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

Technical Field

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

Background Art

[0002] Patent Document 1 discloses a battery module including a battery (2) and a heat insulating plate (4), wherein the heat insulating plate (4) is provided on the side approaching the upper case (12) of the electrical connection assembly (3), and a plurality of pressure relief holes (41) are provided in the heat insulating plate (4), and each pressure relief hole (41) is provided corresponding to the explosion-proof valve (21) of the battery (2) (see FIGS. 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 after the positioning pin (311) is fitted into the mounting hole (42), it is fixed in the mounting hole (42) by hot caulking.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the battery module described in Patent Document 1, since the mounting hole (42) and the positioning pin (311) are used for fixing the heat insulating plate (4), there is a problem that it is difficult to align all the positioning pins (311) with the mounting hole (42). And, since the process of fixing the positioning pin (311) to the mounting hole (42) by hot caulking is passed through, the number of processes increases and the manufacturing cost is high.

[0006] Furthermore, the ejected material from battery (2) due to thermal runaway could pass through the pressure relief hole (41) and potentially flow to the normal battery (2) through the adjacent pressure relief hole (41). As a result, there was a risk of adverse effects on the normal battery (2).

[0007] This disclosure has been made in view of the above. Specifically, the primary purpose of this disclosure is to provide a battery module that can be easily manufactured and that further reduces the contact between ejected material from a malfunctioning battery and a normal battery adjacent to the malfunctioning battery. [Means for solving the problem]

[0008] The battery module disclosed herein is 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 protruding portion extending from the main body toward the first insulating plate. The protruding portion is inserted into the slit, and the protruding portion covers the opening. [Effects of the Invention]

[0009] According to this disclosure, manufacturing can be easily carried out, and the likelihood of ejected material from a malfunctioning battery coming into contact with a normal battery adjacent to the malfunctioning battery can be further reduced. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a perspective view of a battery module according to one embodiment. [Figure 2]Figure 2 is an exploded perspective view of a battery module according to one embodiment. [Figure 3] Figure 3 is a plan view of the first insulation panel. [Figure 4] Figure 4 is a front view of the second insulation panel. [Figure 5] Figure 5 is a front view of the battery. [Figure 6] Figure 6 is a schematic diagram showing the mounting state of the first insulation board and the second insulation board (this schematic diagram corresponds to the cross-sectional view cut along the line VI-VI in Figure 2). [Figure 7] Figure 7 is an enlarged schematic diagram of the dashed area in Figure 6. [Figure 8] Figure 8 is a schematic diagram showing the state in which the protruding part is folded in Figure 7. [Figure 9] Figure 9 is a schematic diagram illustrating a state in which a malfunction occurs in one of the batteries installed in a battery module. [Modes for carrying out the invention]

[0011] The following describes in more detail a battery module according to one embodiment of this disclosure. While the description will refer to the drawings as necessary, the various elements in the drawings are provided schematically and illustratively for the purpose of understanding this disclosure, and their appearance and dimensional ratios may differ from those of the actual product.

[0012] In this specification, "plan view" refers to the state when an object (e.g., a battery module) is placed on a surface and viewed from directly above in the direction of its thickness (height), and is synonymous with a plan view. For example, a plan view is the state when viewed along the positive direction in the "Z direction" as shown in Figure 1. In this specification, "side view" refers to the state when an object (e.g., a battery module) is placed on a surface and viewed from the side perpendicular to its thickness (height), and is synonymous with a side view. For example, a side view is the state when viewed along the positive (or negative) direction in the "Y direction" as shown in Figure 1. In this specification, "front view" refers to the state when an object (e.g., a battery module) is placed on a surface and viewed from the front perpendicular to its thickness (height), and is synonymous with a front view. For example, a front view is the state when viewed along the positive direction in the "X direction" as shown in Figure 1. The "positive direction" mentioned above refers to the direction indicated by the X, Y, and Z arrows in the diagram, while the "negative direction" refers to the direction opposite to the direction indicated by the X, Y, and Z arrows in the diagram. Furthermore, the X, Y, and Z directions are mutually orthogonal.

