Battery module

Abstract

To suppress the impact of fuse scattering on materials surrounding the fuse.SOLUTION: A battery module 1 includes a battery cell 100, a fuse 233 electrically connected to the battery cell 100 and extending in a predetermined direction, and a surrounding heat-resistant body 211 and a covering heat-resistant body 311 that at least partially surround the fuse 233 around the predetermined direction.SELECTED DRAWING: Figure 4

Description

[Technical Field]

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

[0002] In recent years, various battery modules have been developed. For example, as described in Patent Document 1, a battery module includes a plurality of battery cells stacked in a predetermined direction and a bus bar electrically connected to the plurality of battery cells. In the battery module described in Patent Document 1, the bus bar has a fuse portion. This battery module further includes an insulation cover that surrounds the periphery of the bus bar and a module cover fixed to the top of the insulation cover. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019 / 069837 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, as described in Patent Document 1, a fuse may be electrically connected to a battery cell. When a fuse melts, the fuse may not only fall downward but also scatter around the fuse. However, when the fuse scatters around the fuse, it may be difficult to prevent the effects on components around the fuse.

[0005] One example of an object of the present invention is to suppress the influence of a blown fuse on members surrounding the fuse. Other objects of the present invention will become apparent from the description of this specification. [Means for solving the problem]

[0006] One aspect of the present invention is as follows. [1] A battery cell; a fuse electrically connected to the battery cell and extending in a predetermined direction; a heat-resistant body at least partially surrounding the fuse around the predetermined direction; A battery module comprising: [2] a voltage detection unit electrically connected to the battery cell; a holder that holds the voltage detection unit; Furthermore, The battery module according to [1], wherein at least a portion of the heat-resistant body is provided on the holder. [3] The battery pack further includes a housing that houses the battery cell. The battery module according to [1] or [2], wherein the housing includes at least a part of the heat-resistant body. [Effects of the Invention]

[0007] According to the above aspect of the present invention, it is possible to suppress the influence of the fuse scattering on the members around the fuse. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of a battery module according to an embodiment. [Figure 2] FIG. 2 is an exploded perspective view of the battery module according to the embodiment. [Figure 3] FIG. 2 is an exploded enlarged perspective view of a right front portion of the battery module according to the embodiment. [Figure 4] 2 is a cross-sectional view taken along the line AA in FIG. 1. [Figure 5] FIG. 5 is a diagram showing a modification of FIG. 4. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments and modifications of the present invention will be described with reference to the drawings. In all the drawings, like components are designated by like reference numerals, and descriptions thereof will be omitted as appropriate.

[0010] Fig. 1 is a perspective view of a battery module 1 according to an embodiment. Fig. 2 is an exploded perspective view of the battery module 1 according to an embodiment. Fig. 3 is an exploded enlarged perspective view of the right front part of the battery module 1 according to an embodiment.

[0011] For ease of explanation, arrows indicating the X, Y, and Z directions are shown in each figure. Hereinafter, unless otherwise specified, the tip of an arrow indicating the X direction refers to the rear side of the battery module 1, and the base end of an arrow indicating the X direction refers to the front side of the battery module 1. The Y direction is perpendicular to the X direction. The Y direction is the left-to-right direction of the battery module 1. Hereinafter, unless otherwise specified, the tip of an arrow indicating the Y direction refers to the left side of the battery module 1, and the base end of an arrow indicating the Y direction refers to the right side of the battery module 1. The Z direction is perpendicular to both the X and Y directions. The Z direction is the up-down direction of the battery module 1. Hereinafter, unless otherwise specified, the tip of an arrow indicating the Z direction refers to the upper side of the battery module 1, and the base end of an arrow indicating the Z direction refers to the lower side of the battery module 1. Hereinafter, as necessary, the direction perpendicular to the X direction will be referred to as the YZ plane direction, the direction perpendicular to the Y direction will be referred to as the ZX plane direction, and the direction perpendicular to the Z direction will be referred to as the XY plane direction. The relationship between each of the X direction, Y direction, and Z direction and each of the front-rear direction, left-right direction, and up-down direction of the battery module 1 is not limited to the example described above.

