Battery module

Abstract

Provided is a battery module which can be easily manufactured and in which there is reduced contact between an ejected substance that has been ejected from an abnormal battery where an abnormality occurred and a normal battery adjacent to the abnormal battery. A battery module BM according to the present disclosure comprises: a plurality of batteries BT that are each provided with an explosion-proof valve EV on the upper surface thereof and are arranged side by side in a first direction; a first heat-insulating plate HI1 that is disposed above the plurality of batteries BT; and second heat-insulating plates HI2 that are disposed between the plurality of batteries. The first heat-insulating plate HI1 is provided with a plurality of openings OP that are respectively provided at positions facing the explosion-proof valves EV and are arranged side by side in the first direction, and slits SL that are provided between the openings OP. The second heat-insulating plates HI2 are provided with body portions BP that face the batteries BT, and protruding portions PP that protrude from the body portions BP toward the first heat-insulating plate HI1. The protruding portions PP are inserted into the slits SL, and the protruding portions PP cover the openings OP.

Description

Battery module

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

[0002] Patent Document 1 discloses a battery module including a battery (2) and an insulating plate (4), in which the insulating plate (4) is provided on the side of the electrical connection assembly (3) that is closer to the upper case (12), and the insulating plate (4) has a plurality of pressure relief holes (41), each of which is provided in correspondence with an explosion-proof valve (21) of the battery (2) (see Figure 2 and paragraph

[0047] of Patent Document 1).

[0003] Furthermore, Patent Document 1 (see claim 4) discloses that a mounting hole (42) is provided in the heat insulating plate (4), a positioning pin (311) is installed in the electrical connection assembly (3), and the positioning pin (311) is fitted into the mounting hole (42) and then fixed in the mounting hole (42) by heat crimping.

[0004] Chinese Utility Model No. 218299959

[0005] The battery module described in Patent Document 1 uses mounting holes 42 and positioning pins 311 to secure the heat insulating plate 4, which poses a problem of difficulty in aligning all of the positioning pins 311 with the mounting holes 42. Furthermore, the process of fixing the positioning pins 311 to the mounting holes 42 by thermal caulking increases the number of steps, resulting in high manufacturing costs.

[0006] Furthermore, the ejected material from the battery 2 due to thermal runaway of the battery 2 could pass through the pressure relief hole 41 and also through the adjacent pressure relief hole 41, potentially causing gas and ejected material to flow into the normal battery 2. As a result, there was a risk of adversely affecting the normal battery 2.

[0007] The present disclosure has been made in light of this viewpoint, and a primary objective of the present disclosure is to provide a battery module that is easy to manufacture and that further reduces the likelihood that ejected material from an abnormal battery will come into contact with normal batteries adjacent to the abnormal battery.

[0008] The battery module of the present disclosure comprises: a plurality of batteries each having an explosion-proof valve on its upper surface and arranged in a line in a first direction; a first insulating plate arranged above the plurality of batteries; and a second insulating plate arranged between the plurality of batteries; the first insulating plate is provided at a position opposite the explosion-proof valve, and comprises a plurality of openings arranged in the first direction and slits provided between the openings; and the second insulating plate has a main body portion facing the batteries and a protrusion protruding from the main body portion toward the first insulating plate, the protrusion being inserted into the slit and covering the opening.

[0009] According to the present disclosure, manufacturing can be easily performed, and it is possible to further reduce the possibility that ejected material from an abnormal battery that has developed an abnormality will come into contact with a normal battery adjacent to the abnormal battery.

[0010] FIG. 1 is a perspective view of a battery module according to one embodiment. FIG. 2 is an exploded perspective view of a battery module according to one embodiment. FIG. 3 is a plan view of a first insulating plate. FIG. 4 is a front view of a second insulating plate. FIG. 5 is a front view of a battery. FIG. 6 is a schematic diagram showing the attachment state of the first insulating plate and the second insulating plate (a schematic diagram corresponding to the cross-sectional view taken along line VI-VI in FIG. 2). FIG. 7 is an enlarged schematic diagram of the dashed area in FIG. 6. FIG. 8 is a schematic diagram showing the state in which the protrusion in FIG. 7 is bent. FIG. 9 is a schematic diagram showing the state in which an abnormality has occurred in one battery provided in the battery module.

