Shell for power battery and power battery

Abstract

The utility model discloses a shell used for a power battery and the power battery, the shell comprises a side wall, a first pressure relief notch groove and a second pressure relief notch groove are arranged on the side wall, a first pressure relief valve is formed on the side wall by means of the first pressure relief notch groove, a second pressure relief valve is formed on the side wall by means of the second pressure relief notch groove, and the first pressure relief valve and the second pressure relief valve are arranged on the side wall by means of the first pressure relief notch groove and the second pressure relief notch groove. The valve opening pressure of the second pressure release valve is larger than that of the first pressure release valve. According to the embodiment of the utility model, the first pressure release valve and the second pressure release valve are arranged on the side wall of the shell, so that the problems that explosion is easy to occur and other batteries are on fire in a linkage manner / a circuit board is damaged due to the fact that only the pressure release valves can be arranged on the top cover of the battery can be solved; in addition, the first pressure release valve and the second pressure release valve can be opened in a step-by-step response manner, so that the reliability of valve opening and pressure release is improved, and the safety of the power battery module can be further improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a housing for a power battery and a power battery. Background Art

[0002] At present, lithium-ion / sodium-ion cylindrical power batteries have gradually become the mainstream products in the new energy industry due to their high energy density, good capacity consistency, and ability to support high-rate charge and discharge. While more and more manufacturers are continuously improving the energy density of cylindrical power batteries, they are also continuously pursuing their high safety. Common problems:

[0003] Generally, for cylindrical power batteries, resistance welding connection or bottom penetration welding of the battery bottom is given priority, so the pressure relief valve can only be set on the top cover. For the thin and long cylindrical power battery, only a small-sized pressure relief valve can be set. When the battery is undergoing short-circuit or high-temperature storage tests, it cannot open the valve in time to relieve pressure and exhaust gas, and it is easy to have an explosion problem, bringing safety risks to customers.

[0004] When a pressure relief valve is set on the surface of the end top cover of a cylindrical power battery, when the valve opens violently to relieve pressure, the internal components of the battery may be directly blown out, triggering chain fires of other batteries / damage to circuit boards, etc., bringing unknown safety risks to the power battery module. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a housing for a power battery and a power battery, which can solve at least one of the technical problems in the above background art.

[0006] To achieve the above purpose, the utility model provides a housing for a power battery. The housing includes a side wall, on which a first pressure relief notch groove and a second pressure relief notch groove are formed. By forming the first pressure relief notch groove, a first pressure relief valve is formed on the side wall. By forming the second pressure relief notch groove, a second pressure relief valve is formed on the side wall. The opening pressure of the second pressure relief valve is greater than that of the first pressure relief valve.

[0007] Optionally, the first pressure relief notch groove has a uniform grooving depth, the second pressure relief notch groove has a uniform grooving depth, and the grooving depth of the second pressure relief notch groove is less than that of the first pressure relief notch groove.

[0008] Optionally, the first pressure relief notch groove is an unclosed notch groove; and / or

[0009] The second pressure relief notch groove is an unclosed notch groove.

[0010] Optionally, the first pressure relief notch groove is C-shaped or X-shaped; and / or

[0011] The second pressure relief notch groove is of C type or X type.

[0012] Optionally, the side wall is cylindrical.

[0013] Optionally, the first pressure relief notch groove and the second pressure relief notch groove are arranged at intervals along the axial direction of the side wall.

[0014] Optionally, the first pressure relief notch groove and the second pressure relief notch groove are arranged axially opposite to each other along the side wall.

[0015] Optionally, the opening pressure of the second pressure relief valve is 1.01 - 1.20 times that of the first pressure relief valve.

[0016] Optionally, the housing is a steel shell or an aluminum shell.

[0017] To achieve the above object, the present utility model provides a power battery, including the housing as described above.