[0012] The structure of the battery module 1 will be described with reference to FIGS.

[0013] The battery module 1 includes a cell stack 10, a front voltage detector 20, a rear voltage detector 20', and a housing 30.

[0014] As shown in FIG. 2, the cell stack 10 has a plurality of battery cells 100 and a plurality of compression pads 110. The plurality of battery cells 100 and the plurality of compression pads 110 are arranged alternately in the Y direction. A compression pad 110 is disposed on both sides of each battery cell 100 in the Y direction. The plurality of battery cells 100 and the plurality of compression pads 110 are compressed in the Y direction by a right plate 330 and a left plate 340, which will be described later. This makes it possible to suppress displacement of the battery cells 100 in the ZX plane direction.

[0015] As shown in Fig. 2, the longitudinal direction of each battery cell 100 is approximately parallel to the X direction. The lateral direction of each battery cell 100 is approximately parallel to the Z direction. The thickness direction of each battery cell 100 is approximately parallel to the Y direction. The multiple battery cells 100 are stacked in the Y direction. Note that the shape of each battery cell 100 is not limited to this example.

[0016] Each battery cell 100 includes a battery element (not shown), an outer casing 102, a positive electrode tab 104, and a negative electrode tab 106. The battery element includes a plurality of positive electrodes and a plurality of negative electrodes (not shown) alternately stacked in the Y direction, and a separator (not shown) positioned between adjacent positive electrodes and negative electrodes in the Y direction. The outer casing 102 seals the battery element and an electrolyte (not shown). The positive electrode tab 104 is electrically connected to the positive electrode of the battery element. The positive electrode tab 104 is pulled out from one of both sides of the outer casing 102 in the X direction. The negative electrode tab 106 is electrically connected to the negative electrode of the battery element. The negative electrode tab 106 is pulled out from the other side of the outer casing 102 in the X direction. However, the structure of each battery cell 100 is not limited to this example.

[0017] In this embodiment, a plurality of cell groups 100G are connected in series from the cell group 100G located at one end in the Y direction to the cell group 100G located at the other end in the Y direction. Each cell group 100G includes a plurality of battery cells 100 connected in parallel. In this embodiment, each cell group 100G includes two battery cells 100 adjacent to each other in the Y direction. Two positive electrode tabs 104 drawn from the two battery cells 100 included in each cell group 100G face the same side in the X direction. Two negative electrode tabs 106 drawn from the two battery cells 100 included in each cell group 100G face the same side in the X direction. The positive electrode tab 104 and the negative electrode tab 106 drawn from one of the cell groups 100G adjacent to each other in the Y direction face opposite each other in the X direction. Two cell groups 100G adjacent to each other in the Y direction include tab groups 108 located in front of or behind the two cell groups 100G. The tab groups 108 include positive electrode tabs 104 and negative electrode tabs 106 joined to each other. The positive electrode tabs 104 and negative electrode tabs 106 included in the tab groups 108 are joined to each other by, for example, laser welding. Therefore, the multiple tab groups 108 located in front of the cell stack 10 and the multiple tab groups 108 located in the rear of the cell stack 10 are arranged alternately.

[0018] In this embodiment, positive electrode tabs 104 extend forward from the two battery cells 100 located at the right end of the cell stack 10. Hereinafter, as needed, these positive electrode tabs 104 are referred to as terminal positive electrode tabs 104T. However, the number of terminal positive electrode tabs 104T may be one or three or more. Furthermore, negative electrode tabs 106 extend backward from the two battery cells 100 located at the left end of the cell stack 10. Hereinafter, as needed, these negative electrode tabs 106 are referred to as terminal negative electrode tabs 106T. However, the number of terminal negative electrode tabs 106T may be one or three or more.

