Tab and battery module

Abstract

The present disclosure provides a tab and a battery module capable of further preventing re-contact of a fused portion even if a fuse is fused due to an overcurrent. The tab according to the present disclosure is provided with: a tab body having a first tab part, a second tab part, and a connection part connecting the first tab part and the second tab part; and a thermal expansion member that is in contact with at least the connection portion, where a direction in which the first tab portion and the second tab portion are arranged via the connection portion is a Y direction, a thickness direction of the tab body is a Z direction, and a direction perpendicular to each of the Y direction and the Z direction is an X direction. The size of the connecting part in the X direction is respectively smaller than the size of the first tab part in the X direction and the size of the second tab part in the X direction; the thermal expansion member is provided with at least any two of an X contact surface in contact with the tab main body in the X direction, a Y contact surface in contact with the tab main body in the Y direction, and a Z contact surface in contact with the tab main body in the Z direction.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a tab and a battery module. BACKGROUND

[0002] A flat type temperature fuse is disclosed in Patent Literature 1, in which a recess is provided on an insulating substrate, a low-melting-point metal body as a fuse element is disposed on the insulating substrate with a gap from the bottom surface of the recess, and an outer covering body is covered on the low-melting-point metal body with an elastic body or a foaming layer in a compressed state covering the recess.

[0003] According to the flat type temperature fuse described in Patent Literature 1, it is disclosed that when the low-melting-point metal body melts, the elastic body or the foaming layer restores the shape in a manner of filling the recess, at the upper end edge portion of the recess, the molten low-melting-point metal body is sheared and deformed, the molten low-melting-point metal body is divided at this portion, and the passage of the molten low-melting-point metal body is blocked.

[0004] Prior Art Documents

[0005] Patent Literature

[0006] Patent Literature 1: Japanese Patent Application Laid-Open No. 9-17303 Utility Model Contents

[0007] Technical Problem to be Solved by the Utility Model

[0008] In the flat type temperature fuse described in Patent Literature 1, the elastic body or the foaming layer in a compressed state is elastically deformed in a direction of filling the recess. That is, the direction in which the elastic body or the foaming layer is elastically deformed is one direction. Therefore, in the case where a force is applied to the elastic body or the foaming layer in a direction opposite to the direction of filling the recess, the molten low-melting-point metal bodies can be connected to each other again.

[0009] The present disclosure is completed in view of such a point. That is, the main object of the present disclosure is to provide a tab and a battery module in which recontacting of a fuse breaking portion is further prevented after a fuse is broken by flowing of an overcurrent.

[0010] Technical Solution for Solving the Technical Problem

[0011] The tab of the present disclosure has:

[0012] a tab main body having a first tab portion, a second tab portion, and a connecting portion connecting the first tab portion and the second tab portion; and

[0013] a thermal expansion member contacting at least the connecting portion,

[0014] A direction in which the first tab portion and the second tab portion are arranged via the connection portion is set as a Y direction, a thickness direction of the tab main body is set as a Z direction, and a direction perpendicular to the Y direction and the Z direction is set as an X direction,

[0015] The connection portion has a size in the X direction that is smaller than a size of the first tab portion in the X direction and a size of the second tab portion in the X direction,

[0016] The thermal expansion member has at least any two of an X contact surface that contacts the tab main body in the X direction, a Y contact surface that contacts the tab main body in the Y direction, and a Z contact surface that contacts the tab main body in the Z direction.

[0017] The battery module of the present disclosure has:

[0018] The tab described above;

[0019] A battery electrically connected to the tab; and

[0020] A battery holder that houses the battery.

[0021] Effects of the utility model

[0022] According to the present disclosure, even if overcurrent flows to cause the connection portion that connects the first tab portion and the second tab portion to be fused, the present disclosure can further prevent recontacting of the fused portion. Specifically, since the thermal expansion member has at least any two of an X contact surface that contacts the tab main body in the X direction, a Y contact surface that contacts the tab main body in the Y direction, and a Z contact surface that contacts the tab main body in the Z direction, at least two contact surfaces are used, and recontacting of the first tab portion and the second tab portion at the time of fusion can be more appropriately prevented. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a schematic exploded perspective view of a battery pack of the present disclosure.

[0024] Figure 2 is a schematic exploded perspective view of a battery module housed in a battery pack of the present disclosure.

[0025] Figure 3 is a schematic perspective view of a tab of the first embodiment.

[0026] Figure 4 is a schematic exploded perspective view of a tab of the first embodiment.

[0027] Figure 5 is a schematic plan view of a tab main body of the first embodiment.

[0028] Figure 6Ais a schematic plan view of the tab of the first embodiment.

[0029] Figure 6B is a schematic cross-sectional view of the tab taken along Figure 6A the B-B line.

[0030] Figure 6C is a schematic cross-sectional view of the tab taken along Figure 6A the C-C line.

[0031] Figure 7A is a schematic plan view illustrating a case where a fuse is generated on the tab of the first embodiment.

[0032] Figure 7B is a schematic cross-sectional view of the tab taken along Figure 7A the B-B line.

[0033] Figure 7C is a schematic cross-sectional view of the tab taken along Figure 7A the C-C line.

[0034] Figure 8 is a schematic exploded perspective view of the tab of the second embodiment.

[0035] Figure 9 is a schematic plan view of the tab body of the second embodiment.

[0036] Figure 10A is a schematic cross-sectional view of the tab of the second embodiment as viewed from the X direction.

[0037] Figure 10B is a schematic cross-sectional view illustrating a case where a fuse is generated on the tab of the second embodiment.

[0038] Figure 11A is a schematic perspective view of a modification example of the tab of the second embodiment.

[0039] Figure 11B is a schematic cross-sectional view of the modification example of the tab of the second embodiment as viewed from the X direction.

[0040] Figure 12 is a schematic exploded perspective view of the tab of the third embodiment.

[0041] Figure 13 is a schematic plan view of the tab of the third embodiment.

[0042] Figure 14A is a schematic plan view illustrating a case where a fuse is generated on the tab of the third embodiment.

[0043] Figure 14B is a schematic cross-sectional view illustrating a case where a fuse is generated on the tab of the third embodiment.

