Battery Module

Abstract

To provide a battery module with a high handling ability of an insulation member assembled between a plurality of battery cells.SOLUTION: An insulation member contains: a base; and a plurality of convex parts that are projected in a first direction from the base, and contacts to at least one of a plurality of battery cells. Each convex part contains: a first convex part; a second convex part that is aligned with the first convex part along a second direction orthogonal to the first direction; and a third convex part that is aligned with the first convex part along a third direction orthogonal to the first direction and crossing the second direction. A rib projected in the first direction from the base is provided between the first convex part and the second convex part, and between the first convex part and the third convex part. In a state where the insulation member is removed from the battery module, the width of the rib is narrower than that of the convex part.SELECTED DRAWING: Figure 3

Description

[Technical field]

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

[0002] Patent Document 1 discloses a cushioning sheet for a battery module that is designed to elastically support battery cells during charging and to reliably apply a reaction force during discharging. This cushioning sheet includes a base portion and elastic protrusions that protrude from the base portion toward the battery cells.

[0003] Patent Document 2 discloses an insulating plate for a secondary battery that includes a body portion and a protrusion that is bonded to the upper surface of the body portion and protrudes upward.

[0004] Examples of structures similar to those described above that are used in fields other than batteries include those described in Patent Documents 3 and 4. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-004556 A [Patent Document 2] Special Publication No. 2022-521195 [Patent Document 3] JP 2013-215312 A [Patent Document 4] JP 2000-093487 A Summary of the Invention [Problem to be solved by the invention]

[0006] From the viewpoint of miniaturizing the battery module, it is desirable for the thickness of the above-mentioned buffer sheet to be thin. On the other hand, from the viewpoint of reliably supporting the battery cells, it is desirable for the height of the elastic protrusion to be high. To achieve both of these demands, the base portion is formed thin. However, if the base portion is too thin, the handling properties of the buffer sheet may deteriorate when it is assembled between multiple battery cells.

[0007] An object of the present technology is to provide a battery module in which insulating members to be assembled between a plurality of battery cells are easy to handle. [Means for solving the problem]

[0008] The present technology provides the following battery module.

[0009] [1] A battery module comprising a plurality of battery cells arranged in a first direction and an insulating member provided between the plurality of battery cells, wherein the insulating member includes a base and a plurality of convex portions protruding from the base in the first direction and abutting at least one of the plurality of battery cells, the convex portions including a first convex portion, a second convex portion aligned with the first convex portion along a second direction perpendicular to the first direction, and a third convex portion aligned with the first convex portion along a third direction perpendicular to the first direction and intersecting the second direction, wherein ribs protruding from the base in the first direction are provided between the first convex portion and the second convex portion and between the first convex portion and the third convex portion, and wherein when the insulating member is removed from the battery module, a width of the rib is narrower than a width of the convex portions.

[0010] [2] The battery module according to [1], wherein the rib is formed so as to connect the first convex portion and the second convex portion, and the first convex portion and the third convex portion.

[0011] [3] The battery module according to [1] or [2], wherein when the insulating member is removed from the battery module, the protruding height of the rib is lower than the protruding height of the convex portion.

[0012] [4] A battery module described in any one of [1] to [3], wherein the base has a first surface and a second surface opposing each other in a first direction, the rib includes a first rib formed on the first surface and a second rib formed on the second surface, and the first rib and the second rib are formed at different positions from each other in the second direction or the third direction.

[0013] [5] The battery module according to any one of [1] to [4], wherein the insulating member includes a material selected from the group consisting of ethylene propylene rubber, urethane rubber, silicone rubber, and fluororubber.

[0014] [6] A battery module described in any one of [1] to [5], wherein when the insulating member is removed from the battery module, the height and width of the rib are approximately constant between the first convex portion and the second convex portion, or between the first convex portion and the third convex portion, and the height of the rib is at least twice the width of the rib.

