Tab and battery module

Abstract

To provide a tab which further prevents re-contact of a blowout location even if overcurrent flows and a fuse blows out, and a battery module.SOLUTION: A tab 1A comprises: a tab body 10A including a first tab part 11A, a second tab part 12A and a connection part 13A connecting the first tab part 11A and the second tab part 12A; and a thermal expansion member 20A in contact with at least the connection part 13A. A direction in which the first tab part 11A and the second tab part 12A are disposed in parallel while interposing the connection part therebetween is defined as a Y direction, a thickness direction of the tab body 10A is defined as a Z direction, and a direction which is vertical to the Y direction and the Z direction is defined as an X direction. A dimension L3 of the connection part 13A in the X direction is smaller than a dimension L1 of the first tab part 11A in the X direction and a dimension L2 of the second tab part 12A in the X direction. The thermal expansion member 20A includes at least any two of an X contact face AX in contact with the tab body 10A in the X direction, a Y contact face AY in contact with the tab body 10A in the Y direction and a Z contact face AZ in contact with the tab body 10A in the Z direction.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] Patent Document 1 discloses a flat temperature fuse in which a recess is provided in an insulating substrate, a low-melting-point metal body serving as a fuse element is disposed on the insulating substrate with a gap maintained between the bottom surface of the recess, and an outer casing is placed over the low-melting-point metal body via a compressed elastic body or foam layer that covers the recess.

[0003] According to the flat thermal fuse described in Patent Document 1, when the low-melting-point metal body melts, the elastic body or foam layer recovers its shape to fill the recess, and the molten low-melting-point metal body is shear-deformed at the upper edge of the recess, causing the molten low-melting-point metal body to split at this point, thereby cutting off the flow of electricity through the molten low-melting-point metal body. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 9-17303 Summary of the Invention [Problem to be solved by the invention]

[0005] In the flat thermal fuse described in Patent Document 1, the compressed elastic body or foam layer elastically deforms in a direction that fills the recesses. In other words, the elastic body or foam layer elastically deforms in one direction. Therefore, if a force is applied to the elastic body or foam layer in a direction opposite to the direction that fills the recesses, there is a risk that the molten low-melting-point metal bodies will reconnect to each other.

[0006] The present disclosure has been made in light of this viewpoint, and a primary object of the present disclosure is to provide a tab and a battery module that can more effectively prevent re-contact at the blown point after an overcurrent flows and the fuse blows. [Means for solving the problem]

[0007] The tabs in this disclosure are: a tab main body including a first tab portion, a second tab portion, and a connection portion connecting the first tab portion and the second tab portion; a thermal expansion member in contact with at least the connection portion, a direction in which the first tab portion and the second tab portion are aligned via a connection portion is defined as a Y direction, a thickness direction of the tab main body is defined as a Z direction, and a direction perpendicular to each of the Y direction and the Z direction is defined as an X direction; a dimension of the connection portion in the X direction is smaller than a dimension of the first tab portion in the X direction and a dimension of the second tab portion in the X direction; The thermal expansion member has at least two of an X contact surface that comes into contact with the tab main body in the X direction, a Y contact surface that comes into contact with the tab main body in the Y direction, and a Z contact surface that comes into contact with the tab main body in the Z direction.

[0008] The battery module of the present disclosure includes: The tabs mentioned above, a battery electrically connected to the tab; The battery is provided with a battery holder for accommodating the battery. [Effects of the Invention]

[0009] According to the present disclosure, even if an overcurrent flows and the connection portion connecting the first tab portion and the second tab portion melts, it is possible to more effectively prevent the melted portion from coming into contact again. Specifically, the thermal expansion member has at least two of an X contact surface that comes into contact with the tab main body in the X direction, a Y contact surface that comes into contact with the tab main body in the Y direction, and a Z contact surface that comes into contact with the tab main body in the Z direction. Therefore, by using at least two contact surfaces, it is possible to more appropriately prevent the first tab portion and the second tab portion from coming into contact again when the connection portion melts. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic exploded perspective view of a battery pack according to the present disclosure. [Figure 2] FIG. 2 is a schematic exploded perspective view of a battery module housed in the battery pack of the present disclosure. [Figure 3] FIG. 3 is a schematic perspective view of the tab of the first embodiment. [Figure 4] FIG. 4 is a schematic exploded perspective view of the tab of the first embodiment. [Figure 5] FIG. 5 is a schematic plan view of the tab main body of the first embodiment. [Figure 6A] FIG. 6A is a schematic plan view of the tab of the first embodiment. [Figure 6B] FIG. 6B is a schematic cross-sectional view of the tab taken along line BB in FIG. 6A. [Figure 6C] FIG. 6C is a schematic cross-sectional view of the tab taken along line CC in FIG. 6A. [Figure 7A] FIG. 7A is a schematic plan view illustrating a case where a meltdown occurs in the tab of the first embodiment. [Figure 7B] FIG. 7B is a schematic cross-sectional view of the tab taken along line BB in FIG. 7A. [Figure 7C] FIG. 7C is a schematic cross-sectional view of the tab taken along line CC in FIG. 7A. [Figure 8] FIG. 8 is a schematic exploded perspective view of the tab of the second embodiment. [Figure 9] FIG. 9 is a schematic plan view of a tab main body according to the second embodiment. [Figure 10A] FIG. 10A is a schematic cross-sectional view of the tab of the second embodiment as viewed from the X direction. [Figure 10B] FIG. 10B is a schematic cross-sectional view illustrating a case where a meltdown occurs in the tab of the second embodiment. [Figure 11A] FIG. 11A is a schematic perspective view of a modified example of the tab of the second embodiment. [Figure 11B] FIG. 11B is a schematic cross-sectional view of a modified example of the tab of the second embodiment as viewed from the X direction. [Figure 12] FIG. 12 is a schematic exploded perspective view of a tab according to the third embodiment. [Figure 13] FIG. 13 is a schematic plan view of a tab according to the third embodiment. [Figure 14A] FIG. 14A is a schematic plan view illustrating a case where a meltdown occurs in a tab of the third embodiment. [Figure 14B] FIG. 14B is a schematic cross-sectional view illustrating a case where a meltdown occurs in the tab of the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] A tab, a battery module including the tab, and a battery pack including the battery module according to an embodiment of the present disclosure will be described in more detail below. While the description will be made with reference to drawings as needed, the various elements in the drawings are merely shown schematically and for illustrative purposes to facilitate understanding of the present disclosure, and the appearance and dimensional ratios may differ from those of the actual objects.

