Pressure relief assembly for battery pack and battery pack

Abstract

The utility model relates to the technical field of power batteries, in particular to a pressure relief assembly for a battery pack and the battery pack, the pressure relief assembly is mounted at a first exhaust port of the battery pack, and the pressure relief assembly comprises a spring piece and a valve body; the first end of the spring piece is clamped in a box body of the battery pack, the second end of the spring piece is clamped in the valve body, and the valve body seals the first exhaust port; and when the second end of the spring piece is separated from the valve body, the first exhaust port is opened. Therefore, the pressure relief assembly with the spring piece and the valve body in detachable connection is provided, in the pressure relief state, the spring piece is separated from the valve body and cannot automatically restore, and the problem that the pressure relief opening is closed again due to automatic restoration of an existing anti-explosion valve can be solved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and particularly provides a pressure relief component for a battery pack and a battery pack. Background Art

[0002] At present, with the rapid development of the new energy industry, new energy devices such as electric vehicles and electric aircraft have been widely used, and the battery pack, as the core part of the new energy device, has also been widely concerned.

[0003] To ensure the safety and stability of the battery pack, it is necessary to achieve waterproof and dustproof, that is, theoretically, it is necessary to achieve a sealed state. However, in the sealed state, once the battery cells of the power battery have a thermal runaway event, a large amount of gas will be generated, causing the gas pressure inside the box to rise rapidly. If the gas cannot be exhausted and the pressure relieved in time, it may lead to violent fire or even explosion.

[0004] In the prior art, there is a spring-type explosion-proof valve (which can also be called a pressure relief valve), which may retract under the action of the spring force after being opened, resulting in the pressure relief port being closed again.

[0005] To solve the above problems, the present application provides a new pressure relief component to overcome the above problems. Summary of the Utility Model

[0006] The utility model aims to solve the problem that the existing spring-type explosion-proof valve may retract under the action of the spring force after being opened.

[0007] In a first aspect, the utility model provides a pressure relief component for a battery pack. The pressure relief component is installed at a first exhaust port of the battery pack. The pressure relief component includes a spring piece and a valve body. The first end of the spring piece is clamped on the box body of the battery pack, and the second end of the spring piece is clamped on the valve body. The valve body closes the first exhaust port. Wherein, when the second end of the spring piece is separated from the valve body, the first exhaust port is opened.

[0008] Optionally, the pressure relief component further includes a sealing ring. The sealing ring is provided around the edge of the valve body close to the first exhaust port.

[0009] Optionally, the box body includes a side wall and profiles. The side wall and the plurality of profiles form an exhaust passage. The first exhaust port is arranged at the end of the exhaust passage. The side wall is provided with a second exhaust port, and the first exhaust port and the second exhaust port are communicated.

[0010] Optionally, the valve body is rectangular, and the four sides of the rectangle are respectively abutted against the side wall and each profile.

[0011] Optionally, the first side of the valve body in contact with the side wall is close to the second exhaust port, and a chamfered sliding port is provided at the edge of the second exhaust port.

[0012] Optionally, a dust-proof film covers the second exhaust port.

[0013] Optionally, the valve body is clamped on the limiting component of the battery pack.

[0014] Optionally, the limiting component includes a first limiting block and a second limiting block, and the second side of the valve body is clamped between the first limiting block and the second limiting block.

[0015] Optionally, the second end of the spring piece includes a hollow structure.

[0016] Optionally, the valve body further includes a limiting structure, and the second end of the spring piece is clamped in the limiting structure.

[0017] Optionally, the limiting structure includes a sliding area, and the second end of the spring piece slides along the sliding area so that the second end of the spring piece disengages from the valve body.

[0018] Optionally, the sliding area includes a slope.

[0019] In a second aspect, the present utility model further provides a battery pack, which includes a box body, a battery cell group, and a pressure relief component as described in any one of the above, the box body includes a side wall, and the battery cell group is arranged inside the box body.

[0020] In a third aspect, the present utility model further provides a new energy device, which includes the battery pack as above

[0021] Compared with the prior art, the present utility model has obvious advantages and beneficial effects. By means of the above technical solutions, the pressure relief component and the battery pack provided by the present utility model can achieve quite high technical progressiveness and practicality, and have wide utilization value in the industry. It has at least the following advantages:

[0022] In the case of adopting the above technical solutions, the present utility model provides a new pressure relief component. The spring piece and the valve body in the pressure relief component are a pressure relief component with a detachable connection. In the pressure relief state, the spring piece disengages from the valve body and cannot be automatically restored, which can solve the problem that the existing explosion-proof valve causes the pressure relief port to close again due to automatic restoration.