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

[0014] -battery- The battery BT is intended to be a chemical battery that mainly converts chemical energy into direct current power through a chemical reaction. The battery BT used in the battery module BM of this embodiment is housed in the case CS in a state of being arranged along the first direction (the Y direction in FIG. 2). In the example shown in FIG. 2, a mode in which nine batteries BT are arranged along the first direction is shown. The shape of the battery BT is intended to be a rectangular parallelepiped battery as exemplified in FIGS. 2 and 5. By making the battery BT have a rectangular parallelepiped shape, a plurality of batteries BT can be housed in the case CS in a side-by-side arrangement. Note that the shape of the battery BT may be other than a rectangular parallelepiped shape as long as a plurality of batteries BT can be arranged side by side and housed in the case CS. For example, it may be a polygonal columnar shape, a cylindrical shape, or an elliptical cylindrical shape.

[0015] A pair of terminals ET (positive electrode or negative electrode) 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 taken out from the terminals ET. In the examples shown in FIGS. 2 and 5, the pair of terminals ET are provided on the upper surface of the battery BT.

[0016] Furthermore, the battery BT may be provided with an explosion-proof valve EV for discharging ejecta (internal gas and / or solid matter inside the battery) ejected due to an internal abnormality to the outside of the battery BT. The explosion-proof valve EV may function as a gas discharge valve (or a safety valve) that operates when the pressure inside the battery BT rises. In the examples shown in FIGS. 2 and 5, the explosion-proof valve EV may be provided on the terminal surface (upper surface) where the pair of terminals ET are provided. More specifically, the explosion-proof valve EV may be arranged 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 operated regardless of which of the pair of terminals ET causes an abnormality in the battery BT.

[0017] -First heat insulation plate- The first insulating plate HI1 is positioned above the multiple batteries BT. The first insulating plate HI1 has a shape that corresponds to the case CS in a plan view and can be housed inside the case CS, and in the examples in Figures 2 and 3, it may have a rectangular shape in a plan view. Furthermore, the first insulating plate HI1 is intended to have poor heat conductivity, and specifically, a material with a thermal conductivity of 0.1 W / (m·K) or less may be used. If a material with such thermal conductivity is used, even if heat is generated due to an internal abnormality in the batteries BT, it will be difficult to transfer that heat to the outside.

[0018] The first insulation plate HI1 is provided at positions opposite to the explosion-proof valve EV of the battery BT in a plan view, and comprises a plurality of openings OP arranged in the first direction, and slits SL provided between the openings OP (see Figures 2 and 3).

[0019] In the examples shown in Figures 2 and 3, there may be nine openings OP, corresponding to 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, in a plan view, the size of the opening OP may be larger than or equal to the size of the explosion-proof valve EV. In other words, in a plan view, the area of ​​the opening OP may be large enough to completely enclose the explosion-proof valve EV. With such a configuration, if an internal malfunction occurs in the battery BT and ejected material from the explosion-proof valve EV, the ejected material will bounce off the first insulation plate HI1, reducing the likelihood of the ejected material reattaching to the malfunctioning battery.

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

[0022] The protruding portion PP of the second heat insulating plate HI2, described later, is inserted into the slit SL. Therefore, compared to the conventional battery module configuration in which a positioning pin is fitted into a mounting hole in a point contact manner, the difficulty of aligning the battery BT and the first heat insulating plate HI1 can be reduced.

[0023] -Second insulation board- The second insulating plate HI2 is placed between at least several battery BTs. In the example in Figure 2, eight may be provided between battery BTs. Furthermore, the second insulating plate HI2 may also be provided outside the outermost battery BT. In the example in Figure 2, one second insulating plate HI2 may be provided on the +Y side of the battery BT closest to the +Y direction. As a result, nine second insulating plates HI2 may be provided, corresponding to the number of battery BTs. As shown in Figures 2 and 6, eight of the nine second insulating plates HI2 are provided one at a time between one battery BT and another battery BT adjacent to that battery BT. Also, one of the nine second insulating plates HI2 is provided on the +Y side of the battery BT closest to the +Y direction.