[0018] In the embodiment of the present utility model, a first pressure relief notch groove and a second pressure relief notch groove are provided on the side wall of the housing. By providing the first pressure relief notch groove, a first pressure relief valve is formed on the side wall. By providing the second pressure relief notch groove, a second pressure relief valve is formed on the side wall. The opening pressure of the second pressure relief valve is greater than that of the first pressure relief valve. Since the opening pressure of the second pressure relief valve is greater than that of the first pressure relief valve, the first pressure relief valve and the second pressure relief valve respectively form a primary pressure relief valve and a secondary pressure relief valve. When an extreme situation (such as short circuit, high-temperature storage test or other abnormalities) occurs inside the power battery and the large air pressure generated instantaneously inside the battery reaches the opening pressure of the first pressure relief valve, the first pressure relief valve will quickly open for pressure relief under the impact of the air pressure. If the first pressure relief valve fails to open in time due to some reasons, when the air pressure inside the battery further increases to the opening pressure of the second pressure relief valve, the second pressure relief valve will quickly open for pressure relief under the impact of the air pressure. Thus, it can be seen that in the embodiment of the present utility model, by providing the first pressure relief valve and the second pressure relief valve on the side wall of the housing, not only can the problems such as easy explosion and other battery chain fires / circuit board damage caused by only providing a pressure relief valve on the battery cover be solved, but also the reliability of opening the valve for pressure relief can be improved by the step-by-step response opening of the first pressure relief valve and the second pressure relief valve, and further the safety of the power battery module can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a three-dimensional structural schematic diagram of the housing in the embodiment of the present utility model.

[0020] Figure 2 is Figure 1 a structural schematic diagram of another perspective of the housing in

[0021] Figure 3 is Figure 2 the sectional view taken along line A-A in

[0022] Figure 4 is Figure 3 the enlarged view of part B in

[0023] Figure 5 the schematic perspective view of the housing of another embodiment of the present utility model. Detailed implementation manners

[0024] To make the above objects, features and advantages of the present utility model more obvious and understandable, the following will describe in detail the detailed implementation manners of the present utility model with reference to the accompanying drawings. Many specific details are set forth in the following description in order to fully understand the present utility model. However, the present utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present utility model. Therefore, the present utility model is not limited by the specific embodiments disclosed below.

[0025] Please refer to Figures 1 to 5 , an embodiment of the present utility model discloses a housing 1 for a power battery. The housing 1 includes a side wall 10, on which a first pressure relief notch groove 11 and a second pressure relief notch groove 12 are formed. By forming the first pressure relief notch groove 11, a first pressure relief valve 13 is formed on the side wall 10. By forming the second pressure relief notch groove 12, a second pressure relief valve 14 is formed on the side wall 10. The opening pressure of the second pressure relief valve 14 is greater than that of the first pressure relief valve 13.

[0026] In the embodiments of the present utility model, a first pressure relief notch groove 11 and a second pressure relief notch groove 12 are formed on the side wall 10 of the housing 1. By forming the first pressure relief notch groove 11, a first pressure relief valve 13 is formed on the side wall 10. By forming the second pressure relief notch groove 12, a second pressure relief valve 14 is formed on the side wall 10. The opening pressure of the second pressure relief valve 14 is greater than that of the first pressure relief valve 13. Since the opening pressure of the second pressure relief valve 14 is greater than that of the first pressure relief valve 13, the first pressure relief valve 13 and the second pressure relief valve 14 respectively form a primary pressure relief valve and a secondary pressure relief valve. When an extreme situation (such as short circuit, high-temperature storage test or other abnormalities) occurs inside the power battery, when the large air pressure instantaneously generated inside the battery reaches the opening pressure of the first pressure relief valve 13, the first pressure relief valve 13 will quickly open under the impact of the air pressure for pressure relief. If the first pressure relief valve 13 fails to open in time due to some reasons, when the air pressure inside the battery further increases to the opening pressure of the second pressure relief valve 14, the second pressure relief valve 14 will quickly open under the impact of the air pressure for pressure relief. Thus, in the embodiments of the present utility model, by providing the first pressure relief valve 13 and the second pressure relief valve 14 on the side wall 10 of the housing 1, not only can the problems such as easy explosion and triggering of other battery chain fires / circuit board damage caused by only providing a pressure relief valve on the battery top cover be solved, but also the reliability of opening the valve for pressure relief can be improved by the step-by-step response opening of the first pressure relief valve 13 and the second pressure relief valve 14, and further the safety of the power battery module can be improved.

