Top cover assembly, assembling method thereof and battery cell

Abstract

The invention relates to a cylindrical battery top cover assembly and an assembling method thereof, and a battery cell comprising the top cover assembly. The top cover assembly comprises a T-shaped pole terminal, an upper plastic part, a top cover sheet, an inclined plane sealing ring, a lower plastic part, a compression ring and a confluence disc, the disc part provides a wide welding surface, the cylinder is used for connecting the compression ring and the confluence disc, and the welding reliability and stability are enhanced. And the compression ring and the confluence plate are sleeved on the cylinder of the pole terminal and are firmly connected with the pole terminal in a laser welding manner. The design of the inclined plane sealing ring enables the sealing ring to distribute stress more uniformly when the sealing ring is stressed, sealing failure is avoided, the assembly method comprises the steps of stacking the assemblies, applying pressure to the confluence plate to compress the sealing ring, and welding the compression ring, the confluence plate and the pole terminal in the state that the sealing ring is compressed, so that efficient and stable connection among the assemblies is realized, and the assembly efficiency is improved. Therefore, the sealing performance, the electrical connection reliability and the long-term stability of the battery are improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a top cover assembly, an assembly method thereof, and a battery cell. Background Art

[0002] In the field of battery technology, cylindrical batteries are an important energy storage device and are widely used in various portable electronic devices and electric vehicles. As an important component of the battery, the cover assembly of the cylindrical battery must not only have good sealing performance, but also ensure the stability of the internal structure of the battery and the reliability of the electrical connection. However, the traditional cylindrical battery cover structure has a series of problems in design that need to be solved.

[0003] At present, the cylindrical battery cover structure is usually composed of multiple components such as terminals, upper plastic (upper insulation), sealing rings, top cover sheets, lower plastic, riveted poles and busbars. This complex multi-component structure not only increases the manufacturing cost, but also significantly increases the difficulty of assembly, which is not conducive to improving production efficiency. In addition, the assembly accuracy requirements between the components are extremely high. Once an assembly error occurs, it is very easy to cause the battery sealing performance to decline or the electrical connection to be poor, thereby affecting the overall performance and safety of the battery.

[0004] Regarding the connection method of the cover assembly, although the traditional riveting method has achieved the fixation between the components to a certain extent, the rivet structure used in the middle of the riveted terminal limits the customer's welding needs. Since the rivet part is a non-weldable area, the welding area of ​​the terminal is reduced, which in turn affects the stability of the electrical connection between the battery and the external circuit. At the same time, the amount of expansion generated during the riveting process is difficult to accurately control, which can easily lead to the problem of terminal falling off, posing a potential risk to the safe use of the battery. Even more serious is the problem of the gap between the lower plastic and the sealing ring. Due to the tiny gap between the two, not only will it cause weak conduction between the cover and the pole, but the sealing ring may also expand and squeeze out when squeezed, thereby squeezing and lifting the lower plastic, seriously affecting the sealing performance and service life of the battery.

[0005] In summary, although the current cylindrical battery cover structure still has many shortcomings in terms of cost, assembly efficiency, electrical connection stability and sealing performance, a new top cover assembly and assembly method thereof are needed to simplify the cover structure, improve assembly efficiency, and enhance electrical connection stability and sealing performance. Summary of the invention

[0006] The purpose of the present application is to provide a top cover assembly, which can improve the reliability of the cover plate, increase the terminal welding area, and improve the customer's welding utilization rate; eliminate the terminal welding surface rivets, increase the welding area, and optimize the plastic shape to ensure the insulation reliability of the cover plate. The top cover assembly of the present application includes a pole terminal, an upper plastic part, a top cover sheet, a sealing ring, a lower plastic part, a pressure ring and a busbar; The pressure ring and the busbar are sleeved on the pole terminal, and the pressure ring is arranged between the sealing ring and the busbar; The surface of the sealing ring in contact with the lower plastic part is an inclined surface; The pressure ring, the busbar and the pole terminal are welded together, and the sealing ring is in a squeezed state.