[0024] The second insulating plate HI2 is intended to have poor heat conductivity, 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 malfunction in battery BT, the second insulating plate HI2 placed between batteries BT can make it difficult for the heat to be transferred from the malfunctioning battery to the adjacent battery.

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

[0026] As shown in Figure 4, the second insulation plate HI2 comprises a main body BP facing the battery BT and a protruding portion PP projecting from the main body BP toward the first insulation plate HI1. Specifically, the protruding portion PP may project in the -Z direction in Figure 4 relative to the main body BP.

[0027] As a specific example of the size of the main body BP, the width dimension A1 (see Figure 4) of the main body BP is greater than or equal to the width dimension B1 (see Figure 5) of the battery BT, and the height dimension A2 (see Figure 4) of the main body BP is greater than or equal to the height dimension B2 (see Figure 5) of the battery BT. In this specification, "width dimension of the main body BP" and "height dimension of the main body BP" refer to the maximum dimensions in the X direction and Z direction of the main body BP, excluding the protruding part PP. Similarly, in this specification, "width dimension of the battery BT" and "height dimension of the battery BT" refer to the maximum dimensions in the X direction and Z direction of the battery BT. With such dimensional relationships, the second insulation plate HI2 can appropriately cover the adjacent surfaces of the batteries BT, making it difficult to transfer heat from an internally abnormal battery to an adjacent battery.

[0028] The protruding portion PP is inserted into the slit SL of the first insulation plate HI1 (see Figures 6 and 7) and covers the opening OP of the first insulation plate HI1 (see Figure 8). In this way, because the protruding portion PP covers the opening OP, the likelihood of ejected material from a malfunctioning battery coming into contact with a normal battery adjacent to the malfunctioning battery can be further reduced. The effects of this will be described in detail with reference to Figure 9.

[0029] As shown in Figure 9, if an internal malfunction occurs in one of the batteries BT1 and ejected material from the explosion-proof valve EV1, in some cases the protruding portion PP1 covering the opening OP1 may be released, and the ejected material may be ejected above the first insulation plate HI1. However, with respect to the normal battery BT2 adjacent to the battery BT1 with the internal malfunction, the protruding portion PP2 covers the opening OP2 and the explosion-proof valve EV2, thus preventing the ejected material from adhering to the normal battery BT2.

[0030] As a preferred covering configuration for the opening OP, the protruding portion PP inserted into the slit SL may be bent toward the opening OP (see Figure 8). With this configuration, the positioning of the insulation plate and the electrical connection assembly by heat crimping, as in the conventional technology, is not required, and the positioning of the first insulation plate HI1 and the battery BT can be performed by a simple method. Furthermore, the area around the explosion-proof valve EV can be appropriately covered by the protruding portion PP, and the likelihood of ejected material from a malfunctioning battery coming into contact with a normal battery adjacent to the malfunctioning battery can be further reduced.

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

[0032] Furthermore, the width dimension A4 of the protruding portion PP (see Figure 4) may be shorter than the terminal distance B3 of the battery BT (see Figure 5). In this specification, "width dimension of the protruding portion PP" refers to the maximum dimension in the X direction of the protruding portion PP that protrudes from the main body BP. With such a width dimension, interference between the terminals ET of the battery BT and the protruding portion PP can be reduced.

[0033] - Tab Assembly (Additional Components) - The tab assembly TA (see Figure 2) may comprise a base member BB, a tab TB and an external output terminal OT disposed 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 insulation plate HI1.

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

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

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

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

[0038] The shape of the tab-side opening TO may correspond to the shape of the explosion-proof valve EV, as illustrated in Figure 2. More specifically, in a plan view, the size of the tab-side opening TO may be larger than or equal to 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 enclose the explosion-proof valve EV. With such a configuration, if an internal malfunction occurs in the battery BT and ejected material from the explosion-proof valve EV, the ejected material will bounce off the tab assembly TA, reducing the likelihood of the ejected material reattaching to the malfunctioning battery.