[0012] In this specification, the "Z direction" refers to the thickness direction of an object (e.g., a battery pack), and a drawing viewed from the Z direction is a plan view. The "Y direction" refers to the 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" refers to the direction perpendicular to the Z and Y directions, and a drawing viewed from the X direction is a side view. In other words, the X, Y, and Z directions are intended to be perpendicular to each other. Note that, in the drawings, the X, Y, and Z directions are shown, but the direction of the arrows is intended to be the positive direction (or + direction), and the direction opposite to the arrows is intended to be the negative direction (or - direction). Furthermore, the term "degree" used in this specification means that it may include a variation of a few percent, for example, ±10%.

[0013] [Battery pack] The battery pack BP of the present disclosure will be described with reference to Fig. 1. Fig. 1 is a schematic exploded perspective view of the battery pack BP.

[0014] The battery pack BP may include a case CS and a battery module BM housed in the case CS (see FIG. 1). The battery module BM will be described in detail below.

[0015] The case CS may be composed of a first case CS1 and a second case CS2. The first case CS1 and the second case CS2 may form a storage space that houses the battery module BM. Note that, although the example in Fig. 1 illustrates a mode in which the storage space is formed by two cases (the first case CS1 and the second case CS2), the present invention is not limited to this mode and the storage space may be composed of three or more cases.

[0016] The case CS may be made of any material, including a resin material (e.g., plastic) or a metal material. Examples of resin materials include polycarbonate (PC), acrylonitrile butadiene styrene (ABS), polybutylene terephthalate (PBT), modified polyphenylene ether (m-PPE), and polyamide (PA). Examples of metal materials include aluminum. To more appropriately accommodate the battery module BM, a highly rigid material may be used for the case CS.

[0017] The case CS may be provided with a connector CN that is electrically connected to the battery module BM. In the example shown in Fig. 1, the connector CN is provided on the second case CS2, but the connector CN may also be provided on the first case CS1. The connector CN may be a terminal for extracting power from the battery module BM.

[0018] [Battery module] The battery module BM of the present disclosure will be described with reference to Fig. 2. Fig. 2 is a schematic exploded perspective view of the battery module BM housed in the battery pack BP of the present disclosure.

[0019] The battery module BM of the present disclosure may include a battery CB, a battery holder HD, a tab 1, and a control board SB. Each component will be described in detail below.

[0020] -battery- The battery CB is intended to be a chemical battery that converts mainly chemical energy into DC power through a chemical reaction. The battery CB used in the battery module BM of the present disclosure is intended to be a cylindrical battery with a cylindrical axis in the ±Y direction. The shape of the battery may be a shape other than a cylindrical shape (for example, an elliptical cylinder, a rectangular column, a polygonal column, etc.).

[0021] The battery module BM of the present disclosure may include two or more batteries CB. The batteries CB may be arranged adjacent to each other. For example, in the embodiment shown in FIG. 2, four batteries CB may be arranged adjacent to each other in the ±X directions and stacked in two rows in the +Z direction (a total of eight batteries CB may be provided). The number of batteries and the stacking arrangement are not limited to the embodiment shown in FIG. 2.

[0022] -Battery holder- The battery holder HD may be a member that holds and / or secures the battery CB within the storage space of the case CS. In one example shown in FIG. 2, the battery holder HD may be provided on both the +Y and −Y sides of the battery CB. That is, the battery holder HD may fit into the battery CB so as to sandwich it from both ±Y sides, thereby holding and / or securing the battery CB. Note that in the embodiment shown in FIG. 2, the battery holder HD is configured with two members that sandwich the battery CB from both ±Y sides, but the battery holder HD may also be configured with three or more members. Also, the battery holder HD may be a single member, and the battery CB may be held and / or secured by inserting it from the +Y or −Y direction.

[0023] 2, the battery holder HD may be provided with an opening OP that exposes the positive and negative terminals of the battery CB. The battery CB (positive and negative terminals) may be electrically connected to the tab 1 through the opening OP.

[0024] -tab- As shown in FIG. 2, the tabs 1 may be arranged to sandwich the battery CB in the ±Y direction. The tabs 1 may electrically connect the positive electrode terminals PT and / or negative electrode terminals NT of adjacent batteries CB. In FIG. 2, which shows an example, the tabs 1 may electrically connect the positive electrode terminals PT (or the negative electrode terminals NT) of adjacent batteries CB in the ±Z direction, thereby electrically connecting them in parallel. Also, in FIG. 2, which shows an example, the tabs 1 may electrically connect the positive electrode terminals PT and negative electrode terminals NT of adjacent batteries CB in the ±X direction, thereby electrically connecting them in series. The tab 1 will be described in detail later. As will be described later, the tab 1 of the present disclosure may be any of the tabs 1A of the first embodiment to the tab 1D of the fourth embodiment.

