JP2022118614A - battery module - Google Patents

Abstract

To provide a battery module with improved cooling performance of a circuit board.SOLUTION: A battery module 100 comprises: a battery cell 20; a heat sink 30 in contact with the battery cell; a circuit board 40; and a battery case 10 which houses the battery cell, the heat sink, and the circuit board. The battery case has an opening 2 which brings the inside of the battery case into communication with the outside thereof. The heat sink is provided with a guide part 36 which guides an air flow from the opening to the circuit board. In the battery module, a pair of electrode tabs 22 extend in a first direction X from an end of an outer package of the battery cell. The circuit board may be located between the pair of electrode tabs.SELECTED DRAWING: Figure 3

Description

This specification discloses a technology related to a battery module.

Patent Literature 1 discloses a battery module in which battery cells and deformation prevention plates are accommodated in a battery case. In Patent Document 1, a plurality of battery cells are stacked and accommodated in a battery case, and a deformation prevention plate having heat dissipation properties is arranged between the battery cells (Patent Document 1: FIG. 2, etc.). Patent Document 1 also discloses an example in which a circuit board (battery protection circuit) is arranged in a battery case (Patent Document 1: FIG. 9).

WO2007/043392A1

In the battery module of Patent Literature 1, the heat generated in the battery cells is radiated by the radiator plate (deformation prevention plate). However, the heat generated in the circuit board cannot be sufficiently dissipated. In particular, when the battery cells, the heat sink, and the circuit board are housed in a common battery case, the battery cells and the heat sink impede the circulation of air in the battery case, and the heat dissipation (cooling) of the circuit board is reduced. The present specification provides a technique for realizing a battery module with improved cooling of the circuit board.

The first technology disclosed in this specification is a battery module. The battery module may include battery cells, a heat sink in contact with the battery cells, a circuit board, and a battery case that houses the battery cells, the heat sink, and the circuit board. In this battery module, the battery case may be provided with an opening that communicates the inside and outside of the battery case, and the heat sink may be provided with a guide portion that guides air flow from the opening toward the circuit board.

A second technique disclosed in this specification is the battery module of the first technique, wherein a pair of electrode tabs extends in a first direction from an end portion of the exterior of the battery cell, and a circuit board includes a pair of It may be located between the electrode tabs.

A third technique disclosed in this specification is the battery module of the second technique, wherein the opening provided in the battery case is provided in a second direction intersecting the first direction, and the guide portion is , may be formed in a straight line connecting the end face in the first direction and the end face in the second direction of the heat sink.

A fourth technique disclosed in the present specification is the battery module according to any one of the first to third techniques, wherein a pair of openings provided in the battery case are provided on opposite surfaces of the battery case. The radiator plate may have a guide portion for each of the pair of openings that guides the flow of air from the opening toward the circuit board.

A fifth technique disclosed in the present specification is the battery module of the fourth technique, wherein the battery module is used to supply electric power to a mobile object, and the pair of openings are arranged in the traveling direction of the mobile object. It may be arranged to be positioned forward and rearward.

A sixth technique disclosed in this specification is the battery module according to any one of the first to fifth techniques, wherein the end surface of the battery cell opposite to the end surface facing the circuit board is a heat sink. may be included in the same plane as the end face opposite to the end face facing the circuit board.

A seventh technology disclosed in the present specification is a battery module according to any one of the first to sixth technologies, wherein a plurality of battery cells are stacked and arranged in a battery case, and each battery cell Heat sinks may be arranged between them, and all the heat sinks may be provided with guides.

According to the first technique, air that has flowed into the battery case from outside the battery case through the opening can be efficiently moved toward the circuit board. As a result, the cooling efficiency of the circuit board is improved, and the temperature rise in the battery case can be suppressed.

According to the second technique, the space (typically dead space) between the pair of electrode tabs can be effectively utilized. That is, it is not necessary to secure a space in the battery case only for arranging the circuit board, and the size of the battery case (the size of the battery module) can be reduced.