[0044] Reference Signs List

[0045] 1, 1A, 1B, 1C, 1D: tab; 10, 10A, 10B, 10C, 10D: tab body; 11A, 11B, 11C, 11D: first tab portion; 11I: insertion portion; 12A, 12B, 12C, 12D: second tab portion; 12T: terminal connecting portion; 13A, 13B, 13C, 13D: connecting portion; 20A, 20B, 20C, 20D: thermal expansion member; 21A, 21B: base portion; 22A, 22B: protruding portion; AXY: side surface; BX, CX, DX: X contact surface; DX1: first X contact surface; DX2: second X contact surface; CY, DY: Y contact surface; AZ, BZ, CZ, DZ: Z contact surface; F1: first curved portion; F2: second curved portion; F3: first hook portion; F4: second hook portion; F5: third curved portion; F6: fourth curved portion; BM: battery module; BP: battery pack; C1: first connecting site; C2: second connecting site; C3: third connecting site; CB: battery; CN: connector; CS: case; CS1: first case; CS2: second case; E1: outer side edge; E2: outer side edge; E3: outer side edge; H1, H2: hole; HD: battery holder; IH: insertion hole; L1: dimension; L2: dimension; L3: dimension; L4: maximum dimension; NT: negative terminal; OP: opening portion; PT: positive terminal; SB: control substrate; T1: dimension; T2: dimension; W1: first wall portion; W2: second wall portion; θ: curved angle. DETAILED DESCRIPTION

[0046] Hereinafter, a tab, a battery module provided with the tab, and a battery pack provided with the battery module according to one embodiment of the present disclosure will be described in more detail. Although the description will be made with reference to the drawings as needed, various elements in the drawings are schematically and exemplarily shown for understanding the present disclosure, and the appearance and the dimension ratio and the like can be different from the actual ones.

[0047] The "Z direction" in the present specification means a thickness direction of an object (for example, a battery pack), and a drawing viewed from the Z direction is a plan view. The "Y direction" means a height direction of a battery used in the battery pack, and a drawing viewed from the Y direction is a front view. The "X direction" means a direction orthogonal to the Z direction and the Y direction, and a drawing viewed from the X direction is a side view. That is, the X direction, the Y direction, and the Z direction mean a relationship of being orthogonal to each other, respectively. Note that in the drawings, the X direction, the Y direction, and the Z direction are illustrated, and the direction of an arrow means a positive direction (or a + direction), and the direction opposite to the direction of the arrow means a negative direction (or a - direction). In addition, the term "degree" mentioned in the present specification means that a variation of several percent, for example, ±10% can be included.

[0048] [Battery pack]

[0049] The battery pack BP of the present disclosure will be described with reference to Figure 1 while being described. Figure 1 is a schematic exploded perspective view of the battery pack BP.

[0050] The battery pack BP can have a case CS and a battery module BM housed in the case CS (refer to Figure 1 ). Note that detailed description of the battery module BM will be given in the following items.

[0051] The case CS can be composed of a first case CS1 and a second case CS2. In addition, a housing space in which the battery module BM is housed can also be composed of the first case CS1 and the second case CS2. Note that in the example of Figure 1 , a manner in which the housing space is composed of two cases (the first case CS1 and the second case CS2) is illustrated, but it is not limited to this manner, and it can also be composed of three or more cases.

[0052] The material of the case CS can be any material, and it can be a resin material (for example, plastic) or a metal material. For example, as a resin material, polycarbonate (PC), acrylonitrile butadiene styrene (ABS), polybutylene terephthalate (PBT), modified polyphenylene ether (m-PPE), polyamide (PA), and the like can be listed. For example, as a metal material, aluminum and the like can be listed. Note that from the viewpoint of more appropriately housing the battery module BM, the case CS can use a material with high rigidity.

[0053] A connector CN that is electrically connected to the battery module BM can be provided on the case CS. In the example illustrated in Figure 1 , a manner in which the connector CN is provided to the second case CS2 is illustrated, but the connector CN can also be provided to the first case CS1. The connector CN can be a terminal for taking out electric power from the battery module BM.

[0054] [Battery module]

[0055] The battery module BM of the present disclosure will be described with reference to Figure 2 while being described. Figure 2 is a schematic exploded perspective view of the battery module BM housed in the battery pack BP of the present disclosure.

[0056] The battery module BM of the present disclosure can have a battery CB, a battery holder HD, a tab 1, and a control substrate SB. Hereinafter, each structure will be described in detail.

[0057] -Battery-

[0058] The battery CB refers mainly to a chemical battery that converts chemical energy into direct current power through a chemical reaction. The battery CB used in the battery module BM of the present disclosure refers to a battery having a cylindrical shape with a cylindrical axis in the ±Y direction. Note that the shape of the battery can also be a shape other than a cylindrical shape (for example, an elliptical cylindrical shape, a rectangular columnar shape, or a polygonal columnar shape, etc.).

[0059] In the battery module BM of the present disclosure, two or more batteries CB can be provided. In addition, each battery CB can be arranged adjacently. For example, in the manner shown in FIG. 1, four batteries CB are arranged adjacently with each other in the ±X direction, combined in two columns in the +Z direction (a total of eight batteries CB can be provided). Note that the number of batteries and the manner of combination are not limited to those shown in FIG. 1. Figure 2 Figure 2

[0060] Battery holder

[0061] The battery holder HD can be a member that holds and / or fixes the battery CB within the accommodation space of the case CS. In the example shown in FIG. 2, the battery holder HD can be provided on the +Y direction side and the -Y direction side of the battery CB. That is, the battery holder HD can be inserted into the battery CB in a manner of sandwiching the battery CB from both sides in the ±Y direction, thereby holding and / or fixing the battery CB. Note that the manner of sandwiching the battery CB from both sides in the ±Y direction shown in FIG. 2 can be constituted by two members, but the battery holder HD can also be constituted by three or more members. In addition, the battery holder HD can be provided as a single member constituted by one member, and the battery CB can be held and / or fixed by inserting the battery CB from the +Y direction or the -Y direction. Figure 2 Figure 2