[0011] A 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 product.

[0012] As used herein, the term "plan view" refers to the state when an object (e.g., a battery module) is placed and viewed from directly above in the thickness (height) direction, and is synonymous with a plan view. For example, the term "plan view" refers to the state when viewed along the positive direction in the "Z direction" shown in FIG. 1 . As used herein, unless otherwise specified, the term "side view" refers to the state when an object (e.g., a battery module) is placed and viewed from the side perpendicular to the thickness (height) direction, and is synonymous with a side view. For example, the term "side view" refers to the state when viewed along the positive (or negative) direction in the "Y direction" shown in FIG. 1 . As used herein, the term "front view" refers to the state when an object (e.g., a battery module) is placed and viewed from the front perpendicular to the thickness (height) direction, and is synonymous with a front view. For example, the term "front view" refers to the state when viewed along the positive direction in the "X direction" shown in FIG. 1 . The "positive direction" mentioned above refers to the directions of the X, Y, and Z arrows shown in the drawings, and the "negative direction" refers to the direction opposite to the X, Y, and Z arrows shown in the drawings. The X, Y, and Z directions are perpendicular to each other.

[0013] [Configuration of Battery Module] The configuration of the battery module BM of the present disclosure will be described with reference to Figures 1 to 9. The battery module BM includes a battery BT, a first insulating plate HI1, and a second insulating plate HI2 (see Figures 1 and 2). The battery module BM may also include a tab assembly TA (see Figure 2) and a case CS (see Figures 1 and 2) that houses these components.

[0014] -Battery- The battery BT is intended to be a chemical battery that converts primarily chemical energy into direct current power through a chemical reaction. The batteries BT used in the battery module BM of this embodiment are housed in the case CS while arranged along a first direction (the Y direction in FIG. 2). Note that the example in FIG. 2 shows an embodiment in which nine batteries BT are arranged along the first direction. The shape of the battery BT is intended to be a rectangular parallelepiped battery, as exemplified in FIGS. 2 and 5. By using a rectangular parallelepiped battery BT, multiple batteries BT can be housed in the case CS in a juxtaposed state. Note that the shape of the battery BT may be any shape other than a rectangular parallelepiped, as long as multiple batteries BT can be housed in the case CS in a juxtaposed state. For example, it may be a polygonal columnar shape, a cylindrical shape, or an elliptical cylindrical shape.

[0015] A pair of terminals ET (positive or negative electrodes) for outputting power may be provided on the outer surface of the battery BT (see FIGS. 2 and 5). The power generated by the chemical reaction is extracted from the terminals ET. In the examples shown in FIGS. 2 and 5, the pair of terminals ET are provided on the top surface of the battery BT.

[0016] Furthermore, the battery BT may be provided with an explosion-proof valve EV that discharges ejected material (internal gas and / or solid matter inside the battery) due to an internal abnormality to the outside of the battery BT. The explosion-proof valve EV may function as a gas release valve (or a safety valve) that is activated when pressure inside the battery BT increases. In the examples shown in FIGS. 2 and 5 , the explosion-proof valve EV may be provided on the terminal surface (top surface) where the pair of terminals ET are provided. More specifically, the explosion-proof valve EV may be positioned so as to be sandwiched between the pair of terminals ET. With such a position of the explosion-proof valve EV, the explosion-proof valve EV can be activated regardless of whether an abnormality in the battery BT is caused by one of the pair of terminals ET.