[0027] In some embodiments, the first pressure relief notch groove 11 has a consistent grooving depth, and the second pressure relief notch groove 12 has a consistent grooving depth. The grooving depth of the second pressure relief notch groove 12 is less than that of the first pressure relief notch groove 11. It should be noted that the first pressure relief notch groove 11 having a consistent grooving depth means that the depths of all positions of the first pressure relief notch groove 11 along its extending direction are basically the same, and the second pressure relief notch groove 12 having a consistent grooving depth means that the depths of all positions of the first pressure relief notch groove 11 along its extending direction are basically the same.

[0028] Since the grooving depth of the second pressure relief notch groove 12 is less than that of the first pressure relief notch groove 11, the thickness T2 of the notch position corresponding to the second pressure relief notch groove 12 is greater than the thickness T1 of the notch position corresponding to the first pressure relief notch groove 11, so that the opening pressure of the second pressure relief valve 14 is greater than that of the first pressure relief valve 13.

[0029] Certainly, in the embodiments of the present utility model, there is no limitation that the first pressure relief notch groove 11 / the second pressure relief notch groove 12 has a consistent grooving depth, as long as the opening pressure of the second pressure relief valve 14 can be made greater than that of the first pressure relief valve 13.

[0030] In some embodiments, the first pressure relief notch groove 11 is an unclosed notch groove. That is to say, the first pressure relief notch groove 11 does not form a closed loop. When the valve is opened, the first pressure relief valve 13 can be opened around the side wall 10, and the first pressure relief valve 13 will not break away from the side wall 10.

[0031] In some embodiments, the second pressure relief notch groove 12 is an unclosed notch groove. That is to say, the second pressure relief notch groove 12 does not form a closed loop. When the valve is opened, the second pressure relief valve 14 can be opened around the side wall 10, and the second pressure relief valve 14 will not break away from the side wall 10.

[0032] Please refer to Figure 1 and Figure 2 , in some embodiments, the first pressure relief notch groove 11 is C-shaped. When the valve is opened, the first pressure relief valve 13 can be opened around the side wall 10, and the first pressure relief valve 13 will not break away from the side wall 10.

[0033] Please refer to Figure 1 and Figure 2 , in some embodiments, the second pressure relief notch groove 12 is C-shaped. When the valve is opened, the second pressure relief valve 14 can be opened around the side wall 10, and the second pressure relief valve 14 will not break away from the side wall 10.

[0034] Please refer to Figure 5 , in some embodiments, the first pressure relief notch groove 11 is X-shaped. When the valve is opened, the two side portions of the first pressure relief valve 13 can be opened to both sides around the side wall 10 respectively, and the first pressure relief valve 13 will not break away from the side wall 10.

[0035] Please refer to Figure 5 , in some embodiments, the second pressure relief notch groove 12 is X-shaped. When the valve is opened, the two side portions of the second pressure relief valve 14 can be opened to both sides around the side wall 10 respectively, and the second pressure relief valve 14 will not break away from the side wall 10.

[0036] Of course, the shapes of the first pressure relief notch groove 11 and the second pressure relief notch groove 12 are not limited to the above-mentioned C shape or X shape, and the shapes of the first pressure relief notch groove 11 and the second pressure relief notch groove 12 are not limited to be the same. As long as the first pressure relief valve 13 and the second pressure relief valve 14 can be formed by opening the first pressure relief notch groove 11 and the second pressure relief notch groove 12 and the opening pressure of the second pressure relief valve 14 is greater than the opening pressure of the second pressure relief valve 14, it is okay.

[0037] In some embodiments, the side wall 10 is cylindrical.

[0038] When the side wall 10 is cylindrical, the opening directions of the aforementioned C-shaped structure and X-shaped structure are preferably circumferential to the side wall 10 for easy processing. But it is not limited to this.

[0039] Specifically, the first pressure relief notch groove 11 and the second pressure relief notch groove 12 are arranged at intervals along the axial direction of the side wall 10. Through this arrangement, it is convenient to open the first pressure relief notch groove 11 and the second pressure relief notch groove 12 when the circumferential dimension of the side wall 10 is limited. Of course, the opening of the first pressure relief notch groove 11 and the second pressure relief notch groove 12 is not limited to this.

[0040] More specifically, the first pressure relief notch groove 11 and the second pressure relief notch groove 12 are arranged axially opposite to each other along the side wall 10, but are not limited to this.

