Bottom cover and shell

Abstract

The utility model relates to the technical field of batteries, and provides a bottom cover and a shell, the bottom cover is provided with at least one ventilation groove, the ventilation groove penetrates through two opposite sides of the bottom cover, and the bottom cover is provided with a first convex part which is arranged at an interval with the ventilation groove. The first protruding parts are used for supporting the battery cell, and the first protruding parts and the ventilation grooves are arranged at intervals, so that on one hand, the opposite area of the battery cell and the first protruding parts can be reduced, on the other hand, the cross sectional area of the ventilation grooves can be increased, gas circulation during thermal runaway of the battery cell is greatly facilitated, and the sensitivity and stability of battery detonation are improved. In addition, the first lug boss is arranged on the bottom cover, so that the bottom cover is welded with the tab of the battery cell, a collector plate can be omitted, and the energy density of the battery using the shell can be improved. And moreover, the battery core is not easy to vibrate in the shell, the phenomenon of pulling the current collecting plate is avoided, and the overcurrent stability can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a bottom cover and a shell. Background Art

[0002] As the capacity of the battery cell increases, the safety requirements of the battery are higher, and the volume of the explosion-proof valve also needs to increase accordingly. However, in the prior art, the pole occupies a large area in the center of the top cover plate, resulting in a limited area of ​​the explosion-proof valve, which results in the explosion-proof valve being insufficient to meet the requirements of higher capacity batteries, and safety problems are prone to occur. To solve the above problems, a Chinese patent with application number 2022226210129 discloses a large cylindrical battery housing and a large cylindrical battery containing it. Among them, the bottom panel of the large cylindrical battery housing includes a support surface and a middle opening, the middle opening is arranged in the center of the bottom panel and connected to the inside of the housing, and the explosion-proof valve covers the middle opening. However, the gas flowability of this housing is poor, resulting in the low sensitivity and stability of battery detonation. Utility Model Content

[0003] The utility model aims to provide a bottom cover and a shell, aiming to solve the technical problem that the existing shell is not conducive to the sensitive and stable detonation of the battery.

[0004] In a first aspect, the present application provides a bottom cover, the bottom cover is provided with at least one ventilation groove, the ventilation groove runs through two opposite sides of the bottom cover, and the bottom cover is provided with a first protrusion spaced apart from the ventilation groove.

[0005] Optionally, one first protrusion is provided and is in a ring shape.

[0006] Optionally, at least two first protrusions are provided, and all the first protrusions are arranged at intervals.

[0007] Optionally, the bottom cover includes a body and a boss arranged on the body, the boss and the first protrusion are located on the same side of the body, and the air-permeable groove is arranged on the boss.

[0008] Optionally, the first protrusion protrudes from the boss.

[0009] Optionally, the bottom cover is provided with a first recessed portion, the first recessed portion and the first raised portion are respectively located on two opposite sides of the bottom cover, and the first recessed portion and the first raised portion are correspondingly arranged.

[0010] Optionally, the thickness of the first protrusion is less than or equal to the thickness of the bottom cover.

[0011] Optionally, the bottom cover is provided with a mounting cavity communicated with the air-permeable groove, the mounting cavity and the first protrusion are respectively located on two opposite sides of the bottom cover, and the mounting cavity is used to install the explosion-proof valve.

[0012] Optionally, the bottom cover is provided with a second protrusion, the second protrusion and the first protrusion are located on the same side of the bottom cover and connected to the first protrusion, and the first protrusion protrudes from the second protrusion.

[0013] Optionally, the ventilation groove is opened at the center of the bottom cover.

[0014] Optionally, the ventilation groove is a through hole.

[0015] In a second aspect, the present application provides a shell, including a side wall and the above-mentioned bottom cover, the side wall is hollow, and the bottom cover is integrally formed at one end of the side wall.

[0016] Optionally, an explosion-proof valve is installed at the center of the side of the bottom cover facing away from the side wall, and an air-permeable groove is provided at the center of the side of the bottom cover close to the side wall, wherein the gas acts on the explosion-proof valve through the air-permeable groove.