[0062] As shown in FIG. 3, the battery holder HD can be provided with an opening portion OP that exposes the positive terminal and the negative terminal of the battery CB. The battery CB (positive terminal and negative terminal) can be electrically connected to the tab 1 via the opening portion OP. Figure 2

[0063] Tab

[0064] As shown in FIG. 4, the tab 1 can be provided to sandwich the battery CB in the ±Y direction. The tab 1 can also electrically connect the positive terminal PT and / or the negative terminal NT of the adjacent battery CB to each other. In the example shown in FIG. 4, the tab 1 can electrically connect the positive terminal PT of the battery CB adjacent in the ±Z direction to each other (or the negative terminal NT to each other), in parallel. Figure 2 Figure 2 Figure 2 ​​​​​​​In the meantime, the tab 1 can also be electrically connected in series by electrically connecting the positive terminal PT and the negative terminal NT of the battery CB adjacent in the ±X direction. Note that a detailed description of the tab 1 will be given later. In addition, as will be described later, the tab 1 of the present disclosure can adopt any one of the tab 1A of the first embodiment to the tab 1D of the fourth embodiment.

[0065] Control substrate

[0066] The control substrate SB is described in one example Figure 2 In the meantime, the tab 1 can also be electrically connected in series by electrically connecting the positive terminal PT and the negative terminal NT of the battery CB adjacent in the ±X direction. Note that a detailed description of the tab 1 will be given later. In addition, as will be described later, the tab 1 of the present disclosure can adopt any one of the tab 1A of the first embodiment to the tab 1D of the fourth embodiment.

[0067] [Tab of the first embodiment]

[0068] The tab 1A of the first embodiment will be described with reference to Figures 3 to 7C While being described. The tab 1A of the present embodiment has: a tab main body 10A including a first tab portion 11A, a second tab portion 12A, and a connection portion 13A, and a thermal expansion member 20A (see Figure 4 in particular). Note that in the present specification, the direction in which the first tab portion 11A and the second tab portion 12A are arranged via the connection portion 13A (more specifically, the direction in which the first tab portion 11A and the second tab portion 12A are adjacent via the connection portion 13A) is set as the Y direction, the thickness direction of the tab main body 10A is set as the Z direction, and the direction perpendicular to the Y direction and the Z direction is set as the X direction.

[0069] The first tab portion 11A is a portion to be electrically connected to the control substrate SB, and can have electrical conductivity. The "electrical conductivity" in the present specification means that the volume resistivity is 10 5 Ω·cm or less. As shown in Figure 4 , the first tab portion 11A extends from the connection portion 13A in the -Y direction. In addition, the first tab portion 11A can have an insertion portion 11I to be inserted into the insertion hole IH of the control substrate SB. The insertion portion 11I extends in the +Z direction, and the insertion portion 11I and the control substrate SB can be electrically connected.

[0070] The second tab portion 12A is a portion to be electrically connected to the positive terminal PT or the negative terminal NT of the battery CB, and can have electrical conductivity. The second tab portion 12A extends from the connection portion 13A in the +Y direction. In addition, the second tab portion 12A can have a terminal connection portion 12T (see Figure 4), the terminal connecting portion 12T extends in the -Z direction and is connected to the positive electrode terminal PT or the negative electrode terminal NT.

[0071] The connecting portion 13A connects the first tab portion 11A and the second tab portion 12A (see Figure 5 ). In addition, the connecting portion 13A functions as a fuse by being melted by flowing of an overcurrent in the connecting portion 13A.

[0072] By forming the hole H1 in the tab main body 10A, the connecting portion 13A can be positioned outside the hole H1. Note that the hole H1 in the present embodiment can also be circular in plan view. Note that the shape of the hole H1 is not limited to a circular shape, and can also be an oblong shape, an elliptical shape, or a polygonal shape (a triangular shape or a quadrangular shape, etc.).

[0073] Here, in the present specification, as Figure 5 indicated, the boundary of the connecting portion 13A and the first tab portion 11A is defined by a boundary line R1 that is parallel to the X direction and that is in contact with the hole H1 for forming the connecting portion 13A on the most -Y direction side. Similarly, as Figure 5 indicated, the boundary of the connecting portion 13A and the second tab portion 12A is defined by a boundary line R2 that is parallel to the X direction and that is in contact with the hole H1 for forming the connecting portion 13A on the most +Y direction side. Therefore, in the present specification, the range from the boundary line R1 to the boundary line R2 is taken as the connecting portion 13A, the side opposite to the connecting portion 13A with the boundary line R1 as a reference is taken as the first tab portion 11A, and the side opposite to the connecting portion 13A with the boundary line R2 as a reference is taken as the second tab portion 12A.

[0074] As Figure 5 indicated, the dimension L3 of the connecting portion 13A in the X direction is smaller than the dimension L1 of the first tab portion 11A in the X direction and the dimension L2 of the second tab portion 12A in the X direction, respectively. The "dimension of the connecting portion in the X direction" in the present specification means the dimension L3 at the central position of the range from the boundary of the first tab portion 11A and the connecting portion 13A to the boundary between the second tab portion 12A and the connecting portion 13A (see Figure 5 ). In addition, the "dimension of the first tab portion in the X direction" in the present specification means the dimension L1 of the first tab portion 11A at the boundary position of the first tab portion 11A and the connecting portion 13A (see Figure 5 ). In addition, the "dimension of the second tab portion in the X direction" in the present specification means the dimension L2 of the second tab portion 12A at the boundary position of the second tab portion 12A and the connecting portion 13A (see Figure 5 ).

[0075] The thermal expansion component 20A is a component that expands in the ±X, ±Y, and / or ±Z directions when heat is applied. Examples of such a thermal expansion component 20A include thermally expandable rubbers in which thermally expandable graphite and the like are added to rubber materials such as natural rubber (NR), styrene-butadiene rubber (SBR), ethylene propylene rubber (EPDM), chloroprene rubber (CR), acrylonitrile rubber (NBR), urethane rubber (U), silicone rubber (Si), butyl rubber (IIR), and mixtures thereof.

