Cover plate assembly, battery cell and battery

Abstract

The utility model relates to the technical field of battery manufacturing, in particular to a cover plate assembly which comprises a cover plate main body and a push rod, a pressure relief box is arranged on the cover plate main body, the pressure relief box is provided with a pressure relief cavity, an opening is formed in one end, deviating from the interior of the battery cell, of the pressure relief box, and a pressure relief hole is formed in the bottom of the pressure relief box in a penetrating manner and is communicated with an internal cavity of the battery cell. The push rod is movably arranged in the pressure relief cavity, the push rod has the trend of moving to the position separating the pressure relief hole and the opening, the push rod can be pushed by gas in the battery cell to move to the position communicating the pressure relief hole and the opening, the gas in the battery cell can overflow out of the battery cell from the pressure relief hole and the opening, the expansion degree of the battery cell is reduced, and the safety performance is improved. The utility model further provides a battery cell which comprises a box body and the cover plate assembly, and the cover plate assembly is arranged at the box opening of the box body. The utility model also provides a battery which comprises a shell and a plurality of battery cells, and the plurality of battery cells are arranged in the shell.

Description

Technical Field

[0001] The utility model relates to the technical field of battery manufacturing, in particular to a cover plate assembly, a battery core and a battery. Background Art

[0002] During the process of charging and discharging the battery, chemical reactions in the battery cell will produce gas, causing the battery cell to expand and increase the force between the battery cells. After repeated charging and discharging, the battery cell expansion will reduce the safety performance of the battery cell and shorten the life of the battery cell.

[0003] Therefore, there is an urgent need for a cover plate assembly, a battery cell and a battery to solve the above problems. Utility Model Content

[0004] One purpose of the utility model is to provide a cover plate assembly, which can improve the safety performance of the battery core and extend the service life.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] A cover plate assembly is provided, comprising:

[0007] A cover plate body, wherein a pressure relief box is arranged on the cover plate body, the pressure relief box has a pressure relief cavity, an end of the pressure relief box facing away from the interior of the battery cell has an opening, a bottom of the pressure relief box is penetrated by a pressure relief hole, and the pressure relief hole is connected to the internal chamber of the battery cell;

[0008] A push rod is movably arranged in the pressure relief chamber, and has a tendency to move to a position separating the pressure relief hole and the opening. The push rod can be moved to a position connecting the pressure relief hole and the opening under the push of gas inside the battery cell.

[0009] Optionally, a sealing ring is further included, wherein the sealing ring is clamped between the push rod and the box bottom, and the sealing ring is arranged around the pressure relief hole.

[0010] Optionally, an annular positioning groove is formed on the bottom of the box, and the sealing ring is partially located in the annular positioning groove.

[0011] Optionally, it further includes a valve sleeve, which is arranged in the pressure relief chamber, the valve sleeve is connected to the pressure relief box, the valve sleeve is provided with a receiving groove, the receiving groove is opened toward the internal chamber, and the push rod is movably inserted in the receiving groove.

[0012] Optionally, a guide groove is formed on the side wall of the accommodating groove, and a guide protrusion is correspondingly provided on the push rod, and the guide protrusion is inserted into the guide groove so that the guide protrusion can move relative to the valve sleeve along the axial direction of the push rod.

[0013] Optionally, an end surface of the valve sleeve facing away from the internal chamber is located at the opening, and an exhaust groove is provided on the end surface, and the exhaust groove is used to connect the pressure relief chamber with the opening.

[0014] Optionally, an elastic member is further included, one end of the elastic member is connected to the valve sleeve, and the other end is connected to the push rod, and the elastic member is used to make the push rod have a tendency to move to a position that separates the pressure relief hole and the opening.

[0015] Optionally, the pressure relief hole can also be used to inject electrolyte.

[0016] Another object of the utility model is to provide a battery cell that can improve the safety performance of the battery cell and extend its service life.

[0017] To achieve this purpose, the utility model adopts the following technical solutions:

[0018] Provided is a battery cell, comprising a box body and the above-mentioned cover plate assembly, wherein the cover plate assembly is arranged at the box opening of the box body.

