End cover structure and battery cell

Abstract

The utility model relates to the technical field of batteries, in particular to an end cover structure and a battery cell, the end cover structure comprises a cover plate and an anti-explosion valve, the cover plate comprises a flow blocking concave part and an anti-explosion opening used for arranging the anti-explosion valve, and the anti-explosion opening penetrates through the cover plate in the first direction. The flow blocking concave part is arranged at the anti-explosion opening, and at least part of the anti-explosion opening is blocked by the flow blocking concave part when the anti-explosion opening is observed in the first direction. The flow blocking concave part is concave towards the interior of the battery cell, so that at least part of the outer side surface of the flow blocking concave part is positioned on the inner side of the cover plate, and an air passing gap is formed between the at least part of the outer side surface of the flow blocking concave part and the inner side surface of the cover plate. According to the end cover structure and the battery cell provided by the invention, the smoothness of discharging gas in the battery cell is ensured, so that the effectiveness of the anti-explosion valve is ensured, the electrolyte in the battery cell is effectively prevented from directly impacting the anti-explosion valve, and the problems that the anti-explosion valve is opened in advance and fails, the battery cell leaks liquid and the like due to the fact that the electrolyte breaks through the anti-explosion valve are avoided.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and in particular, to an end cap structure and an electric core. Background Art

[0002] With the development of battery technology, the energy storage capacity of batteries has gradually increased, and the capacity of the electrolyte loaded inside the electric core has gradually increased. And currently, an explosion-proof valve is usually provided on the battery top cover for the electric core. To ensure the safety during the use of the battery, a thinning area is usually provided on the explosion-proof valve to facilitate the breakthrough of high-pressure gas.

[0003] Currently, a cavity is formed between the inner end plate of the electric core and the explosion-proof valve. To ensure the exhaust effectiveness of the explosion-proof valve, an exhaust hole communicating with the inside of the electric core needs to be left in the cavity. This makes the electrolyte inside the electric core easily accumulate in the cavity through the exhaust hole. Once the battery faces vibrations, shakes, collisions, drops and other situations, the excess electrolyte inside the electric core and / or the electrolyte accumulated in the cavity will impact the electric core housing from the inside. Once it impacts the thinning area of the explosion-proof valve, it is extremely easy to break through the explosion-proof valve, resulting in problems such as premature opening failure of the explosion-proof valve and leakage of the electric core. Summary of the Utility Model

[0004] The purpose of the present application is to provide an end cap structure and an electric core, so as to solve to a certain extent the technical problems in the prior art that once the battery faces vibrations, shakes, collisions, drops and other situations, the excess electrolyte inside the electric core and / or the electrolyte accumulated in the cavity will impact the electric core housing from the inside. Once it impacts the thinning area of the explosion-proof valve, it is extremely easy to break through the explosion-proof valve, resulting in premature opening failure of the explosion-proof valve and leakage of the electric core.

[0005] According to a first aspect of the present application, an end cap structure for an electric core is provided. The end cap structure includes a cover plate and an explosion-proof valve. The cover plate includes a flow-blocking concave portion and an explosion-proof opening for arranging the explosion-proof valve. The explosion-proof opening penetrates through the cover plate along a first direction;

[0006] The explosion-proof valve is covered on the explosion-proof opening from the outside of the flow-blocking concave portion;

[0007] The flow-blocking concave portion is arranged at the explosion-proof opening, and at least part of the explosion-proof opening is blocked by the flow-blocking concave portion along the first direction;

[0008] The flow-blocking concave portion is recessed into the inside of the electric core, so that at least part of the outer surface of the flow-blocking concave portion is located inside the cover plate, so that at least part of the outer surface of the flow-blocking concave portion and the inner surface of the cover plate are staggered in the first direction to form a gas passage gap.

[0009] Preferably, the end cap structure further includes a connecting edge, the connecting edge is arranged along the inner wall of the explosion-proof port, and the explosion-proof valve is fixedly connected to the connecting edge.

[0010] Preferably, the connecting edge extends a predetermined width s from the inner wall of the explosion-proof port towards the center of the explosion-proof port, where 0.5 mm ≤ s ≤ 3 mm.

[0011] Preferably, the end cap structure further includes a supporting edge, the supporting edge is fixedly arranged at one end of the connecting edge close to the inner side of the battery cell in the first direction, and at least a part of the supporting edge protrudes from the inner wall of the connecting edge towards the middle of the explosion-proof port to support the explosion-proof valve.