[0017] First Insulating Plate The first insulating plate HI1 is disposed above the plurality of batteries BT. The first insulating plate HI1 has a shape that corresponds to the case CS in plan view and can be accommodated within the case CS. In the examples shown in Figures 2 and 3, the first insulating plate HI1 may have a rectangular shape in plan view. The first insulating plate HI1 is intended to have heat-resistant properties, and specifically, may be made of a material with a thermal conductivity of 0.1 W / (m·K) or less. A material with this thermal conductivity can prevent heat from being transmitted to the outside, even if heat is generated due to an internal abnormality in the battery BT.

[0018] The first insulating plate HI1 is provided at a position opposite the explosion-proof valve EV of the battery BT when viewed in a plane, and has a plurality of openings OP arranged in a first direction and slits SL provided between the openings OP (see Figures 2 and 3).

[0019] In the examples of FIGS. 2 and 3, nine openings OP may be provided corresponding to the nine batteries BT arranged along the first direction (Y direction).

[0020] The shape of the opening OP may correspond to the shape of the explosion-proof valve EV, as illustrated in Figures 2 and 3. More specifically, the size of the opening OP may be equal to or larger than the size of the explosion-proof valve EV in a plan view. In other words, the area of ​​the opening OP in a plan view may be large enough to completely surround the explosion-proof valve EV. With this configuration, if an internal abnormality occurs in the battery BT and ejection material is ejected from the explosion-proof valve EV, the ejection material will bounce off the first insulating plate HI1, reducing the likelihood of the ejection material reattaching to the abnormal battery.

[0021] In the examples shown in FIGS. 2 and 3 , at least eight slits SL may be provided between the openings OP. Furthermore, slits SL may also be provided outside the outermost opening OP. In the examples shown in FIGS. 2 and 3 , one slit SL may be provided on the +Y direction side of the opening OP located furthest in the +Y direction. As a result, nine slits SL may be provided corresponding to the number of openings OP. As shown in FIGS. 2 and 3 , eight of the nine slits SL are provided between each opening OP and another opening OP adjacent to that opening OP. Furthermore, one of the nine slits SL is provided on the +Y direction side of the opening OP located furthest in the +Y direction.

[0022] The protrusions PP of the second insulating plate HI2 (described later) are inserted into the slits SL, which reduces the difficulty of aligning the battery BT with the first insulating plate HI1 compared to the conventional battery module in which positioning pins are fitted into mounting holes to provide point contact.

[0023] Second Insulating Plates The second insulating plates HI2 are disposed between at least a plurality of batteries BT. In the example shown in FIG. 2, eight second insulating plates HI2 may be disposed between the batteries BT. Furthermore, second insulating plates HI2 may be disposed outside the outermost battery BT. In the example shown in FIG. 2, one second insulating plate HI2 may be disposed on the +Y direction side of the battery BT furthest in the +Y direction. As a result, nine second insulating plates HI2 may be disposed corresponding to the number of batteries BT. As shown in FIGS. 2 and 6, eight of the nine second insulating plates HI2 are disposed between each battery BT and another battery BT adjacent to that battery BT. Furthermore, one of the nine second insulating plates HI2 is disposed on the +Y direction side of the battery BT furthest in the +Y direction.

[0024] The second insulating plate HI2 is intended to have heat-resistant properties, and specifically, a material with a thermal conductivity of 0.1 W / (m·K) or less may be used. If a material with this thermal conductivity is used, even if heat is generated due to an internal abnormality in a battery BT, the second insulating plate HI2 arranged between the batteries BT can make it difficult for the heat to be transmitted to the battery with the internal abnormality and the adjacent battery.

[0025] As an example of a material with low thermal conductivity, the second insulating plate HI2 may contain a fibrous material. Specifically, the fibrous material may be glass wool. Such a material can effectively insulate between batteries. A specific example of the second insulating plate HI2 containing a fibrous material is a structure having a layer of fibrous material and two insulating flame-retardant sheet layers sandwiching the layer of fibrous material. Another specific example of the second insulating plate HI2 is a structure having an adhesive layer on one side of the layer of fibrous material.