[0019] Another object of the present invention is to provide a battery that can improve the safety performance of the battery cell and extend the service life.

[0020] To achieve this purpose, the utility model adopts the following technical solutions:

[0021] A battery is provided, comprising a shell and a plurality of the above-mentioned battery cells, wherein the plurality of the battery cells are arranged in the shell.

[0022] Beneficial effects of the utility model:

[0023] The utility model provides a cover plate assembly, including a cover plate body and a push rod. A pressure relief box is provided on the cover plate body, the pressure relief box has a pressure relief cavity, one end of the pressure relief box facing away from the interior of the battery cell has an opening, and a pressure relief hole is provided through the bottom of the pressure relief box, and the pressure relief hole is connected to the internal chamber of the battery cell. The push rod is movably arranged in the pressure relief cavity, and the push rod has a tendency to move to a position that separates the pressure relief hole and the opening, at which time the push rod separates the internal chamber of the battery cell from the outside of the battery cell. The push rod can move to a position that connects the pressure relief hole and the opening under the push of the gas inside the battery cell, that is, when the air pressure inside the battery cell gradually increases, the push rod will move to a position that connects the pressure relief hole and the opening, that is, the gas in the battery cell will overflow from the pressure relief hole and the opening to the outside of the battery cell, thereby reducing the expansion degree of the battery cell, improving the safety performance of the battery cell, and extending the service life.

[0024] The utility model also provides a battery core, comprising a box body and the above-mentioned cover plate assembly, wherein the cover plate assembly is arranged at the box opening of the box body. The battery core can improve its own safety performance and extend its service life.

[0025] The utility model also provides a battery, comprising a housing and a plurality of the above-mentioned battery cells, wherein the plurality of battery cells are arranged in the housing. The battery cells of the battery have higher safety performance and can extend service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a structural schematic diagram of a cover plate assembly provided by an embodiment of the utility model from a first perspective;

[0027] Figure 2 is an exploded view of the cover plate assembly provided in an embodiment of the utility model;

[0028] Figure 3 is a structural schematic diagram of a cover plate assembly provided by an embodiment of the utility model from a second viewing angle;

[0029] Figure 4 yes Figure 3 AA section view.

[0030] In the figure:

[0031] 1. Cover plate body; 11. Pressure relief box; 111. Pressure relief cavity; 112. Opening; 113. Pressure relief hole; 114. Spinning edge;

[0032] 2. Push rod; 21. Guide protrusion; 3. Sealing ring; 4. Valve sleeve; 41. Guide groove; 42. Exhaust groove; 5. Elastic member. DETAILED DESCRIPTION

[0033] The technical solution of the utility model is further described below in conjunction with the accompanying drawings and implementation methods. It is understood that the specific embodiments described herein are only used to explain the utility model, rather than to limit the utility model. It should also be noted that, for the convenience of description, only the parts related to the utility model are shown in the accompanying drawings, rather than all.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0036] like Figure 1-Figure 4 As shown, the cover assembly of this embodiment includes a cover body 1 and a push rod 2. Among them, a pressure relief box 11 is provided on the cover body 1, and the pressure relief box 11 has a pressure relief cavity 111. The end of the pressure relief box 11 away from the inside of the battery cell has an opening 112. The bottom of the pressure relief box 11 is penetrated by a pressure relief hole 113, and the pressure relief hole 113 is connected to the internal chamber of the battery cell. The push rod 2 is movably arranged in the pressure relief cavity 111, and the push rod 2 has a tendency to move to a position that separates the pressure relief hole 113 and the opening 112. At this time, the push rod 2 separates the internal chamber of the battery cell from the outside of the battery cell to ensure the sealing of the battery cell. The push rod 2 can move to a position connecting the pressure relief hole 113 and the opening 112 under the push of the gas inside the battery cell. That is, when the air pressure inside the battery cell gradually increases, the push rod 2 will move to a position connecting the pressure relief hole 113 and the opening 112. That is, the gas in the battery cell will overflow from the pressure relief hole 113 and the opening 112 to the outside of the battery cell, thereby reducing the expansion degree of the battery cell, improving the safety performance of the battery cell, and extending the service life.