[0076] As a general technical concept of the thermal expansion component disclosed herein, the thermal expansion component shall have at least two of the following: an X-contact surface that contacts the tab body in the X direction, a Y-contact surface that contacts the tab body in the Y direction, and a Z-contact surface that contacts the tab body in the Z direction. The X-contact surface referred to in this specification includes a surface on the tab body that contacts the tab body along its extension in the +X and / or -X directions. Similarly, the Y-contact surface includes a surface on the tab body that contacts the tab body along its extension in the +Y and / or -Y directions, and the Z-contact surface includes a surface on the tab body that contacts the tab body along its extension in the +Z direction.

[0077] The thermal expansion member 20A of the first embodiment can be composed of a base portion 21A and a protrusion 22A located in the +Z direction of the base portion 21A and inserted into the hole H1 (see reference). Figure 4 As an example, such as Figure 4 As shown, the base portion 21A can be prismatic, and the protrusion 22A can be cylindrical. It should be noted that the shapes of the base portion 21A and the protrusion 22A are not limited to these shapes. Figure 4 In this manner, for example, the base portion 21A can be cylindrical, elliptical, or oblong, and the protrusion 22A can be a prism (e.g., a rhomboid prism or a rectangular prism).

[0078] like Figure 4 , Figure 6C As shown, the base portion 21A of the first embodiment has a Z-contact surface AZ that contacts the electrode body (first electrode portion 11A, second electrode portion 12A, and connecting portion 13A) in the +Z direction. Furthermore, as... Figure 4 , Figure 6B As shown, the protrusion 22A has a side surface AXY. Furthermore, the side surface AXY may include an X-contact surface that contacts the tab body 10A in the X direction and a Y-contact surface that contacts the tab body 10A in the Y direction.

[0079] With the tab 1A of the first embodiment described above, when the connection portion 13A is fused by flowing of an overcurrent, heat caused by the overcurrent propagates to the heat expansion member 20A to expand the heat expansion member 20A. Specifically, the heat expansion member 20A expands in the X direction, the Y direction, and the Z direction (refer to Figures 7A to 7C ). Here, in the tab 1 of the present disclosure, the heat expansion member 20 has at least any two of the X contact surface, the Y contact surface, and the Z contact surface. Thus, unlike the technical idea of the related art in which it is elastically deformed in one direction, it is possible to apply stress in at least two directions. Thus, even if the connection portion 13A is fused by flowing of an overcurrent, it is possible to further prevent re-contacting at the fused portion.

[0080] More specifically, with the tab 1A of the first embodiment (for example, Figures 6A to 6C ), the heat expansion member 20A has a protruding portion 22A that protrudes from the Z contact surface AZ in the Z direction, and a side surface AXY that functions as the X contact surface and / or the Y contact surface is provided to the protruding portion 22A. Thus, when heat is generated at the connection portion 13A by flowing of an overcurrent, as shown in Figure 7B , the side surface AXY (X contact surface and Y contact surface) of the protruding portion 22A expands in the ±X direction and the ±Y direction. Thereby, stress is applied to separate the first tab portion 11A and the second tab portion 12A in the X direction and the Y direction. In addition, as shown in Figure 7C , the Z contact surface AZ of the base portion 21A expands in the +Z direction, thereby causing the first tab portion 11A and the second tab portion 12A to warp, and stress is applied to separate the first tab portion 11A and the second tab portion 12A. Thus, even if the connection portion 13A is fused by flowing of an overcurrent, since the first tab portion 11A and the second tab portion 12A are separated, it is possible to further prevent re-contacting at the fused portion.

[0081] In addition, with the tab 1A of the first embodiment (for example, Figures 6A to 6C ), the tab main body 10A has a hole H1, and the connection portion 13A is arranged outside the hole H1. In addition, the protruding portion 22A is inserted into the hole H1. With such a structure, by expansion of the protruding portion 22A, the side surface of the protruding portion 22A functions to press the connection portion 13A, and it is possible to further separate the first tab portion 11A and the second tab portion 12A.

[0082] In addition, as viewed in the Z direction (refer to Figure 6A ), the protruding portion 22A can also be fitted into the hole H1. When the protruding portion 22A is fitted into the hole H1, the protruding portion 22A and the hole H1 maintain a state in which they are in contact in the normal state of the battery pack 1. Thus, when the protruding portion 22A expands, pressing force generated by the expansion is rapidly applied to the connection portion 13A, and thus it is possible to effectively separate the first tab portion 11A and the second tab portion 12A.

[0083] It should be noted that, in this embodiment, the base portion 21A can be in contact with the terminal connection portion 12T of the second electrode ear portion 12A. That is, a Y-contact surface that contacts the second electrode ear portion 12A in the Y direction can be provided on the base portion 21A. With this structure, since the second electrode ear portion 12A can be further pressed in the Y direction by the expansion of the base portion 21A, the first electrode ear portion 11A and the second electrode ear portion 12A can be further separated.

[0084] [Additional structures for the tabs in the first embodiment]

[0085] In the preferred first embodiment of the electrode tab 1A, the maximum dimension T1 of the protrusion 22A in the Z direction can be greater than or equal to the thickness dimension T2 of the electrode tab body 10A (see reference). Figure 6B In other words, when viewed from the X direction, the protrusion 22A can be inserted into the hole H1 of the tab body 10A and protrude from the tab body 10A. If the protrusion 22A is in this manner, the pressing force can be increased and the first tab 11A and the second tab 12A can be effectively separated because the side of the protrusion 22A presses against the entire connecting portion 13A.

[0086] The maximum dimension L4 of the hole H1 in the tab body 10A in the X direction can be greater than or equal to the dimension L3 of the connecting part 13A in the X direction (see reference). Figure 5 If the dimensions are such, the resistance of the connection 13A is increased, and the connection 13A can be properly melted when an overcurrent flows through the tab 1A.

[0087] Specifically, in the form of the tab body 10A, the outer edge E1 of the first tab portion 11A, the outer edge E3 of the connecting portion 13A, and the outer edge E2 of the second tab portion 12A can be continuous. In other words, the outer edge E1 of the first tab portion 11A, the outer edge E3 of the connecting portion 13A, and the outer edge E2 of the second tab portion 12A can be flat. When the tab body 10A is formed in this shape, the connecting portion 13A can be provided simply by forming a hole H1 in the tab body 10A, enabling it to function as a fuse.