[0025] -Control board- 2, which shows an example, the control board SB may be disposed on the outer surface of the battery holder HD. The control board SB may be provided with an insertion hole IH into which the tab 1 is inserted. As a result, the control board SB may receive power from the battery CB via the tab 1 connected through the insertion hole IH. The control board SB may also control the power output from the battery CB via the tab 1.

[0026] [Tab of the first embodiment] A tab 1A of the first embodiment will be described with reference to Figures 3 to 7C. The tab 1A of this embodiment includes a tab main body 10A including a first tab portion 11A, a second tab portion 12A, and a connecting portion 13A, and a thermal expansion member 20A (see Figure 4 in particular). In this specification, the direction in which the first tab portion 11A and the second tab portion 12A are aligned with each other via the connecting portion 13A (more specifically, the direction in which the first tab portion 11A and the second tab portion 12A are adjacent to each other with the connecting portion 13A in between) is defined as the Y direction, the thickness direction of the tab main body 10A is defined as the Z direction, and the direction perpendicular to both the Y direction and the Z direction is defined as the X direction.

[0027] The first tab portion 11A is a portion electrically connected to the control board SB and may have conductivity.5 It is intended that the electrical resistance be Ω·cm or less. As shown in FIG. 4, the first tab portion 11A extends in the -Y direction from the connection portion 13A. Furthermore, the first tab portion 11A may have an insertion portion 11I that is inserted into the insertion hole IH of the control board SB described above. The insertion portion 11I extends in the +Z direction, and the insertion portion 11I and the control board SB may be electrically connected.

[0028] The second tab portion 12A is a portion that electrically connects to the positive electrode terminal PT or the negative electrode terminal NT of the battery CB and may be conductive. The second tab portion 12A extends in the +Y direction from the connection portion 13A. Furthermore, the second tab portion 12A may have a terminal connection portion 12T (see FIG. 4) that extends in the -Z direction and is connected to the positive electrode terminal PT or the negative electrode terminal NT.

[0029] The connection portion 13A connects the first tab portion 11A and the second tab portion 12A (see FIG. 5). When an overcurrent flows through the connection portion 13A, the connection portion 13A melts down, and functions as a fuse.

[0030] The connecting portion 13A may be located outside the hole H1 by forming the hole H1 in the tab main body 10A. Note that the hole H1 in this embodiment may be circular in plan view. Note that the shape of the hole H1 is not limited to a circular shape, and may be an oval, an ellipse, or a polygonal shape (such as a triangular or rectangular shape).

[0031] Here, in this specification, the boundary between connection portion 13A and first tab portion 11A is defined by boundary line R1, which is closest to hole H1 for forming connection portion 13A in the -Y direction and is parallel to the X direction, as shown in Fig. 5. Similarly, the boundary between connection portion 13A and second tab portion 12A is defined by boundary line R2, which is closest to hole H1 for forming connection portion 13A in the +Y direction and is parallel to the X direction, as shown in Fig. 5. Therefore, in this specification, the range from boundary line R1 to boundary line R2 is defined as connection portion 13A, the side opposite connection portion 13A with boundary line R1 as the reference is defined as first tab portion 11A, and the side opposite connection portion 13A with boundary line R2 as the reference is defined as second tab portion 12A.

[0032] As shown in FIG. 5, the X-direction dimension L3 of the connecting portion 13A is smaller than the X-direction dimension L1 of the first tab portion 11A and the X-direction dimension L2 of the second tab portion 12A. The term "X-direction dimension of the connecting portion" used herein refers to the dimension L3 (see FIG. 5) at the center of the range from the boundary between the first tab portion 11A and the connecting portion 13A to the boundary between the second tab portion 12A and the connecting portion 13A. The term "X-direction dimension of the first tab portion" used herein refers to the dimension L1 (see FIG. 5) of the first tab portion 11A at the boundary between the first tab portion 11A and the connecting portion 13A. The term "X-direction dimension of the second tab portion" used herein refers to the dimension L2 (see FIG. 5) of the second tab portion 12A at the boundary between the second tab portion 12A and the connecting portion 13A.

[0033] The thermal expansion member 20A is a member that has the property of expanding in the ±X direction, ±Y direction, and / or ±Z direction when heat is applied. Examples of such a thermal expansion member 20A include thermal expansion rubbers 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), and butyl rubber (IIR), as well as mixtures of these rubbers to which thermally expandable graphite or the like has been added.

[0034] As a general technical concept of the thermal expansion member of the present disclosure, the thermal expansion member has at least two of 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. In this specification, the term "X contact surface" refers to a surface on the tab body that contacts the tab body on an extension line in the +X direction and / or the -X direction. Similarly, the term "Y contact surface" refers to a surface on the tab body that contacts the tab body on an extension line in the +Y direction and / or the -Y direction, and the term "Z contact surface" refers to a surface on the tab body that contacts the tab body on an extension line in the +Z direction.

[0035] The thermal expansion member 20A of the first embodiment may be configured with a base portion 21A and a protrusion 22A that is located in the +Z direction of the base portion 21A and is inserted into the hole H1 (see FIG. 4). As an example, as shown in FIG. 4, the base portion 21A may be prismatic, and the protrusion 22A may be cylindrical. Note that the shapes of the base portion 21A and the protrusion 22A are not limited to the form shown in FIG. 4. For example, the base portion 21A may be cylindrical, elliptical, or elongated, and the protrusion 22A may be a prismatic (e.g., rhombic or rectangular) column.

