Power battery pack and power battery

Abstract

The present invention discloses a power battery pack and power battery, comprising a frame, a battery module, and an explosion-proof valve. The battery module is located within the frame, a first pressure relief hole is provided on the end plate of the battery module, and a second pressure relief hole is provided on the frame. The pressure relief pipe of the explosion-proof valve is connected to the first pressure relief hole, and the valve body of the explosion-proof valve passes through the second pressure relief hole. This improves the effectiveness of thermal runaway protection for the battery cell.

Description

Technical Field

[0001] The present invention relates to the technical field of power battery thermal runaway protection, and in particular to a power battery pack and a power battery. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Current protection against thermal runaway in battery cells is primarily achieved by installing explosion-proof valves on the battery modules within the battery pack. These valves consist of a pressure relief pipe and a valve body, which is connected to the pressure relief pipe. A breathable membrane and fire-resistant components are located within the valve body. The membrane's opening is adjustable. When the battery cell is operating normally, the membrane opens slightly, connecting the battery interior and the external atmosphere through the membrane and pressure relief pipe to balance the pressure differential between the inside and outside of the battery pack. When thermal runaway occurs, the membrane opens to its maximum extent to quickly expel the high-temperature gases within the battery pack, effectively protecting the battery cell from thermal runaway.

[0004] The inventors believe that existing explosion-proof valves are typically mounted on the battery pack frame and lack direct connection to the module. This results in the need for high-temperature, high-pressure gases to diffuse within the battery pack before triggering the explosion-proof valve to release pressure when thermal runaway occurs within the battery module. This provides limited protection against thermal runaway, potentially missing the optimal time for decompression within the battery pack and endangering passenger compartment safety. Summary of the Invention

[0005] In order to solve the above problems, the present invention proposes a power battery pack and a power battery, in which the frame and the end plate of the battery module are connected through an explosion-proof valve to form a pressure relief channel. At the moment when thermal runaway occurs in the battery cell, the high-temperature and high-pressure gas directly diffuses from the battery module to the outside of the battery pack, without the need to fill the entire battery pack first, thereby improving the effectiveness of thermal runaway protection of the battery cell.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] In the first aspect, a power battery pack is proposed, including a frame, a battery module and an explosion-proof valve. The battery module is located in the frame, a first pressure relief hole is set on the end plate of the battery module, and a second pressure relief hole is set on the frame. The pressure relief pipe of the explosion-proof valve is connected to the first pressure relief hole, and the valve body of the explosion-proof valve passes through the second pressure relief hole.

[0008] In a second aspect, a power battery is proposed, including a power battery pack proposed in the first aspect.

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] 1. The battery pack proposed in the present invention connects the frame and the end plate of the battery module through an explosion-proof valve to form a pressure relief channel. At the moment of thermal runaway of the battery cell, high-temperature and high-pressure gas directly diffuses from the battery module to the outside of the battery pack without the need to fill the entire battery pack first, thereby improving the effectiveness of thermal runaway protection of the battery cell.

[0011] 2. The present invention provides a pressure relief channel for each battery module. When thermal runaway occurs in the battery cells of one battery module, the entire pressure relief process is only carried out in this battery module, which will not affect the functions and structural integrity of other battery modules, thereby improving the maintainability and economy of the battery pack to a certain extent.

[0012] Advantages of additional aspects of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The drawings in the specification, which constitute a part of this application, are used to provide further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute improper limitations on this application.

[0014] Figure 1 The exploded view of the battery pack disclosed in Example 1;

[0015] Figure 2 This is an assembly diagram of the explosion-proof valve disclosed in Example 1;

[0016] Figure 3 This is a schematic diagram of the sealing ring structure of the explosion-proof valve disclosed in Example 1;

[0017] Figure 4 This is a schematic diagram of the first pressure relief hole structure disclosed in Example 1.

