JP7523916B2 - Battery Module - Google Patents

Description

The present invention relates to a battery module to be mounted on a vehicle.

2. Description of the Related Art Electric vehicles, hybrid vehicles, plug-in hybrid vehicles, and the like use battery modules as a driving source.
Battery modules, which are primarily composed of multiple battery cells and restraining members such as end plates and side plates, need to be highly strong against impacts and vibrations, but they are also expected to be lightweight to ensure excellent fuel efficiency for the vehicle.

Patent Document 1 discloses an electricity storage device (battery module) that includes end plates formed by plating zinc on a metal plate molded from an iron-based metal material.
However, while the end plates disclosed in this publication ensure excellent strength, their heavy weight prevents the battery module from being made lighter.
Patent Document 2 discloses a secondary battery module in which the end plates are made of a metal material such as an aluminum alloy, a copper alloy, or SUS.
However, this publication does not specify the shape of the end plates, and does not provide a secondary battery module in which excellent strength is ensured by end plates.

JP 2015-050067 A JP 2018-081739 A

The present invention aims to provide a battery module equipped with end plates that are both strong and lightweight.

The battery module of the present invention is a battery module comprising an array body formed by arranging a plurality of battery cells, a pair of end plates which hold the array body in the array direction, and a restraint member between the pair of end plates which restrains the array body in the array direction, wherein the end plates are extruded materials having a hollow cross-sectional shape.
Since the end plates are extruded members having a hollow cross-sectional shape, the deformation strength of the end plates is improved.
Furthermore, the hollow portion reduces the weight of the end plate.

In the present invention, the end plate may have fixing portions at the upper and/or lower portions, and the restraining member may be fixed to the fixing portions.
Additionally, or in place of the above, the end plate may have a mounting member attached to the hollow end surface, and the restraining member may be fixed to the mounting member.

In the present invention, the end plate may have a flange portion on an outer surface, and the flange portion may be integrally formed with the end plate.
The outer surface of the end plate refers to the surface opposite to the arrangement direction and the inner surface facing the array.
When the flange portion is integrally formed with the end plate, the bending rigidity of the end plate in the arrangement direction of the array body is improved.
In addition, since no fastening parts are required for fastening mounting brackets or the like to the end plates, the battery module can be made lighter.

In the present invention, the end plate may have fastening holes on the outer surface, and a mounting bracket may be fastened to the fastening holes.

The battery module according to the present invention is provided with end plates that are extruded members having hollow cross-sectional shapes that are strong and lightweight, thereby ensuring the protective strength of the battery module and enabling weight reduction.
In addition, the battery module can be cooled by passing a coolant through the hollow portion of the end plate.

1A shows an example of the structure of a battery module according to the present invention (Example 1), and FIG. 1B shows an example of the structure of an end plate of Example 1. FIG. FIG. 2 shows a schematic side view of the battery module of the first embodiment. 1 shows a structural example of a battery module (Example 2). 11A and 11B show an example of the structure of an end plate according to a second embodiment, in which FIG. 11A shows the state before a mounting member is fitted, and FIG. 13 shows a structural example of a battery module (Example 3). 13A and 13B show an example of the structure of an end plate (Example 4). 13A and 13B show an example of the structure of an end plate (Example 5). 13A and 13B show an example of the structure of an end plate (Example 6). An example of how the battery module is attached to a vehicle floor, etc. is shown.

An example of a battery module according to the present invention will be described below with reference to the drawings, but the present invention is not limited thereto.
The battery module according to the present invention is characterized in that the end plates are extruded members having a hollow cross-sectional shape.
By making the end plates hollow in cross section, it is possible to suppress the increase in weight that accompanies the larger battery module, thereby achieving both lightweight and high strength.
An example of the structure of the end plate will be described below based on the embodiment, but there is no limitation on the hollow cross-sectional shape.
For example, the cross section may be shaped like a "mouth", "day", or "eye", or may even have a multi-hole cross section having a plurality of hollow portions.
In this embodiment, the positional relationship of each component will be described by setting an XYZ orthogonal coordinate system.
Hereinafter, the X direction will be referred to as the left-right direction, the Y direction will be referred to as the arrangement direction, and the Z direction will be referred to as the up-down direction.

