery cell joint 100 can include different materials including the first tape 110 and the second tape 120.

[0053] In this manner, first battery cell joints 100 can be positioned between battery cells C so that first adhesive tape 110 and second adhesive tape 120, each of first battery cell joints 100 made of different materials, form a single layer. Thus, if the battery pack including battery cell stack 1000 is dropped, the impact resulting from the drop is absorbed by first adhesive tape 110, which is made of a hard material. Furthermore, when expansion occurs in battery cells C of battery cell stack 1000, particularly when the central portion of the surface of battery cell C expands, second adhesive tape 120, positioned at a position corresponding to the expanded portion, absorbs the expansion of battery cell C.

[0054] In addition, the first adhesive tape 110 for ensuring durability and the second adhesive tape 120 for absorbing expansion form only one layer between the battery cells C. Therefore, the volume of the battery pack can be prevented from increasing, and a compact battery pack structure can be manufactured.

[0055] According to an embodiment, the first adhesive tape 110 may be formed to surround the second adhesive tape 120. The first adhesive tape 110 may be provided between the battery cells C at positions corresponding to edges of the battery cells C, that is, if the battery pack falls with any portion thereof, the first adhesive tape 110 may absorb impact applied to the battery cells C at the edge positions of the battery cells C.

[0056] In addition, the second adhesive tape 120 is provided at the center of the surface of the battery cell C where expansion is likely to occur. Therefore, the second adhesive tape can effectively absorb the expansion of the battery cell C.

[0057] According to an embodiment, the first and second tapes 110, 120 may be arranged to be separated from each other by a second gap G2. When the first tape 110 is pressed by pressure between the battery cells C, the first tape 110 may expand in a direction perpendicular to the pressing direction. Similarly, the second tape 120 may receive the expansion pressure of the battery cells C and expand in a direction perpendicular to the direction of the expansion pressure. If the first and second tapes 110, 120 expand in a direction perpendicular to the direction of the received pressure, interference may occur between the first and second tapes 110, 120. As a result, the battery pack's impact absorption and the expansion absorption of the battery cells C may not be properly performed. Therefore, a second gap G2 is formed between the first and second tapes 110, 120 to prevent interference between the two components when the first and second tapes 110, 120 expand in a direction perpendicular to the direction of the pressure received from the battery cells C. The second gap G2 may, for example, be 1 mm or larger. If the second gap G2 is less than 1 mm, the gap between the first and second tapes 110, 120 may be filled, and mutual interference may occur.

[0058] According to an embodiment, the first tape 110 can be formed to have a first gap G1, which includes a portion 130 cut on one side. The second tape 120 can be expanded in a direction perpendicular to the direction of the expansion pressure by receiving expansion pressure from the battery cell C. When the second tape 120 is expanded, the first tape 110 can receive pressure from the second tape 120 in a direction perpendicular to the direction of the pressure from the battery cell C. Assuming that the first tape 110 is formed in a ring shape, if pressure is applied to the ring shape from the center of the ring shape, the ring shape may not be able to withstand the pressure and the ring shape may be damaged. Therefore, since the first gap G1 is formed by cutting one side of the first tape 110 having a circumferential shape, when the expansion pressure received by the second tape 120 from the battery cell C is transmitted to the first tape 110, the first gap G1 increases and the pressure transmitted from the second tape 120 can be absorbed. Therefore, there may be only slight deformation to the extent that the first gap G1 widens. In addition, when the second adhesive tape 120 is pressed due to the expansion of the battery cell C, the second adhesive tape 120 is pushed into the space of the first gap G1 and may functionally maintain the shape of the first battery cell joining part 100 .

[0059] According to an embodiment, the first gap G1 may be formed to be twice the size of the second gap G2. The first gap G1 may be, for example, 2 mm or larger. Since the first gap G1 is formed to be larger than the second gap G2, when the second adhesive tape 120 is unrolled, the accommodation space of the portion of the second adhesive tape 120 pushed into the space formed by the first gap G1 can be made wider.

[0060] Reference Figure 7 In (a), the thickness T2 of the second tape 120 may be 10% to 20% smaller than the thickness T1 of the first tape 110. This is to further reduce deformation of the second tape 120 due to pressure absorption when the battery cells C expand, because the volume absorption function for expansion does not consider the thickness difference (T1-T2) between the thickness T1 of the first tape 110 and the thickness T2 of the second tape 120.

[0061] Optionally, the thickness T2' of the second adhesive tape 120 may be 10% to 20% greater than the thickness T1' of the first adhesive tape 110. This further increases the area of ​​contact between the battery cells C and the second adhesive tape 120, thereby increasing the area available for absorbing expansion of the battery cells C. Consequently, the battery cell expansion absorption capability of the second adhesive tape 120 may be improved.

[0062] Reference Figures 8 to 10 , battery packs according to other embodiments will be described. Figures 1 to 7 The content shown in (b) is Figures 8 to 10 There is no need to repeat.

[0063] Figure 8 FIG. 1 shows a partially exploded perspective view of a battery cell stack 1000 according to other embodiments. Figure 9 (a) shows the Figure 8 The state before the expansion of the battery cell, Figure 9 (b) shows the state after swelling occurs in the battery cell, and Figure 10 An exploded perspective view of a second battery cell joining portion according to other embodiments is shown.

