A top cover structure and a battery

Abstract

The utility model discloses a top cap structure and battery, including rivet and the lower plastic, light cover plate, upper plastic and connecting terminal that are pressed together from below to above through rivet, wherein, first boss is provided between light cover plate with upper plastic, second boss is provided between upper plastic with connecting terminal. In this top cap structure and battery, boss design forms the physical barrier, can avoid the outside electrolyte infiltration pole post inside and lead to battery performance attenuation, simultaneously still provided axial limiting function, strengthened the mechanical reliability and stability of battery top cap structure.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a top cover structure and a battery. Background Technology

[0002] Batteries, as important energy storage devices, are widely used in consumer electronics, electric vehicles, energy storage systems, and other fields. The battery top cover, as a key component of battery packaging, not only needs to ensure the battery's sealing performance but also bears the important function of electrode lead-out.

[0003] In existing technologies, battery top cover structures mainly employ two methods: injection molding and riveting. In traditional designs, the surface of the top cover is typically directly bonded to the upper plastic component. This structure presents significant drawbacks during battery manufacturing. During the electrolyte filling process, electrolyte inevitably splashes onto the cover surface and the terminal area. Furthermore, after filling, residual electrolyte on the filling hole walls can easily drip onto the cover surface. Due to the direct bonding design between the top cover surface and the upper plastic component, electrolyte may seep into the terminal through the contact interface, leading to corrosion of metal components and severely impacting the battery's electrochemical performance and safety.

[0004] Furthermore, existing top cover riveting structures mostly use longitudinally pressing rivets for fixation, achieving the connection through the plastic deformation of the rivet material. However, this structure lacks an effective axial restraint mechanism, which may lead to loosening of the connection during battery use, especially when subjected to external forces such as vibration and impact, thereby affecting the structural stability and sealing reliability of the battery. Utility Model Content

[0005] The purpose of this utility model is to provide a top cover structure and battery to prevent battery leakage from causing corrosion of the terminals and affecting battery performance, while also increasing axial restraint and enhancing battery structural stability.

[0006] The objective of this utility model is achieved through the following technical solution: A top cover structure includes rivets and a lower plastic, a smooth cover plate, an upper plastic, and a connecting terminal that are pressed together from bottom to top by the rivets; wherein a first boss is provided between the smooth cover plate and the upper plastic, and a second boss is provided between the upper plastic and the connecting terminal.

[0007] In some alternative embodiments, the first boss and / or the second boss are used to prevent electrolyte from seeping into the interior of the battery terminals from the outside.

[0008] In some alternative solutions, the first boss and / or the second boss are used to axially limit the top cover structure.

[0009] In some alternative designs, both the first boss and the second boss are continuous annular protrusions.

[0010] In some alternative solutions, the first boss is integrally formed on the upper end face of the cover plate, and the lower end face of the upper plastic is provided with a first groove corresponding to the first boss. The second boss is integrally formed on the upper surface of the upper plastic, and the lower surface of the connecting terminal is provided with a second groove corresponding to the second boss.

[0011] In some alternative designs, the first boss and the second boss each have inclined walls.

[0012] In some alternative solutions, the height of the first boss is 0.2-0.5 mm and the width is 0.3-0.8 mm, and the dimensions of the second boss are the same as those of the first boss.

[0013] In some alternative embodiments, the rivet includes a support portion, and a sealing ring is fitted at the bottom of the rivet, the sealing ring being located between the cover plate and the support portion.

[0014] In some alternative solutions, the lower end face of the lower plastic is provided with a first groove that mates with the rivet, and the upper end face of the connecting terminal is provided with a second groove that mates with the rivet.

[0015] In addition, this utility model also provides a battery, including the above-described top cover structure.

[0016] Compared with the prior art, the beneficial effects of this utility model include at least the following: 1. The protrusion design forms a physical barrier, which can prevent external electrolyte from seeping into the inside of the terminal post and causing battery performance degradation. It also provides an axial limiting function, enhancing the mechanical reliability and stability of the battery top cover structure.

[0017] 2. This top cover structure does not require additional parts; only corresponding modifications to the existing mold are needed, which will not significantly increase production costs. Attached Figure Description

[0018] Figure 1 This is a cross-sectional schematic diagram of the top cover structure of this utility model.

[0019] Figure 2 This is a magnified view of a portion of the top cover structure.

[0020] In the diagram: 1. Rivet; 11. Support part; 2. Lower plastic; 21. First groove; 3. Cover plate; 4. Upper plastic; 41. First slot; 5. Connecting terminal; 51. Second slot; 52. Second groove; 6. First boss; 7. Second boss; 8. Sealing ring. Detailed Implementation

[0021] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to make the present invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore repeated descriptions of them will be omitted.