[0017] The bottom cover provided by the utility model has the following beneficial effects: the first protrusion is used to support the battery cell. By arranging the first protrusion and the air-permeable groove at intervals, on the one hand, the area directly facing the battery cell and the first protrusion can be reduced, and on the other hand, the cross-sectional area of ​​the air-permeable groove can be increased, which greatly facilitates the flow of gas during thermal runaway of the battery cell, and is beneficial to improving the sensitivity and stability of battery detonation. In addition, another purpose of arranging the first protrusion on the bottom cover is to weld it with the pole ear of the battery cell, so that the use of the collector plate can be eliminated, which is beneficial to improving the energy density of the battery using the shell. Moreover, the battery cell is not easy to vibrate inside the shell, and the phenomenon of pulling the collector plate will not occur, which can improve the stability of the overcurrent. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0019] Figure 1 A schematic diagram of the structure of a housing provided in an embodiment of the utility model;

[0020] Figure 2 Another structural schematic diagram of a housing provided in an embodiment of the utility model;

[0021] Figure 3 A cross-sectional view of a housing provided in an embodiment of the utility model;

[0022] Figure 4 Another structural schematic diagram of a housing provided in an embodiment of the utility model;

[0023] Figure 5Another structural schematic diagram of a housing provided in an embodiment of the utility model;

[0024] Figure 6 Another structural schematic diagram of a housing provided in an embodiment of the utility model;

[0025] Figure 7 Another structural schematic diagram of the housing provided in an embodiment of the utility model.

[0026] Among them, the reference numerals in the figure are:

[0027] 100, bottom cover; 10, body; 20, boss;

[0028] 11. Ventilation groove; 12. First protrusion; 13. Installation cavity;

[0029] 14. first concave portion; 15. second convex portion; 16. gas channel;

[0030] 131. first cavity section; 132. second cavity section; 1. housing;

[0031] 200, side wall; 300, explosion-proof valve; 310, valve body;

[0032] 320. Patch. DETAILED DESCRIPTION

[0033] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0034] Reference throughout the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Thus, when the phrases "in one embodiment" or "in some embodiments" appear in various places throughout the specification, not all references are to the same embodiment. Furthermore, in one or more embodiments, the particular features, structures, or characteristics may be combined in any suitable manner.

[0035] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0036] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0037] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral 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, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] Please refer to Figures 1 to 7 Now, the bottom cover 100 and the housing 1 in the embodiment of the utility model are described.

[0039] Please refer to Figure 1 and Figure 2 The present application provides a housing 1, comprising a side wall 200 and a bottom cover 100, wherein the side wall 200 is hollow and the bottom cover 100 is integrally formed at one end of the side wall 200. Specifically, the bottom cover 100 is integrally formed at the lower end of the side wall 200, and compared with welding the bottom cover 100 to the lower end of the side wall 200, the former can improve production efficiency.

[0040] In another embodiment of the present application, please refer to Figure 3, an explosion-proof valve 300 is installed at the center of the side of the bottom cover 100 away from the side wall 200, and a vent groove 11 is provided at the center of the side of the bottom cover 100 close to the side wall 200, wherein the gas acts on the explosion-proof valve 300 through the vent groove 11. Specifically, the explosion-proof valve 300 is installed at the center of the lower surface of the bottom cover 100, and the vent groove 11 is provided at the center of the upper surface of the bottom cover 100, and the explosion-proof valve 300 is directly opposite to the vent groove 11. Such a setting can facilitate the opening of the explosion-proof valve 300, which is conducive to improving the sensitivity and stability of the explosion-proof valve 300. It can be understood that the present housing 1 is suitable for batteries, that is, the side wall 200 is hollowed out to accommodate the battery cell. When the battery has thermal runaway, the gas inside the housing 1 can act on the explosion-proof valve 300 through the vent groove 11, thereby achieving the purpose of internal pressure relief of the battery.

