Battery case

Abstract

The utility model relates to a battery shell, which is used for accommodating a plurality of battery stacks and is provided with a shell main body, a plurality of refrigerant passages, a plurality of heat exchangers, a plurality of heat exchangers, a plurality of heat exchangers, a plurality of heat exchangers, a plurality of heat exchangers and a plurality of heat exchangers, and is characterized in that the shell main body is provided with a plurality of refrigerant passages which are formed to enable refrigerants to flow towards each of the plurality of battery stacks; and a refrigerant branching section configured so as to distribute the refrigerant to the plurality of refrigerant passages. The refrigerant branch portion can be attached to and detached from the housing main body. As a result, it is possible to uniformly cool the plurality of cell stacks housed in the cell case.

Description

Technical Field

[0001] The utility model relates to a battery casing for accommodating a plurality of battery stacks. Background Art

[0002] Japanese Patent Application Laid-Open No. 2022-100813 discloses a so-called stacked electrode body formed by alternately stacking a plurality of positive electrodes and a plurality of negative electrodes with separators interposed therebetween.

[0003] Regarding the cooling of multiple battery stacks housed in a battery housing, the inventors of the present application first recognized the existence of the following technical problem: Depending on the positional relationship between the cooling device and the battery housing, the multiple passages through which the refrigerant for cooling the multiple battery stacks flows have different refrigerant flow rates allocated to them. In order to achieve increased battery output and longer life, it is desirable to evenly cool each battery stack in operation. However, in the case where there are differences in the refrigerant flow rates allocated to each refrigerant passage as described above, it is difficult to say that each battery stack is evenly cooled. This state is not optimal for increased battery output and longer life. Utility Model Content

[0004] One object of the present invention is to provide a technology that can solve the technical problem of uneven cooling of multiple battery stacks.

[0005] One aspect of the utility model relates to a battery housing for accommodating a plurality of battery stacks. The battery housing comprises: a housing body having a plurality of refrigerant passages configured to allow refrigerant to flow to each of the plurality of battery stacks; and a refrigerant branching portion configured to distribute refrigerant to the plurality of refrigerant passages. The refrigerant branching portion can be detached from the housing body.

[0006] According to one aspect of the utility model, the refrigerant branch portion is formed to be detachable relative to the housing body. The shape of the refrigerant branch portion can be optimized according to the positional relationship between the cooling device and the battery housing. That is, the shape of the refrigerant branch portion can be designed to cool multiple battery stacks as evenly as possible. This helps to improve the output and prolong the life of the battery.

[0007] Furthermore, the refrigerant branching part can be manufactured independently of the housing body, which means that the housing body of the same shape can be applied to various situations regardless of the positional relationship between the cooling device and the battery housing. Therefore, compared with the case where the refrigerant branching part is integrated with the housing body, it helps to reduce the cost of parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a schematic diagram showing an example of a battery pack.

[0009] Figure 2A and Figure 2B A diagram is a diagram used to represent a technical problem and its solution.

[0010] FIG. 3A to FIG. 3C It is a schematic diagram which shows an example of the battery case which concerns on embodiment of this invention. DETAILED DESCRIPTION

[0011] The embodiments of the present invention will be described with reference to the accompanying drawings.

[0012] Figure 1 1 is a schematic diagram showing an example of a battery pack 1. The battery pack 1 is used as a power source for electric vehicles such as BEV, PEV, and HEV. The battery pack 1 includes a battery case 11 and a cooling device 12.

[0013] The battery case 11 includes a case body 111 and a refrigerant branching portion 112 .

[0014] A plurality of battery stacks 113 are housed (arranged) in the housing body 111. Each battery stack 113 is formed by integrating a plurality of battery cells. The battery cell is a secondary battery capable of charge and discharge, such as a lithium-ion secondary battery.

[0015] The housing body 111 has a plurality of branch refrigerant passages 1111. Refrigerant 2 for cooling the plurality of battery stacks 113 flows into each of the plurality of branch refrigerant passages 1111. That is, the plurality of branch refrigerant passages 1111 are provided for each of the plurality of battery stacks 113. The refrigerant 2 is, for example, air.

[0016] The refrigerant branching portion 112 is a structure for distributing the refrigerant 2 from the cooling device 12 described later to a plurality of branched refrigerant passages 1111 .

[0017] Figure 1 The cooling device 12 shown has a cooling device 121 and a main refrigerant passage 122. The refrigerant 2 generated in the cooling device 121 flows into the branch refrigerant passages 1111 in the battery case 11 through the main refrigerant passage 122. When the refrigerant 2 flows into the branch refrigerant passages 1111, the refrigerant 2 hits the refrigerant branching portion 112, whereby the refrigerant 2 changes direction from the main refrigerant passage 122 and is distributed to each branch refrigerant passage 1111.

[0018] Regarding the battery case 11 with the cooling device 12 described above, the inventors of the present application first recognized the following technical problem: the flow rate of the refrigerant 2 distributed to the plurality of branch refrigerant passages 1111 differs depending on the positional relationship between the cooling device 121 and the battery case 11 .