[0019] The configuration of the cell stack 10 is not limited to the above example. For example, each cell group 100G may include three or more battery cells 100 connected in parallel. Alternatively, multiple single battery cells 100 may be connected in series from a battery cell 100 located at one end in the Y direction to a battery cell 100 located at the other end in the Y direction. Furthermore, the positions of the terminal positive electrode tabs 104T and terminal negative electrode tabs 106T are not limited to the above example. The positions of the terminal positive electrode tabs 104T and terminal negative electrode tabs 106T vary depending on the number of cell groups 100G. For example, depending on the number of cell groups 100G, both the terminal positive electrode tabs 104T and terminal negative electrode tabs 106T may be located at the front or rear of the cell stack 10.

[0020] As shown in FIG. 2, the front voltage detection device 20 includes a front holder 210 , a plurality of front voltage detection sections 220 , a plurality of front voltage detection lines 222 , a front connector 224 , and a positive bus bar 230 .

[0021] The front holder 210 is disposed in front of the cell stack 10. The front holder 210 defines a plurality of front openings 212. Each of the plurality of tab groups 108 located in the front of the cell stack 10 is exposed forward through each of the plurality of front openings 212. The front holder 210 integrally holds a plurality of front voltage detection portions 220 and a plurality of front voltage detection wires 222.

[0022] The multiple front voltage detection units 220 are attached to the front support body 210. Each of the multiple front voltage detection units 220 is joined to the front surface of each of the multiple tab groups 108 located at the front of the cell stack 10, for example, by laser welding. The multiple front voltage detection units 220 are electrically connected to the front connector 224 via multiple front voltage detection wires 222. The multiple front voltage detection wires 222 are routed through the front support body 210. In the embodiment, by placing the front support body 210 at an appropriate position relative to the cell stack 10, each of the multiple front voltage detection units 220 can be disposed at an appropriate position relative to each of the multiple tab groups 108 located at the front of the cell stack 10.

[0023] The positive bus bar 230 is disposed at the right end of the front holding body 210. The positive bus bar 230 is substantially L-shaped. Specifically, the positive bus bar 230 includes a front horizontal conductor 232 and a front vertical conductor 234. The front horizontal conductor 232 extends substantially parallel to the Y direction. The front vertical conductor 234 extends downward from the right end of the front horizontal conductor 232 substantially parallel to the Z direction.

[0024] The front horizontal conductor 232 functions as a terminal for electrically connecting to an external device such as another battery module. Specifically, a fastening hole 232a is provided at the left end of the front horizontal conductor 232. A fastener (not shown) can be installed in the fastening hole 232a to fasten a bus bar (not shown) that is electrically connected to an external device (not shown) such as another battery module.

[0025] As shown in FIG. 3 , the front horizontal conductor 232 includes a fuse 233. The fuse 233 is located to the right of the fastening hole 232a. The fuse 233 extends approximately parallel to the Y direction. A notch is provided in the front horizontal conductor 232 behind the fuse 233. Therefore, a cross section of the fuse 233 perpendicular to the Y direction is smaller than cross sections of both sides of the front horizontal conductor 232 perpendicular to the Y direction. Therefore, when a current equal to or greater than a predetermined value flows through the fuse 233, the fuse 233 can melt. However, the structure of the fuse 233 is not limited to this example. For example, the fuse 233 may be defined by a notch provided in front of the front horizontal conductor 232. Alternatively, the fuse 233 may be defined by notches provided both in front and rear of the front horizontal conductor 232. In this example, the fuse 233 is located, for example, in approximately the center of the front horizontal conductor 232 in the X direction. However, the fuse 233 may be shifted in the X direction from approximately the center in the X direction of the front horizontal conductor 232. Alternatively, the thickness of the front horizontal conductor 232 in the Z direction may be partially thinned. In this case, the fuse 233 is located at a portion of the front horizontal conductor 232 where the thickness in the Z direction is partially thin.

[0026] The front vertical conductor 234 is electrically connected to the terminal positive electrode tab 104T. The terminal positive electrode tab 104T is located to the right of the front vertical conductor 234. In the embodiment, the terminal positive electrode tab 104T and the front vertical conductor 234 are joined by laser welding. However, the method of joining the terminal positive electrode tab 104T and the front vertical conductor 234 is not limited to laser welding.