[0036] As shown in Figures 4 and 6C, the base portion 21A of the first embodiment has a Z contact surface AZ that comes into contact with the tab main body (the first tab portion 11A, the second tab portion 12A, and the connecting portion 13A) in the +Z direction. Also, as shown in Figures 4 and 6B, the protrusion 22A has a side surface AXY. The side surface AXY may include an X contact surface that comes into contact with the tab main body 10A in the X direction and a Y contact surface that comes into contact with the tab main body 10A in the Y direction.

[0037] In the tab 1A of the first embodiment described above, when an overcurrent flows and melts the connection portion 13A, heat resulting from the overcurrent propagates to the thermal expansion member 20A, causing the thermal expansion member 20A to expand. Specifically, the thermal expansion member 20A expands in the X, Y, and Z directions (see FIGS. 7A to 7C). Here, in the tab 1 of the present disclosure, the thermal expansion member 20 has at least two of the X, Y, and Z contact surfaces. Therefore, unlike the prior art technical concept of elastic deformation in one direction, stress can be applied in at least two directions. Therefore, even if an overcurrent flows and melts the connection portion 13A, re-contact at the melted portion can be more effectively prevented.

[0038] More specifically, compared to the tab 1A of the first embodiment (see, for example, FIGS. 6A to 6C), the thermal expansion member 20A includes a protruding portion 22A that protrudes in the Z direction from a Z contact surface AZ, and the protruding portion 22A has a side surface AXY that also serves as an X contact surface and / or a Y contact surface. Therefore, when an overcurrent flows and heat is generated in the connection portion 13A, as shown in FIG. 7B, the side surface AXY (the X contact surface and the Y contact surface) of the protruding portion 22A expands in the ±X and ±Y directions. This causes stress to act to separate the first tab portion 11A and the second tab portion 12A in the X and Y directions. Furthermore, as shown in FIG. 7C, the Z contact surface AZ of the base portion 21A expands in the +Z direction, causing stress to act to warp the first tab portion 11A and the second tab portion 12A, separating the first tab portion 11A and the second tab portion 12A. Therefore, even if an overcurrent flows and the connection portion 13A melts down, the first tab portion 11A and the second tab portion 12A are separated from each other, so that the melted portion can be more effectively prevented from coming into contact again.

[0039] Furthermore, compared to the tab 1A of the first embodiment (FIGS. 6A to 6C), the tab main body 10A has a hole H1, and the connection portion 13A is disposed outside the hole H1. The protrusion 22A is inserted into the hole H1. With this configuration, the expansion of the protrusion 22A causes the side surface of the protrusion 22A to press against the connection portion 13A, thereby further separating the first tab portion 11A and the second tab portion 12A.

[0040] Also, when viewed along the Z direction (see FIG. 6A), the protrusion 22A may be fitted into the hole H1. When the protrusion 22A is fitted into the hole H1, the protrusion 22A and the hole H1 are maintained in contact with each other in the normal state of the battery pack 1. Therefore, when the protrusion 22A expands, the pressing force generated by the expansion acts quickly on the connection portion 13A, effectively separating the first tab portion 11A and the second tab portion 12A.

[0041] In this embodiment, the base portion 21A may be in contact with the terminal connection portion 12T of the second tab portion 12A. That is, the base portion 21A may be provided with a Y contact surface that comes into contact with the second tab portion 12A in the Y direction. With this configuration, the expansion of the base portion 21A can act to further press the second tab portion 12A in the Y direction, thereby further separating the first tab portion 11A and the second tab portion 12A.

[0042] [Additional configuration of the tab in the first embodiment] In a preferred aspect of the tab 1A of the first embodiment, the maximum dimension T1 in the Z direction of the protrusion 22A may be equal to or greater than the thickness dimension T2 of the tab main body 10A (see FIG. 6B). In other words, the protrusion 22A may be inserted into the hole H1 of the tab main body 10A and protrude from the tab main body 10A when viewed from the X direction. With this aspect of the protrusion 22A, the side surface of the protrusion 22A presses against the entire connecting portion 13A, thereby increasing the pressing force and effectively separating the first tab portion 11A and the second tab portion 12A.

[0043] The maximum dimension L4 in the X direction of the hole H1 provided in the tab main body 10A may be equal to or greater than the dimension L3 in the X direction of the connection portion 13A (see FIG. 5). With this dimensional relationship, the electrical resistance of the connection portion 13A is increased, and the connection portion 13A can be appropriately melted down when an overcurrent flows through the tab 1A.

[0044] In a specific embodiment of the tab main 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 may 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 may be flat. With this shape of the tab main body 10A, the connecting portion 13A can be provided simply by forming a hole H1 in the tab main body 10A, and the tab main body 10A can function as a fuse.

[0045] In a more specific embodiment of the tab main body, the outer edges E3 of the connecting portions 13A may be continuous with both outer edges E1 of the first tab portion 11A, and the outer edges E3 of the connecting portions 13A may be continuous with both outer edges E2 of the second tab portion 12A. In other words, the number of connecting portions 13A provided on the tab main body 10A may be at least two. With this configuration, the connecting portions 13A are connected to the first tab portion 11A and the second tab portion 12A at both ends, making the tab 10A resistant to twisting and less likely to break even if an external force is applied to the tab during normal use.