[0012] Preferably, in the first direction, the distance between the surface of the supporting edge supporting the explosion-proof valve and the outer surface of the flow-blocking recess is t, where 0.2 mm ≤ t ≤ 2 mm.

[0013] Preferably, along the first direction, the area of the explosion-proof port is larger than the area of the flow-blocking recess.

[0014] Preferably, the flow-blocking recess is further provided with ventilation holes, and the ventilation holes penetrate through the flow-blocking recess along the first direction.

[0015] Preferably, the end cap structure further includes a lower plastic part, and the lower plastic part is arranged inside the cover plate;

[0016] The lower plastic part includes an insulating body and an exhaust part connected to each other, the exhaust part and the explosion-proof port are arranged opposite to each other along the first direction, and the exhaust part is provided with an exhaust hole penetrating through the lower plastic part along the first direction.

[0017] Preferably, in the first direction, the size of the insulating body is larger than the size of the exhaust part.

[0018] According to a second aspect of the present application, there is provided a battery cell including the end cap structure according to any one of the above technical solutions. Therefore, it has all the beneficial technical effects of this end cap structure and will not be elaborated here.

[0019] Compared with the prior art, the beneficial effects of the present application are as follows:

[0020] The end cover structure provided in the present application can effectively prevent the electrolyte inside the battery cell from directly impacting the explosion-proof valve by covering at least part of the explosion-proof opening with a flow-blocking recess arranged on the explosion-proof opening, thereby preventing the electrolyte from breaking through the explosion-proof valve, causing the explosion-proof valve to fail to open prematurely, the battery cell to leak, and other problems; and by recessing the flow-blocking recess into the battery cell, so that at least part of the outer surface of the flow-blocking recess is located on the inner side of the cover plate, so that at least part of the outer surface of the flow-blocking recess and the inner surface of the cover plate are staggered from each other in a first direction to form a gas gap, thereby ensuring the smooth discharge of gas inside the battery cell, thereby ensuring the effectiveness of the explosion-proof valve.

[0021] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 A schematic diagram of the exploded structure of the end cover structure provided in an embodiment of the present application;

[0024] Figure 2 for Figure 1 An enlarged schematic diagram of the end cap structure at position A is provided;

[0025] Figure 3 A schematic diagram of another exploded structure of the end cover structure provided in an embodiment of the present application;

[0026] Figure 4 for Figure 3 An enlarged schematic diagram of the end cap structure at position B is provided;

[0027] Figure 5 A schematic diagram of the front view of the end cover structure provided in an embodiment of the present application;

[0028] Figure 6 for Figure 5 A schematic diagram of a cross-sectional structure obtained by cutting the end cap structure along the CC direction;

[0029] Figure 7 A schematic diagram of the explosion structure of a battery cell provided in an embodiment of the present application.

[0030] Reference numerals:

[0031] 1 - Cover plate; 11 - Explosion - proof port; 12 - Flow - blocking recess; 13 - Connecting edge; 14 - Supporting edge; 2 - Lower plastic part; 21 - Exhaust part; 211 - Exhaust hole; 22 - Insulating body; 3 - Explosion - proof valve; 4 - Terminal post; 5 - End plate; 6 - Housing.

[0032] F1 - First direction; F2 - Second direction; F3 - Third direction. Detailed implementation manners

[0033] The technical solutions of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present application.

[0034] Generally, the components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the present application claimed, but merely represents the selected embodiments of the present application.

[0035] All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the protection scope of the present application.

[0036] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present application. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0037] In the description of the present application, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", "connected" 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 directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0038] Next, refer to Figures 1 to 7 Describe the end - cover structure and the battery cell according to some embodiments of the present application.

[0039] See Figures 1 to 7As shown, an embodiment of the first aspect of the present application provides an end cap structure for an electric core. The end cap structure includes a cover plate 1 and an explosion-proof valve 3. The cover plate 1 includes a flow-blocking recess 12 and an explosion-proof opening 11 for arranging the explosion-proof valve 3. The explosion-proof opening 11 penetrates the cover plate 1 along the first direction F1. The explosion-proof valve 3 is covered on the explosion-proof opening 11 from the outside of the flow-blocking recess 12. The flow-blocking recess 12 is arranged at the explosion-proof opening 11, and along the first direction F1, at least part of the explosion-proof opening 11 is blocked by the flow-blocking recess 12. The flow-blocking recess 12 is recessed into the electric core, so that at least part of the outer surface of the flow-blocking recess 12 is located inside the cover plate 1, so that at least part of the outer surface of the flow-blocking recess 12 and the inner surface of the cover plate 1 are staggered in the first direction to form a gas passage gap.