[0037] In order to improve the sealing performance, the cover plate assembly may further include a sealing ring 3, which is sandwiched between the push rod 2 and the bottom of the box and is arranged around the pressure relief hole 113. One end surface of the push rod 2 abuts against the sealing ring 3, and in this embodiment, the push rod 2, the sealing ring 3 and the pressure relief box 11 are coaxially arranged.

[0038] Optionally, an annular positioning groove is provided at the bottom of the box, and the sealing ring 3 is partially located in the annular positioning groove. Optionally, the cross section of the sealing ring 3 is T-shaped, that is, the sealing ring 3 includes a first ring parallel to the cover body 1 and a second ring perpendicular to the cover body 1, the second ring is inserted in the annular positioning groove, and the first ring abuts against the end face of the push rod 2 to form a surface seal.

[0039] Optionally, the cover plate assembly also includes a valve sleeve 4, which is arranged in the pressure relief chamber 111, and the valve sleeve 4 is connected to the pressure relief box 11. The valve sleeve 4 is provided with a receiving groove, and the receiving groove is opened toward the internal chamber. The push rod 2 is movably inserted in the receiving groove to limit the moving direction of the push rod 2, thereby ensuring the stability of the pressure relief performance of the cover plate assembly.

[0040] Optionally, a guide groove 41 is formed on the side wall of the accommodating groove, and a guide protrusion 21 is correspondingly provided on the push rod 2. The guide protrusion 21 is inserted into the guide groove 41 so that the guide protrusion 21 can move relative to the valve sleeve 4 along the axial direction of the push rod 2, so as to further limit the moving direction of the push rod 2, prevent the push rod 2 from rotating along its own axial direction, and ensure the stability of the pressure relief.

[0041] Optionally, the end surface of the valve sleeve 4 facing away from the internal chamber is located at the opening 112 , and an exhaust groove 42 is formed on the end surface. The exhaust groove 42 is used to connect the pressure relief chamber 111 with the opening 112 .

[0042] Optionally, the opening 112 of the pressure relief box 11 is bent inward to cover the end surface of the valve sleeve 4 to form a spinning edge 114. The spinning edge 114 is formed by one-time spinning by a spinning device, and the pressure head of the spinning device revolves around the opening 112 and rotates at the same time to achieve spinning fixation.

[0043] Optionally, a plurality of exhaust grooves 42 are provided on the end surface of the valve sleeve 4, and the plurality of exhaust grooves 42 are evenly spaced and arranged around the center of the opening 112 to ensure balanced pressure relief and prevent excessive local force. Optionally, each exhaust groove 42 is partially located on the end surface, and partially located on the edge and passes through the end surface.

[0044] Optionally, the cover plate assembly further comprises an elastic member 5, one end of which is connected to the valve sleeve 4, and the other end is connected to the push rod 2, and the elastic member 5 is used to make the push rod 2 have a tendency to move to a position that separates the pressure relief hole 113 and the opening 112. Optionally, the elastic member 5 is a spring, which is sleeved on the main body of the push rod 2, one end of which is connected to the bottom of the accommodating groove of the valve sleeve 4, and the other end is connected to the pushing end face of the push rod 2, so that there is a certain abutment force between the push rod 2 and the sealing ring 3. The magnitude of the abutment force is related to the critical value of the pressure relief of the battery cell, that is, a spring with a suitable elastic force is selected according to the critical value of the pressure relief of the battery cell.

[0045] Optionally, the pressure relief hole 113 can also be used to inject electrolyte, that is, the pressure relief hole 113 is also a liquid injection hole, that is, after liquid injection, the sealing ring 3, the push rod 2, the spring, the valve sleeve 4 and other pressure relief components are installed to prevent the electrolyte from overflowing and contaminating the pressure relief components during liquid injection.

[0046] Optionally, in this embodiment, the cover body 1 is rectangular. Of course, in other embodiments, the shape of the cover body 1 can also be adjusted according to the shape of the battery cell.