[0015] [7] A battery module described in any one of [1] to [5], wherein when the insulating member is removed from the battery module, the width of the rib tapers from the tip of the rib toward the base between the first convex portion and the second convex portion, or between the first convex portion and the third convex portion. Effect of the Invention

[0016] According to the present technology, by extending the ribs in two directions (second direction and third direction) perpendicular to the arrangement direction (first direction) of the multiple battery cells, the rigidity of the base can be improved and the handling of the insulating member during assembly can be improved. [Brief description of the drawings]

[0017] [Figure 1] FIG. 2 is a perspective view of a battery module. [Diagram 2] FIG. 2 is a perspective view showing a battery cell. [Diagram 3] FIG. [Figure 4] 4 is a cross-sectional view taken along the line A1-A1 in FIG. [Diagram 5] 4 is a cross-sectional view taken along line A2-A2 in FIG. [Figure 6] 4 is a cross-sectional view taken along line A3-A3 in FIG. [Figure 7] 4 is a cross-sectional view of the insulating member according to the first modified example taken along line A1-A1 in FIG. 3. [Figure 8] 4 is a cross-sectional view of an insulating member according to a second modified example taken along line A1-A1 in FIG. 3. [Figure 9] 4 is a cross-sectional view of an insulating member according to a second modified example taken along line A2-A2 in FIG. 3. [Figure 10] 4 is a cross-sectional view of an insulating member according to a second modified example taken along line A3-A3 in FIG. 3. [Figure 11] FIG. 13 is a plan view of an insulating member according to a third modified example. [Figure 12] FIG. 13 is a plan view of an insulating member according to a fourth modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, embodiments of the present technology will be described. Note that the same or corresponding parts are denoted by the same reference characters, and description thereof will not be repeated.

[0019] In the embodiments described below, when referring to the number, amount, etc., the scope of the present technology is not necessarily limited to the number, amount, etc., unless otherwise specified. In addition, in the following embodiments, each component is not necessarily essential to the present technology, unless otherwise specified. In addition, the present technology is not necessarily limited to those that achieve all of the effects and advantages mentioned in the present embodiment.

[0020] In this specification, the words "comprise", "include" and "have" are open-ended, i.e., when a certain configuration is included, other configurations may or may not be included.

[0021] Furthermore, when geometric terms and terms expressing positional and directional relationships, such as "parallel," "orthogonal," "45° diagonal," "coaxial," and "along" are used in this specification, these terms allow for manufacturing errors and slight variations. When terms expressing relative positional relationships, such as "upper side" and "lower side," are used in this specification, these terms are used to indicate relative positional relationships in one state, and the relative positional relationships can be inverted or rotated to any angle depending on the installation direction of each mechanism (for example, by turning the entire mechanism upside down).

[0022] In this specification, "battery" is not limited to lithium-ion batteries, but may include other batteries such as nickel-metal hydride batteries and sodium-ion batteries.

[0023] In this specification, the term "battery cell" is not necessarily limited to a rectangular type, and may include cells of other shapes, such as a cylindrical type, a pouch type, and a blade type. The "battery cell" can be mounted in hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and battery electric vehicles (BEVs). However, the use of the "battery cell" is not limited to in-vehicle use.

[0024] Fig. 1 is a perspective view of a battery module according to the present embodiment. As shown in Fig. 1, the battery module 1 includes battery cells 100 and insulating members 200 (inter-cell separators). The battery cells 100 and the insulating members 200 are arranged alternately along the Y-axis direction (first direction).

[0025] The battery cells 100 are rectangular battery cells, and a plurality of battery cells 100 are provided along the Y-axis direction. The plurality of battery cells 100 are electrically connected to each other via bus bars (not shown).

[0026] The insulating member 200 is provided between multiple battery cells 100. The insulating member 200 prevents unintended electrical conduction between adjacent battery cells 100. The insulating member 200 ensures electrical insulation between adjacent battery cells 100.

[0027] Fig. 2 is a perspective view showing the battery cell 100. As shown in Fig. 2, the battery cell 100 has a rectangular shape. The battery cell 100 has an electrode terminal 110, a housing 120, and a gas release valve .