[0022] The terms used to describe position and direction in this utility model are illustrated with the accompanying drawings, but changes can be made as needed, and all such changes are included within the scope of protection of this utility model.

[0023] The battery has a top cover portion comprising rivets 1 and, from bottom to top, a lower plastic 2, a smooth cover plate 3, an upper plastic 4, and connecting terminals 5, all pressed together by the rivets 1. As noted in the background art, during the battery electrolyte filling process, electrolyte inevitably splashes onto the surface of the smooth cover plate 3 and the terminal area. Furthermore, after filling, residual electrolyte on the walls of the filling holes easily drips onto the surface of the smooth cover plate 3. Due to the direct bonding design between the surface of the smooth cover plate 3 and the upper plastic 4, electrolyte may seep into the terminal through the contact interface, leading to corrosion of metal components and severely affecting the battery's electrochemical performance and safety.

[0024] In view of this, this application proposes a top cover structure. Based on the above, a first protrusion 6 is provided between the light cover plate 3 and the upper plastic 4, and a second protrusion 7 is provided between the upper plastic 4 and the connecting terminal 5, so as to prevent battery leakage from causing corrosion of the terminal and affecting battery performance, while forming an axial limit to enhance the stability of the top cover structure.

[0025] See Figure 1 and Figure 2 As shown, in the top cover structure of this application, the first boss 6 is integrally formed on the upper end surface of the cover plate 3, and the lower end surface of the upper plastic 4 is provided with a first groove 41 corresponding to the first boss 6, so as to accommodate and fix the first boss 6; the second boss 7 is integrally formed on the upper end surface of the upper plastic 4, and the lower end surface of the connecting terminal 5 is provided with a second groove 51 corresponding to the second boss 7, so as to accommodate and fix the second boss 7.

[0026] In this structure, the first protrusion 6 and the second protrusion 7 can independently or collaboratively prevent electrolyte from seeping into the battery's terminals from the outside, or they can axially limit the top cover structure. Specifically, the first protrusion 6 and / or the second protrusion 7 can form a raised physical barrier at the corresponding contact interface. When electrolyte drips onto the surface of the cover plate 3, the electrolyte needs to overcome surface tension to "climb" over the small slope formed by the first protrusion 6 and / or the second protrusion 7 at the corresponding contact interface before it can continue to penetrate into the terminal area. This process greatly increases the resistance to electrolyte penetration. On the other hand, after the top cover structure is riveted, the first protrusion 6 is fixed to the first slot 41 and / or the second protrusion 7 is fixed to the second slot 51, forming an axial limiting structure. This can effectively prevent relative displacement of components under vibration or impact conditions, thereby improving the stability and mechanical reliability of the top cover structure.

[0027] Of course, in other embodiments, the first boss 6 may also be integrally formed on the lower end surface of the upper plastic 4, and the upper end surface of the cover plate 3 is provided with a first groove 41 corresponding to the first boss 6; the second boss 7 is integrally formed on the lower end surface of the connecting terminal 5, and the upper end surface of the upper plastic 4 is provided with a second groove 51 (not shown) corresponding to the second boss 7. Alternatively, the first boss 6 and the second boss 7 may each be integrally formed on the lower and upper end surfaces of the upper plastic 4, and the upper end surface of the cover plate 3 is provided with a first groove 41 corresponding to the first boss 6, and the lower end surface of the connecting terminal 5 is provided with a second groove 51 (not shown) corresponding to the second boss 7.

[0028] In some embodiments, the first boss 6 and the second boss 7 are both annular continuous protrusions to ensure circumferential continuity and sealing, enhancing their anti-permeability while also ensuring good limiting effect in all directions. In other embodiments, the first boss 6 and the second boss 7 may also be annular but not continuous protrusions.

[0029] In some embodiments, the first boss 6 and the second boss 7 each have inclined walls to facilitate assembly and positioning with corresponding slots. Furthermore, the inclined walls further increase the length of the ramp path for electrolyte penetration, thereby improving the ability to prevent electrolyte penetration. Preferably, the cross-sections of the first boss 6 and the second boss 7 can be trapezoidal, triangular, or other polygons with inclined sidewalls; no specific limitations are imposed here.

[0030] In some embodiments, the surfaces of the first boss 6 and / or the second boss 7 are provided with a corrosion-resistant layer, which may be a polytetrafluoroethylene coating to further enhance its durability and sealing life.

[0031] In some embodiments, the height of the first boss 6 is 0.2-0.5 mm and the width is 0.3-0.8 mm, and the size of the second boss 7 is the same as or slightly larger than that of the first boss 6. In this application, the height of both the first boss 6 and the second boss 7 is 0.3 mm and the width of both is 0.6 mm. These dimensional parameters achieve a good balance between leak-proof effect and structural strength.

