Battery module

Abstract

The invention provides a battery module capable of improving cooling efficiency of end battery cells. A battery module according to the present invention is provided with: a battery stack in which a plurality of battery cells are stacked; a cooling flow path provided on the lower side of the cell stack; and a cooling duct disposed on the inlet side of the cooling flow path. The cross-sectional area of the cooling duct is larger than the cross-sectional area of the cooling flow path.

Description

Technical Field

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

[0002] Patent Document 1 discloses a structure in which a cooling flow path is provided between an end plate and a battery cell in a battery module.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2020-119884

[0004] In the structure disclosed in Patent Document 1, there is room for improvement in the efficiency of transferring the refrigerant to the gap between the end plate and the end battery cell (battery cell arranged at the end). Summary of the invention

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a battery module capable of improving the cooling efficiency of end battery cells.

[0006] The battery module involved in the present invention comprises: a battery stack formed by stacking a plurality of battery cells; a cooling flow path provided on the lower side of the battery stack; and a cooling pipe arranged on the inlet side of the cooling flow path, wherein the cross-sectional area of ​​the cooling pipe is larger than the cross-sectional area of ​​the cooling flow path.

[0007] According to the present invention, a large amount of coolant can be sent to the side surfaces of the end plates (surfaces in the stacking direction of the battery cells), and thus the cooling efficiency of the end battery cells can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a plan view showing the structure of a battery module according to the embodiment.

[0009] Figure 2 It is a cross-sectional view showing the configuration of a battery module according to the embodiment when viewed from the side.

[0010] Figure 3 It is a cross-sectional view showing the configuration of a first modified example of the battery module according to the embodiment when viewed from the side.

[0011] Figure 4 It is a cross-sectional view showing the configuration of a second modified example of the battery module according to the embodiment when viewed from the side. DETAILED DESCRIPTION

[0012] A battery module according to an embodiment of the present invention will be described with reference to the accompanying drawings. In addition, the constituent elements in the following embodiments include elements that can be easily replaced by those skilled in the art or are substantially the same.

[0013] Regarding the configuration of the battery module according to the embodiment, Figure 1 and Figure 2 The battery module according to the embodiment is mounted on a vehicle such as a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), or an electric vehicle (BEV).

[0014] Figure 1 FIG. 1 is a top view showing a battery module according to an embodiment of the present invention with the upper cover of the battery case removed. Figure 2 is a cross-sectional view showing the structure of the battery module according to the embodiment when viewed from the side. Figure 1 and Figure 2 In FIG. 1 , W indicates the width direction of the battery module, L indicates the length direction of the battery module, and H indicates the height direction of the battery module. In addition, the hollow arrows shown in the figure indicate the flow direction of the coolant (coolant path).

[0015] The battery module 1 includes a battery stack 11 , a battery case 12 , a cooling duct 13 , a cooling flow path 14 , an end plate 15 , and a sealing member 16 .

[0016] The battery stack 11 is formed by stacking a plurality of battery cells 111. An elastic body 112 is sandwiched between each battery cell 111. In addition, the direction in which the plurality of battery cells 111 are stacked (hereinafter referred to as the "stacking direction") is the same direction as the width direction W of the battery module 1. A cooling flow path 14 consisting of a predetermined space is provided on the lower side of the battery stack 11. The inlet side (opening side) of the cooling flow path 14 is connected to the cooling pipe 13. The refrigerant (such as air, etc.) introduced from the cooling pipe 13 is thereby supplied to the gaps between each battery cell 111 of the battery stack 11, etc.

[0017] The battery case 12 is used to accommodate the battery stack 11 and the end plate 15. The battery case 12 is composed of an upper cover and a lower case (not shown). In addition, an opening 121 is provided at the lower portion of the battery case 12 where the cooling pipe 13 is installed. The opening 121 is used to send the refrigerant introduced from the cooling pipe 13 into the cooling flow path 14.

[0018] The cooling duct 13 is used to introduce the refrigerant into the cooling flow path 14. The cooling duct 13 is disposed on the inlet side of the cooling flow path 14. The cooling duct 13 is attached to the battery case 12 so as to communicate with the opening 151 of the end plate 15 and the cooling flow path 14.

[0019] The end plates 15 are components for holding the battery stack 11 in the stacking direction. Figure 2 Only the end plate 15 on the inlet side of the cooling flow path 14 is shown in the figure, but an end plate is also provided on the inner side of the cooling flow path 14.

[0020] The end plate 15 is disposed at a position opposite to the end battery cell (battery cell 111 disposed at the end). In addition, an opening 151, such as a notch, is provided at the central lower portion of the end plate 15. The opening 151 is used to send the refrigerant into the battery case 12. In addition, both sides of the opening 151 are portions mounted (seated) on the inner side of the battery case 12, and therefore are not open. Therefore, no cooling flow path is provided in this portion.

[0021] The sealing member 16 is used to prevent air leakage from the contact surface between the end plate 15 and the battery case 12. The sealing member 16 is provided between the end plate 15 and the battery case 12 and is located above the opening 121. In addition, in the battery module 1, the contact surface between the end plate 15 and the battery case 12 on which the sealing member 16 is provided is not provided with a cooling flow path, and a cooling flow path is provided only between the end plate 15 and the end battery cell.

[0022] in addition, Figure 2 The figure shown by the bubble frame is a front view of the end plate 15 when viewed from the end battery cell side. In this embodiment, as shown by the arrow in the figure, the refrigerant introduced from the opening 151 in the lower center of the end plate 15 flows upward from the lower side of the end plate 15, and then flows to the left and right branches near the center. As a result, the refrigerant flows along the left and right inner surfaces (side surfaces) of the battery case 12. That is, in the battery module 1, the cooling flow path between the end plate 15 and the end battery cell is a T-shaped flow path.