According to the third technique, the guide portions can be provided at positions corresponding to the corners of the battery cells. In other words, the heat dissipation of the battery cells is reduced by contacting the central portion of the battery cell that generates a large amount of heat with the heat sink and keeping the corners of the battery cell with a relatively low heat value out of contact with the heat sink (providing a guide portion). It is possible to efficiently cool the circuit board while ensuring.

According to the fourth technique, the air that has flowed into the battery case can be guided to the circuit board, and the air around the circuit board can be guided to the outside of the battery case. Since the air heated by the circuit board is efficiently discharged to the outside of the battery case, it is possible to further suppress the temperature rise in the battery case.

According to the fifth technique, as the moving body moves, the air outside the battery case can be introduced into the battery case, and the air inside the battery case can be discharged outside the battery case. The circuit board can be cooled without using a device for sending air into the battery case (or discharging air out of the battery case).

According to the sixth technique, since the battery cells and the heat sink are positioned in one direction, misalignment of the battery cells and the heat sink can be prevented when manufacturing the battery module.

According to the seventh technique, a large air flow path area is ensured, a large amount of air can be sent to the circuit board, and the circuit board can be efficiently cooled.

The perspective view of the external appearance of a battery module is shown. The perspective view of the internal structure of a battery module is shown. The top view for demonstrating the internal structure of a battery module is shown. The top view for demonstrating the internal structure of a battery module is shown.

(battery module)
The battery module 100 will be described with reference to FIG. The battery module 100 is mounted on a moving object (not shown) such as a flying object such as a manned aircraft or an unmanned aerial vehicle (drone), or a vehicle such as an automobile or a motorcycle. The battery module 100 supplies electric power to motors, electronic devices, and the like mounted on a moving object. The battery module 100 includes a battery case 10 , a plurality of battery cells 20 housed in the battery case 10 , and a plurality of radiator plates 30 housed in the battery case 10 . Although the details will be described later, the battery case 10 also accommodates a circuit board 40 (see FIG. 2) for interrupting the energization of the battery cells 20 when an abnormality occurs in the battery module 100 .

The battery case 10 includes an accommodating portion 8 in which the battery cells 20 are arranged, and a lid portion 6 that closes an opening in the upper portion (+Z direction) of the accommodating portion 8 . A pair of openings 2 are provided on both sides of the housing portion 8 in the front-rear direction (Y direction). The pair of openings 2 communicate the inside and outside of the battery case 10 (accommodating portion 8). A part of the battery cells 20 and a part of the heat sink 30 arranged in the battery case 10 are exposed to the outside through the opening 2 (visible from the outside). The battery case 10 (accommodating portion 8) is provided with a connector (not shown) to which wiring of an external device (motor, electronic device, etc.) is connected. In the following description, the Z direction may be referred to as the up-down direction, the Y direction as the front-rear direction, and the X direction as the left-right direction. Note that the battery module 100 is mounted on a moving body such that the front-rear direction is positioned forward and rearward in the traveling direction of the moving body.

The internal structure of the battery module 100 will be described with reference to FIG. FIG. 2 shows a view of the battery case 10 with the side portions of the lid portion 6 and the housing portion 8 removed. As shown in FIG. 2, the battery cells 20 and the heat sinks 30 are arranged alternately in the vertical direction. In other words, the radiator plate 30 is arranged between the battery cells 20 adjacent to each other in the vertical direction. The radiator plate 30 is in contact with the surface of the battery cell 20 and radiates heat generated in the battery cell 20 . The shape (exterior shape) of the battery cell 20 is substantially rectangular. On the other hand, the shape of the radiator plate 30 is an octagon obtained by cutting off corners (four corners) of a rectangle. Therefore, at the corners of the battery cells 20, there is no radiator plate 30 between the battery cells 20 adjacent in the vertical direction, and gaps are provided. Details of the heat sink 30 will be described later.