[0041] In addition, no pole is provided on the bottom cover 100. By disposing the explosion-proof valve 300 at the center of the bottom cover 100, the size of the explosion-proof valve 300 is not limited by the pole, so that the explosion-proof valve 300 can meet the use requirements of higher capacity batteries, which is beneficial to improving safety performance.

[0042] As mentioned in the background art, the gas flowability of the existing shell is poor, resulting in low sensitivity and stability of battery detonation.

[0043] To this end, the present application also provides a bottom cover 100. Since the shell 1 provided in the present application adopts such a bottom cover 100, the shell 1 can solve the above-mentioned problem.

[0044] Please refer to Figure 1 and Figure 2 , the bottom cover 100 provided in the present application is provided with at least one venting groove 11, the venting groove 11 passes through the two opposite sides of the bottom cover 100, and the bottom cover 100 is provided with a first protrusion 12 arranged at intervals from the venting groove 11. Specifically, the venting groove 11 is provided on the upper surface of the bottom cover 100 and passes through the lower surface of the bottom cover 100 in the up-down direction. The venting groove 11 is provided on the upper surface of the bottom cover 100 and passes through the bottom cover 100 in the up-down direction to form a through-hole structure. The first protrusion 12 is provided on the upper surface of the bottom cover 100 and is arranged at intervals around the venting groove 11. The first protrusion 12 is used to support the battery cell. By arranging the first protrusion 12 at intervals from the venting groove 11, on the one hand, the area directly facing the battery cell and the first protrusion 12 can be reduced, and on the other hand, the cross-sectional area of ​​the venting groove 11 can be increased, which greatly facilitates the circulation of gas when the battery cell is thermally runaway, and is conducive to improving the sensitivity and stability of battery detonation.

[0045] In addition, another purpose of providing the first protrusion 12 on the bottom cover 100 is to weld it with the tab of the battery cell, so that the use of the collector plate can be eliminated, which is conducive to improving the energy density of the battery using the present housing 1. Moreover, the battery cell is not easy to vibrate inside the housing 1, and the collector plate will not be pulled, which can improve the stability of the current flow.

[0046] In some embodiments, please refer to Figure 1 and Figure 2 The first protrusion 12 is provided with one ring-shaped protrusion 12. The first protrusion 12 surrounds the venting groove 11. Such a configuration is beneficial to improving the stability of the battery cell and the bottom cover 100 after welding.

[0047] In some embodiments, please refer to Figure 4 and Figure 5 , at least two first protrusions 12 are provided, and all the first protrusions 12 are arranged at intervals. Exemplarily, four first protrusions 12 are provided, and the four first protrusions 12 are arranged at intervals and arranged around all the air permeable grooves 11. In this way, a gas channel 16 is formed between two adjacent first protrusions 12, so that the gas inside the housing 1 can enter the air permeable groove 11 through the gas channel 16, effectively improving the gas flowability.

[0048] It is understandable that when the number of the first protrusions 12 is at least two, the cross-sections of the first protrusions 12 may be circular, sector-shaped, or square, etc. In addition, the cross-sections of all the first protrusions 12 are not necessarily exactly the same. For example, the cross-section of one of the first protrusions 12 may be circular, and the cross-section of another first protrusion 12 may be sector-shaped, which is not limited here.

[0049] In another embodiment of the present application, please refer to Figure 2 The bottom cover 100 includes a body 10 and a boss 20 disposed on the body 10, the boss 20 and the first protrusion 12 are located on the same side of the body 10, and the air-permeable groove 11 is disposed on the boss 20. Specifically, the boss 20 and the first protrusion 12 are both disposed on the upper surface of the body 10, and the first protrusion 12 surrounds the boss 20 and is spaced apart from the boss 20. The air-permeable groove 11 is disposed at the center of the upper surface of the boss 20, and penetrates to the lower surface of the body 10 in the up-down direction, and the explosion-proof valve 300 is disposed at the center of the lower surface of the body 10. Generally, the bottom cover 100 is thin as a whole. The boss 20 is disposed at the center of the body 10, and the thickness at the center of the bottom cover 100 can be increased to facilitate the installation of the explosion-proof valve 300. In this way, the thickness of the remaining parts of the body 10 does not need to be increased, which is conducive to achieving lightweight housing 1.