[0046] In a more specific embodiment of the tab body, the connecting portion 13A may have a dimension in the X direction that increases toward the first tab portion 11A and a dimension in the X direction that increases toward the second tab portion 12A. In other words, the connecting portion 13A may have a dimension in the X direction that gradually decreases toward the position where the overcurrent flows and melts. This configuration increases the electrical resistance near the melt-cut position of the connecting portion 13A, thereby promoting heat generation. This also increases the expansion of the thermal expansion member 20A that contacts the melt-cut position. This increases the thermal expansion of the thermal expansion member 20A near the melt-cut position, further separating the first tab portion 11A and the second tab portion 12A, and more effectively prevents re-contact between the first tab portion 11A and the second tab portion 12A.

[0047] [Tab of the second embodiment] Next, a tab 1B of the second embodiment will be described with reference to Figures 8 to 10B. In describing the tab 1B of the second embodiment, explanations of points common to the explanation in the above section [Tab of the first embodiment] will be omitted as appropriate. In other words, the following explanation will focus on points that are different from the explanation in the above section [Tab of the first embodiment].

[0048] 8, the tab 1B of the second embodiment may have a first bent portion F1 bent in the Z direction at the Y-direction end of the first tab portion 11B on the connecting portion 13B side and brought into contact with a Y-contact surface BY on one side of a thermal expansion member 20B (described later). Also, a second bent portion F2 bent in the Z direction at the Y-direction end of the second tab portion 12B on the connecting portion 13B side and brought into contact with a Y-contact surface BY on the other side of the thermal expansion member 20B (described later).

[0049] The thermal expansion member 20B of the second embodiment has a polygonal prism shape in a plan view, as shown in Fig. 8. As shown in Fig. 8, the thermal expansion member 20B has Y contact surfaces BY that contact the first bent portion F1 and the second bent portion F2, and may further have an X contact surface BX that contacts the connecting portion 13B.

[0050] When an overcurrent flows in the tab 1B of the second embodiment (see FIGS. 8 and 10A) and melts the connection portion 13B, heat caused by the overcurrent propagates to the thermal expansion member 20B, causing the thermal expansion member 20B to expand (see FIG. 10B). Specifically, stress in the X direction is applied to the connection portion 13B by the X contact surface BX of the thermal expansion member 20B, separating the first tab portion 11B and the second tab portion 12B in the X direction. More specifically, stress in the +X direction is applied to the connection portion 13B on the +X direction side shown in FIG. 8, and stress in the −X direction is applied to the connection portion 13B on the −X direction side shown in FIG. 8, separating the first tab portion 11B and the second tab portion 12B. Furthermore, the Y contact surface BY of the thermal expansion member 20B applies stress in the Y direction to the first bent portion F1 and the second bent portion F2, respectively, separating the first tab portion 11B and the second tab portion 12B in the Y direction. More specifically, stress in the -Y direction is applied to the first bent portion F1, and stress in the +Y direction is applied to the second bent portion F2, separating the first tab portion 11B and the second tab portion 12B.

[0051] Even in the tab 1B of the second embodiment, the thermal expansion member 20B has an X contact surface BX and a Y contact surface BY, so that stress can be applied in at least two directions, unlike the prior art technical concept of elastically deforming in one direction. Therefore, even if an overcurrent flows and the connection portion 13B melts, it is possible to more effectively prevent the melted portion from coming into contact again.

[0052] In a preferred embodiment of the first bent portion F1 and the second bent portion F2, the bend angle θ of the first bent portion F1 and the second bent portion F2 may be greater than 90° and less than 180° (see FIG. 10A ). The bend angle in this specification refers to the obtuse angle when the first bent portion F1 and the second bent portion F2 are bent. When the bend 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 receive stress in the Z direction from the thermal expansion member 20B. As described above, the tab main body 10B receives stress in the Z direction from the thermal expansion member 20B in addition to stress in the X direction from the X contact surface BX and stress in the Y direction from the Y contact surface BY, which further prevents re-contact at the blown point.

[0053] In a preferred embodiment of the tab 1B of the second embodiment, the connection portion 13B may include a first connection portion B1 connecting to the first tab portion 11B, a second connection portion B2 connecting to the second tab portion 12B, and a third connection portion B3 connecting the first connection portion B1 and the second connection portion B2, as shown in FIG. 9 . The first connection portion B1 may have a tapered portion whose X-direction dimension decreases toward the third connection portion B3, and the second connection portion B2 may have a tapered portion whose X-direction dimension decreases toward the third connection portion B3. With this configuration, the X-direction dimensions of the first connection portion B1 and the second connection portion B2 gradually decrease toward the location where an overcurrent flows and melts down. This increases the electrical resistance near the meltdown location of the connection portion 13B, thereby promoting heat generation. This increases the expansion of the thermal expansion member 20B, which is in contact with the third connection portion B3, which has high electrical resistance. This increases the thermal expansion of the thermal expansion member 20B near the blowout position, further separating the first tab portion 11B and the second tab portion 12B, and more effectively preventing re-contact between the first tab portion 11B and the second tab portion 12B.

[0054] As an example of a configuration for realizing the first connection portion B1, the second connection portion B2, and the third connection portion B3, as shown in FIG. 9 , the tab main body 10B may have a hole H2, and the connection portion 13B may be disposed outside the hole H2. The shape of the hole H2 may have a trapezoidal shape corresponding to the first connection portion B1, the second connection portion B2, and the third connection portion B3 when viewed along the Z direction. With this configuration, the hole H2 has a portion that elongates the third connection portion B3, which has high electrical resistance, thereby further enhancing the expansion of the thermal expansion member 20B that contacts the third connection portion B3. This further enhances the thermal expansion of the thermal expansion member 20B near the blowout position, further separating the first tab portion 11B and the second tab portion 12B, and more effectively preventing re-contact between the first tab portion 11B and the second tab portion 12B.