[0088] As a more specific way of the tab main body, it can be that the outer side edges E3 of the connection portions 13A are continuous from the two outer side edges El of the first tab portion 11A respectively, and the outer side edges E3 of the connection portions 13A are continuous from the two outer side edges E2 of the second tab portion 12A respectively. That is, the number of the connection portions 13A provided on the tab main body 10A can be provided at least two. With such a structure, since the connection portions 13A are connected to the first tab portion 11A and the second tab portion 12A at both ends, the tab 1A has a strong resistance to distortion, and it is difficult to break even if an external force is applied to the tab during normal use.

[0089] As a more specific way of the tab main body, it can be that the size of the connection portions 13A in the X direction becomes larger as it goes toward the first tab portion 11A, and the size of the connection portions 13A in the X direction becomes larger as it goes toward the second tab portion 12A. In other words, it can be that the size of the connection portions 13A in the X direction gradually becomes smaller as it goes toward the position where the overcurrent flows and is fused. With such a structure, it is possible to increase the resistance near the position where the connection portions 13A are fused and further promote heat generation. In addition, it is possible to increase the expansion of the thermal expansion member 20A that contacts at that position. Thereby, it is possible to increase the thermal expansion of the thermal expansion member 20A near the fusion position, and further separate the first tab portion 11A and the second tab portion 12A, and more effectively prevent the re-contact of the first tab portion 11A and the second tab portion 12A.

[0090] [Tab of the second embodiment]

[0091] Next, the tab 1B of the second embodiment will be described with reference to Figures 8 to 10B the drawings. Note that, in describing the tab 1B of the second embodiment, the description of points common to the description of the "tab of the first embodiment" described above will be appropriately omitted. That is, the following description will be made focusing on points different from the description of the "tab of the first embodiment" described above.

[0092] As shown in Figure 8 , the tab 1B of the second embodiment can be provided with a first bent portion Fl at the Y-direction end portion on the connection portion 13B side of the first tab portion 11B, the first bent portion Fl being bent in the Z direction and contacting a Y-contact surface BY on one side of the thermal expansion member 20B described later. In addition, a second bent portion F2 can also be provided at the Y-direction end portion on the connection portion 13B side of the second tab portion 12B, the second bent portion F2 being bent in the Z direction and contacting a Y-contact surface BY on the other side of the thermal expansion member 20B described later.

[0093] In one example shown in Figure 8 , the thermal expansion member 20B of the second embodiment is a polygonal shape in plan view. In addition, as shown in Figure 8As shown, the thermal expansion member 20B has a Y contact surface BY that contacts the first curved portion F1 and the second curved portion F2 respectively, and may also have an X contact surface BX that contacts the connecting portion 13B.

[0094] Compared to the second embodiment described above, the tab 1B (see reference) Figure 8 as well as Figure 10A When an overcurrent flows and the connection 13B melts, the heat caused by the overcurrent propagates to the thermal expansion member 20B, causing the thermal expansion member 20B to expand due to the heat (see reference). Figure 10B Specifically, stress in the X direction is applied to the connecting portion 13B by the X contact surface BX of the thermal expansion member 20B, causing the first electrode lug 11B and the second electrode lug 12B to separate in the X direction. More specifically, in Figure 8 Stress in the +X direction is applied to the connecting portion 13B on the +X direction side as shown. Figure 8 A stress in the -X direction is applied to the connecting portion 13B on the -X direction side, causing the first electrode lug 11B and the second electrode lug 12B to separate. Additionally, stress in the Y direction is applied to the first bent portion F1 and the second bent portion F2 respectively through the Y contact surface BY of the thermal expansion member 20B, causing the first electrode lug 11B and the second electrode lug 12B to separate in the Y direction. More specifically, a stress in the -Y direction is applied to the first bent portion F1, and a stress in the +Y direction is applied to the second bent portion F2, causing the first electrode lug 11B and the second electrode lug 12B to separate.

[0095] Even in the second embodiment of the tab 1B, since the thermal expansion member 20B has an X contact surface BX and a Y contact surface BY, unlike the prior art technique of elastically deforming it in one direction, it can apply stress in at least two directions. Therefore, even if the connection part 13B melts due to the flow of overcurrent, re-contact at the melted part can be further prevented.

[0096] As a preferred configuration for the first curved portion F1 and the second curved portion F2, the bending angle θ of the first curved portion F1 and the second curved portion F2 can be an angle greater than 90° and less than 180° (refer to...). Figure 10A The bending angle mentioned in this specification refers to the angle on the obtuse side when the first bent portion F1 and the second bent portion F2 are bent. When the bending angle θ of the first bent portion F1 and the second bent portion F2 is greater than 90° and less than 180°, the first bent portion F1 and the second bent portion F2 can be subjected to stress in the Z direction from the thermal expansion member 20B. As described above, in addition to the stress in the X direction from the X contact surface BX and the stress in the Y direction from the Y contact surface BY, the tab body 10B is also subjected to stress in the Z direction from the thermal expansion member 20B, thereby further preventing re-contact of the fused portion.

[0097] As a preferred second embodiment of the tab 1B, as shown in Figure 9 the connecting portion 13B can have a first connecting site B1 connected to the first tab portion 11B, a second connecting site B2 connected to the second tab portion 12B, and a third connecting site B3 connecting the first connecting site B1 and the second connecting site B2. In addition, the first connecting site B1 can have a tapered portion in which the dimension in the X direction becomes smaller as it goes toward the third connecting site B3, and the second connecting site B2 can have a tapered portion in which the dimension in the X direction becomes smaller as it goes toward the third connecting site B3. If such a structure is adopted, the dimensions of the first connecting site B1 and the second connecting site B2 in the X direction gradually become smaller as they go toward the position at which the overcurrent flows and is fused, and thus the resistance in the vicinity of the fusion position of the connecting portion 13B can be increased to further promote heat generation. Therefore, the expansion of the thermal expansion member 20B that contacts in the vicinity of the third connecting site B3, in which the resistance is high, can be increased. As a result, the thermal expansion of the thermal expansion member 20B in the vicinity of the fusion position is increased, the first tab portion 11B and the second tab portion 12B are further separated, and the recontacting of the first tab portion 11B and the second tab portion 12B can be more effectively prevented.