[0028] The electrode terminal 110 is formed on the housing 120. The electrode terminal 110 has a positive electrode terminal 111 and a negative electrode terminal 112 aligned along an X-axis direction (second direction) perpendicular to a Y-axis direction (first direction). The positive electrode terminal 111 and the negative electrode terminal 112 are provided apart from each other in the X-axis direction.

[0029] The housing 120 has a rectangular parallelepiped shape and forms the external appearance of the battery cell 100. The housing 120 includes a case body 120A that contains an electrode body and an electrolyte (not shown), and a sealing plate 120B that seals an opening of the case body 120A. The sealing plate 120B is joined to the case body 120A by welding.

[0030] The housing 120 has an upper surface 121, a lower surface 122, a first side surface 123, a second side surface 124, and two third side surfaces 125.

[0031] The upper surface 121 is a plane perpendicular to the Z-axis direction (third direction) perpendicular to the Y-axis direction and the X-axis direction. The electrode terminals 110 are disposed on the upper surface 121. The lower surface 122 faces the upper surface 121 along the Z-axis direction.

[0032] Each of the first side surface 123 and the second side surface 124 is formed of a plane perpendicular to the Y-axis direction. Each of the first side surface 123 and the second side surface 124 has the largest area among the multiple side surfaces of the housing 120. Each of the first side surface 123 and the second side surface 124 has a rectangular shape when viewed in the Y-axis direction. Each of the first side surface 123 and the second side surface 124 has a rectangular shape with the X-axis direction being the long side direction and the Z-axis direction being the short side direction when viewed in the Y-axis direction.

[0033] The multiple battery cells 100 are stacked such that the first side surfaces 123 and the second side surfaces 124 of the battery cells 100 adjacent to each other in the Y-axis direction face each other. As a result, the positive electrode terminals 111 and the negative electrode terminals 112 are arranged alternately in the Y-axis direction in which the multiple battery cells 100 are stacked.

[0034] Gas exhaust valve 130 is provided on top surface 121. When the temperature of battery cell 100 rises (thermal runaway) and the internal pressure of housing 120 exceeds a predetermined value due to gas generated inside housing 120, gas exhaust valve 130 exhausts the gas to the outside of housing 120.

[0035] Fig. 3 is a plan view of the insulating member 200, and Fig. 4 to Fig. 6 are cross-sectional views taken along lines A1-A1, A2-A2, and A3-A3, respectively, in Fig. 3. Note that Figs. 3 to 6 and Figs. 7 to 12, which will be described later, show the insulating member 200 in a state where it has been removed from the battery module 1.

[0036] 3 to 6, the insulating member 200 includes a base 210, a plurality of protrusions 220 protruding from the base 210 in the Y-axis direction, and a rib 230 protruding from the base 210 in the Y-axis direction so as to connect between the plurality of protrusions 220. The insulating member 200 including the base 210, the protrusions 220, and the rib 230 may be formed by integral molding.

[0037] The insulating member 200 may be made of an electrically insulating and elastic material, such as ethylene propylene rubber (EPDM), urethane rubber (U), silicone rubber (Si), or fluororubber.

[0038] In the example shown in FIG. 3, the convex portions 220 are arranged in a matrix such that seven convex portions (221A to 227A, 221B to 227B, 221C to 227C) are evenly aligned in the X-axis direction, and three convex portions (221A to 221C, 222A to 222C, 223A to 223C, 224A to 224C, 225A to 225C, 226A to 226C, 227A to 227C) are evenly aligned in the Z-axis direction.

[0039] However, the number, shape (rectangle, other polygon, circle, etc.), protruding height, arrangement (arrangement direction, interval, etc.), and size of the multiple protruding parts 220 can be changed as appropriate. Among the multiple protruding parts 220, some of the protruding parts 220 may have different shapes, protruding heights, arrangements, and sizes.