[0050] In another embodiment of the present application, please refer to Figure 3The first protrusion 12 protrudes from the boss 20, that is, in the up-down direction, the top surface of the first protrusion 12 is located above the top surface of the boss 20. This arrangement allows a gap to exist between the battery cell and the boss 20, which can improve the flowability of the gas inside the housing 1.

[0051] In another embodiment of the present application, please refer to Figures 1 to 3 The bottom cover 100 is provided with a first recessed portion 14, and the first recessed portion 14 and the first raised portion 12 are respectively located on two opposite sides of the bottom cover 100, and the first recessed portion 14 and the first raised portion 12 are provided correspondingly. Specifically, the first recessed portion 14 is provided on the lower surface of the bottom cover 100. The provision of the first recessed portion 14 is conducive to achieving lightweight of the housing 1.

[0052] In some embodiments, the first recessed portion 14 and the first raised portion 12 are integrally formed on the body 10 by a stamping process, which can improve production efficiency.

[0053] The first protrusion 12 and the first recess 14 are equivalent to a reinforcing rib structure, which can make the wall thickness of the main body 10 smaller, and is conducive to achieving lightweight of the shell 1.

[0054] In another embodiment of the present application, the thickness of the first protrusion 12 is less than or equal to the thickness of the bottom cover 100. Specifically, the first protrusion 12 is formed by a stamping process on the body 10, and the thickness of the first protrusion 12 is less than or equal to the thickness of the body 10. Such a configuration can facilitate welding of the battery cell and the first protrusion 12.

[0055] In another embodiment of the present application, please refer to Figure 2 and Figure 3 The bottom cover 100 is provided with a mounting cavity 13 connected to the air-permeable groove 11. The mounting cavity 13 and the first protrusion 12 are respectively located on two opposite sides of the bottom cover 100. The mounting cavity 13 is used to install the explosion-proof valve 300. Specifically, the mounting cavity 13 is arranged at the center of the lower surface of the body 10, that is, the explosion-proof valve 300 is installed at the center of the lower surface of the body 10, which is conducive to improving the sensitivity and stability of the explosion-proof valve 300.

[0056] In another embodiment of the present application, please refer to Figure 2 and Figure 3The installation cavity 13 includes a first cavity section 131 and a second cavity section 132. The first cavity section 131 is opened at the center of the lower surface of the body 10, and the second cavity section 132 is opened on the upper wall of the first cavity section 131. The air-permeable groove 11 is connected with the second cavity section 132. The explosion-proof valve 300 includes a valve body 310 and a patch 320. The valve body 310 is welded in the second cavity section 132, and the patch 320 is attached to the first cavity section 131. In the up and down direction, the length of the first cavity section 131 is greater than the length of the patch 320, so as to avoid the patch 320 protruding from the first cavity section 131, causing the housing 1 to be uneven when placed, and reduce the risk of damage to the patch 320. The gap between the second cavity section 132 and the valve body 310 is less than 0.2 mm. Preferably, the gap between the second cavity section 132 and the valve body 310 is 0.03-0.1 mm, such as 0.03 mm, 0.05 mm, 0.07 mm, 1 mm, etc., to facilitate welding of the valve body 310. It is worth mentioning that the upper wall surface of the second cavity section 132 does not penetrate the collector plate, so that the valve body 310 can avoid being crushed by foreign objects such as the battery cell or the collector plate.