[0040] According to the end cap structure provided by the above technical features, by arranging the flow-blocking recess 12 at the explosion-proof opening 11 to block at least part of the explosion-proof opening 11, it can effectively prevent the electrolyte inside the electric core from directly impacting the explosion-proof valve 3, thereby avoiding problems such as the electrolyte breaking through the explosion-proof valve 3, resulting in the premature opening failure of the explosion-proof valve 3 and the leakage of the electric core; and by recessing the flow-blocking recess 12 into the electric core, at least part of the outer surface of the flow-blocking recess 12 is located inside the cover plate 1. In this way, at least part of the outer surface of the flow-blocking recess 12 and the inner surface of the cover plate 1 are staggered from each other in the first direction F1 to form a gas passage gap, ensuring the smooth discharge of the gas inside the electric core, and thus ensuring the effectiveness of the explosion-proof valve 3.

[0041] As Figures 1 to 7 shown, F1 shown in the figure can be an example of the above first direction F1. The above end cap structure can be arranged on one side of the electric core in the first direction F1. Preferably, the above first direction F1 can be parallel to the length direction of the electric core. However, it is not limited thereto, and the above first direction F1 can be adaptively adjusted according to the position where the above end cap structure is arranged on the electric core.

[0042] For the convenience of description, two mutually perpendicular directions on the plane perpendicular to the first direction F1 are respectively defined as the second direction F2 and the third direction F3. F2 shown in the figure can be an example of the above second direction F2, and F3 shown in the figure can be an example of the above third direction F3. Taking the first direction F1 being parallel to the length direction of the electric core as an example, correspondingly, the above second direction F2 can be parallel to the width direction of the electric core, and the above third direction F3 can be parallel to the thickness direction of the electric core.

[0043] Preferably, as Figures 1 to 4 shown, the above flow-blocking recess 12 can be in a sheet shape to facilitate blocking the electrolyte inside the electric core.

[0044] However, without being limited thereto, as long as it can block the electrolyte, the above-mentioned flow-blocking recess 12 is not limited to the above-mentioned sheet shape, and the structure of the flow-blocking recess 12 can also be a bent plate, a curved plate or other irregular plate-like structures.

[0045] Preferably, the above-mentioned flow-blocking recess 12 can be integrally connected to the cover plate 1 to ensure the connection stability between the flow-blocking recess 12 and the cover plate 1.

[0046] Optionally, the above-mentioned cover body can be a polished aluminum plate.

[0047] Optionally, the above-mentioned flow-blocking recess 12 can be formed by stamping a polished aluminum plate.

[0048] Preferably, as Figure 6 shown, both ends of the above-mentioned flow-blocking recess 12 in the third direction F3 can be connected to the cover plate 1 to improve the setting stability of the flow-blocking recess 12 and prevent the flow-blocking recess 12 from being damaged by the electrolyte impact on the explosion-proof valve 3.

[0049] However, without being limited thereto, as long as the setting stability of the flow-blocking recess 12 can be ensured, the connection position between the flow-blocking recess 12 and the cover plate 1 is not limited to both ends of the flow-blocking recess 12 in the third direction F3.

[0050] Preferably, as Figure 2 and Figure 4 shown, when observing along the first direction F1, the area of the above-mentioned explosion-proof port 11 is larger than the area of the flow-blocking recess 12. In this way, there is a part of the explosion-proof port 11 that is not blocked by the flow-blocking recess 12, so as to further improve the exhaust smoothness of the explosion-proof port 11.

[0051] As Figures 1 to 5 shows an example in which the above-mentioned explosion-proof port 11 is a waist-shaped hole extending along the second direction F2. The above-mentioned flow-blocking recess 12 can be arranged in a square sheet shape in the middle of the waist-shaped hole. In this way, the part of the explosion-proof port 11 that is not blocked by the flow-blocking recess 12 is communicated with the above-mentioned gas passing gap, further improving the exhaust smoothness of the explosion-proof port 11.