[0026] As shown in Fig. 4, the second insulating plate HI2 has a main body portion BP facing the battery BT and a protrusion portion PP protruding from the main body portion BP toward the first insulating plate HI1. Specifically, the protrusion portion PP may protrude in the -Z direction in Fig. 4 relative to the main body portion BP.

[0027] As a specific example of the size of the main body portion BP, the width dimension A1 (see FIG. 4) of the main body portion BP may be equal to or greater than the width dimension B1 (see FIG. 5) of the battery BT, and the height dimension A2 (see FIG. 4) of the main body portion BP may be equal to or greater than the height dimension B2 (see FIG. 5) of the battery BT. As used herein, the "width dimension of the main body portion BP" and "height dimension of the main body portion BP" refer to the maximum dimension in the X direction and the maximum dimension in the Z direction of the main body portion BP excluding the protrusion PP. Similarly, the "width dimension of the battery BT" and "height dimension of the battery BT" refer to the maximum dimension in the X direction and the maximum dimension in the Z direction of the battery BT. This dimensional relationship allows the second insulating plate HI2 to adequately cover the adjacent surfaces of the batteries BT, making it difficult for heat to be transmitted between the internally abnormal battery and the adjacent battery.

[0028] The protrusion PP is inserted into the slit SL of the first insulating plate HI1 (see FIGS. 6 and 7) and covers the opening OP of the first insulating plate HI1 (see FIG. 8). In this way, the protrusion PP covers the opening OP, which further reduces the possibility that ejected material from an abnormal battery will come into contact with a normal battery adjacent to the abnormal battery. This effect will be described in detail with reference to FIG. 9.

[0029] 9, if an internal abnormality occurs in one battery BT1 and ejected material is ejected from the explosion-proof valve EV1, the protrusion PP1 covering the opening OP1 may be released, possibly causing the ejected material to eject above the first insulating plate HI1. However, for the normal battery BT2 adjacent to the battery BT1 with the internal abnormality, the protrusion PP2 covers the opening OP2 and the explosion-proof valve EV2, preventing the ejected material from adhering to the normal battery BT2.

[0030] In a preferred embodiment of the invention, the protrusion PP inserted into the slit SL may be bent toward the opening OP (see FIG. 8). This configuration eliminates the need for thermal caulking to position the insulating plate and the electrical connection assembly, as in the prior art, and allows for a simple method of positioning the first insulating plate HI1 and the battery BT. Furthermore, the protrusion PP can adequately cover the area around the explosion-proof valve EV, further reducing the risk of ejection from an abnormal battery coming into contact with adjacent normal batteries.

[0031] As a specific example of the size of the protrusion PP, the protrusion dimension A3 (see FIG. 4) of the protrusion PP may be shorter than the dimension L1 (see FIG. 3) between the slits. In this specification, the "protrusion dimension of the protrusion PP" refers to the dimension A3 along the -Z direction from the boundary between the protrusion PP and the main body portion BP to the position where the protrusion PP protrudes the most. Such a protrusion dimension can reduce interference with adjacent bent protrusions PP.

[0032] Furthermore, the width A4 of the protrusion PP (see FIG. 4) may be shorter than the distance B3 between the terminals of the battery BT (see FIG. 5). In this specification, the "width of the protrusion PP" refers to the maximum dimension in the X direction of the protrusion PP protruding from the main body BP. This width reduces interference between the terminals ET of the battery BT and the protrusion PP.

[0033] - Tab assembly (additional configuration) - The tab assembly TA (see Figure 2) may include a base member BB, a tab TB and an external output terminal OT arranged on the base member BB, a tab side opening TO arranged to correspond to the explosion-proof valve EV of the battery BT, and a tab side slit TS arranged to correspond to the slit SL of the first insulating plate HI1.

[0034] The base member BB may have a shape that corresponds to the case CS in a plan view so that it can be housed within the case CS. In the example shown in Figure 2, the base member BB may have a rectangular shape in a plan view. The base member BB may be made of an insulating material to electrically insulate it from the tab TB.

