Battery top cover

Abstract

The utility model provides a battery top cover. The battery top cover comprises a top cover plate; the lower plastic is provided with a first through hole and a second through hole; the pole component comprises an upper pole and a lower pole; the upper pole and the lower pole are connected in a welding manner; the upper plastic is arranged between the top cover plate and the upper pole so as to insulate and separate the upper pole from the top cover plate; the flange part extends outwards from the main body part in the radial direction, and is positioned in a gap between the upper pole and the top cover plate in the vertical direction; and the main body part penetrates through the first post terminal through hole and the first penetrating hole and is positioned on the outer side of the upper post terminal so as to seal a gap between the lower plastic and the upper post terminal. According to the secondary battery top cover disclosed by the utility model, the flange part is arranged at the upper end of the sealing ring, so that the creepage phenomenon between the upper pole and the top cover plate can be prevented, and the safety performance of the battery top cover is improved.

Description

Technical Field

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

[0002] Rechargeable batteries, also known as secondary batteries or accumulators, can be reused after discharging by recharging to reactivate the active materials. This recyclability has made them a primary power source for electrical systems. However, with the rapid development of new energy sources and the influx of companies into the field, fierce competition has led to increasingly stringent cost requirements. Furthermore, for new energy electric vehicles, batteries need to achieve rapid charging in a short time. However, fast charging directly results in high temperatures caused by the large current, necessitating high-temperature resistant battery covers. Therefore, there is an urgent need to develop a low-cost, high-temperature resistant, and cost-effective battery cover.

[0003] Currently, the commonly used battery top covers on the market mainly include traditional pillar top covers, minimalist top covers, riveted top covers, rolled edge top covers, and nano top covers. However, these conventional battery top covers still cannot meet the current market requirements for low cost, high temperature resistance, and high safety, and their respective performance cannot satisfy customer needs. Utility Model Content

[0004] To improve the high-temperature resistance and safety performance of the battery top cover and its battery, while reducing product manufacturing costs, this utility model provides a battery top cover, comprising: a top cover plate having a first terminal through hole and a second terminal through hole; a lower plastic having a first penetrating hole and a second penetrating hole, the lower plastic being configured to connect to the top cover plate; a terminal assembly including an upper terminal and a lower terminal; the upper terminal passes through the first terminal through hole and the first penetrating hole, the upper terminal and the lower terminal are connected by welding; an upper plastic being disposed between the top cover plate and the upper terminal to insulate the upper terminal from the top cover plate; and a sealing ring comprising a main body and a flange extending radially outward from the main body, wherein, in the vertical direction, the flange is located in the gap between the upper terminal and the top cover plate, and the main body passes through the first terminal through hole and the first penetrating hole and is located outside the upper terminal to seal the gap between the lower plastic and the upper terminal.

[0005] Furthermore, the upper pole post includes an upper end, a middle part, and a lower end, wherein the cross-sectional area of ​​the upper end is larger than the cross-sectional area of ​​the middle part, and the cross-sectional area of ​​the middle part is larger than the area of ​​the lower end.

[0006] Furthermore, the sealing ring is made of fluororubber material.

[0007] Furthermore, the upper part is a cuboid, and the middle part and the lower part are cylindrical.

[0008] Furthermore, the upper end is cylindrical.

[0009] Furthermore, the lower electrode post is connected to the lower end of the upper electrode post by welding.

[0010] Furthermore, the bottom of the upper plastic is also provided with an air vent.

[0011] Furthermore, the upper electrode and the lower electrode are made of different metallic materials.

[0012] In summary, the secondary battery top cover of this utility model has a flange at the upper end of the sealing ring, which can prevent creepage between the upper electrode post and the top cover plate, thereby improving the safety performance of the battery top cover. At the same time, the upper electrode post assembly of this utility model is set as a stepped structure from top to bottom, thereby reducing the overall weight of the electrode post and thus the battery top cover. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the battery top cover of this utility model;

[0014] Figure 2 This is an exploded view of the battery top cover of this utility model;

[0015] Figure 3 This is a schematic diagram of the battery top cover of this utility model from another angle;

[0016] Figure 4 This is a schematic diagram of the battery top cover of this utility model from another angle;

[0017] Figure 5 for Figure 4 A partial cross-sectional diagram along line AA;

[0018] Figure 6 This is a schematic diagram of the sealing ring in the battery top cover of this utility model;

[0019] Figure 7 This is a schematic diagram of the upper electrode post in the battery top cover of this utility model;