[0057] In another embodiment of the present application, please refer to Figure 6 and Figure 7 , the bottom cover 100 is provided with a second protrusion 15, the second protrusion 15 and the first protrusion 12 are located on the same side of the bottom cover 100, and are connected to the first protrusion 12, and the first protrusion 12 protrudes from the second protrusion 15. Specifically, the first protrusion 12 and the second protrusion 15 are both provided on the upper surface of the body 10. In the up and down direction, the top surface of the first protrusion 12 is located above the top surface of the second protrusion 15. In other words, after the battery cell is welded to the first protrusion 12, there is a gap between the battery cell and the second protrusion 15, that is, the second protrusion 15 will not interfere with the welding of the battery cell and the first protrusion 12. The provision of the second protrusion 15 is conducive to improving the strength of the first protrusion 12.

[0058] In some embodiments, the second protrusion 15 is connected to a side of the first protrusion 12 away from the vent groove 11. Of course, in other embodiments, the second protrusion 15 may also be connected to a side of the first protrusion 12 close to the vent groove 11.

[0059] It is understandable that the number of the first protrusions 12 and the second protrusions 15 may be the same or different, which is not limited here. In this embodiment, the number of the first protrusions 12 and the second protrusions 15 is the same. For example, please refer to Figure 6 and Figure 7, the number of the first protrusions 12 and the number of the second protrusions 15 are both four. The four first protrusions 12 are arranged around all the air-permeable grooves 11, and a second protrusion 15 is arranged between two adjacent first protrusions 12, and the adjacent first protrusions 12 and second protrusions 15 are connected to each other. In this way, the second protrusions 15 can not only improve the strength of the first protrusions 12, but also form a gas channel 16, which facilitates the opening of the explosion-proof valve 300, greatly improving the practicality and functionality of the bottom cover 100.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A bottom cover, characterized in that: The bottom cover (100) is provided with at least one venting groove (11), the venting groove (11) runs through two opposite sides of the bottom cover (100), and the bottom cover (100) is provided with a first protruding portion (12) spaced apart from the venting groove (11).

2. The bottom cover according to claim 1, characterized in that: The first protrusion (12) is provided with one and is in a ring shape; Alternatively, at least two first protrusions (12) are provided, and all of the first protrusions (12) are arranged at intervals.

3. The bottom cover according to claim 1, characterized in that: The bottom cover (100) comprises a body (10) and a boss (20) arranged on the body (10); the boss (20) and the first protruding portion (12) are located on the same side of the body (10); and the venting groove (11) is arranged on the boss (20).

4. The bottom cover according to claim 3, characterized in that: The first protruding portion (12) protrudes from the boss (20).

5. The bottom cover according to claim 1, characterized in that: The bottom cover (100) is provided with a first recessed portion (14), the first recessed portion (14) and the first raised portion (12) are respectively located on two opposite sides of the bottom cover (100), and the first recessed portion (14) and the first raised portion (12) are arranged correspondingly; The thickness of the first protruding portion (12) is less than or equal to the thickness of the bottom cover (100).

6. The bottom cover according to claim 1, characterized in that: The bottom cover (100) is provided with a mounting cavity (13) communicating with the vent groove (11); the mounting cavity (13) and the first protruding portion (12) are respectively located on two opposite sides of the bottom cover (100); and the mounting cavity (13) is used for mounting an explosion-proof valve.

7. The bottom cover according to claim 1, characterized in that: The bottom cover (100) is provided with a second protruding portion (15), the second protruding portion (15) and the first protruding portion (12) are located on the same side of the bottom cover (100) and are connected to the first protruding portion (12), and the first protruding portion (12) protrudes from the second protruding portion (15).

8. The bottom cover according to claim 1, characterized in that: The ventilation groove (11) is opened at the center of the bottom cover (100); And / or, the ventilation groove (11) is a through hole.

9. A housing, characterized in that: It comprises a side wall (200) and a bottom cover (100) according to any one of claims 1 to 8, wherein the side wall (200) is hollow, and the bottom cover (100) is integrally formed at one end of the side wall (200).

10. The housing according to claim 9, characterized in that: An explosion-proof valve (300) is installed at the center of the side of the bottom cover (100) facing away from the side wall (200), and a ventilation groove (11) is provided at the center of the side of the bottom cover (100) close to the side wall (200), wherein gas acts on the explosion-proof valve (300) through the ventilation groove (11).

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