[0007] In one embodiment, the pole terminal is a T-shaped terminal, including a disc portion and a circular cylinder, wherein the disc portion is provided at one end of the circular cylinder, and the other end is used to connect the pressure ring and the busbar.

[0008] In one of the embodiments, the pressure ring and the busbar are sleeved on the circular cylinder, and the pressure ring and the busbar are welded at the joint with the pole terminal.

[0009] In one embodiment, the surface of the disc portion is a flat surface.

[0010] In one of the embodiments, the top cover sheet has a concave-convex structure matching the upper plastic part and the sealing ring.

[0011] In one of the embodiments, a protective layer is further included, wherein the protective layer is formed on the back side of the top cover assembly and covers the lower plastic part and the busbar.

[0012] The present application further provides a method for assembling a top cover assembly, comprising: Stack the pole terminal, upper plastic part, top cover sheet, sealing ring, pressing ring, lower plastic part and busbar in sequence; Applying pressure to the busbar to compress the sealing ring; The sealing ring is in a compressed state, and the pressure ring, the busbar and the pole terminal are welded; Wherein, the surface where the sealing ring contacts the lower plastic part is an inclined surface.

[0013] In one of the embodiments, the method further includes processing the surface of the T-shaped terminal and using it as a terminal welding surface.

[0014] In one embodiment, the pressure ring, the busbar and the pole terminal are welded by a laser welding method.

[0015] In addition, the present application further provides a battery cell, comprising the aforementioned top cover assembly.

[0016] Compared with the prior art, this application has the following beneficial effects: This application adopts a T-shaped pole terminal so that the entire terminal surface is a weldable area. Compared with the traditional structure in which the middle of the terminal contains a non-weldable rivet part, the terminal design of this application greatly increases the welding area, thereby improving the customer's welding flexibility and utilization. The T-shaped terminal includes a disc part and a circular cylinder. The disc part serves as an extension of the welding surface to ensure the reliability and stability of the welding. This design not only meets the customer's demand for welding area, but also optimizes the welding process and improves the overall performance of the battery.

[0017] The present application designs the surface where the sealing ring contacts the lower plastic part as an inclined surface. This innovative design ensures that the sealing ring can fill the vacant area around the center hole of the lower plastic part after expansion, effectively avoiding the problem of warping of the lower plastic part due to the expansion and squeezing of the sealing ring, while ensuring the tight fit of the sealing ring and enhancing the sealing performance of the battery. The inclined surface design enables the sealing ring to evenly distribute stress when under pressure, avoiding the problem of weak connection caused by gaps in traditional structures, thereby improving the waterproof and dustproof levels of the battery and extending the battery life.

[0018] The present application realizes the extrusion seal of the sealing ring through the pressure ring designed on the inner side, and fixes the lower plastic part at the same time, eliminating the traditional riveting process. When the sealing ring is compressed, the extrusion seal of the sealing ring and the welding and fixing of the busbar can be completed simultaneously through a laser welding process, which simplifies the assembly process, saves work steps and improves production efficiency. The introduction of the pressure ring not only simplifies the assembly process, but also realizes high-precision welding and fixing through laser welding technology, ensuring the structural stability of the top cover assembly and the reliability of the electrical connection. In addition, this design also reduces the number of components, reduces manufacturing costs, and improves the overall cost performance of the battery. In summary, the top cover assembly, its assembly method and battery cell technical solution provided in this application show beneficial effects in improving the terminal welding area and utilization rate, optimizing the coordination between the sealing ring and the lower plastic part, and simplifying the assembly process. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of a top cover assembly in an embodiment of the present application; Figure 2 is a schematic diagram of the cross-sectional structure of a top cover assembly in one embodiment of the present application; Figure 3 It is a flow chart of the assembly method of the top cover assembly of the present application.