[0055] Furthermore, the thermal expansion member 20B has a shape corresponding to the shape of the hole H2, and the thermal expansion member 20B may be fitted into the hole H2. According to this embodiment, since the thermal expansion member 20B is in contact with the hole H2, the heat generated at the fusing position can be appropriately transmitted to the thermal expansion member 20B.

[0056] [Third embodiment tab] Next, a tab 1C of a third embodiment will be described with reference to Figures 11A and 11B. In describing the tab 1C of the third embodiment, the description of points common to the description in the above section [Tab of the Second Embodiment] will be omitted as appropriate. In other words, the following description will focus on points that are different from the description in the above section [Tab of the Second Embodiment].

[0057] As shown in Figures 11A and 11B, the tab 1C of the third embodiment may have a first hook portion F3 at the Z-direction end of the first bent portion F1 that contacts the Z-contact surface CZ of the thermal expansion member 20C described later, and a second hook portion F4 at the Z-direction end of the second bent portion F2 that contacts the Z-contact surface CZ of the thermal expansion member 20C.

[0058] The thermal expansion member 20C of the third embodiment may have a Z contact surface CZ that contacts the first hook portion F3 and the second hook portion F4, respectively (see FIG. 11B). Furthermore, as described in [Tab of the second embodiment], the thermal expansion member of the third embodiment may have a Y contact surface CY that contacts the first bent portion F1 and the second bent portion F2, respectively, and may further have an X contact surface CX that contacts the connecting portion 13C.

[0059] In the tab 1C of the third embodiment, the thermal expansion member 20C has a Z contact surface CZ as well as an X contact surface CX and a Y contact surface CY, which allows stress to act in three directions, unlike the prior art technical concept of elastically deforming in one direction. Therefore, even if an overcurrent flows and melts the connection portion 13C, it is possible to more effectively prevent the melted portion from re-contacting.

[0060] [Tab of Fourth Embodiment and Battery Module Including Tab of Fourth Embodiment] Next, a tab 1D of the fourth embodiment and a battery module BM including the tab 1D of the fourth embodiment will be described with reference to FIGS. 12 to 14B. In describing the tab 1D of the fourth embodiment, explanations of points common to the explanation in the above section [Tab of the first embodiment] will be omitted as appropriate. In describing the battery module BM including the tab 1D of the fourth embodiment, explanations of points common to the explanation in the above section [Battery module] will be omitted as appropriate. The following description will focus on points that differ from the above explanations.

[0061] The tab 1D of the fourth embodiment may be provided with a third bent portion F5 (see FIG. 12) on one side in the X direction (i.e., the +X direction side) of the first tab portion 11D, which is in contact with an X contact surface (first X contact surface DX1) on one side of a thermal expansion member 20D described later, and a fourth bent portion F6 (see FIG. 12) on the other side in the X direction (i.e., the −X direction side) of the second tab portion 12D, which is in contact with an X contact surface (second X contact surface DX2) on the other side of the thermal expansion member 20D described later.

[0062] Furthermore, the third bent portion F5 may extend in the -Z direction from the first tab portion 11D as shown in FIG. 12, and the fourth bent portion F6 may extend in the -Z direction from the second tab portion 12D as shown in FIG. 12.

[0063] Furthermore, the tab main body 10D of the fourth embodiment may not have a hole H1 like the tab main body 10A of the first embodiment, and the first tab portion 11D and the second tab portion 12D may be connected by at least one connecting portion 13D.

[0064] The thermal expansion member 20D of the fourth embodiment is not provided with the protrusions 22A that are provided in the thermal expansion member 20A of the first embodiment. Fig. 14 showing an example has a polygonal prism shape (quadratic prism shape) in plan view.

[0065] Furthermore, the thermal expansion member 20D of the fourth embodiment may have a first X contact surface DX1 (see FIG. 13) that contacts the above-mentioned third bent portion F5, and a second X contact surface DX2 (see FIG. 13) that contacts the above-mentioned fourth bent portion F6 and faces the first X contact surface DX1. Furthermore, the thermal expansion member 20D of the fourth embodiment may have a Z contact surface DZ (see FIG. 13) that contacts the tab main body 10D.

[0066] When an overcurrent flows in the tab 1D of the fourth embodiment (see FIG. 13) and melts the connection portion 13D, heat caused by the overcurrent propagates to the thermal expansion member 20D, causing the thermal expansion member 20D to expand (see FIGS. 14A and 14B). Specifically, as shown in FIG. 14A, the first X-contact surface DX1 of the thermal expansion member 20D expands, and a third bent portion F5 in contact with the first X-contact surface DX1 generates stress that moves the first tab portion 11D in the +X direction. Furthermore, the second X-contact surface DX2 of the thermal expansion member 20D expands, and a fourth bent portion F6 in contact with the second X-contact surface DX2 generates stress that moves the second tab portion 12D in the −X direction. This separates the first tab portion 11D and the second tab portion 12D from each other, effectively preventing re-contact between the first tab portion 11D and the second tab portion 12D. Furthermore, as shown in Figure 14B, the Z contact surface DZ of the thermal expansion member 20D expands in the +Z direction, causing the first tab portion 11D and the second tab portion 12D to warp and bend, and stress acts to further separate the first tab portion 11D and the second tab portion 12D.