[0032] In some embodiments, the rivet 1 includes a support portion 11, and a sealing ring 8 is sleeved on the bottom of the rivet 1. The sealing ring 8 is located between the cover plate 3 and the support portion 11, and can play a sealing role under full compression to prevent the electrolyte inside the battery from leaking from the inside to the outside.

[0033] In some embodiments, the lower end face of the lower plastic 2 is provided with a first groove 21 that cooperates with the rivet 1, for receiving the support part 11 of the rivet 1 and supporting the bottom of the top cover structure; the upper end face of the connecting terminal 5 is provided with a second groove 52 that cooperates with the rivet 1, the top of the rivet 1 is plastically deformed under pressure and received therein, and the support part 11 is used to fix the top cover structure.

[0034] In some embodiments, the upper plastic 4 and lower plastic 2 can be made of materials with excellent resistance to electrolytes, such as polypropylene and polybutylene terephthalate. The cover plate 3 is preferably made of stainless steel to ensure its good corrosion resistance and mechanical strength. The connecting terminal 5 can be made of aluminum to meet conductivity requirements. During assembly, the lower plastic 2, cover plate 3, upper plastic 4, and connecting terminal 5 are stacked sequentially and rivets 1 are inserted. Then, they are riveted together on a dedicated riveting machine, with the riveting pressure controlled at 2-4 kN and the holding time at 2-3 seconds.

[0035] In summary, the top cover structure of this application forms a physical barrier through the protrusion design, which can prevent external electrolyte from seeping into the inside of the electrode post and causing battery performance degradation. At the same time, it also provides an axial limiting function, which enhances the mechanical reliability and stability of the battery top cover structure.

[0036] It is understandable that this top cover structure cleverly solves two key technical problems of electrolyte permeation and axial restriction in the existing top cover of the battery through a simple boss design. For production, it only requires adding boss and slot structure to the existing mold, without the need to develop a completely new production process. Compared with the traditional top cover structure, the cost increases slightly, but the performance can be significantly improved.

[0037] In addition, this utility model also discloses a battery, such as a circular lithium battery, which includes the above-mentioned top cover structure, so that the top cover of the battery has excellent anti-permeability and axial limiting ability, thereby improving the product performance of the battery.

[0038] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and alterations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention, and all such changes should fall within the protection scope of the claims of the present invention.

Claims

1. A top cover structure, comprising rivets (1) and a lower plastic sheet (2), a smooth cover plate (3), an upper plastic sheet (4), and connecting terminals (5) pressed together from bottom to top by the rivets (1), characterized in that, A first boss (6) is provided between the light cover plate (3) and the upper plastic (4), and a second boss (7) is provided between the upper plastic (4) and the connecting terminal (5).

2. The top cover structure according to claim 1, characterized in that, The first protrusion (6) and / or the second protrusion (7) are used to prevent electrolyte from seeping into the battery terminals from the outside.

3. The top cover structure according to claim 1 or 2, characterized in that, The first boss (6) and / or the second boss (7) are used to axially limit the top cover structure.

4. The top cover structure according to claim 1, characterized in that, Both the first boss (6) and the second boss (7) are continuous annular protrusions.

5. The top cover structure according to claim 1, characterized in that, The first boss (6) is integrally formed on the upper end surface of the light cover plate (3), and the lower end surface of the upper plastic (4) is provided with a first groove (41) corresponding to the first boss (6). The second boss (7) is integrally formed on the upper end surface of the upper plastic (4), and the lower end surface of the connecting terminal (5) is provided with a second groove (51) corresponding to the second boss (7).

6. The top cover structure according to claim 5, characterized in that, The first boss (6) and the second boss (7) each have an inclined wall.

7. The top cover structure according to claim 1, characterized in that, The height of the first boss (6) is 0.2-0.5mm and the width is 0.3-0.8mm. The dimensions of the second boss (7) are the same as those of the first boss (6).

8. The top cover structure according to claim 1, characterized in that, The rivet (1) includes a support portion (11), and a sealing ring (8) is fitted at the bottom of the rivet (1). The sealing ring (8) is located between the cover plate (3) and the support portion (11).

9. The top cover structure according to claim 1, characterized in that, The lower end face of the lower plastic (2) is provided with a first groove (21) that cooperates with the rivet (1), and the upper end face of the connecting terminal (5) is provided with a second groove (52) that cooperates with the rivet (1).

10. A battery, characterized in that, Includes the top cover structure as described in any one of claims 1-9.

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