[0064] Reference Figures 8 to 10 According to an embodiment, a battery pack may include a battery cell stack 1000 in which a plurality of battery cells are stacked. Second battery cell joints 200 may be provided between the plurality of battery cells C constituting the battery cell stack 1000. Each of the second battery cell joints 200 may include a first layer 210 formed to correspond to a surface portion of the battery cell C, and a second layer 220 and a third layer 230 respectively provided on both sides of the first layer 210, and the second layer 220 and the third layer 230 are formed on both sides of the first layer 210 to correspond to the surface portion of the battery cell C.

[0065] The surface portions of the second layer 220 and the third layer 230 may include an adhesive material to bond the two battery cells C disposed on both sides of the second battery cell bonding portion 200 to each other. In addition, the second layer 220 and the third layer 230 may maintain a bonded state with the first layer 210 disposed therebetween.

[0066] The second layer 220 and the third layer 230 may be formed to be harder than the first layer 210. That is, the second layer 220 and the third layer 230 may include a hard material, and the first layer 210 may include a compressible soft material.

[0067] The second layer 220 and the third layer 230 may comprise, for example, a hard polycarbonate (PC) sheet. The second layer 220 and the third layer 230, comprised of the hard PC sheet material, are placed in direct contact with the surface of the battery cells C and can absorb shock if the battery pack is dropped. In some embodiments, the second layer 220 and the third layer 230 may have a thickness of 0.1 mm or greater. If the thickness is less than 0.1 mm, the durability of the second layer 220 and the third layer 230 may be reduced, making it difficult to absorb shock if the battery pack is dropped.

[0068] The first layer 210 may be disposed between the second layer 220 and the third layer 230 and may include a compressible material. For example, the first layer 210 may include ethylene vinyl acetate (EVA) foam or polyethylene (PE) foam. When the battery cells C expand, the first layer 210, including the EVA foam or PE foam, can effectively absorb the expansion. Therefore, as described above, the second battery cell joint 200 may include different materials for the first layer 210, the second layer 220, and the third layer 230.

[0069] In this manner, the first layer 210, the second layer 220, and the third layer 230, each made of different materials, form a stacked structure and are disposed between the battery cells C. If the battery pack including the battery cell stack 1000 is dropped, the impact caused by the drop is absorbed by the second layer 220 and the third layer 230, each made of a hard material. Furthermore, when the battery cells C expand, the center portion of the surface of the battery cells C expands, and the first layer 210, which is disposed at a position corresponding to the center portion, absorbs the expansion of the battery cells C.

[0070] According to the present disclosure, there is provided a battery pack including a battery cell joint portion that improves reliability of the battery pack in case the battery pack falls and simultaneously prevents an increase in thickness of the battery pack by securing expansion spaces between battery cells.

[0071] However, the effects that can be achieved by the present disclosure are not limited to the above-mentioned effects, and those skilled in the art will clearly understand other technical effects that are not mentioned through the description herein.

[0072] Although the present disclosure has been described above with limited examples and drawings, the present disclosure is not limited thereto, and of course, various modifications and changes may be made by those skilled in the art within the scope of the equivalents of the technical spirit of the present disclosure and the scope of the appended described claims.

[0073] It should be understood that the embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should generally be considered applicable to other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the appended claims.

Claims

1. A battery pack, comprising: a battery cell stack comprising a plurality of battery cells; as well as The battery cell joint is provided between the plurality of battery cells. Wherein, each of the battery cell joints comprises: a first adhesive tape arranged to correspond to an edge of a surface of one of the plurality of battery cells; and a second adhesive tape arranged to correspond to a central portion of the surface of the one battery cell among the plurality of battery cells, and The first adhesive tape and the second adhesive tape form a single layer and are spaced apart from each other.

2. The battery pack according to claim 1, wherein: The first tape is harder than the second tape.

3. The battery pack according to claim 2, wherein: The second tape is compressible.

4. The battery pack according to claim 2, wherein: The second tape includes sponge.

5. The battery pack according to claim 2, wherein: The first tape includes rubber.

6. The battery pack according to claim 1, wherein: The first tape surrounds the second tape.

7. The battery pack according to claim 1, wherein: The first tape and the second tape are spaced apart from each other by a gap.

8. The battery pack according to claim 7, wherein: The gap is 1 mm or more.

9. The battery pack according to claim 1, wherein: The first tape has a gap cut on one side.

10. The battery pack according to claim 9, wherein: The gap is a first gap, wherein the first adhesive tape and the second adhesive tape are arranged to be spaced apart from each other by a second gap, The first gap is twice the size of the second gap.

11. The battery pack according to claim 10, wherein: The first gap is 2 mm or greater.

12. The battery pack according to claim 1, wherein: The thickness of the second adhesive tape is 10% to 20% smaller than the thickness of the first adhesive tape.

13. The battery pack according to claim 1, wherein The thickness of the second adhesive tape is 10% to 20% greater than the thickness of the first adhesive tape.

14. A battery pack, comprising: a battery cell stack comprising a plurality of battery cells; as well as The battery cell joint is provided between the plurality of battery cells. Wherein, each of the battery cell joints comprises: a first layer formed to correspond to a surface of one of the plurality of battery cells; and A second layer and a third layer are provided on two opposite sides of the first layer and are formed to correspond to the surface of the one battery cell among the plurality of battery cells.

15. The battery pack according to claim 14, wherein: The second layer and the third layer are harder than the first layer.

16. The battery pack according to claim 15, wherein: The first layer is compressible.

17. The battery pack according to claim 15, wherein: The first layer includes ethylene vinyl acetate foam or polyethylene foam.

18. The battery pack according to claim 15, wherein: The second layer and the third layer each include a polycarbonate sheet.

19. The battery pack according to claim 18, wherein: The second layer and the third layer have a thickness of 0.1 mm or more.

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