[0052] Optionally, not shown in the figure, the flow-blocking recess 12 can also be provided with air-permeable holes, and the air-permeable holes penetrate the flow-blocking recess 12 along the first direction F1 to further improve the exhaust smoothness of the explosion-proof port 11.

[0053] Preferably, as Figures 1 to 4 shown, the above-mentioned end cover structure further includes a connecting edge 13, and the connecting edge 13 is arranged along the inner wall of the explosion-proof port 11, and the explosion-proof valve 3 is fixedly connected to the connecting edge 13. In this way, the fixing of the explosion-proof valve 3 is realized.

[0054] Optionally, the above-mentioned explosion-proof valve 3 and the connecting edge 13 can be connected by welding.

[0055] Preferably, as Figures 1 to 4 shown, the above-mentioned connection 13 is arranged around the inner wall of the above-mentioned explosion-proof port 11 to ensure the connection continuity and stability between the explosion-proof valve 3 and the cover plate 1.

[0056] Preferably, as Figure 6 shown, the connection extends a predetermined width s from the inner wall of the explosion-proof port towards the center of the explosion-proof port, where 0.5 mm ≤ s ≤ 3 mm. In this way, on the one hand, since s ≥ 0.5 mm, it can effectively ensure that there is enough space between the explosion-proof valve 3 and the cover plate 1 for welding connection, ensuring the welding stability of both the explosion-proof valve 3 and the cover plate 1; on the other hand, since s ≤ 3 mm, it can effectively ensure the anti-deformation strength of the connection 13.

[0057] Preferably, as Figure 2 shown, the end cover structure may further include a supporting edge 14, and the supporting edge 14 is fixedly arranged at one end of the connection 13 close to the inner side of the battery cell in the first direction F1, and at least a part of the supporting edge 14 protrudes from the inner wall of the connection 13 towards the middle of the explosion-proof port 11 to support the explosion-proof valve 3, thereby improving the accuracy and stability of the setting position of the explosion-proof valve 3 in the first direction F1.

[0058] Preferably, as Figure 2 shown, the above-mentioned supporting edge 14 can be arranged at both ends of the above-mentioned explosion-proof port 11 in the second direction F2 to prevent the supporting edge 14 and the flow-blocking recess 12 from interfering with each other.

[0059] Preferably, as Figure 6 shown, in the first direction F1, the distance between the surface of the supporting edge 14 supporting the explosion-proof valve 3 and the outer surface of the flow-blocking recess 12 is t, where 0.2 mm ≤ t ≤ 2 mm. In this way, on the one hand, since t ≥ 0.2 mm, there is enough spacing between the flow-blocking recess 12 and the explosion-proof valve 3 in the first direction F1, which not only ensures the effectiveness of the explosion-proof valve 3, but also avoids scratching and damaging the explosion-proof valve 3 during the assembly process; on the other hand, since t ≤ 2 mm, it can reduce the stamping processing difficulty of the flow-blocking recess 12.

[0060] In the embodiment, as Figures 1 to 4As shown, the above end cap structure may further include a lower plastic part 2, which is disposed inside the cover plate 1. The lower plastic part 2 includes an insulating body 22 and an exhaust part 21 connected to each other. The exhaust part 21 and the explosion-proof port 11 are oppositely disposed along the first direction F1. The exhaust part 21 is provided with an exhaust hole 211 penetrating the lower plastic part 2 along the first direction F1. Thus, on the one hand, the lower plastic part 2 is disposed inside the cover plate 1, which can effectively insulate the cover plate 1; on the other hand, the exhaust part 21 is disposed at the position corresponding to the explosion-proof port 11 of the lower plastic part 2, which can effectively prevent the lower plastic part 2 from interfering with the exhaust of the explosion-proof port 11 and ensure the smooth exhaust of the explosion-proof valve 3.