[0020] Explanation of reference numerals: 100, pole terminal; 200, upper plastic part; 300, top cover plate; 400, sealing ring; 500, lower plastic part; 600, pressure ring; 700, busbar. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. It is to be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some structures related to the present application are shown in the accompanying drawings, rather than all structures. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0022] The terms "including" and "having" and any variations thereof in this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0023] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0024] As a key component of cylindrical batteries, the top cover assembly is not only responsible for the sealing task inside the battery, but also for the reliability and safety of the electrical connection. The traditional top cover assembly design has many shortcomings, such as a large number of cover components, complex assembly, limited terminal welding area, and easy gaps between the sealing ring and the lower plastic part. These problems not only affect the production efficiency and cost of the battery, but may also pose a potential threat to the performance and safety of the battery. In order to solve the above problems, the present application proposes a new top cover assembly design, as well as its unique assembly method and battery cell structure. The top cover assembly optimizes the component structure, simplifies the assembly process, and improves the terminal welding area and sealing performance, thereby improving battery performance and reducing production costs. On this basis, the present invention further provides a battery cell, which adopts a top cover assembly, thereby improving production efficiency and reducing manufacturing costs while ensuring battery performance and safety. Please refer to Figure 1 to Figure 2As shown, it is a structural schematic diagram of a top cover assembly in an embodiment of the present application, wherein the top cover assembly includes a pole terminal 100, an upper plastic part 200, a top cover sheet 300, a sealing ring 400, a lower plastic part 500, a pressure ring 600 and a busbar 700, wherein the pressure ring 600 and the busbar 700 are sleeved on the pole terminal 100, the pressure ring 600 is arranged between the sealing ring 400 and the busbar 700, and the surface where the sealing ring 400 contacts the lower plastic part 500 is an inclined surface, wherein the pressure ring 600, the busbar 700 and the pole terminal 100 are welded together by welding, and the sealing ring 400 is in an extruded state.

[0025] As a key component of cylindrical batteries, the rationality of the structural design of the top cover assembly directly affects the overall performance and safety of the battery. The top cover assembly of the present application integrates multiple elements such as the pole terminal 100, the upper plastic part 200, the top cover sheet 300, the sealing ring 400, the lower plastic part 500, the pressure ring 600 and the busbar 700 to achieve efficient and stable connection between components. Specifically, the pole terminal 100, as the connection point between the battery and the external circuit, undertakes the important task of current transmission. The pole terminal 100 is designed to include a structure including a pressure ring 600 and a busbar 700, wherein the pressure ring 600 is arranged between the sealing ring 400 and the busbar 700, which not only ensures a close fit between the components, but also improves the convenience and stability of assembly. The sealing ring 400 of the present application adopts a bevel design, so that the surface in contact with the lower plastic part 500 presents a bevel. On the one hand, the bevel design enables the sealing ring 400 to distribute stress more evenly when subjected to pressure, thereby avoiding the problem of sealing failure caused by stress concentration; on the other hand, the bevel design also ensures that the sealing ring 400 can fill the vacant area around the center hole of the lower plastic part 500 after expansion, thereby enhancing the sealing performance of the battery.

[0026] During the assembly process, the pressure ring 600, the busbar 700 and the pole terminal 100 are tightly connected together by welding. This welding process not only ensures the reliability of the electrical connection between the components, but also puts the sealing ring 400 in an extruded state through the heat generated by welding. The extruded sealing ring 400 further enhances the sealing effect between the components and ensures the stability and safety of the internal environment of the battery. The top cover assembly of the present application achieves efficient and stable connection between components through structural design and clever component arrangement. Among them, the introduction of the bevel sealing ring 400 design and the pressure ring 600 improves the sealing performance of the battery and enhances the connection stability and electrical connection reliability between the components. These designs together constitute the core technical advantages of the top cover assembly, providing strong support for the performance improvement and safety assurance of cylindrical batteries.