[0023] Furthermore, the present utility model provides a pressure relief component inside the battery pack box body, which brings the advantages of higher integration degree and shorter path for the thermal runaway pressure relief design. There is no need to additionally install an explosion-proof valve outside the battery pack. Description of the Drawings

[0024] The preferred embodiments of the present utility model will be described below in conjunction with the accompanying drawings, in which:

[0025] Figure 1 is a top view of a pressure relief component and a partial structure of a battery pack provided by the present utility model;

[0026] Figure 2 is a side view of a pressure relief component and a limiting component provided by the present utility model;

[0027] Figure 3 is an exploded view of a pressure relief component and a limiting component provided by the present utility model;

[0028] Figure 4 is an exploded view of a pressure relief component and a partial structure of a battery pack provided by the present utility model;

[0029] Figure 5 is a plan view of the inner profile of a battery pack box body provided by the present utility model;

[0030] Figure 6 is a partial schematic diagram of a battery pack box body provided by the present utility model;

[0031] Figure 7 is a detailed view of the second end of a spring piece provided by the present utility model;

[0032] Figure 8 is a schematic diagram of the side wall of a battery pack box body provided by the present utility model;

[0033] Figure 9 is Figure 8 an enlarged view of the area within the dashed box in;

[0034] Figure 10 is a schematic diagram of another perspective of a pressure relief component and a partial structure of a battery pack provided by the present utility model;

[0035] Figure 11 is Figure 10 an enlarged view of the area of the dashed box K in;

[0036] Figure 12 is a top view of another perspective of a pressure relief component and a partial structure of a battery pack provided by the present utility model;

[0037] Figure 13 is Figure 12 an enlarged view of the area within the dashed box in;

[0038] Figure 14 is a top view of a battery pack provided by the present utility model.

[0039] List of reference numerals:

[0040] 10. Pressure relief component; 101. Spring piece; 1011. First end of the spring piece; 1012. Second end of the spring piece; 10121. Hollow structure; 102. Valve body; 1021. Limiting structure; 10211. Sliding area; 103. Sealing ring; 20. First exhaust port; 30. Exhaust passage; 40. Side wall; 50. Second exhaust port; 501. Chamfered sliding port; 60. Profile; 601. Vent hole; 70. Dust-proof film; 80. Limiting component; 801. First limiting block; 802. Second limiting block; 803. Third limiting block; 90. Box body; X. Valve body rotation direction; Y. Spring detachment direction; M. Air pressure direction. Detailed implementation mode

[0041] As described in the background art, there is a problem that the existing spring-type explosion-proof valve may retract under the action of spring force after opening. Specifically, there are generally two forms of existing explosion-proof valves, spring type and thimble type. These two types usually protrude beyond the outer surface of the battery pack after installation, occupying more space. In addition, the spring-type explosion-proof valve may retract under the action of spring force after opening, resulting in the re-closure of the pressure relief port. The thimble-type valve will not return to its original state after opening, but generally has a larger opening pressure.

[0042] To solve the problems of the existing explosion-proof valves, the present application provides a new pressure relief component.

[0043] The following refers to the attached Figures 1 to 14 to describe the preferred implementation modes of the present invention. Those skilled in the art should understand that these implementation modes are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0044] It should be noted that in the description of the present invention, the terms "inner", "outer", "upper", "lower", "top", "bottom" and other terms indicating directions or position relationships are based on the directions or position relationships shown in the drawings. This is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0045] In addition, it should also be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "set", "connected", "installed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0046] In the first aspect, please refer to Figures 1 to 14, the present utility model provides a pressure relief component 10 for a battery pack. The pressure relief component 10 is installed at the first exhaust port 20 of the battery pack. The pressure relief component 10 includes a spring piece 101 and a valve body 102. Among them, the valve body 102 can be of any shape, such as circular, hexagonal, rectangular, etc. The valve body 102 can be designed as a gate shape, and the spring piece 101 controls the opening and closing of the gate-shaped valve body. In this application, the embodiment is described by taking a rectangle as an example.

[0047] The pressure relief component 10 includes a sealed state and a pressure relief state. When the air pressure in the battery pack is normal, the pressure relief component 10 is in the sealed state; when the air pressure in the battery pack is too high, the pressure relief component 10 is converted into the pressure relief state, and the gas in the battery pack can be discharged to the outside of the battery pack through the pressure relief component 10.

[0048] When the pressure relief component 10 is in the sealed state, the first end 1011 of the spring piece 101 is clamped on the box body 90 of the battery pack, and the second end 1012 of the spring piece 101 is clamped on the valve body 102. The valve body 102 is covered on the first exhaust port through the spring piece 101, and the first exhaust port 20 is closed, and the gas in the battery pack cannot be discharged through the pressure relief component.