[0035] The tab TB may electrically connect the terminal ET (positive electrode) of one battery BT to the terminal (negative electrode) of the other battery BT among the batteries BT arranged in the first direction (Y direction), thereby connecting the batteries arranged in the first direction (Y direction) in series. The terminal ET (positive electrode) of one battery BT may also be electrically connected to the terminal (positive electrode) of the other battery BT to connect the batteries arranged in the first direction (Y direction) in parallel. Note that any configuration other than the tab TB may be used as long as it is capable of electrically connecting the terminals of the batteries BT. Specifically, a connector or a harness may be used instead of the tab TB.

[0036] The external output terminal OT may output the power of the battery BT electrically connected by the tab TB to the outside. As described above, the external output terminal OT may be provided so as to protrude from the outer edge of the base member BB in order to expose the external output terminal OT from the case CS.

[0037] The tab-side openings TO may be provided corresponding to the nine batteries BT arranged along the first direction (Y direction) and the nine openings OP provided in the first insulating plate HI1, as illustrated in Figure 2. When an internal abnormality occurs in a battery BT and ejection material is ejected from the explosion-proof valve EV, the ejection material may pass through the tab-side openings TO.

[0038] The shape of the tab-side opening TO may correspond to the shape of the explosion-proof valve EV, as illustrated in FIG. 2 . More specifically, in a plan view, the size of the tab-side opening TO may be equal to or larger than the size of the explosion-proof valve EV. In other words, in a plan view, the tab-side opening TO may have an area large enough to completely surround the explosion-proof valve EV. With this configuration, if an internal abnormality occurs in the battery BT and ejection material is ejected from the explosion-proof valve EV, the ejection material will bounce off the tab assembly TA, reducing the likelihood of the ejection material reattaching to the abnormal battery.

[0039] 2, the tab-side slits TS may be provided corresponding to the nine slits SL provided in the first insulating plate HI1. The protrusions PP of the second insulating plate HI2 may be inserted into the tab-side slits TS. With this configuration, the protrusions PP are inserted into the tab-side slits TS of the tab assembly TA and the slits SL of the first insulating plate HI1, and can contribute to positioning between the tab assembly TA and the first insulating plate HI1.

[0040] --Case (additional configuration)-- The case CS may be composed of a first case CS1 and a second case CS2 (see FIG. 2). The first case CS1 and the second case CS2 may form an accommodation space that accommodates the first insulating plate HI1, the tab assembly TA, the battery BT, and the second insulating plate HI2. Note that the example in FIG. 2 illustrates an arrangement in which the accommodation space is formed by two cases (the first case CS1 and the second case CS2), but this is not limited to this arrangement, and the case may be composed of three or more cases.

[0041] The case CS may be made of any material, including resin materials (e.g., plastic) and metal materials. 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. Note that a highly rigid material may be used for the case CS to more appropriately accommodate the battery BT (described below).

[0042] The case CS may have a rectangular shape in a plan view, as illustrated in Figures 1 and 2. The rectangular shape may have a long side along a first direction (Y direction) in which the batteries BT housed in the case CS are arranged side by side, and a short side along a second direction (X direction) perpendicular to the first direction.

[0043] Furthermore, as illustrated in Figures 1 and 2, the case CS may be provided with a notch CA that exposes the external output terminal OT of the tab assembly TA from the case CS. In the example illustrated in Figures 1 and 2, the notch CA may be provided on the side surface of the first case CS1 facing the ±Y direction (the first direction in which the batteries BT are arranged side by side). Note that the notch CA is not limited to being provided on the first case CS1, and may also be provided on the second case CS2. Furthermore, the position of the notch CA may be provided on the ±X direction surface of the case.