[0019] To improve the output and extend the life of the battery, it is preferable to uniformly cool the plurality of battery stacks 113. However, if the flow rates of the coolant 2 distributed to the plurality of branch coolant passages 1111 differ as described above, it is difficult to say that the plurality of battery stacks 113 are uniformly cooled.

[0020] Figure 2A Indicates the state where the cooling of the plurality of battery stacks 113 is uneven. Figure 2A In this case, the battery stack 113-1 is located in the direction in which the refrigerant 2-1A generated in the cooling device 121 advances straightly. Therefore, the flow rate of the refrigerant 2-1A flowing to the battery stack 113-1 is greater than the flow rate of the refrigerant 2-2A flowing to the battery stack 113-2. As a result, the battery stack 113-1 is cooled more strongly than the battery stack 113-2.

[0021] As one of the measures to address the above-mentioned technical problem of uneven cooling of the battery stack, there is a method of changing the shape of the coolant branching portion 112 .

[0022] For example, Figure 2B In the case of Figure 2A In this case, the coolant 2-1B flowing toward the battery stack 113-1 is larger than that flowing toward the battery stack 113-1. Figure 2A On the other hand, the amount of refrigerant 2-2B flowing to the battery stack 113-2 is less than that of the refrigerant 2-1A. Figure 2A More refrigerant 2-2A is present in the Figure 2B Such a structure, with Figure 2A Compared with the state of FIG. 1 , the amount of refrigerant flowing into the battery stack 113 - 1 and the battery stack 113 - 2 is close to being uniform.

[0023] However, the positional relationship between the cooling device 121 and the battery case 11 varies depending on the installation situation, so it is necessary to install a new battery case 11 having a refrigerant branching portion 112 of a shape suitable for each situation each time. This increases component costs, so the above measures are limited in effectiveness.

[0024] The above description mentions two technical problems: uneven cooling of multiple battery stacks 113 and increased component costs caused by newly providing a battery case 11 corresponding to the positional relationship between the cooling device 121 and the battery case 11. In order to solve these technical problems, the present embodiment proposes a structure in which the refrigerant branch part 112 can be detached from the case body 111.

[0025] Figure 3AAn example of a battery case 11 involved in an embodiment of the present utility model is shown. The refrigerant branch portion 112 is not formed integrally with the shell body 111. The refrigerant branch portion 112 is formed to be detachable relative to the shell body 111. In addition, the shape of the refrigerant branch portion 112 is designed to be able to cool the multiple battery stacks 113 as evenly as possible. That is, the shape of the refrigerant branch portion 112 is optimized according to the positional relationship between the cooling device 121 and the battery case 11. The shape of the surface of the refrigerant branch portion 112 that contacts the refrigerant 2 can be an arc or a rectangle.

[0026] In the present embodiment, since the refrigerant branching portion 112 having an optimal shape can be used, the plurality of battery stacks 113 can also be uniformly cooled. This contributes to an increase in the output and life of the battery.

[0027] Furthermore, the fact that the refrigerant branching portion 112 can be manufactured independently of the housing body 111 means that the housing body 111 of the same shape can be used in various situations regardless of the positional relationship between the cooling device 121 and the battery housing 11. Therefore, compared with the case where the refrigerant branching portion 112 is integrated with the housing body 111, it helps to reduce the cost of parts.

[0028] Figure 3B and Figure 3C An example of a joining method of the housing body 111 and the refrigerant branching portion 112 is shown.

[0029] Here, the shell body 111 and the refrigerant branch part 112 form a labyrinth structure by making the contact surface 1112B of the shell body 111 and the contact surface 1121B of the refrigerant branch part dock in a step-like manner. This labyrinth structure can prevent foreign matter such as sand or dust from invading the battery shell 11. In addition, the shell body 111 and the refrigerant branch part 112 are integrated by the bolts 3 that penetrate the refrigerant branch part 112. Here, with respect to the shell body 111 and the refrigerant branch part 112, the bolts may be exposed from the shell body 111, and the refrigerant branch part 112 provided with a through hole may be fastened with nuts.

[0030] As other embodiments of the shell body 111 and the refrigerant branching portion 112, Figure 3CAs shown, there is a structure that allows the refrigerant branch portion 112 to slide and fit relative to the shell body 111. For example, a groove portion 1112C is provided on the shell body 111. On the other hand, a convex portion 1121C having a shape corresponding to the groove portion 1112C of the shell body 111 is provided on the refrigerant branch portion 112. Therefore, the convex portion 1121C of the refrigerant branch portion 112 can be inserted into the groove portion 1112C of the shell body 111 to slide. As a result, the shell body 111 and the refrigerant branch portion 112 are joined to form a labyrinth structure. The labyrinth structure can prevent foreign matter such as sand or dust from invading the battery case 11.

Claims

1. A battery housing for accommodating a plurality of battery stacks, characterized in that: have: a housing body having a plurality of refrigerant passages configured to allow refrigerant to flow to each of the plurality of battery stacks; and a refrigerant branching portion configured to distribute the refrigerant to the plurality of refrigerant passages, The refrigerant branching portion is attachable to and detachable from the shell body.

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