[0061] Preferably, as Figure 1 and Figure 3 shown, in the first direction F1, the size of the insulating body 22 is larger than that of the exhaust part 21. Thus, a buffer space can be formed between the exhaust part 21 of the lower plastic part 2 and the cover plate 1. On the one hand, when the gas inside the battery cell enters between the lower plastic part 2 and the cover plate 1 through the gas passing gap, setting this buffer space can effectively reduce the gas pressure and flow rate, and further relieve the exhaust pressure of the explosion-proof valve 3, improving the safety of the battery cell; on the other hand, this buffer space provides a certain storage space for the electrolyte. Once the electrolyte enters between the lower plastic part 2 and the cover plate 1 through the exhaust part 21, the electrolyte can be stored in this buffer space and then seep back into the battery cell through the exhaust part 21, avoiding the electrolyte directly impacting the explosion-proof valve 3.

[0062] Optionally, as Figure 7 shown, the above end cap structure may further include an end plate 5, which is disposed on the side of the lower plastic part 2 facing away from the cover plate 1 to limit the position of the electrode group inside the battery cell.

[0063] The embodiment of the second aspect of the present application further provides a battery cell, including the end cap structure described in any of the above embodiments. Therefore, it has all the beneficial technical effects of this end cap structure and will not be elaborated herein.

[0064] Preferably, as Figure 7 shown, the above battery cell may include a housing 6 and an electrode group. The above end cap structure may be covered on one side of the housing 6 in the first direction F1 to form a space for accommodating the electrode group.

[0065] As Figure 7 shows an example in which the above battery cell is in a cuboid shape. However, it is not limited thereto. The shape of the battery cell is not limited to the cuboid form. The shape of the above battery cell may also be cylindrical, polygonal columnar or other shapes.

[0066] Preferably, as Figure 1 and Figure 5 shown, the above battery cell may further include a terminal post 4, which may be disposed on the above cover plate 1.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An end cap structure for a battery cell, characterized in that: The end cover structure comprises a cover plate and an explosion-proof valve, wherein the cover plate comprises a flow-blocking recess and an explosion-proof opening for arranging the explosion-proof valve, and the explosion-proof opening penetrates the cover plate along a first direction; The explosion-proof valve is provided on the explosion-proof opening from the outer side of the flow-blocking recess; The flow blocking recess is arranged at the explosion-proof opening, and along the first direction, at least a part of the explosion-proof opening is blocked by the flow blocking recess; The flow-blocking recess is recessed toward the interior of the battery cell, so that at least part of the outer surface of the flow-blocking recess is located on the inner side of the cover plate, so that at least part of the outer surface of the flow-blocking recess and the inner surface of the cover plate are staggered in the first direction to form an air gap.

2. The end cap structure according to claim 1, characterized in that: The end cover structure also includes a connecting edge, which is arranged along the inner wall of the explosion-proof opening, and the explosion-proof valve is fixedly connected to the connecting edge.

3. The end cap structure according to claim 2, characterized in that: The connection extends along a predetermined width s from the inner wall of the explosion-proof opening toward the center of the explosion-proof opening, wherein 0.5 mm≤s≤3 mm.

4. The end cap structure according to claim 2, characterized in that: The end cover structure also includes a supporting edge, which is fixedly arranged at one end of the connecting edge in the first direction close to the inner side of the battery core, and at least a portion of the supporting edge protrudes from the inner wall of the connecting edge toward the middle of the explosion-proof opening to support the explosion-proof valve.

5. The end cap structure according to claim 4, characterized in that: In the first direction, the distance between the surface of the supporting edge supporting the explosion-proof valve and the outer surface of the flow blocking recess is t, wherein 0.2 mm≤t≤2 mm.

6. The end cover structure according to any one of claims 1 to 5, characterized in that: Along the first direction, the area of ​​the explosion-proof opening is larger than the area of ​​the flow-blocking recess.

7. The end cover structure according to any one of claims 1 to 5, characterized in that: The flow blocking recess is further provided with an air vent, and the air vent penetrates the flow blocking recess along the first direction.

8. The end cover structure according to any one of claims 1 to 5, characterized in that: The end cover structure further comprises a lower plastic part, and the lower plastic part is arranged on the inner side of the cover plate; The lower plastic part includes an insulating body and an exhaust part connected to each other. The exhaust part and the explosion-proof opening are arranged opposite to each other along the first direction. The exhaust part is provided with an exhaust hole penetrating the lower plastic part along the first direction.

9. The end cap structure according to claim 8, characterized in that: In the first direction, a size of the insulating body is larger than a size of the exhaust portion.

10. A battery cell, characterized in that: The invention comprises the end cover structure according to any one of claims 1 to 9.

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