A battery module 1 according to a first embodiment will be described with reference to FIGS.
FIG. 1( a ) shows an example of the structure of a battery module 1 of this embodiment, FIG. 1( b ) shows an example of the structure of an end plate 12 , and FIG.
This embodiment is an example of a battery module 1 in which an array 11 consisting of an array of multiple battery cells 11a is clamped in the arrangement direction between a pair of end plates 12, and a pair of restraint members 13a that restrain the array 11 are fixed in the vertical direction of the end plates 12.
FIG. 1B shows an example of the structure of the end plate 12 of this embodiment, but there are no other limitations on the end plate 12 in the present invention as long as it is an extruded material having a hollow cross-sectional shape with a plurality of hollow portions 12d.
In this embodiment, the hollow portion 12d has a cross section with four holes, but there is no limit to the number of holes.
In this embodiment, a hollow portion 12d is formed in the left-right direction perpendicular to the arrangement direction of the plurality of battery cells 11a.
Such an extrusion material having a hollow cross-sectional shape can be easily manufactured by extruding aluminum, an aluminum alloy, magnesium, or the like, and by using aluminum or the like as the material for the end plates 12, the end plates 12 can be made lighter.
The end plate 12 in this embodiment has fixing portions 12c on both the upper and lower portions 12a, 12b for fixing the restraining members 13a.
In this embodiment, the restraining member 13a is fixed using a fixing member 14 such as a bolt as shown in Figure 2, but as long as the array body 11 can be restrained in the vertical direction between a pair of end plates 12, the fixing method, the position of the fixing portion 12c, the shape of the restraining member 13a, etc. do not need to be particularly limited.
In addition, the end plate 12 of this embodiment has a flange portion 12f near the lower part of the outer surface B, and the battery module 1 is attached to a vehicle floor, a case body that houses the battery module, etc. through mounting holes 12g provided in this flange portion 12f.
In the embodiments shown in Figures 1 and 2, the position of the flange portion 12f on the outer surface B is provided near the lower part of the outer surface B of the end plate 12, but the position of this flange portion 12f can be adjusted to suit the structure and position of the vehicle floor or the mounting member 15 of the case body that houses the battery module, for example, as shown in Figure 9.
9, the upper portion of the outer surface B may be located near the upper portion of the outer surface B.
In addition, the flange portion 12f can be easily molded integrally with the end plate 12 by extrusion processing.

Second Embodiment A battery module 1 according to a second embodiment will be described with reference to FIGS.
FIG. 3 shows an example of the structure of the battery module 1 of this embodiment, FIG. 4(a) shows an example of the structure of the end plate 12 before the mounting members 12h are fitted, and FIG. 4(b) shows an example of the structure of the end plate 12 after the mounting members 12h are fitted.
This embodiment is an example of a battery module 1 in which an array 11 is sandwiched in the array direction by a pair of end plates 12, and two pairs of restraining members 13b that restrain the array 11 are fixed to the left and right of the end plates 12.
In the present embodiment, the end plate 12 has a mounting member 12h attached to a hollow end surface 12e, and the restraining member 13b is fixed via the mounting member 12h.
By making the end plate 12 have a hollow cross-sectional shape consisting of multiple hollow portions 12d, in Example 1, the restraining member 13a can be fixed directly to the upper portion 12a and/or lower portion 12b, while in Example 2, a restraining member 13b can be fixed to the hollow end face 12e.
In this embodiment, as shown in Figures 4(a) and (b), a hollow portion 12d is utilized to attach a mounting member 12h to the hollow end face 12e, and in order to fit and fix the mounting member 12h into this hollow portion 12d, a connection portion 12i is provided on the upper portion 12a, and a connection receiving portion 12j provided on the mounting member 12h is fixed with a fixing member 14.
Here, as long as the mounting member 12h can be attached to the hollow end surface 12e, the method of attachment is not particularly limited and may include bonding or adhesion.
Furthermore, there is no limitation on the shape of the mounting member 12h.
Furthermore, in this embodiment, in order to fix the restraining member 13b to the mounting member 12h, a fixing portion 12k is provided on the mounting member 12h, and the restraining member 13b is fixed with a fixing member 14, but the fixing method and the number, size, shape, etc. of the restraining members 13b do not need to be particularly limited.