[0098] As a way to realize the first connecting site B1, the second connecting site B2, and the third connecting site B3 described above, as shown in Figure 9 the tab main body 10B has a hole H2, the connecting portion 13B is arranged outside the hole H2, and the hole H2 can have a shape that has a trapezoidal portion corresponding to the first connecting site B1, the second connecting site B2, and the third connecting site B3 when viewed in the Z direction. With such a structure, since the hole H2 has a portion in which the third connecting site B3, which has a high resistance, is elongated, the expansion of the thermal expansion member 20B that contacts in the vicinity of the third connecting site B3 can be further increased. As a result, the thermal expansion of the thermal expansion member 20B in the vicinity of the fusion position can be further increased, the first tab portion 11B and the second tab portion 12B are further separated, and the recontacting of the first tab portion 11B and the second tab portion 12B can be more effectively prevented.

[0099] Furthermore, the thermal expansion member 20B has a shape corresponding to the shape of the hole H2, and the thermal expansion member 20B can be fitted into the hole H2. With such a structure, since the thermal expansion member 20B contacts the hole H2, the heat generated at the fusion position can be appropriately transmitted to the thermal expansion member 20B.

[0100] [Tab of the third embodiment]

[0101] Next, referring to Figure 11A and Figure 11BThe tab 1C of the third embodiment will be described. Note that, in describing the tab 1C of the third embodiment, points common to the description of the "tab of the second embodiment" in the above-described items will be appropriately omitted. That is, the following description will be made focusing on points different from the description of the "tab of the second embodiment" in the above-described items.

[0102] As shown in Figure 11A and Figure 11B , the tab 1C of the third embodiment can be provided with a first hook portion F3 that contacts a Z contact surface CZ of a thermal expansion member 20C described later at a Z-direction end portion of the first bent portion Fl, and a second hook portion F4 that contacts the Z contact surface CZ of the thermal expansion member 20C at a Z-direction end portion of the second bent portion F2.

[0103] In addition, the thermal expansion member 20C of the third embodiment can also be provided with Z contact surfaces CZ that contact the first hook portion F3 and the second hook portion F4, respectively (see Figure 11B ). Further, the thermal expansion member of the third embodiment is provided with Y contact surfaces CY that contact the first bent portion Fl and the second bent portion F2, respectively, as described in the [tab of the second embodiment], and can also be provided with an X contact surface CX that contacts the connecting portion 13C.

[0104] If the tab 1C of the third embodiment is as described above, since the thermal expansion member 20C is provided with the Z contact surfaces CZ, and is provided with the X contact surface CX and the Y contact surface CY, it can act on stress in three directions, unlike the technical idea of the prior art in which it is elastically deformed in one direction. Therefore, even if an overcurrent flows and the connecting portion 13C is fused, recontacting at the fused portion can be further prevented.

[0105] [Tab of the fourth embodiment and battery module provided with the tab of the fourth embodiment]

[0106] Next, the tab 1D of the fourth embodiment and the battery module BM provided with the tab 1D of the fourth embodiment will be described with reference to Figures 12 to 14B . Note that, in describing the tab 1D of the fourth embodiment, points common to the description of the "tab of the first embodiment" in the above-described items will be appropriately omitted. In addition, in describing the battery module BM provided with the tab 1D of the fourth embodiment, points common to the description of the "battery module" in the above-described items will be appropriately omitted. The following description will be made focusing on points different from the above-described description.

[0107] The tab 1D of the fourth embodiment can be provided with a third bent portion F5 (see Figure 12 ) that contacts with an X contact surface (a first X contact surface DX1) on one side of the thermal expansion member 20D described later on the +X direction side of the first tab portion 11D, and a fourth bent portion F6 (see Figure 12 ) that contacts with an X contact surface (a second X contact surface DX2) on the other side of the thermal expansion member 20D described later on the -X direction side of the second tab portion 12D.

[0108] Further, as shown in Figure 12 , the third bent portion F5 can extend from the first tab portion 11D toward the -Z direction, and as shown in Figure 12 , the fourth bent portion F6 can extend from the second tab portion 12D toward the -Z direction.

[0109] In addition, the tab main body 10D of the fourth embodiment can not have the hole H1 of the tab main body 10A of the first embodiment, and the first tab portion 11D and the second tab portion 12D can be connected by at least one connection portion 13D.

[0110] The thermal expansion member 20D of the fourth embodiment is not provided with the protruding portion 22A of the thermal expansion member 20A of the first embodiment. FIG. 14, which shows an example, is a polygonal shape (a quadrangular prism shape) when viewed from above.

[0111] Further, the thermal expansion member 20D of the fourth embodiment can be provided with the first X contact surface DX1 that contacts with the third bent portion F5 described above (see Figure 13 ), and the second X contact surface DX2 that contacts with the fourth bent portion F6 described above and is opposite to the first X contact surface DX1 (see Figure 13 ). Further, the thermal expansion member 20D of the fourth embodiment can be provided with the Z contact surface DZ that contacts with the tab main body 10D (see Figure 13 ).

[0112] With regard to the tab 1D of the fourth embodiment described above (see Figure 13 ), when an overcurrent flows and the connection portion 13D is fused, heat caused by the overcurrent propagates to the thermal expansion member 20D, and the thermal expansion member 20D expands due to the heat (see Figure 14A and Figure 14B ). Specifically, as shown in Figure 14AAs shown, the first X contact surface DX1 of the thermal expansion member 20D expands, and through the third bending portion F5 that contacts the first X contact surface DX1, stress is generated that causes the first electrode tab 11D to move towards the +X direction. Furthermore, the second X contact surface DX2 of the thermal expansion member 20D expands, and through the fourth bending portion F6 that contacts the second X contact surface DX2, stress is generated that causes the second electrode tab 12D to move towards the -X direction. Therefore, since the first electrode tab 11D and the second electrode tab 12D separate from each other, re-contact between the first electrode tab 11D and the second electrode tab 12D can be more effectively prevented. Furthermore, as... Figure 14B As shown, the first electrode lug 11D and the second electrode lug 12D are warped by the expansion of the Z contact surface DZ of the thermal expansion member 20D in the +Z direction, thereby applying stress to further separate the first electrode lug 11D and the second electrode lug 12D.