[0040] The rib 230 is provided between the plurality of protruding portions 220. In the example of Fig. 3, the rib 230 is formed so as to connect the plurality of protruding portions 220. For example, the rib 230 extending in the X-axis direction is formed so as to connect the protruding portion 221A (first protruding portion) and the protruding portion 222A (second protruding portion) arranged in the X-axis direction, and the rib 230 extending in the Z-axis direction is formed so as to connect the protruding portion 221A (first protruding portion) and the protruding portion 221B (third protruding portion) arranged in the Z-axis direction. The rib 230 extending in the X-axis direction or the Z-axis direction is also provided between the other protruding portions 220 in the same manner as above.

[0041] As shown in FIG. 3, when the insulating member 200 is removed from the battery module 1, the width (B) of the rib 230 is narrower than the width (C) of the protruding portion 220. As shown in FIG.

[0042] As shown in FIGS. 4 to 6, when the insulating member 200 is removed from the battery module 1, the protruding height (H) of the rib 230 is smaller than the protruding height of the convex portion 220. As shown in FIG.

[0043] 5 and 6, the rib 230 has a rectangular cross-sectional shape when viewed in the extending direction (X-axis direction and Z-axis direction). The height and width of the rib 230 are constant between the multiple protrusions 220. In this case, it is preferable that the height (H) of the rib 230 is about twice or more the width (B) (H / B≧2).

[0044] A thin insulating member 200 is desirable from the standpoint of miniaturizing the battery module 1. However, if the base 210 is too thin, the handling of the insulating member 200 may deteriorate when the insulating member 200 is assembled between multiple battery cells 100.

[0045] In contrast, in the battery module 1 according to the present embodiment, the ribs 230 extend in two directions, the X-axis direction and the Z-axis direction, and connect the multiple protrusions 220 on the base 210, thereby improving the rigidity of the base 210. As a result, the handleability of the insulating member 200 when assembled to the battery module 1 can be improved. In addition, since the base 210 can be made thin (for example, to a thickness of about 0.5 mm or less) while ensuring a predetermined rigidity, the protruding height of the protrusions 220 can be set high without making the insulating member 200 excessively thick, and therefore the dimensional absorbency (error absorbency or deformation absorbency) due to the elastic deformation of the protrusions 220 can be improved.

[0046] Furthermore, by making the protruding height (H) of the ribs 230 lower than the protruding height of the convex portions 220, the space surrounded by the convex portions 220 and the ribs 230 is not blocked. Therefore, the elasticity of the convex portions 220 is prevented from fluctuating due to the air pressure in the blocked space, and the elastic constant of the convex portions 220 can be stabilized.

[0047] Fig. 7 is a cross-sectional view of the insulating member according to the first modified example taken along line A1-A1 in Fig. 3. In the example of Fig. 7, protrusions 220 are formed on both sides of insulating member 200. That is, rib 230 includes rib 231 (first rib) formed on the front surface (first surface) of base 210 and rib 232 (second rib) formed on the back surface (second surface).

[0048] As in the example of FIG. 7, by forming the convex portions 220 on both sides of the insulating member 200, the dimensional adaptability of the insulating member 200 due to the elastic deformation of the convex portions can be improved.

[0049] 8 to 10 are cross-sectional views taken along the lines A1-A1, A2-A2, and A3-A3 in FIG. 3 of the insulating member 200 according to the second modified example. In the example of FIGS. 8 to 10, when the insulating member 200 is removed from the battery module 1, the width of the rib 230 tapers from the apex (tip) of the rib 230 toward the base 210. In the example of FIGS. 8 to 10, a tapered cross section is formed that is asymmetrical (asymmetrical with respect to the Y-axis direction) when viewed from the extension direction of the rib 230 (the X-axis direction and the Z-axis direction).

[0050] As in the examples of Figs. 8 to 10, the cross section of the rib 230 is formed into a tapered triangular shape that widens, so that the top of the rib 230 can be formed thin. Also, by making the cross section of the rib 230 asymmetrical (asymmetrical with respect to the Y-axis) when viewed from the extension direction of the rib 230 (X-axis direction and Z-axis direction), the deformation direction of the rib 230 that deforms in accordance with the deformation of the protrusion 220 can be controlled. Specifically, the rib 230 can be made to easily collapse. As a result, the effect on the elastic properties of the protrusion 220 caused by the presence of the rib 230 can be reduced, so that the fluctuation of the elastic properties of the protrusion 220 can be suppressed.