[0027] The rear voltage detection device 20′ is similar to the front voltage detection device 20 except for the following points: The rear voltage detection device 20′ includes a rear holder 210′, a plurality of rear voltage detection portions 220′, a plurality of rear voltage detection lines 222′, a rear connector 224′, and a negative bus bar 230′.

[0028] The rear retainer 210′ ​​is disposed at the rear of the cell stack 10. The rear retainer 210′ ​​defines a plurality of rear openings 212′. Each of the plurality of tab groups 108 located at the rear of the cell stack 10 is exposed rearward through each of the plurality of rear openings 212′. The rear retainer 210′ ​​integrally holds a plurality of rear voltage detection portions 220′ and a plurality of rear voltage detection wires 222′.

[0029] The multiple rear voltage detection units 220' are attached to the rear support 210'. Each of the multiple rear voltage detection units 220' is joined to the rear surface of each of the multiple tab groups 108 located at the rear of the cell stack 10, for example, by laser welding. The multiple rear voltage detection units 220' are electrically connected to the rear connector 224' via multiple rear voltage detection wires 222'. The multiple rear voltage detection wires 222' are routed through the rear support 210'. In the embodiment, by placing the rear support 210' at an appropriate position relative to the cell stack 10, each of the multiple rear voltage detection units 220' can be positioned at an appropriate position relative to each of the multiple tab groups 108 located at the rear of the cell stack 10.

[0030] The negative bus bar 230' is disposed at the left end of the rear holding body 210'. The negative bus bar 230' is substantially L-shaped. The negative bus bar 230' includes a rear horizontal conductor 232' and a rear vertical conductor 234'. The rear horizontal conductor 232' extends substantially parallel to the Y direction. The rear vertical conductor 234' extends downward from the left end of the rear horizontal conductor 232' substantially parallel to the Z direction.

[0031] The rear horizontal conductor 232' functions as a terminal for electrical connection to an external device such as another battery module, etc. Like the front horizontal conductor 232, the rear horizontal conductor 232' includes a fuse.

[0032] The rear vertical conductor 234' is electrically connected to the terminating negative electrode tab 106T. The terminating negative electrode tab 106T is located to the left of the rear vertical conductor 234'. In the embodiment, the terminating negative electrode tab 106T and the rear vertical conductor 234' are joined by laser welding. However, the method of joining the terminating negative electrode tab 106T and the rear vertical conductor 234' is not limited to laser welding.

[0033] The housing 30 includes a front plate 310, a rear plate 320, a right plate 330, a left plate 340, a lower plate 350, and an upper plate 360. As will be described later with reference to FIG. 4, the housing 30 further includes a coated refractory body 311.

[0034] The front plate 310 covers the cell stack 10 and the front voltage detection device 20 from the front. The front plate 310 is, for example, a metal plate such as an aluminum plate.

[0035] The rear plate 320 covers the cell stack 10 and the rear voltage detection device 20' from the rear. The rear plate 320 is, for example, a metal plate such as an aluminum plate.

[0036] The right plate 330 covers the cell stack 10, the front voltage detection device 20, and the rear voltage detection device 20' from the right side. The right plate 330 is made of a conductive material such as metal.

[0037] The left plate 340 covers the cell stack 10, the front voltage detection device 20, and the rear voltage detection device 20' from the left side. The left plate 340 is made of a conductive material such as metal.

[0038] The lower plate 350 covers the cell stack 10, the front voltage detection device 20, and the rear voltage detection device 20' from below. The lower plate 350 is made of a conductive material such as metal. A thermally conductive adhesive 352 is disposed between the upper surface of the lower plate 350 and the lower end of the cell stack 10. This allows heat generated from the cell stack 10 to be dissipated downwards in the battery module 1 through the thermally conductive adhesive 352.

[0039] The upper plate 360 ​​covers the cell stack 10, the front voltage detection device 20, and the rear voltage detection device 20' from above. The upper plate 360 ​​is made of a conductive material such as metal.