[0049] When the pressure relief component 10 is in the pressure relief state, the second end 1012 of the spring piece 101 is detached from the valve body 102. The valve body 102 is no longer restricted by the elastic force of the spring piece 101, and the valve body 102 no longer closes the first exhaust port 20, and the first exhaust port 20 is opened.

[0050] In this embodiment, a pressure relief component with a detachable connection between the spring piece 101 and the valve body 102 is provided. In the pressure relief state, the spring piece 101 is detached from the valve body and cannot automatically recover, which can solve the problem that the existing explosion-proof valve causes the pressure relief port to close again due to automatic recovery.

[0051] Among them, the air pressure at which the battery pack enters the pressure relief state is related to the selection of the spring piece 101.

[0052] In a specific embodiment of a pressure relief component 10, please refer to Figure 3 , the pressure relief component 10 may further include a sealing ring 103; in the sealed state, the sealing ring 103 is disposed around the edge of the valve body 102 close to the first exhaust port 20. The sealing ring 103 can ensure that the valve body 102 can effectively close the first exhaust port 20 in the sealed state. Among them, the sealing ring 103 can be made of silicone, plastic or other materials with a sealing effect.

[0053] In a second aspect, the present utility model further provides a battery pack, which includes a box body, a battery cell group and a pressure relief component 10. The box body includes side walls, and the battery cell group is disposed inside the box body.

[0054] Specifically, the box body may include a box cover, a lower box body, and a bottom plate. The lower box body includes a plurality of side walls connected end to end. The box cover and the bottom plate are respectively disposed on two sides of the lower box body. Thus, a sealed battery cell cavity is formed inside the box body, and the battery cell group is disposed in the battery cell cavity.

[0055] It should be noted that the battery cells mentioned in the present utility model include, but are not limited to, one or more of cylindrical battery cells, square shell battery cells, and soft-pack battery cells. A plurality of battery cells are arranged to form a battery cell group.

[0056] In one embodiment, please refer to Figure 1 and Figure 4 , the box body of the battery pack is provided with an exhaust passage 30. The exhaust passage 30 can be disposed on the side or the bottom of the battery pack. If the exhaust passage 30 is disposed on the side of the battery pack, it can be constituted by the side wall 40 and the side profile connected to the side wall 40; if the exhaust passage 30 is disposed on the bottom of the battery pack, it can be constituted by the bottom plate and the bottom profile connected to the bottom plate. Whether the exhaust passage 30 is disposed on the side or the bottom of the battery pack, the sealing performance of the exhaust passage 30 needs to be ensured so that the gas can flow through the exhaust passage 30 to the pressure relief component 10. Refer to Figure 1 , the air pressure direction in the exhaust passage 30 is M.

[0057] In order to allow the gas in the battery pack to enter the exhaust passage,

[0058] In the subsequent embodiments, the present application takes the exhaust passage 30 disposed on the side of the battery pack as an example for description.

[0059] In order to allow the gas in the battery pack to enter the exhaust passage, a plurality of ventilation holes 601 can be provided on the side profile 601. Here, the ventilation area of the ventilation holes 601 can be determined according to the amount of gas generated by the battery cells and the gas generation rate during thermal runaway.

[0060] In one embodiment, the first exhaust port 20 is disposed at the end of the exhaust passage 30 of the battery pack, and the battery pack side wall 40 is provided with a second exhaust port 50. The first exhaust port 20 and the second exhaust port 50 are communicated.

[0061] The second exhaust port 50 is provided on the outer surface of the battery pack, and the first exhaust port 40 is provided inside the battery pack housing. The first exhaust port 20 is in communication with the second exhaust port 50, and gas can flow from the first exhaust port 20 to the second exhaust port 50, and then be discharged to the outside of the battery pack. The pressure relief component 10 is installed at the first exhaust port 20 inside the battery pack housing, which can prevent the pressure relief component 10 from protruding to the outside of the outer surface of the battery pack during assembly, so that the pressure relief component 10 does not affect the installation of other components outside the battery pack. Optionally, the second exhaust port 50 is covered with a dust-proof film 70 (which can also be called a "protective film") to prevent external dust, debris, etc. from entering the battery pack. Among them, the dust-proof film 70 can be attached to the outside of the battery pack.

[0062] In the above embodiment, the present invention provides a pressure relief component inside the battery pack housing, which brings the advantages of higher integration and shorter path for the thermal runaway pressure relief design. It enables the battery pack to not require an additional explosion-proof valve to be installed outside.