[0051] The cross-sectional shape of the rib 230 is not limited to the above-mentioned rectangle or triangle, and may be, for example, a cross-sectional shape that includes a curve in part of the outline. Also, the rib 230 may have a shape that does not have a vertex at its tip (for example, the upper end is formed into a flat shape).

[0052] Next, third and fourth modified examples of the insulating member 200 will be described with reference to Figures 11 and 12. Specifically, further modified examples of the arrangement of the ribs 230 in the insulating member 200 will be described.

[0053] 11 and 12, rib 230 is formed such that rib 231 on the front surface of base 210 and rib 232 on the back surface of base 210 are formed at different positions in the X-axis direction or the Z-axis direction. As in the examples of Figures 11 and 12, the arrangement of rib 230 can be changed as appropriate.

[0054] In addition, when the handling ability of insulating member 200 is sufficient by forming protrusions 220 of different heights on both sides of insulating member 200 and providing ribs 230 on only one of the sides, ribs 230 can be formed on the side on which higher protrusions 220 are formed.

[0055] Although the embodiment of the present technology has been described above, the embodiment disclosed herein should be considered as illustrative and not restrictive in all respects. The scope of the present technology is defined by the claims, and it is intended to include all modifications within the scope and meaning equivalent to the claims. [Explanation of symbols]

[0056] 1 battery module, 100 battery cell, 110 electrode terminal, 111 positive electrode terminal, 112 negative electrode terminal, 120 housing, 120A case body, 120B sealing plate, 121 upper surface, 122 lower surface, 123 first side surface, 124 second side surface, 125 third side surface, 130 gas exhaust valve, 200 insulating member, 210 base, 220, 221A to 227A, 221B to 227B, 221C to 227C protrusions, 230, 231, 232 ribs.

Claims

1. A plurality of battery cells arranged in a first direction; an insulating member provided between the plurality of battery cells, the insulating member includes a base and a plurality of protrusions protruding from the base in the first direction and abutting against at least one of the plurality of battery cells; the protrusions include a first protrusion, a second protrusion aligned with the first protrusion along a second direction perpendicular to the first direction, and a third protrusion aligned with the first protrusion along a third direction perpendicular to the first direction and intersecting the second direction; a rib protruding from the base in the first direction is provided between the first convex portion and the second convex portion and between the first convex portion and the third convex portion; When the insulating member is removed from the battery module, a width of the rib is smaller than a width of the protrusion, A battery module, wherein when the insulating member is removed from the battery module, the cross-sectional shape of the rib is asymmetric with respect to the axis of the first direction when viewed from the extension direction of the rib extending in the second direction or the third direction.

2. The battery module according to claim 1 , wherein the rib is formed so as to connect the first convex portion and the second convex portion, and the first convex portion and the third convex portion.

3. 3. The battery module according to claim 1, wherein a protruding height of the rib is smaller than a protruding height of the convex portion when the insulating member is removed from the battery module.

4. the base has a first surface and a second surface opposed to each other in the first direction; the rib includes a first rib formed on the first surface and a second rib formed on the second surface; The battery module according to claim 1 , wherein the first rib and the second rib are formed at different positions from each other in the second direction or the third direction.

5. 3. The battery module according to claim 1, wherein the insulating member includes a material selected from the group consisting of ethylene propylene rubber, urethane rubber, silicone rubber, and fluororubber.

6. 3. The battery module of claim 1, wherein when the insulating member is removed from the battery module, the height and width of the rib are approximately constant between the first convex portion and the second convex portion, or between the first convex portion and the third convex portion, and the height of the rib is at least twice the width of the rib.

7. 3. The battery module according to claim 1, wherein when the insulating member is removed from the battery module, the width of the rib tapers from the tip of the rib toward the base between the first convex portion and the second convex portion, or between the first convex portion and the third convex portion.

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