[0067] Therefore, unlike the prior art where the tab 1D is elastically deformed in one direction, the tab 1D of the fourth embodiment can apply stress in at least two directions, which makes it possible to more effectively prevent re-contact at the fused portion even if an overcurrent flows and melts the connection portion 13D.

[0068] In a preferred embodiment of connection portion 13D, there may be one connection portion 13D, as shown in Fig. 13. Therefore, by fusing one connection portion 13D, it is possible to preferably electrically disconnect first tab portion 11D and second tab portion 12D.

[0069] Furthermore, in an embodiment in which there is one connecting portion 13D, the connecting portion 13D may connect the first tab portion 11D and the second tab portion 12D at the center in the X direction of the first tab portion 11D and / or the second tab portion 12D, as shown in Fig. 13. When the connecting portion 13D is positioned at the center in the X direction, as shown in Fig. 14A, the expansion of the thermal expansion member 20D can cause the first tab portion 11D to move and rotate in the +X direction, and the second tab portion 12D to move and rotate in the -X direction, thereby appropriately separating the first tab portion 11D and the second tab portion 12D in the X direction.

[0070] To more appropriately separate the first tab portion 11D and the second tab portion 12D, a battery module BM including the tab 1D of the fourth embodiment may be provided with a structure that promotes separation. For example, as shown in FIG. 12 , a battery holder HD that accommodates a battery CB may be provided with a first wall portion W1 facing the X contact surface (first X contact surface DX1) on one side of the thermal expansion member 20D and adjacent to the third bent portion F5, and a second wall portion W2 facing the X contact surface (second X contact surface DX2) on the other side of the thermal expansion member 20D and adjacent to the fourth bent portion F6. This structure suppresses expansion of the portion of the thermal expansion member 20D facing the second wall portion W2 and promotes expansion of the portion of the thermal expansion member 20D located on the third bent portion F5 side. This further increases the stress acting in the +X direction from the thermal expansion member 20D to the third bent portion F5. Therefore, the thermal expansion member 20D can further generate stress that moves the first tab portion 11D in the +X direction. Similarly, expansion of the portion facing the first wall portion W1 is suppressed, and expansion of the portion of the thermal expansion member 20D located on the fourth bent portion F6 side is promoted, thereby further generating stress that acts from the thermal expansion member 20D to the fourth bent portion F6 in the -X direction. Therefore, the thermal expansion member 20D can further generate stress that moves the second tab portion 12D in the -X direction.

[0071] Furthermore, in the battery holder HD, the first wall W1 may face the fourth bent portion F6, and the second wall W2 may face the third bent portion F5. In this specification, "facing" refers not only to mutually facing members completely overlapping each other, but also to mutually facing members only partially overlapping each other. This configuration allows the first wall W1 and the second wall W2 to suppress expansion of the thermal expansion member 20D and apply stress to the third bent portion F5 and the fourth bent portion F6 that separates the first tab portion 11D and the second tab portion 12D from each other.

[0072] In a further preferred embodiment, the size of the first wall portion W1 may be equal to the size of the third bent portion F5, and the size of the second wall portion W2 may be equal to the size of the fourth bent portion F6. With this relationship, it is possible to optimize the balance between the suppression of expansion of the thermal expansion member 20D by the first wall portion W1 and the second wall portion W2 and the application of stress that separates the first tab portion 11D and the second tab portion 12D by the third bent portion F5 and the fourth bent portion F6.

[0073] It should be noted that the embodiments disclosed herein are illustrative in all respects and are not intended to be limiting. Therefore, the technical scope of the present disclosure should not be interpreted solely by the above-described embodiments, but should be defined based on the claims. The technical scope of the present disclosure also includes all modifications within the scope and meaning equivalent to the claims.