[0040] Fig. 4 is a cross-sectional view taken along the line AA in Fig. 1. In Fig. 4, the white circle with an X indicating the Y direction indicates that the direction from the base end to the tip of the arrow indicating the Y direction is the direction from the front to the back of the page.

[0041] The front holder 210 is provided with a surrounding heat-resistant body 211. In the example shown in FIG. 4, the front holder 210 and the surrounding heat-resistant body 211 are integral. The surrounding heat-resistant body 211 contains a heat-resistant material such as a heat-resistant resin. Examples of heat-resistant materials include polypropylene (PP), polybutylene terephthalate (PBT), modified polyphenylene ether, silicone-based resin, and silica fiber. The surrounding heat-resistant body 211 may contain a single heat-resistant material exemplified herein, or may contain multiple types of heat-resistant materials exemplified herein. The melting point of the heat-resistant material is, for example, 150°C or higher, preferably 200°C or higher.

[0042] The surrounding heat-resistant body 211 surrounds at least a portion of the fuse 233 in the Y direction. Specifically, in the example shown in Fig. 4, the surrounding heat-resistant body 211 surrounds the fuse 233 in the Y direction except for the front of the fuse 233. In other words, the surrounding heat-resistant body 211 is open toward the front. Therefore, when viewed from the Y direction, the surrounding heat-resistant body 211 is substantially U-shaped or substantially N-shaped.

[0043] 4, the surrounding heat-resistant body 211 is spaced apart from the fuse 233 around the entire periphery in the Y direction of the fuse 233. Therefore, when viewed from the Y direction, a gap exists between the fuse 233 and the surrounding heat-resistant body 211, except for the area in front of the fuse 233. Therefore, when the fuse 233 melts, the fuse 233 can fall toward the gap below the fuse 233. Therefore, compared to when the fuse 233 and the surrounding heat-resistant body 211 are in contact with each other, the fuse 233 can be more easily broken by melting the fuse 233. However, the surrounding heat-resistant body 211 may be in at least partial contact with the fuse 233, except for the lower surface of the fuse 233.

[0044] A protrusion 310a is provided on the rear surface of the upper end of the front plate 310. The protrusion 310a protrudes rearward from the rear surface of the upper end of the front plate 310. When the protrusion 310a is provided, the contact area between the upper surface of the upper end of the front plate 310 and the lower surface of the front end of the upper plate 360 ​​can be increased compared to when the protrusion 310a is not provided. Therefore, when the protrusion 310a is provided, it is easier to join the upper surface of the upper end of the front plate 310 and the lower surface of the front end of the upper plate 360 ​​by a joining method such as welding compared to when the protrusion 310a is not provided.

[0045] The coated heat resistance body 311 is provided on the rear surface of the front plate 310. The coated heat resistance body 311 contains a heat-resistant material such as a heat-resistant resin. Examples of the heat-resistant material of the coated heat resistance body 311 include the materials exemplified for the surrounding heat resistance body 211. The heat-resistant material forming the coated heat resistance body 311 and the heat-resistant material forming the surrounding heat resistance body 211 may be different or the same. In one example, the coated heat resistance body 311 is attached to the rear surface of the front plate 310. Alternatively, the coated heat resistance body 311 may be formed on the rear surface of the front plate 310 by a deposition method such as vapor deposition.

[0046] The coated heat resistance body 311 covers at least a portion of the rear surface of the front plate 310. In the example shown in Fig. 4, the upper end of the coated heat resistance body 311 is located in front of the fuse 233. Therefore, the surrounding heat resistance body 211 and the coated heat resistance body 311 together surround at least a portion of the fuse 233 around the Y direction. Therefore, the impact of the fuse 233 blowing on the components around the fuse 233 can be suppressed.

[0047] 4, the coated heat-resistant body 311 exposes the underside of the protrusion 310a. This makes it easier to install the coated heat-resistant body 311 on the rear surface of the front plate 310 compared to when the coated heat-resistant body 311 covers the underside of the protrusion 310a. In one example, the gap distance between the fuse 233 and the protrusion 310a can be set to a distance that prevents debris from the fuse 233 from reaching the protrusion 310a. In this example, even if at least a portion of the protrusion 310a is exposed from the coated heat-resistant body 311, the impact of debris from the fuse 233 on the protrusion 310a can be suppressed.