[0027] Specifically, the pole terminal 100 is a T-shaped terminal, including a disc portion and a circular cylinder. The disc portion is provided at one end of the circular cylinder, and the other end is used to connect the pressure ring 600 and the busbar 700. The T-shaped terminal is composed of a disc portion and a circular cylinder, which constitute the main structure of the pole terminal 100. The disc portion, as the upper end of the T-shaped terminal, provides a wide and flat welding surface, greatly increasing the weldable area of ​​the terminal surface. Compared with the traditional design in which the middle of the terminal contains a non-weldable rivet portion, the T-shaped terminal of the present application provides more flexible and diverse welding options, thereby improving the reliability and stability of welding.

[0028] The circular cylinder serves as the lower end of the T-shaped terminal and is used to connect with the pressure ring 600 and the busbar 700. One end of the circular cylinder is tightly connected to the disc portion, and the other end is reserved for a connection interface with the pressure ring 600 and the busbar 700, ensuring a close fit between the components and greatly improving the convenience and stability of assembly. During the assembly process, the pressure ring 600 and the busbar 700 can be easily sleeved on the circular cylinder and formed into a firm connection with the pole terminal 100 by welding. The design of the T-shaped terminal also fully considers the internal spatial layout and electrical connection requirements of the battery. The presence of the disc portion not only facilitates welding, but also avoids the stress concentration problem caused by welding, thereby extending the service life of the battery. The design of the circular cylinder ensures the smooth connection between the pole terminal 100 and other components inside the battery, providing a stable channel for the transmission of current.

[0029] Specifically, the pressure ring 600 and the busbar 700 are sleeved on the circular cylinder, and the pressure ring 600 and the busbar 700 are welded at the junction with the pole terminal 100. This design simplifies the assembly process and improves the connection strength and electrical connection reliability between components. During the assembly process, the pressure ring 600 is first sleeved on the circular cylinder and located between the sealing ring 400 and the busbar 700, ensuring that the pressure ring 600 can effectively squeeze the sealing ring 400 during the welding process, thereby achieving a tight fit of the sealing ring 400 and the sealing performance of the battery. The busbar 700 is also sleeved on the circular cylinder and in close contact with the pressure ring 600 and the pole terminal 100. During the welding process, heat sources such as laser beams or arcs are accurately guided to the junction of the pressure ring 600, the busbar 700 and the pole terminal 100, and a firm connection between the components is achieved by melting the metal. This set of welding design simplifies the assembly process and reduces the connection steps between components, thereby improving production efficiency. The welding connection has high strength and electrical connection reliability, which can ensure that the battery can maintain a stable working state in harsh environments. In addition, the introduction of the pressure ring 600 also enhances the sealing effect of the sealing ring 400, further improving the waterproof, dustproof level and safety of the battery. By precisely controlling the welding parameters and heat source distribution, the present application effectively reduces the thermal stress and deformation generated during the welding process, thereby ensuring the connection quality between components and the long-term stability of the battery.

[0030] Specifically, the surface of the disc portion is a flat surface. The flat surface of the disc portion first provides great convenience for welding operations. When the battery is in use, the disc portion needs to be welded and connected with an external circuit or other battery components. The flat surface can ensure the uniform distribution of solder or solder during welding, avoid the occurrence of poor welding or cold welding, and thus improve the reliability and stability of welding. The flat surface of the disc portion also helps to improve the overall aesthetics of the battery. After the battery is assembled, the disc portion is often exposed as part of the battery appearance. The flat and smooth surface can reduce the appearance of defects such as scratches and dents. In addition, the flat surface of the disc portion also helps to improve the heat dissipation performance of the battery. During the operation of the battery, a certain amount of heat will be generated. The flat surface of the disc portion can more effectively conduct the heat to the external environment, thereby reducing the temperature inside the battery and improving the working efficiency and safety of the battery. By selecting high-strength, corrosion-resistant materials and combining precise processing technology, the present invention ensures that the disc portion has sufficient strength and corrosion resistance while maintaining flatness to meet the use requirements of the battery in various harsh environments.