[0044] As described above, the battery module BM of the present disclosure includes a plurality of batteries BT arranged in a first direction and equipped with an explosion-proof valve EV on its upper surface, a first insulating plate HI1 arranged above the plurality of batteries BT, and a second insulating plate HI2 arranged between the plurality of batteries BT. The first insulating plate HI1 has a plurality of openings OP arranged in the first direction, each located opposite the explosion-proof valve EV, and slits SL between the openings OP. The second insulating plate HI2 has a main body portion BP facing the batteries BT and a protrusion PP protruding from the main body portion BP toward the first insulating plate HI1. The protrusion PP is inserted into the slit SL and covers the opening OP. Therefore, according to the battery module BM of the present disclosure, the difficulty of aligning the batteries BT with the first insulating plate HI1 can be reduced by inserting the protrusion PP into the slit SL. Furthermore, since the protrusion PP covers the opening OP, it is possible to further reduce the possibility that ejected material from an abnormal battery will come into contact with normal batteries adjacent to the abnormal battery.

[0045] 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.

[0046] The tab and battery module of the present disclosure are as follows: <1> A battery module comprising: a plurality of batteries each having an explosion-proof valve on its upper surface and arranged in a line in a first direction; a first insulating plate arranged above the plurality of batteries; and a second insulating plate arranged between the plurality of batteries, wherein the first insulating plate is provided at a position facing the explosion-proof valve and has a plurality of openings arranged in the first direction and slits provided between the openings; and the second insulating plate has a main body facing the batteries and a protruding portion protruding from the main body toward the first insulating plate, wherein the protruding portion is inserted into the slit and covers the opening. <2> The battery module described in <1>, wherein the protruding portion inserted into the slit is bent toward the opening. <3> The battery module described in <1> or <2>, wherein the protruding dimension of the protruding portion is shorter than the dimension between the slits. <4> The battery module according to any one of <1> to <3>, wherein the width dimension of the protrusion is shorter than the distance between terminals of the battery. <5> The battery module according to any one of <1> to <4>, wherein the second insulating board is made of a fibrous material. <6> The battery module according to any one of <1> to <5>, wherein the width dimension of the main body is equal to or greater than the width dimension of the battery, and the height dimension of the main body is equal to or greater than the height dimension of the battery. <7> The battery module according to any one of <1> to <6>, wherein the size of the opening in a plan view is equal to or greater than the size of the explosion-proof valve.

[0047] The present disclosure can be easily manufactured and is suitable for use as a battery module that further reduces the likelihood of ejection material from an abnormal battery coming into contact with a normal battery adjacent to the abnormal battery.

[0048] BM Battery module BT Battery ET Terminal EV Explosion-proof valve HI1 First heat insulating plate OP Opening SL Slit TA Tab assembly BB Base member TB Tab OT External output terminal TO Tab-side opening TS Tab-side slit HI2 Second heat insulating plate PP Protrusion BP Main body CS Case CS1 First case CS2 Second case CA Notch

Claims

1. It has an explosion-proof valve on the top surface, and multiple batteries arranged in a line in the first direction, A first insulating plate positioned above the multiple batteries, The device comprises a second insulating plate placed between a plurality of the aforementioned batteries, The first insulating plate is provided at positions opposite to the explosion-proof valve and comprises a plurality of openings arranged in the first direction and slits provided between the openings, The second insulating plate comprises a main body facing the battery and a projection extending from the main body toward the first insulating plate. A battery module in which the protrusion is inserted into the slit and the protrusion covers the opening.

2. The battery module according to claim 1, wherein the protruding portion inserted into the slit is bent toward the opening.

3. The battery module according to claim 1, wherein the protruding dimension of the protruding portion is shorter than the dimension between the slits.

4. The battery module according to claim 1, wherein the width dimension of the protrusion is shorter than the distance between the terminals of the battery.

5. The battery module according to claim 1, wherein the second insulating plate includes a fibrous material.

6. The battery module according to claim 1, wherein the width dimension of the main body is greater than or equal to the width dimension of the battery, and the height dimension of the main body is greater than or equal to the height dimension of the battery.

7. The battery module according to claim 1, wherein, in a plan view, the size of the opening is greater than or equal to the size of the explosion-proof valve.