[0074] Aspects of the tab, battery module, and battery pack of the present disclosure are as follows. <1> a tab main body including a first tab portion, a second tab portion, and a connection portion connecting the first tab portion and the second tab portion; a thermal expansion member in contact with at least the connection portion, a direction in which the first tab portion and the second tab portion are aligned via a connection portion is defined as a Y direction, a thickness direction of the tab main body is defined as a Z direction, and a direction perpendicular to each of the Y direction and the Z direction is defined as an X direction; a dimension of the connection portion in the X direction is smaller than a dimension of the first tab portion in the X direction and a dimension of the second tab portion in the X direction, The thermal expansion member has at least two of an X contact surface that comes into contact with the tab main body in the X direction, a Y contact surface that comes into contact with the tab main body in the Y direction, and a Z contact surface that comes into contact with the tab main body in the Z direction. <2> the thermal expansion member has a protrusion that protrudes in the Z direction from the Z contact surface, The protrusion is provided with the X contact surface and / or the Y contact surface. <1> Tab described in. <3> The tab body has a hole, and the connection portion is disposed outside the hole. The protrusion is inserted into the hole. <2> Tab described in. <4> When viewed along the Z direction, the protrusion is fitted into the hole. <3> Tab described in. <5> a maximum dimension of the protrusion in the Z direction being equal to or greater than a thickness dimension of the tab body; <2> ~ <4> Tabs listed in one of the following. <6> The maximum dimension of the hole in the X direction is equal to or greater than the dimension of the connection portion in the X direction. <3> or <3> Quote <4> or <5> Tabs listed in one of the following. <7> a first bent portion bent toward the Z direction at an end of the first tab portion on the connection portion side and in contact with the Y contact surface on one side of the thermal expansion member; a second bent portion bent toward the Z direction at an end of the second tab portion on the Y direction side of the connection portion and in contact with the Y contact surface on the other side of the thermal expansion member; <1> ~ <6> Tabs listed in one of the following. <8> a first hook portion that contacts the Z contact surface of the thermal expansion member is provided at an end of the first bent portion in the Z direction; A second hook portion is provided at the Z-direction end of the second bent portion, and the second hook portion is in contact with the Z-contact surface of the thermal expansion member. <7> Tab described in. <9> The connection portion is a first connection portion connected to the first tab portion, a second connection portion connected to the second tab portion, and a third connection portion connecting the first connection portion and the second connection portion, the first connection portion includes a tapered portion whose dimension in the X direction decreases toward the third connection portion; The second connection portion has a tapered portion whose dimension in the X direction decreases toward the third connection portion. <1> ~ <8> Tabs listed in one of the following. <10> The tab body has a hole, and the connection portion is disposed outside the hole. the shape of the hole has trapezoidal portions corresponding to the first connection portion, the second connection portion, and the third connection portion when viewed along the Z direction; The thermal expansion member is fitted into the hole. <9> Tab described in. <11> a third bent portion that comes into contact with the X contact surface on one side of the thermal expansion member is provided on one side of the first tab portion in the X direction; a fourth bent portion that contacts the X contact surface on the other side of the thermal expansion member is provided on the other side of the second tab portion in the X direction; <1> ~ <10> Tabs listed in one of the following. <12> <1> ~ <11> a tab described in any one of the following: a battery cell electrically connected to the tab; A battery module comprising the battery cell and a battery holder that houses the battery cell. <13> <11> and the tabs described in a battery cell electrically connected to the tab; a battery holder that houses the battery cell; the battery holder includes 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. [Industrial Applicability]

[0075] The present disclosure can be suitably used as a tab, a battery module, and a battery pack that prevent re-contact at the blown point even if an overcurrent flows and the fuse blows. [Explanation of symbols]

[0076] Tabs 1, 1A, 1B, 1C, 1D 10, 10A, 10B, 10C, 10D Tab body 11A, 11B, 11C, 11D First tab part 11I insertion section 12A, 12B, 12C, 12D Second tab 12T terminal connection 13A, 13B, 13C, 13D Connections 20A, 20B, 20C, 20D Thermal expansion members 21A, 21B base part 22A,22B Protrusion AXY side BX,CX,DX X contact surface DX1 1st X contact surface DX2 2nd X contact surface CY, DY Y contact surface AZ,BZ,CZ,DZ Z contact surface F1 1st bend F2 2nd bend F3 First hook part F4 Second hook part F5 3rd bend F6 4th bend BM battery module BP battery pack C1 First connection point C2 Second connection point C3 Third connection point CB battery CN Connector CS Case CS1 Case 1 CS2 Second Case E1 lateral border E2 lateral border E3 lateral border H1,H2 hole HD Battery Holder IH insertion hole L1 dimension L2 dimension L3 dimension L4 Maximum dimension NT negative terminal OP opening PT positive terminal SB control board T1 dimension T2 dimensions W1 First wall W2 Second wall θ bending angle

Claims

1. 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; a thermal expansion member in contact with at least the connection portion, a direction in which the first tab portion and the second tab portion are aligned via a connection portion is defined as a Y direction, a thickness direction of the tab main body is defined as a Z direction, and a direction perpendicular to each of the Y direction and the Z direction is defined as an X direction; a dimension of the connection portion in the X direction is smaller than a dimension of the first tab portion in the X direction and a dimension of the second tab portion in the X direction, the thermal expansion member has at least two of an X contact surface that comes into contact with the tab main body in the X direction, a Y contact surface that comes into contact with the tab main body in the Y direction, and a Z contact surface that comes into contact with the tab main body in the Z direction.

2. the thermal expansion member includes a protrusion that protrudes in the Z direction from the Z contact surface, The tab of claim 1 , wherein the protrusion is provided with the X contact surface and / or the Y contact surface.

3. The tab body has a hole, and the connection portion is disposed outside the hole. The tab according to claim 2 , wherein the protrusion is inserted into the hole.

4. The tab according to claim 3 , wherein the protrusion is fitted into the hole when viewed along the Z direction.

5. The tab according to claim 2 , wherein the maximum dimension of the protrusion in the Z direction is equal to or greater than the thickness dimension of the tab body.

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

7. a first bent portion bent toward the Z direction at an end of the first tab portion on the connection portion side and in contact with the Y contact surface on one side of the thermal expansion member; The tab according to claim 1, wherein the Y-direction end of the second tab portion on the connection portion side is provided with a second bent portion that is bent toward the Z direction and contacts the Y contact surface on the other side of the thermal expansion member.

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

9. The connection portion is a first connection portion connected to the first tab portion, a second connection portion connected to the second tab portion, and a third connection portion connecting the first connection portion and the second connection portion, the first connection portion includes a tapered portion whose dimension in the X direction decreases toward the third connection portion, The tab according to claim 1 , wherein the second connection portion has a tapered portion whose dimension in the X direction decreases toward the third connection portion.

10. The tab body has a hole, and the connection portion is disposed outside the hole. the shape of the hole has trapezoidal portions corresponding to the first connection portion, the second connection portion, and the third connection portion when viewed along the Z direction; The tab of claim 9 , wherein the thermal expansion member is mated with the hole.

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

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

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

Images