[0031] Specifically, the top cover sheet 300 has a concave-convex structure that matches the upper plastic part 200 and the sealing ring 400. The concave-convex structure on the top cover sheet 300 and the upper plastic part 200 are tightly fitted. This design effectively increases the contact area between the two, thereby improving the stability and reliability of the connection. During the operation of the battery, even if subjected to external forces such as vibration or impact, the connection between the top cover sheet 300 and the upper plastic part 200 can remain stable, avoiding performance degradation or safety hazards caused by looseness. Secondly, the matching design of the concave-convex structure and the sealing ring 400 further improves the sealing performance of the battery. As an important part of the battery sealing system, the performance of the sealing ring 400 directly affects the waterproof, dustproof and explosion-proof capabilities of the battery. By designing a concave-convex structure for the top cover sheet 300, the sealing ring 400 can be more closely fitted between the top cover sheet 300 and the battery housing, effectively blocking the intrusion of external moisture, dust and gas, thereby ensuring the stable operation of the battery in harsh environments. While pursuing the aesthetics and practicality of the concave-convex structure of the top cover sheet 300, the processing cost and production efficiency are fully considered. By adopting advanced mold design and manufacturing technology, the present invention ensures the processing accuracy and consistency of the concave-convex structure of the top cover sheet 300, thereby reducing production costs and improving production efficiency. In summary, the present application achieves a significant improvement in connection stability and sealing performance by designing a concave-convex structure for the top cover sheet 300 that perfectly matches the upper plastic part 200 and the sealing ring 400.

[0032] Specifically, it also includes a protective layer, which is formed on the back of the top cover assembly, covering the lower plastic part 500 and the busbar 700. The protective layer effectively enhances the weather resistance and durability of the top cover assembly. During the use of the battery, the top cover assembly may be eroded by various environmental factors (such as humidity, temperature, ultraviolet rays, etc.), as well as collisions or scratches by external objects. The protective layer, as a solid barrier, can resist these adverse factors, extend the service life of the top cover assembly, and ensure the stable operation of the battery. The presence of the protective layer provides an additional insulating layer for the busbar 700, effectively preventing safety hazards caused by current leakage or short circuit. In addition, the design of the protective layer can also take into account the heat dissipation performance of the battery. During the operation of the battery, a certain amount of heat will be generated. The protective layer can be made of materials with good thermal conductivity, which can effectively conduct heat from the inside of the top cover assembly to the external environment, thereby reducing the temperature inside the battery and improving the working efficiency of the battery.

[0033] The present application further provides an assembly method of a top cover assembly, comprising: stacking a pole terminal 100, an upper plastic part 200, a top cover sheet 300, a sealing ring 400, a pressure ring 600, a lower plastic part 500 and a busbar 700 in sequence, applying pressure to the busbar 700 to compress the sealing ring 400, and welding the pressure ring 600, the busbar 700 and the pole terminal 100 while the sealing ring 400 is in a compressed state, wherein the surface of the sealing ring 400 in contact with the lower plastic part 500 is an inclined surface. First, the pole terminal 100, the upper plastic part 200, the top cover sheet 300, the sealing ring 400, the pressure ring 600, the lower plastic part 500 and the busbar 700 are stacked in a specific order. This step ensures the accurate positioning of each component during the assembly process. Then, pressure is applied to the busbar 700 to compress the sealing ring 400. This step is the key in the assembly process to ensure that the sealing ring 400 can play a good sealing role in the subsequent welding process. By applying appropriate pressure, the sealing ring 400 is evenly compressed between the pressure ring 600, the busbar 700 and the pole terminal 100 to form a barrier. When the sealing ring 400 is compressed, the pressure ring 600, the busbar 700 and the pole terminal 100 are welded. This step realizes a firm connection between the components and ensures the stable operation of the battery in harsh environments. Since the sealing ring 400 is in a compressed state during the welding process, after the welding is completed, the sealing ring 400 can continue to maintain its sealing performance and provide long-term protection for the battery. The surface of the sealing ring 400 in the present application that contacts the lower plastic part 500 is designed as an inclined surface, so that the sealing ring 400 can deform more evenly when subjected to pressure, thereby improving the sealing effect of the sealing ring 400. The inclined surface design also helps to increase the contact area between the sealing ring 400 and the lower plastic part 500, further enhancing the connection stability between the components. In addition, the inclined surface design also facilitates the adjustment of the position of the sealing ring 400 during the assembly process, ensuring that the sealing ring 400 can be accurately installed in the predetermined position.