Each battery cell 20 has a pair of electrode tabs 22 . A pair of electrode tabs 22 extend in the same direction (+X direction) from the exterior of the battery cell 20 . The pair of electrode tabs 22 extends so as to cross (perpendicularly) the direction (Y direction) connecting the pair of openings 2 . In other words, the pair of openings 2 are provided in the direction (Y direction) intersecting the direction (+X direction) in which the pair of electrode tabs 22 extend. The X direction is an example of a first direction, and the Y direction is an example of a second direction. The pair of electrode tabs 22 extends in the direction in which the connector is provided. Also, in each battery cell 20, the pair of electrode tabs 22 are provided with an interval in the Y direction (front-rear direction). As described above, the circuit board 40 is accommodated inside the battery case 10 (accommodating portion 8). The circuit board 40 is arranged between the pair of electrode tabs 22 . Therefore, when the battery module 100 is observed from the Y direction, part of the circuit board 40 overlaps the pair of electrode tabs 22 . The circuit board 40 is connected to the pair of electrode tabs 22 by wiring (not shown), and is a protection circuit that cuts off current when the battery cell 20 malfunctions.

Features of the heat sink 30 will be described with reference to FIGS. 3 and 4. FIG. 3 shows a state in which the battery cells 20 appear on the top surface, and FIG. 4 shows a state in which the radiator plate 30 appears on the top surface. The battery cell 20 is substantially rectangular, and the heat sink 30 is substantially octagonal. The heat sink 30 can also be regarded as a substantially rectangular shape with four corners cut off. Of the left-right direction (X direction) end faces of the heat sink 30, the length of the end face 33 (+X direction end face) facing the circuit board 40 is shorter than the length of the end face 23 of the battery cell 20 facing the circuit board 40. . The length of the end face 35 of the heat sink 30 opposite to the end face 33 (the end face in the -X direction) is shorter than the length of the end face 25 of the battery cell 20 opposite to the end face 23 . The length of both end surfaces 34 of the heat sink 30 in the front-rear direction (Y direction) is shorter than the length of both end surfaces 24 of the battery cell 20 in the front-rear direction. Moreover, the length of the heat sink 30 in the left-right direction (the distance between the end faces 33 and 35) is shorter than the length of the battery cell 20 in the left-right direction (the distance between the end faces 23 and 25). The length of the heat sink 30 in the front-rear direction (the distance between the end faces 34, 34) is longer than the length of the battery cell 20 in the front-rear direction (the distance between the end faces 24, 24).

In the battery module 100, the -X direction end faces (end faces 25, 35) of the front-rear and left-right direction end faces of the heat sink 30 and the battery cells 20 are positioned so as to be included in the same plane. In other words, the end face 25 does not protrude from the end face 35 in the -X direction, and the end face 35 does not protrude from the end face 25 in the -X direction. As noted above, the distance between end faces 33,35 is less than the distance between end faces 23,25. Therefore, the end face 23 of the battery cell 20 protrudes from the end face 33 of the heat sink 30 in the +X direction. By aligning the end face 25 of the battery cell 20 and the end face 35 of the heat sink 30 so as to be included in the same plane, the battery cell 20 and the heat sink 30 can be easily positioned when assembling the battery module 100. . Note that both end surfaces 34 of the heat sink 30 protrude with respect to both end surfaces 24 of the battery cells 20 in the front-rear direction.

The heat sink 30 includes a linear first inclined portion 36 connecting the end surfaces 33 and 34 and a linear second inclined portion 38 connecting the end surfaces 34 and 35 . The first inclined portion 36 is an example of a guide portion. The first inclined portion 36 and the second inclined portion 38 are provided on both sides of the radiator plate 30 in the front-rear direction. Also, the first inclined portion 36 and the second inclined portion 38 are provided on all the heat sinks 30 (see also FIG. 2). Outside the inclined portions 36 and 38 (at the four corners of the battery cell 20), the radiator plate 30 does not exist between the vertically adjacent battery cells 20 and 20. As shown in FIG. That is, at the four corners of the battery cell 20, gaps are provided between the vertically adjacent battery cells 20,20.