[0063] In some scenarios of automatic battery pack replacement (commonly known as "battery swapping"), the battery swapping device needs to detect the plane of the side wall of the battery pack to achieve the positioning of the battery pack. If an explosion-proof valve (i.e., the pressure relief component) protruding outside the battery pack is provided on the side wall, it may affect the accuracy of positioning. Installing the pressure relief component inside the battery pack can avoid this problem.

[0064] In one embodiment, the valve body 102 is rectangular, and the four sides of the rectangle are respectively in contact with the side wall 40 and each face profile 60. Please refer to Figures 1 to 14 , one side of the valve body 102 close to the side wall 40 is in contact with the side wall, and the other three sides of the valve body 102 are in contact with three face profiles. Thus, in the sealed state, the rectangular gate valve 102 covers the end (i.e., the first exhaust port 20) of the exhaust passage 30 with a rectangular cross-section.

[0065] In one embodiment, please refer to Figure 1 、 Figure 8 、 Figure 9 、 Figure 12 and Figure 13 , the side of the valve body 102 in contact with the side wall 40 (denoted as the first side, not shown in the figure) is close to the second exhaust port 50, and one edge of the second exhaust port 50 is chamfered to form a chamfered sliding port 501.

[0066] Thus, when the second end 1012 of the spring piece 101 detaches from the valve body 102, the second end 1012 of the spring piece 101 slides out of the chamfered sliding port 501 along the Y direction to the outside of the second exhaust port 50, that is, to the outside of the battery pack. Thus, the side of the valve body 102 that abuts against the side wall 40 is no longer limited by the spring piece 101, and the valve body 102 rotates along the X direction, and the first exhaust port 20 opens. The chamfered sliding port 501 can shorten the sliding distance when the second end 1012 of the spring piece 101 detaches from the valve body 102, making it easier for the spring piece 101 to detach, and avoiding the problem that the spring of the pressure relief component 10 gets stuck and cannot relieve pressure smoothly when the air pressure in the battery pack is too high.

[0067] In one embodiment, the valve body 102 is clamped on the limiting component 80 of the battery pack.

[0068] In a specific embodiment of the limiting component 80, the limiting component 80 includes a first limiting block 801 and a second limiting block 802. In the sealed state, the second side of the valve body 102 is clamped between the first limiting block 801 and the second limiting block 802.

[0069] In a specific embodiment of the limiting component 80, the limiting component 80 includes a first limiting block 801, a second limiting block 802, and a third limiting block 803. In the sealed state, the second side of the valve body 102 is clamped between the first limiting block 801 and the second limiting block 802, one side of the first side of the valve body 102 is limited by the third limiting block 803, and the other side of the first side is abutted by the second end 1012 of the spring piece 101.

[0070] Optionally, the limiting blocks (including the first limiting block 801, the second limiting block 802, and the third limiting block 803) can each be one or more, and the limiting blocks can be set in different shapes, such as a cuboid, a tetrahedron, etc., as long as they can effectively clamp the valve body 102.

[0071] In a specific example, as shown in the figure, there are 2 second limiting blocks 802 and 2 third limiting blocks 803, both of which are tetrahedrons. The second limiting block 802 is arranged on the inner wall of the side wall 40, and the third limiting block 803 is arranged on the profile 60. There are also 2 first limiting blocks 801, which are cuboids. After abutting one side of the valve body 102 against the second limiting block 802 and the third limiting block 803, the first limiting block 801 is installed on the inner wall of the side wall 40 by gluing or spot welding.

[0072] It should be noted that the limiting component 80 includes, but is not limited to, the form of limiting blocks, and other limiting structures can also be used. For example, the limiting component 80 is a card slot, and a clamping member corresponding to the card slot is provided on the valve body 102, and the clamping member is clamped in the card slot to realize the limitation of the valve body 102.

[0073] In one embodiment, refer to Figure 7 and Figure 10 and Figure 11 , the second end 1012 of the spring piece 101 includes a hollow structure 10121. One end of the spring piece 101 in contact with the valve body 102 (i.e., the second end 1012) forms a plane, and this plane is clamped on the valve body 102 to achieve the connection and fixation between the two. When the air pressure in the battery pack rises, when the plane of the second end 1012 of the spring piece 101 detaches from the valve body 102, a frictional force is generated between the two. If the frictional force is too large, it may cause the pressure relief component 10 to fail to relieve the pressure of the battery pack in time, resulting in more serious thermal runaway consequences. To avoid this problem, a hollow structure 10121 can be provided on the plane of the second end 1012 of the spring piece 101 to reduce the frictional force between the second end 1012 and the valve body 102, making it easier for the spring piece 101 to detach from the valve body 102.