[0020] Figure 8 This is a schematic diagram of the upper plastic part of the battery top cover of this utility model. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0022] Reference Figures 1-8 The secondary top cover of this utility model includes a top cover plate 30, an upper plastic component 102, a positive terminal assembly 10, a negative terminal assembly 20, a lower plastic component 40, and an explosion-proof component 50. The top cover plate 30 includes a positive terminal through hole 301, a negative terminal through hole 302, and an explosion-proof valve mounting hole 303. The upper plastic component 102 is constructed as follows... Figure 4 As shown, the upper plastic 102 is made of resin material and is roughly rectangular. It has multiple venting grooves 1022 at the bottom, and multiple positioning protrusions 1021 are also provided on the bottom of the upper plastic 102. The positive electrode assembly 10 includes a positive upper electrode post 101 and a positive lower electrode post 104; the negative electrode assembly 20 includes a negative upper electrode post 201 and a negative lower electrode post 204. The positive sealing ring 103 and the negative sealing ring 203 have the same structure, as do the positive upper plastic 102 and the negative upper plastic 202, and the positive electrode assembly 10 and the negative electrode assembly 20. For ease of description, only the structures of the positive electrode assembly 10, the positive sealing ring 103, and the positive upper plastic 102 will be described in detail below; the structures of the negative electrode assembly 20, the negative sealing ring 203, and the negative upper plastic 202 will not be described in detail. Figure 6 As shown, the positive electrode sealing ring 103 of this utility model has a hollow cylindrical structure. In the vertical direction, it presents a T-shaped structure, wider at the top and narrower at the bottom. It can be made of materials with good insulation and sealing properties, such as fluororubber and PP. The positive electrode sealing ring 103 includes a main body 1031 and a flange 1032 extending radially outward from the main body 1031. The diameter of the flange 1032 is larger than the diameter of the main body 1031 by 0.4mm to 5mm, preferably 3mm.

[0023] The diameter of the flange 1032 is preferably 6 cm. The positive electrode upper electrode post 101 is constructed as follows: Figure 7The columnar structure shown includes an upper end 1011, a middle part 1012, and a lower end 1013. The cross-sectional area of ​​the upper end 1011 is larger than that of the middle part 1012, and the cross-sectional area of ​​the middle part 1012 is larger than that of the lower end 1013. Thus, the positive electrode upper electrode post 101 is formed into a double-step columnar structure. The diameter of the lower end 1013 is preferably 4cm to 18cm, and the diameter of the middle part 1012 is 0.2mm to 15mm larger than that of the lower end. The lower plastic 40 is made of insulating material and is configured to be connected to the top cover plate 30. The connection method with the top cover plate 30 can be welding or snap-fit ​​connection. The connection method between the top cover plate 30 and the upper plastic 40 is not limited. The lower plastic 40 includes a first through hole 401 and a second through hole 402. At least a portion of the positive electrode upper electrode post 101 can pass through the first through hole 401, and at least a portion of the negative electrode upper electrode post 201 can pass through the second through hole 402.

[0024] The secondary battery top cover of this utility model is assembled according to the following steps: First, the upper plastic 102 is installed in the limiting groove 303 on the top cover plate 30, and the positioning protrusion 1021 on the upper plastic 102 matches the corresponding positioning recess in the limiting groove 303, so that the upper plastic 102 can be stably and quickly installed in the limiting groove 303 and is not easy to shift, and the upper plastic 102 can be stably located in the top cover plate 30; then the sealing ring 103 is installed in the first electrode through hole 301.

[0025] During installation, the main body 1031 passes through the first electrode through hole 301, and the flange 1032 abuts against the top cover plate 30. Then, the positive upper electrode 101 passes through the first electrode through hole 301 and the lower plastic 40. Finally, the positive lower electrode 104 is connected to the lower end 1013 of the positive upper electrode 101 by welding. During the installation of the electrode assembly, the upper end 1011 of the positive upper electrode 101 abuts against the limiting groove 303 of the top cover plate 30, and the middle part 1012 passes through the first electrode through hole 301 on the top cover plate and is inserted into the main body 1031 and flange 1032 of the sealing ring 103, so that the lower end 1013 extends out of the lower plastic 40. Then, the lower end 1013 extends into the positive lower electrode 104. A welded part 60 is formed at the connection between the upper positive electrode post 101 and the lower positive electrode post 104 by welding, thereby connecting the upper positive electrode post 101 and the lower positive electrode post 104.

[0026] They are connected to form a pole post assembly 10. The structure of the secondary top cover after assembly is as follows: Figure 5As shown. The flange portion 1032 of the sealing ring 103 is located between the positive electrode upper post 101 and the top cover plate 30 to form a first sealing portion for sealing the gap between the positive electrode upper post 101 and the top cover plate 30; the main body portion 1031 of the sealing ring 103 is located outside the middle portion 1012 of the positive electrode upper post to seal the gap between the middle portion 1012 of the positive electrode upper post and the top cover plate 30 to form a second sealing portion; at the same time, in this embodiment, the lower end portion 1013 of the positive electrode upper post and the lower positive electrode post 104 are welded together to form a weld portion 60 to constitute a fourth sealing portion.

[0027] The welding part 60 of the secondary battery top cover of this utility model is formed into a circle, and the diameter of the welding part is equal to the diameter of the lower end of the positive electrode upper post 1013. In this embodiment, the diameter of the lower end of the positive electrode upper post is 4cm~18cm. Compared with the prior art, the welding part is the middle part of the upper post with a larger diameter. The welding part of the secondary battery top cover of this utility model has a smaller diameter and fewer parts that need to be welded. Therefore, it is not easy to have the risk of welding failure. It can significantly improve the welding stability between the positive electrode upper post 101 and the positive electrode lower post 104, as well as the airtightness of the connection between the positive electrode upper post and the positive and negative posts. It will not cause the phenomenon of poor sealing performance between the upper and lower posts due to the excessive welding area of ​​the upper and lower posts in the prior art. In this embodiment, the upper and lower terminals of the positive terminal assembly can be made of the same metal material, such as aluminum. However, the upper and lower terminals of the negative terminal assembly are made of different metal materials, such as aluminum for the upper terminal and copper for the lower terminal, which reduces the production cost of the negative terminal assembly.