As described above, the battery module 100 is mounted on a moving body such that the front-rear direction (Y direction) is located forward and rearward in the moving direction of the moving body. That is, the battery module 100 is mounted on the moving body such that the pair of openings 2 are positioned forward and rearward in the moving direction of the moving body. Therefore, when the moving object moves, air flows into the battery case 10 through one opening 2 and is discharged out of the battery case 10 through the other opening 2 . Air hardly flows into the battery case 10 from the outside of the battery case 10 at the opening 2b of the opening 2 facing the end surface 34 of the heat sink 30 . This is because the heat sink 30 exists between the battery cells 20, 20 in the opening 2b. Movement of air into and out of the battery case 10 is performed at an opening portion 2 a of the opening 2 that faces the first inclined portion 36 .

The air that has flowed into the battery case 10 from the opening 2 (opening portion 2 a ) moves along the first inclined portion 36 through the gaps between the battery cells 20 , 20 to the circuit board 40 . The first inclined portion 36 functions as a guide portion that guides the flow of air from the opening 2 toward the circuit board 40 . As described above, the first inclined portions 36 are provided on both sides of the radiator plate 30 in the front-rear direction. That is, for each of the pair of openings 2, the radiator plate 30 has a guide portion that guides the flow of air from the opening 2 toward the circuit board 40 (or guides the flow of air from the circuit board 40 toward the opening 2). It has a guide part). Therefore, one of the first inclined portions 36 guides the air from the opening 2 to the circuit board 40 and the other guides the air from the circuit board 40 to the opening 2 .

(Advantages of Battery Module 100)
In the battery module 100, since the heat sink 30 is provided with the first inclined portion 36 (guide portion), the heat is directed from the outside of the battery case 10 toward the circuit board 40 and from the circuit board 40 toward the outside of the battery case 10. , can guide the air flow. As a result, the circuit board 40 can be efficiently cooled. By providing the first inclined portions 36 on both sides of the heat sink 30 in the front-rear direction, the heat generated in the circuit board 40 is efficiently discharged to the outside of the battery case 10, and the temperature rise in the battery case 10 is suppressed. By suppressing the temperature rise in the battery case 10, the occurrence of abnormality in the battery cells 20 is suppressed.

The first inclined portion 36 is provided at a position corresponding to the corner of the battery cell 20 . That is, heat is not radiated from the corners of the battery cells 20 by the radiator plate 30 . When the battery cell 20 generates heat, the heat generation temperature is higher at the central portion than at the corner portions of the battery cell 20 . In the battery module 100, the heat generated in the battery cells 20 is ensured by the heat dissipation plate 30 in the portion where the heat generation of the battery cells 20 is large, and the heat dissipation by the heat dissipation plate 30 is omitted in the portion where the heat generation of the battery cells 20 is small. can efficiently dissipate heat. Moreover, in the battery module 100 , all the heat sinks 30 are provided with the first inclined portions 36 . That is, gaps are formed at all the corners between the battery cells 20, 20 that are adjacent in the vertical direction. A large air flow path area can be secured, and the cooling efficiency of the circuit board 40 can be enhanced.

In the battery module 100 , a pair of electrode tabs 22 extend in the same direction (+X direction) from the exterior of the battery cell 20 , and the circuit board 40 is arranged between the pair of electrode tabs 22 . As a result, the components (battery cells 20, heat sink 30, and circuit board 40) inside the battery case 10 are arranged efficiently, and the space inside the battery case 10 can be effectively utilized. As a result, the size of the battery module 100 can be reduced.

The battery module 100 is mounted on a moving object so that the surfaces (surfaces in the front-rear direction) on which the pair of openings 2 are provided are located forward and rearward in the traveling direction of the moving object. Therefore, as the moving object moves, air flows into the battery case 10 through one opening 2 and is discharged out of the battery case 10 through the other opening 2 . Air can be introduced into the battery case 10 without providing a device (such as a fan) for sending air into the battery case 10 .