[0113] Therefore, unlike the prior art technique of elastically deforming the tab 1D in one direction, the tab 1D according to the fourth embodiment can apply stress in at least two directions. Therefore, even if the connection 13D melts due to an overcurrent, re-contact at the melted portion can be further prevented.

[0114] As a preferred method for the connecting part 13D, such as Figure 13 As shown, the connecting part 13D can be a single unit. Therefore, by melting one connecting part 13D, the electrical connection between the first electrode lug 11D and the second electrode lug 12D can be properly cut off.

[0115] Furthermore, in the case where the connecting part 13D is a single unit, such as Figure 13 As shown, the connecting portion 13D can connect the first electrode ear 11D and the second electrode ear 12D at the center in the X direction. When the connecting portion 13D is located at the center in the X direction, as... Figure 14A As shown, the expansion of the thermal expansion member 20D causes the first electrode tab 11D to move in a rotational manner toward the +X direction and the second electrode tab 12D to move in a rotational manner toward the -X direction, thereby enabling the first electrode tab 11D and the second electrode tab 12D to be properly separated in the X direction.

[0116] As a more suitable way to separate the first tab 11D and the second tab 12D, the battery module BM equipped with the tab 1D of the fourth embodiment may also be given a structure that promotes separation. For example, Figure 12As shown, a first wall portion W1 that opposes the X contact surface (first X contact surface DX1) of one side of the thermal expansion member 20D and is adjacent to the third bent portion F5, and a second wall portion W2 that opposes the X contact surface (second X contact surface DX2) of the other side of the thermal expansion member 20D and is adjacent to the fourth bent portion F6 can be provided for the battery holder HD that houses the battery CB. With this structure, expansion of the portion of the thermal expansion member 20D that opposes the second wall portion W2 is suppressed, and expansion of the portion of the thermal expansion member 20D on the side of the third bent portion F5 is promoted. Thus, stress acting in the +X direction from the thermal expansion member 20D toward the third bent portion F5 can be further generated. Accordingly, the thermal expansion member 20D can further generate stress that moves the first tab portion 11D to the +X direction side. Likewise, expansion of the portion that opposes the first wall portion W1 can be suppressed, and expansion of the portion of the thermal expansion member 20D on the side of the fourth bent portion F6 is promoted, and stress acting in the -X direction from the thermal expansion member 20D toward the fourth bent portion F6 can be further generated. Accordingly, the thermal expansion member 20D can further generate stress that moves the second tab portion 12D to the -X direction side.

[0117] Further, in the battery holder HD, the first wall portion W1 can oppose the fourth bent portion F6, and the second wall portion W2 can oppose the third bent portion F5. The "oppose" in the present specification includes not only a case where the components facing each other completely overlap each other, but also a case where the components facing each other overlap each other only partially. With this structure, expansion of the thermal expansion member 20D is suppressed by the first wall portion W1 and the second wall portion W2, and stress that separates the first tab portion 11D and the second tab portion 12D from each other can be imparted to the third bent portion F5 and the fourth bent portion F6.

[0118] As a more preferable mode, the size of the first wall portion W1 can be equal to the size of the third bent portion F5, and the size of the second wall portion W2 can be equal to the size of the fourth bent portion F6. If such a relationship is present, optimization of the balance between suppression of expansion of the thermal expansion member 20D by the first wall portion W1 and the second wall portion W2 and imparting of stress that separates the first tab portion 11D and the second tab portion 12D from each other by the third bent portion F5 and the fourth bent portion F6 can be achieved.

[0119] Note that the embodiments disclosed this time are examples in all aspects and are not limited to the explanation. Thus, the technical scope of the present disclosure is not interpreted in accordance with the embodiments described above only, but is interpreted based on the recitations in the claims. In addition, the technical scope of the present disclosure includes all modifications equivalent to or within the scope of the claims.

[0120] The tab, the battery module, and the battery pack according to the present disclosure are as described below.

[0121] A tab having:

[0122] a tab main body having a first tab portion, a second tab portion, and a connecting portion connecting the first tab portion and the second tab portion; and

[0123] a thermal expansion member contacting at least the connecting portion,

[0124] a direction in which the first tab portion and the second tab portion are arranged via the connecting portion is set as a Y direction, a thickness direction of the tab main body is set as a Z direction, and a direction perpendicular to the Y direction and the Z direction is set as an X direction,

[0125] a size of the connecting portion in the X direction is smaller than a size of the first tab portion in the X direction and a size of the second tab portion in the X direction,

[0126] the thermal expansion member has at least any two of an X contact surface contacting the tab main body in the X direction, a Y contact surface contacting the tab main body in the Y direction, and a Z contact surface contacting the tab main body in the Z direction.

[0127] A tab according to <1>,

[0128] the thermal expansion member has a protruding portion protruding from the Z contact surface toward the Z direction,

[0129] the X contact surface and / or the Y contact surface are provided in the protruding portion.

[0130] A tab according to <2>,

[0131] the tab main body has a hole, and the connecting portion is disposed outside the hole,

[0132] the protruding portion is inserted into the hole.

[0133] A tab according to <3>,

[0134] the protruding portion is fitted with the hole as viewed in the Z direction.

[0135] A tab according to any one of <2> to <4>,

[0136] a maximum size of the protruding portion in the Z direction is equal to or greater than a thickness size of the tab main body.

[0137] A tab according to any one of <3> or <4> or <5> referring to <3>,

[0138] The maximum dimension of the hole in the X direction is equal to or greater than the dimension of the connecting portion in the X direction.