[0028] Meanwhile, the sealing ring 103 of the secondary battery top cover of this utility model includes a main body 1031 and a flange 132 protruding radially outward from the main body. That is, the diameter of the flange 1032 is larger than the diameter of the main body 1031, and the flange 1032 is located between the upper electrode post 101 and the top cover plate 30, used to seal the gap between the upper electrode post 104 and the top cover plate 30. Since the diameter of the flange 1032 is larger than that of the main body 1031, the flange 1032 can further fill the gap between the upper end 1011 of the upper electrode post and the top cover plate 30 that cannot be filled by the upper plastic 102. This can prevent the upper plastic 102 from failing to fill the top cover plate and the top of the upper electrode post near the positive electrode post through hole 301, thus preventing creepage and improving the safety performance of the battery top cover. Compared with conventional sealing rings without flanges, the flange 1032... This design prevents electrolyte from leaking out through the gap between the lower plastic and the lower electrode post. Additionally, the bottom of the upper plastic section of this invention features a venting groove. This venting groove prevents poor sealing caused by false airtightness during helium testing, improving the airtightness safety of the battery cell and enhancing the safety performance of the battery top cover.

[0029] Meanwhile, the positive electrode upper pole of the secondary battery top cover of this utility model is composed of a two-layer stepped columnar structure, with the cross-sectional area of ​​the pole decreasing from top to bottom. The upper pole can be easily formed by a simple stamping process, improving the efficiency of the stamping process and reducing the production cost of the upper pole. Moreover, the large cross-sectional area at the upper end can increase the contact area between the upper plastic and the top cover plate, improve the insulation and sealing of the upper plastic, and improve the performance of the battery cell. The cross-sectional area of ​​the middle part is smaller than that at the upper end but larger than that at the lower end; the small cross-sectional area of ​​the middle part can reduce the overall mass of the upper pole. At the same time, in order to further reduce the mass of the pole, the diameter of the lower end that extends through the top cover plate into the lower plastic and protrudes out is minimized, which can further reduce the mass of the pole. At the same time, the reduced diameter of the lower end makes the welding part between the upper and lower poles smaller, improving welding stability and avoiding local welding defects caused by excessive welding area. In this embodiment, the upper end of the upper pole is a cuboid, and the middle and lower ends are cylindrical.

[0030] Optionally, when the battery shape changes, the upper end of the upper electrode post can also be set to a cylindrical shape, and the middle and lower ends can also be cylindrical.

[0031] In summary, the secondary battery top cover of this utility model has a flange at the upper end of the sealing ring, which can prevent creepage between the upper electrode post and the top cover plate, thereby improving the safety performance of the battery top cover. At the same time, the upper electrode post assembly of this utility model is set as a stepped structure from top to bottom, thereby reducing the overall weight of the electrode post and thus the battery top cover.

Claims

1. A battery top cover, comprising: The top cover plate is provided with a first pole post through hole and a second pole post through hole; The lower plastic sheet is provided with a first through hole and a second through hole, and the lower plastic sheet is configured to be connected to the top cover plate; The electrode assembly includes an upper electrode and a lower electrode; the upper electrode passes through the first electrode through-hole and the first through-hole. The upper electrode and the lower electrode are connected by welding. A plastic layer is placed between the top cover plate and the upper electrode post to insulate and separate the upper electrode post from the top cover plate; The feature is that it further includes a sealing ring, the sealing ring including a main body and a flange extending radially outward from the main body, the flange being located in the gap between the upper pole and the top cover plate in the vertical direction, the main body passing through the first pole through hole and the first through hole and located outside the upper pole to seal the gap between the lower plastic and the upper pole.

2. The battery top cover as described in claim 1, characterized in that, The upper pole post includes an upper end, a middle part, and a lower end, wherein the cross-sectional area of ​​the upper end is larger than the cross-sectional area of ​​the middle part, and the cross-sectional area of ​​the middle part is larger than the area of ​​the lower end.

3. The battery top cover as described in claim 2, characterized in that, The sealing ring is made of fluororubber.

4. The battery top cover as described in claim 2, characterized in that, The upper part is a cuboid, and the middle part and the lower part are cylindrical.

5. The battery top cover as described in claim 2, characterized in that, The upper end is cylindrical.

6. The battery top cover as described in claim 2, characterized in that, The lower electrode post and the lower end of the upper electrode post are connected by welding.

7. The battery top cover as described in claim 3, characterized in that, The bottom of the upper plastic is also provided with an air vent.

8. The battery top cover as described in claim 3, characterized in that, The upper electrode and the lower electrode are made of different metallic materials.

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