(Other embodiments)
The gist of the technology disclosed in this specification is to provide an opening in the battery case that communicates the inside and outside of the battery case, and to provide a guide portion that guides the flow of air from the opening toward the circuit board in the heat sink. Therefore, among the features of the battery module described in the above embodiments, the features other than the above-described gist are not necessarily essential. For example, the position where the circuit board is arranged does not have to be between the pair of electrode tabs. Also, the pair of electrode tabs may extend in different directions from the ends of the exterior of the battery cell. The position where the circuit board is arranged and the direction in which the electrode tab extends (the position where the battery tab is arranged) can be appropriately changed according to the shape of the space in which the battery module is arranged (that is, the outer shape of the battery module). Similarly, the position where the opening is provided in the battery case, the position where the guide section is provided in the heat sink, the shape of the guide section, and the like can be appropriately changed as necessary.

An opening may be provided only on one surface of the battery case, and only one guide portion may be formed on the heat sink. Even in this case, the air outside the battery module can be efficiently supplied to the circuit board by providing the guide portion. Further, among the heat sinks stacked in the vertical direction, some of the heat sinks may be provided with the guide portions, and the other heat sinks may not be provided with the guide portions. For example, if the thickness of the circuit board (the distance in the vertical direction) is thinner than the thickness of the laminate of the battery cells and the heat sink, only the heat sink corresponding to the thickness of the circuit board is provided with guides, It is not necessary to provide a guide portion on the portion of the heat sink that does not correspond to the thickness of the plate.

In addition, the direction in which the battery modules are arranged with respect to the moving object can be arbitrarily changed. In other words, the opening of the battery case does not have to be located forward and backward in the traveling direction of the moving body. For example, if an air flow path is formed in the moving body that flows in a direction different from the traveling direction, or if a fan or the like for circulating air is provided in the moving body, the battery case should be designed according to the air flow path. The orientation of the opening may be adjusted.

Although the embodiments of the present invention have been described in detail above, they are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. In addition, the technical elements described in this specification or in the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the techniques exemplified in this specification or drawings achieve multiple purposes at the same time, and achieving one of them has technical utility in itself.

2: Battery case opening 10: Battery case 20: Battery cell 30: Radiator plate 36: Guide part 40: Circuit board 100: Battery module

Claims (7)

a battery cell;
a heat sink in contact with the battery cell;
a circuit board;
a battery case that accommodates the battery cell, the heat sink, and the circuit board,
The battery case has an opening that communicates the inside and outside of the battery case,
The battery module, wherein the radiator plate is provided with a guide portion that guides air flow from the opening toward the circuit board. The battery module according to claim 1,
a pair of electrode tabs extending in a first direction from an end of the exterior of the battery cell;
A battery module, wherein a circuit board is disposed between a pair of electrode tabs. The battery module according to claim 2,
The opening is provided in a second direction that intersects the first direction,
The battery module, wherein the guide portion is formed in a straight line connecting the end surface of the heat sink in the first direction and the end surface in the second direction. The battery module according to any one of claims 1 to 3,
A pair of openings are provided on opposite sides of the battery case,
The battery module, wherein the radiator plate has a guide portion for each of the pair of openings that guides air flow from the opening toward the circuit board. The battery module according to claim 4,
The battery module is used to supply electric power to a mobile body, and is arranged such that the pair of openings are positioned forward and rearward in a traveling direction of the mobile body. The battery module according to any one of claims 1 to 5,
A battery in which an end face of the battery cell opposite to the end face facing the circuit board is included in the same plane as an end face of the heat sink opposite to the end face facing the circuit board. module. The battery module according to any one of claims 1 to 6,
A plurality of battery cells are stacked and arranged in the battery case,
A heat sink is placed between each battery cell,
A battery module in which all heat sinks are provided with guides.

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