[0047] When the gas generated during the charge and discharge process of the battery cell gathers to a certain critical value, the push rod 2 is pushed upward by the gas, the sealing amount of the sealing ring 3 under the push rod 2 becomes smaller, the contact surface pressure between the sealing ring 3 and the sealed part is insufficient, and it cannot be effectively sealed, and the gas can leak into the pressure relief cavity 111 of the pressure relief box 11, and then be discharged to the outside of the battery cell through the exhaust groove 42 on the valve sleeve 4. The cover plate assembly can effectively stabilize the internal gas pressure of the battery cell, enhance the safety of the battery cell, and extend the battery life.

[0048] This embodiment also provides a battery cell, comprising a box body and the above-mentioned cover plate assembly, wherein the cover plate assembly is arranged at the box opening of the box body. The battery cell can improve its own safety performance and extend its service life.

[0049] This embodiment also provides a battery, comprising a housing and a plurality of the above-mentioned battery cells, wherein the plurality of battery cells are arranged in the housing. The battery cells of the battery have higher safety performance and can extend service life.

[0050] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A cover plate assembly, characterized in that: include: A cover plate body (1), wherein a pressure relief box (11) is arranged on the cover plate body (1), the pressure relief box (11) has a pressure relief cavity (111), an end of the pressure relief box (11) facing away from the interior of the battery cell has an opening (112), a bottom of the pressure relief box (11) is penetrated by a pressure relief hole (113), and the pressure relief hole (113) is connected to the internal cavity of the battery cell; A push rod (2), wherein the push rod (2) is movably arranged in the pressure relief chamber (111), and the push rod (2) has a tendency to move to a position separating the pressure relief hole (113) and the opening (112), and the push rod (2) can be moved to a position connecting the pressure relief hole (113) and the opening (112) under the push of gas inside the battery cell.

2. The cover plate assembly according to claim 1, characterized in that: It also comprises a sealing ring (3), wherein the sealing ring (3) is sandwiched between the push rod (2) and the box bottom, and the sealing ring (3) is arranged around the pressure relief hole (113).

3. The cover plate assembly according to claim 2, characterized in that: The box bottom is provided with an annular positioning groove, and the sealing ring (3) is partially located in the annular positioning groove.

4. The cover plate assembly according to claim 1, characterized in that: It also includes a valve sleeve (4), which is arranged in the pressure relief chamber (111), the valve sleeve (4) is connected to the pressure relief box (11), and the valve sleeve (4) is provided with a receiving groove, which is opened toward the internal chamber, and the push rod (2) is movably inserted in the receiving groove.

5. The cover plate assembly according to claim 4, characterized in that: A guide groove (41) is provided on the side wall of the accommodating groove, and a guide protrusion (21) is correspondingly provided on the push rod (2). The guide protrusion (21) is inserted into the guide groove (41) so that the guide protrusion (21) can move relative to the valve sleeve (4) along the axial direction of the push rod (2).

6. The cover plate assembly according to claim 4, characterized in that: The end surface of the valve sleeve (4) facing away from the internal chamber is located at the opening (112), and the end surface is provided with an exhaust groove (42), and the exhaust groove (42) is used to connect the pressure relief chamber (111) and the opening (112).

7. The cover plate assembly according to claim 4, characterized in that: It also includes an elastic member (5), one end of which is connected to the valve sleeve (4), and the other end of which is connected to the push rod (2), and the elastic member (5) is used to make the push rod (2) have a tendency to move to a position that separates the pressure relief hole (113) and the opening (112).

8. The cover plate assembly according to any one of claims 1 to 7, characterized in that: The pressure relief hole (113) can also be used to inject electrolyte.

9. A battery cell, characterized in that: It comprises a box body and a cover plate assembly as described in any one of claims 1 to 8, wherein the cover plate assembly is arranged at the box opening of the box body.

10. A battery, characterized in that The invention comprises a shell and a plurality of battery cells as claimed in claim 9, wherein the plurality of battery cells are arranged in the shell.

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