[0023] Here, in a conventional battery module, for example, a sealing member for preventing air leakage is provided at the position of the opening 151 of the present embodiment, so there is a problem that the coolant is difficult to flow in the gap between the end plate and the end battery cell.

[0024] In addition, in the existing battery module, the cross-sectional area of ​​the cooling flow path needs to be adjusted, for example, the inlet side (opening side) is made wider and the inner side (opposite side) is made narrower. Therefore, if the cross-sectional area required for the flow of the refrigerant is to be ensured on the inner side of the cooling flow path, the cross-sectional area on the inlet side of the cooling flow path increases, and the size of the battery case increases.

[0025] Therefore, in this embodiment, if Figure 2 As shown, an opening 121 is provided at the lower portion of the battery case 12 and an opening 151 is provided at the lower central portion of the end plate 15 , and the cross-sectional area A of the cooling duct 13 is larger than the cross-sectional area B of the cooling flow path 14 .

[0026] That is, in this embodiment, the cross-sectional area A of the cooling duct 13 on the inlet side of the cooling flow path 14 is enlarged compared to the conventional battery module, and is communicated with the opening 151. Figure 2 As shown by arrow F, more refrigerant can be transported to the side surface of the end plate 15 (the surface in the stacking direction of the battery cells 111), thereby improving the cooling efficiency of the end battery cells. In addition, the size of the battery case 12 can be prevented from increasing, and miniaturization can be achieved.

[0027] Next, the first modification example will be described. Figure 3 The structure of the first variant of the battery module according to the embodiment will be described. This figure is a cross-sectional view showing the structure of this variant when viewed from the side. In addition, the top view and the Figure 1 same.

[0028] The battery module 1A includes a battery stack 11 , a battery case 12 , a cooling duct 13 , a cooling flow path 14 , an end plate 15 , and a sealing member 16 , similarly to the above-described battery module 1 .

[0029] In the battery module 1A, an opening 121 such as a notch is provided at the lower portion of the battery case 12. In the battery module 1A, an opening 151 is provided at the lower center portion of the end plate 15. In the battery module 1A, similarly to the battery module 1, the cross-sectional area A of the cooling duct 13 is larger than the cross-sectional area B of the cooling flow path 14.

[0030] Furthermore, in the battery module 1A, for example, by changing the structure (shape) of the end plate 15, as shown in FIG. Figure 3 As shown in the bubble frame, the refrigerant introduced from the opening 151 at the lower center of the end plate 15 is branched to the upper side in addition to the left and right sides. That is, in the battery module 1A, the cooling flow path between the end plate 15 and the end battery cell is a T-shaped and I-shaped flow path. As a result, in addition to the inner surfaces (side surfaces) on the left and right sides of the battery shell 12, the refrigerant can also flow on the inner surface (top surface) on the upper side, thereby further improving the cooling efficiency of each battery cell 111.

[0031] Next, the second modification example will be described. Figure 4 The second modification of the battery module according to the embodiment will be described. This figure is a cross-sectional view showing the configuration of this modification when viewed from the side. In addition, the top view when the configuration of this modification is viewed from above is similar to the top view when viewed from above. Figure 1 same.

[0032] The battery module 1B includes a battery stack 11 , a battery case 12 , a cooling duct 13 , a cooling flow path 14 , an end plate 15 , and a sealing member 16 similarly to the battery module 1 described above.

[0033] In the battery module 1B, an opening 151 such as a notch is provided at the center of the end plate 15. In the battery module 1B, an opening 121 is provided at a position corresponding to the opening 151 of the end plate 15 at the center of the battery case 12.

[0034] That is, in the battery module 1B, an opening 151 is provided at a position other than the lower center of the end plate 15, and an opening 121 is provided at a position other than the lower part of the battery case 12. In addition, the position and number of the openings 121 and 151 are not particularly limited, and can be adjusted according to the required cooling capacity. In addition, in the battery module 1B, similarly to the above-mentioned battery modules 1 and 1A, the cross-sectional area A of the cooling duct 13 is larger than the cross-sectional area B of the cooling flow path 14.

[0035] Furthermore, in the battery module 1B, as Figure 4 As shown in the bubble frame, the refrigerant introduced from the central opening 151 of the end plate 15 is branched to the left and right sides of the upper side and the left and right sides of the lower side. That is, in the battery module 1B, the cooling flow path between the end plate 15 and the end battery cell is a cross-shaped flow path. This allows the refrigerant to flow along the inner surface (side) of the left and right sides of the battery case 12 in multiple paths, thereby further improving the cooling efficiency of the battery cell 111.

[0036] According to the battery module according to the above-described embodiment, a large amount of coolant can be sent to the side surfaces of the end plates 15 (surfaces in the stacking direction of the battery cells), thereby improving the cooling efficiency of the end battery cells.

[0037] Those skilled in the art can easily derive further effects and variations. Therefore, the broader aspects of the present invention are not limited to the specific details and representative embodiments shown and described above. Therefore, various changes can be made without departing from the spirit or scope of the general concept of the invention defined by the technical solution and its equivalents.

Claims

1. A battery module, characterized in that: have: A battery stack is made up of multiple battery cells stacked together; A cooling flow path is provided at the lower side of the battery stack; and A cooling pipe is arranged at the inlet side of the cooling flow path, The cross-sectional area of ​​the cooling pipe is larger than the cross-sectional area of ​​the cooling flow path.

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