[0018] Among them: 1. Upper shell, 2. Battery module, 3. Frame, 4. Bottom guard plate, 5. Explosion-proof valve, 6. Second pressure relief hole, 7. First pressure relief hole, 8. Sealing groove, 9. Sealing ring. DETAILED DESCRIPTION

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0021] Example 1

[0022] In this embodiment, a power battery pack is disclosed, such as Figure 1 、 Figure 2 As shown, it includes a frame 3, a battery module 2 and an explosion-proof valve 5. The battery module 2 is located in the frame 3. A first pressure relief hole 7 is set on the end plate of the battery module 2. The pressure relief pipe of the explosion-proof valve 5 is connected to the first pressure relief hole 7. The valve body of the explosion-proof valve 5 passes through the second pressure relief hole 6, and the frame 3 and the end plate of the battery module 2 are connected through the explosion-proof valve 5 to form a pressure relief channel. The gas in the battery module can be directly discharged from the battery pack through the pressure relief channel. When the battery cell in the battery module has thermal runaway, the high-temperature and high-pressure gas in the battery module is directly discharged from the module to the battery pack without filling the entire battery pack first and then releasing it to the outside of the pack. This shortens the pressure relief path, further improves the efficiency of blocking thermal runaway, and improves the effectiveness of thermal runaway protection of the battery cell.

[0023] The frame 3 includes a plurality of sub-frames, which are connected end to end to form the frame 3 , and the second pressure relief hole 6 passes through the sub-frames in which the second pressure relief hole is provided.

[0024] The first pressure relief hole 7 passes through the end plate of the battery module 2 .

[0025] The inner diameter of the second pressure relief hole 6 is adapted to the outer diameter of the valve body of the explosion-proof valve 5 , and the positions of the first pressure relief hole 7 and the second pressure relief hole 6 correspond to each other. The pressure relief pipe of the explosion-proof valve 5 can be connected to the first pressure relief hole 7 , and the valve body of the explosion-proof valve 5 passes through the second pressure relief hole 6 .

[0026] In order to ensure the airtightness of the battery module when thermal runaway occurs and pressure relief occurs in the battery cell, the pressure relief pipe of the explosion-proof valve 5 is sealed and connected to the first pressure relief hole 7 .

[0027] In order to ensure the sealing effect between the pressure relief pipe and the first pressure relief hole, improve the pressure relief efficiency, and thus improve the effectiveness of thermal runaway protection of the battery cell, the pressure relief pipe of the explosion-proof valve 5 is sealed and connected to the first pressure relief hole 7 through multiple sealing rings 9.

[0028] Take the example of using two sealing rings to seal the pressure relief pipe and the first pressure relief hole 7 as an example. Figure 3 、 Figure 4 As shown, two sealing grooves 8 are provided on the inner wall of the first pressure relief hole 7, two sealing rings are sleeved on the outside of the pressure relief pipe, the pressure relief pipe is extended into the first pressure relief hole 7, and the two sealing rings are respectively located in the sealing grooves 8, thereby realizing a sealed connection between the pressure relief pipe of the explosion-proof valve 5 and the first pressure relief hole 7.

[0029] In order to ensure the pressure relief effect of the battery module, one or more first pressure relief holes 7 can be set on the end plate of each battery module 2, and the same number of second pressure relief holes 6 as the first pressure relief holes 7 are set on the frame 3. Each first pressure relief hole is connected to an explosion-proof valve 5, and the valve body of each explosion-proof valve 5 passes through the corresponding second pressure relief hole 6, thereby realizing the setting of one or more pressure relief channels for the battery module. When thermal runaway occurs in the battery cell, the pressure of a battery module is simultaneously relieved through multiple pressure relief channels, thereby improving the efficiency of pressure relief and the effectiveness of thermal runaway protection of the battery cell.

[0030] In the battery pack disclosed in this embodiment, one or more battery modules 2 can be arranged in the frame 3, and a first pressure relief hole 7 is provided on the end plate of each battery module 2. Second pressure relief holes 6 with the same number as the first pressure relief holes 7 are provided on the frame 3. Each first pressure relief hole 7 is connected to an explosion-proof valve 5, and the valve body of each explosion-proof valve 5 passes through the corresponding second pressure relief hole 6, so that a pressure relief channel is provided for each battery module, and precise pressure relief of each battery module is achieved. When thermal runaway occurs in the battery cells in a single battery module, the high-temperature and high-pressure gas in the battery module is directly discharged from the battery pack, which will not affect the functions and structural integrity of other modules, thereby improving the maintainability and economy of the battery pack to a certain extent.