[0139] <7> The tab according to any one of <1> to <6>,

[0140] A first bent portion is provided at a Y direction end portion on the connecting portion side in the first tab portion, and is bent toward the Z direction and contacts the Y contact surface on one side of the thermal expansion member,

[0141] A second bent portion is provided at a Y direction end portion on the connecting portion side in the second tab portion, and is bent toward the Z direction and contacts the Y contact surface on the other side of the thermal expansion member.

[0142] <8> The tab according to any one of <7>,

[0143] A first hook portion is provided at a Z direction end portion of the first bent portion, and contacts the Z contact surface of the thermal expansion member,

[0144] A second hook portion is provided at a Z direction end portion of the second bent portion, and contacts the Z contact surface of the thermal expansion member.

[0145] <9> The tab according to any one of <1> to <8>,

[0146] The connecting portion has a first connecting site connected to the first tab portion, a second connecting site connected to the second tab portion, and a third connecting site connecting the first connecting site and the second connecting site,

[0147] The first connecting site has a tapered portion in which the dimension in the X direction becomes smaller as it goes toward the third connecting site,

[0148] The second connecting site has a tapered portion in which the dimension in the X direction becomes smaller as it goes toward the third connecting site.

[0149] <10> The tab according to <9>,

[0150] The tab body has a hole, and the connecting portion is disposed outside the hole,

[0151] When viewed in the Z direction, the shape of the hole has a trapezoidal portion corresponding to the first connecting site, the second connecting site, and the third connecting site,

[0152] The thermal expansion member is fitted into the hole.

[0153] <11> The tab according to any one of <1> to <10>,

[0154] A third bent portion is provided on one side of the X direction in the first tab portion in contact with the X contact surface on one side of the thermal expansion member,

[0155] A fourth bent portion is provided on the other side of the X direction in the second tab portion in contact with the X contact surface on the other side of the thermal expansion member.

[0156] <12> A battery module comprising:

[0157] The tab according to any one of <1> to <11>;

[0158] A battery cell electrically connected to the tab; and

[0159] A battery holder housing the battery cell.

[0160] <13> A battery module comprising:

[0161] The tab according to <11>;

[0162] A battery cell electrically connected to the tab; and

[0163] A battery holder housing the battery cell,

[0164] The battery holder comprises a first wall portion adjacent to the third bent portion at the X contact surface on one side of the thermal expansion member, and a second wall portion adjacent to the fourth bent portion at the X contact surface on the other side of the thermal expansion member.

[0165] Industrial applicability

[0166] The present disclosure can be appropriately used for a tab, a battery module, and a battery pack in which recontact of a fused portion can be prevented even if a fuse is fused by flowing an overcurrent.

Claims

1. A tab characterized by comprising: a tab main body including a first tab portion, a second tab portion, and a connecting portion connecting the first tab portion and the second tab portion; and a thermal expansion member contacting at least the connecting portion. A direction in which the first tab portion and the second tab portion are arranged via the connecting portion is set as a Y direction, a thickness direction of the tab main body is set as a Z direction, and a direction perpendicular to the Y direction and the Z direction is set as an X direction. A size of the connecting portion in the X direction is smaller than a size of the first tab portion in the X direction and a size of the second tab portion in the X direction, respectively. The thermal expansion member includes at least any two of an X contact surface contacting the tab main body in the X direction, a Y contact surface contacting the tab main body in the Y direction, and a Z contact surface contacting the tab main body in the Z direction.

2. The tab according to claim 1, wherein the thermal expansion member includes a protruding portion protruding from the Z contact surface toward the Z direction, the X contact surface and / or the Y contact surface are provided in the protruding portion.

3. The tab according to claim 2, wherein the tab main body includes a hole, and the connecting portion is disposed outside the hole, the protruding portion is inserted into the hole.

4. The tab according to claim 3, wherein the protruding portion is fitted to the hole as viewed in the Z direction.

5. The tab according to claim 2, wherein a maximum size of the protruding portion in the Z direction is equal to or greater than a thickness of the tab main body.

6. The tab according to claim 3, wherein a maximum size of the hole in the X direction is equal to or greater than a size of the connecting portion in the X direction.

7. The tab according to claim 1, wherein a first bent portion is provided at a Y direction end portion of the first tab portion on a side of the connecting portion, the first bent portion being bent toward the Z direction and contacting a Y contact surface on one side of the thermal expansion member, a second bent portion is provided at a Y direction end portion of the second tab portion on a side of the connecting portion, the second bent portion being bent toward the Z direction and contacting a Y contact surface on the other side of the thermal expansion member.

8. The tab according to claim 7, wherein a first hook portion is provided at a Z direction end portion of the first bent portion, the first hook portion contacting a Z contact surface of the thermal expansion member, a second hook portion is provided at a Z direction end portion of the second bent portion, the second hook portion contacting the Z contact surface of the thermal expansion member.

9. The tab according to claim 1, wherein the connecting portion includes a first connecting portion connecting the first tab portion, a second connecting portion connecting the second tab portion, and a third connecting portion connecting the first connecting portion and the second connecting portion, the first connecting portion includes a tapered portion in which a size in the X direction decreases as it approaches the third connecting portion, the second connecting portion includes a tapered portion in which a size in the X direction decreases as it approaches the third connecting portion.

10. The tab according to claim 9, wherein ​ The tab body has a hole, and the connecting portion is disposed outside the hole, The shape of the hole has trapezoidal portions corresponding to the first, second, and third connecting portions when viewed in the Z direction, The thermal expansion member is fitted into the hole.

11. The tab according to claim 1, wherein A third bent portion is provided on one side of the X direction in the first tab portion in contact with the X contact surface on one side of the thermal expansion member, A fourth bent portion is provided on the other side of the X direction in the second tab portion in contact with the X contact surface on the other side of the thermal expansion member.

12. A battery module, comprising: The battery module has: the tab according to claim 1; a battery cell electrically connected to the tab; and a battery holder that houses the battery cell.

13. A battery module, comprising: The battery module has: the tab according to claim 11; a battery cell electrically connected to the tab; and a battery holder that houses the battery cell, The battery holder has: a first wall portion adjacent to the third bent portion at the X contact surface on one side of the thermal expansion member, and a second wall portion adjacent to the fourth bent portion at the X contact surface on the other side of the thermal expansion member.

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