[0039] The tab-side slit TS may be provided in accordance with the nine slits SL provided in the first insulation plate HI1, as illustrated in Figure 2. The protruding portion PP of the second insulation plate HI2 may be inserted into the tab-side slit TS. With this configuration, the protruding portion PP is inserted into the tab-side slit TS of the tab assembly TA and the slits SL of the first insulation plate HI1, and can therefore contribute to the positioning between the tab assembly TA and the first insulation plate HI1.

[0040] -Case (additional configuration)- Case CS may consist of a first case CS1 and a second case CS2 (see Figure 2). The first case CS1 and the second case CS2 may then form a housing space for housing the first insulation plate HI1, the tab assembly TA, the battery BT, and the second insulation plate HI2. In the example in Figure 2, a configuration in which the housing space is composed of two cases (first case CS1 and second case CS2) is illustrated, but the configuration is not limited to this and may consist of three or more cases.

[0041] The case CS may be made of any material, including resin materials (e.g., plastic) or 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. Furthermore, from the viewpoint of more suitably housing the battery BT, etc., described later, a material with high rigidity may be used for the case CS.

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

[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 examples in Figures 1 and 2, the notch CA may be provided on the side of the first case CS1 in 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 the form provided on the first case CS1, but may also be provided on the second case CS2. Also, 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 this disclosure is equipped with an explosion-proof valve EV on its upper surface and comprises a plurality of batteries BT arranged in a line in a first direction, a first heat insulating plate HI1 positioned above the plurality of batteries BT, and a second heat insulating plate HI2 positioned between the plurality of batteries BT. The first heat insulating plate HI1 is provided at positions facing the explosion-proof valve EV and comprises a plurality of openings OP arranged in a line in the first direction, and slits SL provided between the openings OP. The second heat insulating plate HI2 comprises a main body BP facing the batteries BT and a protruding portion PP protruding from the main body BP toward the first heat insulating plate HI1. The protruding portion PP is inserted into the slits SL and covers the openings OP. Therefore, with the battery module BM of this disclosure, the difficulty of aligning the batteries BT and the first heat insulating plate HI1 can be reduced by inserting the protruding portion PP into the slits SL. Furthermore, because the protruding portion PP covers the openings OP, it is possible to further reduce the chance of ejected material from a malfunctioning battery coming into contact with a normal battery adjacent to the malfunctioning battery.

[0045] The embodiments disclosed herein are illustrative in all respects and do not constitute a limiting interpretation. Therefore, the technical scope of this disclosure is not construed solely by the embodiments described above, but is defined based on the claims. Furthermore, the technical scope of this disclosure includes all modifications within the meaning and scope of equivalence to the claims.

[0046] The tabs and battery modules described in this disclosure are as follows: <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 protruding portion 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 protruding portion inserted into the slit is bent toward the opening. <1> The battery module described above. <3> The protruding dimension of the aforementioned protrusion is shorter than the dimension between the slits. <1> or <2> The battery module described above. <4> The width dimension of the protrusion is shorter than the distance between the terminals of the battery. <1> ~ <3> The battery module listed in one of the following. <5> The first second insulation board is made of a fibrous material. <1> ~ <4> The battery module listed in one of the following. <6> 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. <1> ~ <5> The battery module listed in one of the following. <7> In a plan view, the size of the opening is greater than or equal to the size of the explosion-proof valve. <1> ~ <6> The battery module listed in one of the following. [Industrial applicability]

[0047] This disclosure can be suitably used as a battery module that is easy to manufacture and reduces the likelihood of ejected material from a malfunctioning battery coming into contact with a normal battery adjacent to the malfunctioning battery. [Explanation of Symbols]

[0048] BM Battery Module BT battery ET terminal EV explosion-proof valve HI1 First Insulation Board OP opening SL Slit TA Tab Assembly BB base component TB tab OT External Output Terminal TO tab side opening TS tab side slit HI2 Second Insulation Board PP protrusion BP main unit CS Case CS1 Case 1 CS2 Case 2 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.

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