An example of the structure of the battery module 1 according to the third embodiment is shown in FIG.
This embodiment is an example of a battery module 1 in which an array body 11 is clamped in the array direction between a pair of end plates 12, and restraint members 13a, 13b that restrain the array body 11 are fixed above and/or below the end plates 12, as well as in the left-right direction.
In this embodiment, the mounting member 12h is attached to the hollow end surface 12e of the end plate 12 by a method that does not use a fixing member, for example, by welding.
The method of fixing the restraining members 13a, 13b to the end plate 12 is the same as in the first and second embodiments.

Examples 4 to 6, which are structural examples of the end plate 12, are shown in FIGS.
6 to 8, (a) shows a perspective view of the end plate 12 from above, and (b) shows a perspective view of the end plate 12 from below.
The end plate 12 has an inner surface A facing the array body 11 and an outer surface B opposite to the inner surface A in the arrangement direction, and the entire outer surface B is visible in an oblique view from above, while the entire inner surface A is visible in an oblique view from below.
In the present invention, since the end plates 12 are manufactured using an extruded material, there is a high degree of freedom in the cross-sectional shape in the extrusion direction.
In this embodiment, the end plate 12 has a multi-hole cross-section with multiple hollow portions 12d, and has an approximately plate shape with the inner surface A and the outer surface B formed by parallel surfaces, so that it has the characteristic of easily restraining the ends on both sides of the array body 11.
In addition, the hollow portion 12d can be used to adjust the temperature of the battery module 1 by flowing a coolant or the like through the hollow portion 12d.
The fourth embodiment shown in FIG. 6 is an end plate 12 having a flange portion 12f near the lower portion of the outer side surface B and a mounting member 12h attached to a hollow end surface 12e.
The mounting member 12h in this embodiment has a contact surface C for contacting the hollow end face 12e, and the contact surface C is adhered or joined to the outer surface B, thereby making the mounting member 12h contact the hollow end face 12e.
In the fifth and sixth embodiments shown in Figs. 7 and 8, the end plate 12 has fastening holes 12m extending from the outer surface B to the inner surface A, and a mounting bracket or the like can be fastened to the fastening holes 12m.
The method of attaching the mounting member 12h to the hollow end surface 12e in the fifth embodiment is the same as that in the fourth embodiment.
The method of attaching the mounting member 12h to the hollow end surface 12e in the sixth embodiment is the same as that in the second embodiment.

Reference Signs List 1 Battery module 11 Array 11a Battery cell 12 End plate 12a Upper portion 12b Lower portion 12c Fixing portion 12d Hollow portion 12e Hollow end surface 12f Flange portion 12h Mounting member 12m Fastening hole 13a Restraining member 13b Restraining member A Inner surface B Outer surface C Contact surface

Claims (3)

A battery module comprising: an array formed by arranging a plurality of battery cells; a pair of end plates that sandwich the array in an array direction; and a restraining member that restrains the array in the array direction between the pair of end plates,
The end plate is an extruded member having a hollow cross-sectional shape , an attachment member is provided in contact with an end surface of the hollow plate, and the restraining member is fixed to the attachment member. The end plate has a flange portion on an outer surface,
2. The battery module according to claim 1 , wherein the flange portion is integrally formed with the end plate. The end plate has a fastening hole on an outer surface thereof,
The battery module of claim 1 , wherein a mounting bracket is fastened to the fastening hole.

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