[0041] It should be noted that when the first pressure relief notch groove 11 and the second pressure relief notch groove 12 are arranged at intervals along the axial direction of the side wall 10, the up-and-down (axial) positional relationship between the two is not restricted.

[0042] In some embodiments, the opening pressure of the second pressure relief valve 14 is 1.01 to 1.20 times that of the first pressure relief valve 13. However, it is not limited to this.

[0043] In some embodiments, the housing 1 is a steel housing or an aluminum housing. However, it is not limited to this.

[0044] The embodiment of the present utility model also discloses a power battery, and the power battery includes the housing 1 as described above. A wound core (not shown in the figure) etc. can be arranged inside the housing 1. The housing 1 can be of a structure form with one end closed and the other end open, and a top cover (not shown in the figure) can be arranged at the open end. The housing 1 can also be open at both ends, and cover bodies (not shown in the figure) are respectively arranged at the two open ends.

[0045] Since the opening pressure of the second pressure relief valve 14 is greater than that of the first pressure relief valve 13, the first pressure relief valve 13 and the second pressure relief valve 14 respectively form a primary pressure relief valve and a secondary pressure relief valve. When an extreme situation (such as short circuit, high-temperature storage test or other abnormalities) occurs inside the power battery and the large air pressure instantaneously generated inside the battery reaches the opening pressure of the first pressure relief valve 13, the first pressure relief valve 13 will quickly open for pressure relief under the impact of the air pressure. If the first pressure relief valve 13 fails to open in time due to some reasons, when the air pressure inside the battery further increases to the opening pressure of the second pressure relief valve 14, the second pressure relief valve 14 will quickly open for pressure relief under the impact of the air pressure. Thus, it can be seen that in the embodiment of the present utility model, by arranging the first pressure relief valve 13 and the second pressure relief valve 14 on the side wall 10 of the housing 1, not only can the problems such as easy explosion and triggering of other battery chain fires / circuit board damage caused by only arranging the pressure relief valve on the battery top cover be solved, but also the reliability of opening the valve for pressure relief can be improved by the step-by-step response of the first pressure relief valve 13 and the second pressure relief valve 14 to open the valve, and further the safety of the power battery module can be improved.

[0046] The above-disclosed are only the preferred examples of the present utility model, which are used to facilitate the understanding and implementation by those skilled in the art. Certainly, the scope of rights of the present utility model cannot be limited thereby. Therefore, equivalent changes made according to the scope of the patent application of the present utility model still fall within the scope covered by the present utility model.

Claims

1. A housing for a power battery, characterized in that: The shell includes a side wall, and a first pressure relief notch groove and a second pressure relief notch groove are opened on the side wall. A first pressure relief valve is formed on the side wall due to the opening of the first pressure relief notch groove, and a second pressure relief valve is formed on the side wall due to the opening of the second pressure relief notch groove. The opening pressure of the second pressure relief valve is greater than the opening pressure of the first pressure relief valve.

2. The housing for a power battery according to claim 1, characterized in that: The first pressure relief score groove has a uniform groove depth, the second pressure relief score groove has a uniform groove depth, and the groove depth of the second pressure relief score groove is less than the groove depth of the first pressure relief score groove.

3. The housing for a power battery according to claim 1, characterized in that: The first pressure relief notch is an unclosed notch; and / or The second pressure relief notch groove is an unclosed notch groove.

4. The housing for a power battery according to claim 1, characterized in that: The first pressure relief notch groove is C-shaped or X-shaped; and / or The second pressure relief notch groove is C-shaped or X-shaped.

5. The housing for a power battery according to claim 1, characterized in that: The side wall is cylindrical.

6. The housing for a power battery according to claim 5, characterized in that: The first pressure relief score groove and the second pressure relief score groove are spaced apart in an axial direction of the side wall.

7. The housing for a power battery according to claim 6, characterized in that: The first pressure relief notch groove and the second pressure relief notch groove are arranged opposite to each other along the axial direction of the side wall.

8. The housing for a power battery according to claim 1, characterized in that: The valve opening pressure of the second pressure relief valve is 1.01 to 1.20 times the valve opening pressure of the first pressure relief valve.

9. The housing for a power battery according to claim 1, characterized in that: The shell is a steel shell or an aluminum shell.

10. A power battery, characterized in that: Comprising a housing as claimed in any one of claims 1 to 9.

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