[0074] Optionally, the hollow structure 10121 can be a hollowed-out area on the plane of the second end 1012, including but not limited to the shapes shown in the figure.

[0075] In one embodiment, refer to Figure 1 and Figure 3 and Figure 10 and Figure 11 , the valve body 102 further includes a limiting structure 1021; in the sealed state, the second end 1012 of the spring piece 101 is clamped in the limiting structure 1021.

[0076] To effectively limit the second end 1012 of the spring piece 101, a limiting structure 1021 is provided on the valve body 102. Optionally, the plane of the second end 1012 is clamped in the limiting structure 1021.

[0077] In one embodiment, the limiting structure 1021 includes a sliding area 10211, and the second end 1012 of the spring piece (specifically referring to the plane of the second end 1012) slides along the sliding area 10211, so that the second end 1012 of the spring piece 101 detaches from the valve body 102.

[0078] Optionally, the sliding area 10211 includes a slope (not shown in the figure). Further, the second end 1012 of the spring piece 101 slides out of the sliding area 10211 along the slope from high to low. In the pressure relief state, it can make the second end 1012 of the spring piece 101 easier to detach from the valve body 102, avoiding the risk of thermal runaway caused by the failure to relieve the pressure in time.

[0079] In one embodiment, refer to Figure 14, the pressure relief component 10 can be arranged at the corners of the battery pack. Specifically, a profile 60 is connected inside the side wall of the battery pack to form an exhaust passage, and the pressure relief component 10 is arranged at the end of the profile 60.

[0080] In a third aspect, the present utility model further provides a new energy device. The new energy device of the present utility model may include the above-mentioned battery pack, and the new energy device may refer to devices such as electric vehicles and electric aircraft.

[0081] Those skilled in the art can understand that although some embodiments herein include certain features included in other embodiments rather than other features, the combination of features of different embodiments means that it is within the scope of the present application and forms different embodiments. For example, in the claims of the present application, any one of the claimed embodiments can be used in any combination.

[0082] So far, the technical solutions of the present utility model have been described in conjunction with the preferred embodiments shown in the drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present utility model is obviously not limited to these specific embodiments. Without departing from the principle of the present utility model, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present utility model.

Claims

1. A pressure relief component for a battery pack, characterized in that The pressure relief component is installed at the first exhaust port of the battery pack, and the pressure relief component includes a spring piece and a valve body; The first end of the spring piece is clamped on the box body of the battery pack, the second end of the spring piece is clamped on the valve body, and the valve body closes the first exhaust port; Wherein, when the second end of the spring piece is separated from the valve body, the first exhaust port is opened.

2. The pressure relief component according to claim 1, wherein The pressure relief component further includes a sealing ring; The sealing ring is disposed around the edge of the valve body close to the first exhaust port.

3. The pressure relief component according to claim 1, wherein The box body includes a side wall and profiles, the side wall and the plurality of profiles form an exhaust passage, the first exhaust port is disposed at an end of the exhaust passage, the side wall is provided with a second exhaust port, and the first exhaust port is communicated with the second exhaust port.

4. The pressure relief component according to claim 3, wherein The valve body is rectangular, and the four sides of the rectangle are respectively in contact with the side wall and each profile.

5. The pressure relief component according to claim 4, wherein The first side of the valve body in contact with the side wall is close to the second exhaust port, and the edge of the second exhaust port is provided with a chamfered sliding port.

6. The pressure relief component according to any one of claims 3 to 5, characterized in that, The second exhaust port is covered with a dust-proof film.

7. The pressure relief component according to claim 1, characterized in that, The valve body is clamped on the limiting component of the battery pack.

8. The pressure relief component according to claim 7, characterized in that The limiting component includes a first limiting block and a second limiting block, and the second side of the valve body is clamped between the first limiting block and the second limiting block.

9. The pressure relief component according to claim 1, wherein The second end of the spring piece includes a hollow structure.

10. The pressure relief component according to claim 1, characterized in that, The valve body further includes a limiting structure, and the second end of the spring piece is clamped in the limiting structure.

11. The pressure relief component according to claim 10, wherein, The limiting structure includes a sliding area, and the second end of the spring piece slides along the sliding area, so that the second end of the spring piece is separated from the valve body.

12. The pressure relief component according to claim 11, wherein The sliding area includes a slope.

13. A battery pack, characterized in that, The battery pack includes a box body, a battery cell group and the pressure relief component according to any one of claims 1 to 12, the box body includes a side wall, and the battery cell group is disposed in the box body.

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