[0031] The battery pack disclosed in this embodiment further includes an upper shell 1 and a bottom guard plate 4 .

[0032] Specifically, an upper shell 1 is provided on one side of the frame 3 , and a bottom guard plate 4 is provided on the other side. The battery module 2 is located between the upper shell 1 and the bottom guard plate 4 , and the battery module 2 is protected by the bottom guard plate 4 and the upper shell 1 .

[0033] In addition, in order to accurately control the temperature of the battery cell, this embodiment also provides a liquid cooling plate between the upper shell and the lower shell. The battery module is located between the upper shell and the bottom guard plate. The battery module is cooled by the liquid cooling plate to prevent thermal runaway of the battery cell.

[0034] The frame body of this embodiment is extruded from a profile, and a corresponding second pressure relief hole is opened on the profile according to the size of the explosion-proof valve body to facilitate the assembly of the explosion-proof valve.

[0035] The end plates of the battery modules are cast.

[0036] The explosion-proof valve is detachably connected to the frame. Preferably, the valve body of the explosion-proof valve is connected to the frame with bolts to facilitate replacement of the explosion-proof valve.

[0037] The sub-frame is welded to form a frame, and the frame is welded to the liquid cooling plate.

[0038] The liquid cooling plate and the battery module are bonded with thermally conductive structural adhesive.

[0039] The battery pack disclosed in this embodiment connects the template of the battery module with the frame through an explosion-proof valve. When the battery cell in the module suffers thermal runaway, the high-temperature and high-pressure gas will pass through the pressure relief pipe of the explosion-proof valve, break through the breathable membrane in the valve body of the explosion-proof valve, and quickly release the pressure in the module, thereby achieving the purpose of thermal runaway protection and improving the effectiveness of thermal runaway protection of the battery cell.

[0040] Example 2

[0041] In this embodiment, a power battery is disclosed, including a power battery pack disclosed in Example 1.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A power battery pack, characterized in that: It includes a frame, a battery module and an explosion-proof valve. The battery module is located in the frame. A first pressure relief hole is set on the end plate of the battery module, and a second pressure relief hole is set on the frame. The pressure relief pipe of the explosion-proof valve is connected to the first pressure relief hole, and the valve body of the explosion-proof valve passes through the second pressure relief hole. One or more battery modules are set in the frame. A first pressure relief hole is set on the end plate of each battery module, and second pressure relief holes with the same number as the first pressure relief holes are set on the frame. Each first pressure relief hole is connected to an explosion-proof valve, and the valve body of each explosion-proof valve passes through the corresponding second pressure relief hole.

2. A power battery pack according to claim 1, characterized in that: The pressure relief pipe of the explosion-proof valve is sealedly connected to the first pressure relief hole.

3. A power battery pack according to claim 2, characterized in that: The pressure relief pipe of the explosion-proof valve is sealed and connected to the first pressure relief hole through a plurality of sealing rings.

4. A power battery pack according to claim 1, characterized in that: The first pressure relief hole and the second pressure relief hole are located correspondingly.

5. The power battery pack according to claim 1, characterized in that: The first pressure relief hole passes through the end plate, and the second pressure relief hole passes through the sub-frame on which the second pressure relief hole is arranged.

6. The power battery pack according to claim 1, characterized in that: One or more first pressure relief holes are provided on the end cover, and the same number of second pressure relief holes as the first pressure relief holes is provided on the frame. Each first pressure relief hole is connected to an explosion-proof valve, and the valve body of each explosion-proof valve passes through the corresponding second pressure relief hole.

7. The power battery pack according to claim 1, characterized in that: An upper shell is arranged on one side of the frame, and a bottom guard plate is arranged on the other side, and the battery module is located between the upper shell and the bottom guard plate.

8. A power battery pack according to claim 7, characterized in that: A liquid cooling plate is also provided between the upper shell and the lower shell, and the battery module is located between the upper shell and the bottom guard plate.

9. A power battery, characterized in that: A power battery pack comprising any one of claims 1 to 8.

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