[0048] In the embodiment, the surrounding heat-resistant body 211 is provided on the front holding body 210. Therefore, the number of parts of the battery module 1 can be reduced compared to when a member different from the front holding body 210 is provided to provide the surrounding heat-resistant body 211. Similarly, the coated heat-resistant body 311 is provided on the front plate 310. Therefore, the number of parts of the battery module 1 can be reduced compared to when a member different from the front plate 310 is provided to provide the coated heat-resistant body 311.

[0049] The method for at least partially surrounding the fuse 233 in the Y direction with a heat-resistant body is not limited to the method according to the embodiment.

[0050] For example, the coated heat-resistant body 311 may not be provided. In this example, for example, a portion of the surrounding heat-resistant body 211 may be located in front of the fuse 233. Alternatively, the front plate 310 itself may have heat resistance. Alternatively, the gap distance between the fuse 233 and the rear surface of the front plate 310 may be set to a distance that prevents flying debris from reaching the rear surface of the front plate 310. In this example, a heat-resistant body may not be provided in front of the fuse 233.

[0051] In the embodiment, a heat-resistant body has been described around the fuse 233 of the positive bus bar 230. However, a heat-resistant body similar to the heat-resistant body described in the embodiment may also be provided around a fuse other than the fuse 233 of the positive bus bar 230. For example, a heat-resistant body may also be provided around the fuse of the negative bus bar 230′.

[0052] FIG. 5 is a diagram showing a modification of FIG.

[0053] 5, when viewed from the Y direction, the upper end of the coated heat-resistant body 311A ​​is bent rearward at a substantially right angle. In other words, when viewed from the Y direction, the upper end of the coated heat-resistant body 311A ​​is substantially L-shaped. Therefore, the upper end of the coated heat-resistant body 311A ​​covers the lower surface of the protrusion 310a. Therefore, it is possible to more easily protect the protrusion 310a from flying debris from the fuse 233 compared to when the upper end of the coated heat-resistant body 311A ​​does not cover the lower surface of the protrusion 310a.

[0054] Although the embodiments and modifications of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various other configurations can also be adopted. [Explanation of symbols]

[0055] 1 Battery Module 10 Cell stack 20 Forward voltage detection device 20´ Rear voltage detector 30 Containment Unit 100 battery cells 100G cell group 102 Exterior materials 104 Positive electrode tab 104T Termination Positive Tab 106 Negative electrode tab 106T Negative terminal tab 108 Tabs 110 compression pad 210 Front holding body 210´ rear retainer 211 Surrounding heat-resistant body 212 Front opening 212´ rear opening 220 Forward voltage detection unit 220´ Rear voltage detector 222 Forward voltage detection wire 222´ Rear voltage detection wire 224 Front Connector 224´ Rear Connector 230 Positive bus bar 230´ Negative busbar 232 Front horizontal conductor 232´ Rear horizontal conductor 232a Fastening hole 233 Hughes 234 Front vertical conductor 234´ Rear longitudinal conductor 310 Front Plate 310a protrusion 311 Coated heat-resistant body 311A coated heat-resistant body 320 rear plate 330 Right Plate 340 Left Plate 350 Lower Plate 352 Thermally conductive adhesive 360 Upper Plate

Claims

1. A battery cell; a fuse electrically connected to the battery cell and extending in a predetermined direction; a heat resistant body at least partially surrounding the fuse around the predetermined direction; A battery module comprising:

2. A voltage detection unit electrically connected to the battery cell; A holder that holds the voltage detection unit; Further equipped with The battery module according to claim 1 , wherein at least a portion of the heat-resistant body is provided on the holder.

3. The battery pack further includes a housing for housing the battery cell. The battery module according to claim 1 , wherein the container comprises at least a portion of the heat-resistant body.

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