[0034] Specifically, it also includes surface treatment of the T-shaped terminal, which serves as the terminal welding surface. By surface treatment of the T-shaped terminal, the quality of its welding surface is improved. The surface treatment process can remove oxides, oil stains and other impurities on the terminal surface, making the welding surface purer and smoother, thereby improving the reliability and stability of welding. During the welding process, the pure welding surface can ensure that the solder or solder forms a good metallurgical bond with the terminal surface, avoiding the occurrence of problems such as poor welding and cold welding. Secondly, the surface treatment can also enhance the corrosion resistance of the T-shaped terminal. During the use of the battery, the terminal surface may be corroded by corrosive substances such as moisture and salt spray, resulting in terminal performance degradation or failure. By surface treatment of the terminal, such as tin plating, galvanizing, etc., a protective film can be formed on the terminal surface to effectively block the invasion of corrosive substances, thereby extending the service life of the terminal.

[0035] Specifically, the pressure ring 600, the busbar 700 and the pole terminal 100 are welded by a laser welding method. The laser welding method ensures the stability and reliability of the welding process with its high precision and high speed. The laser beam can be focused on the welding part to achieve rapid heating and melting of a small area, thereby ensuring a good combination between the pressure ring 600, the busbar 700 and the pole terminal 100, so that the welding joint has high strength and good sealing, effectively avoiding the occurrence of problems such as poor welding and cold welding, and providing a strong guarantee for the stable operation of the battery. Secondly, the laser welding method also has good adaptability. In the assembly process of the cylindrical battery top cover assembly, due to the large differences in size, shape and material of each component, the traditional welding method is often difficult to achieve the ideal welding effect, while laser welding can flexibly adjust the laser parameters (such as power, wavelength, focusing distance, etc.) according to the characteristics of different components, so as to achieve precise welding of different materials, so that laser welding has a wide range of application prospects in the assembly process of the cylindrical battery top cover assembly.

[0036] In addition, the present application further provides a battery cell, including the aforementioned top cover assembly. The pole of the present application selects a T-shaped structure, and the terminal surface is entirely a weldable area. After the T-shaped terminal is assembled, the upper plastic and the sealing ring 400 are assembled in the same form as the original structure, and the middle circular surface of the lower plastic is designed as a bevel structure to ensure that the cover plate and the pressure ring 600 and the busbar 700 are completely insulated. At the same time, the sealing ring 400 can be filled along the bevel after being squeezed and expanded, and further insulated. At the same time, the bevel structure prevents the sealing ring 400 from expanding and squeezing the plastic outward, causing the lower plastic to deform and warp; after the pressure ring 600, the busbar 700 and the pole are assembled, laser welding is performed, and the pressure ring 600 ensures that the sealing ring 400 is squeezed and sealed and fixed to the lower plastic, and the busbar 700 is welded for electrical connection.

[0037] As can be seen from the foregoing, the present application provides an optimized cylindrical battery top cover assembly and an assembly method thereof, as well as a battery cell including the top cover assembly. The top cover assembly includes a pole terminal (specifically a T-shaped terminal), an upper plastic part, a top cover sheet, a sealing ring, a lower plastic part, a pressure ring and a busbar. The T-shaped terminal includes a disc portion and a circular cylinder. The disc portion provides a wide welding surface, and the circular cylinder is used to connect the pressure ring and the busbar. This design enhances the reliability and stability of welding, while improving the space utilization and electrical connection efficiency inside the battery. In the assembly, the pressure ring and the busbar are sleeved on the circular cylinder of the pole terminal and are firmly connected to the pole terminal by welding. In particular, the surface where the sealing ring contacts the lower plastic part is designed to be an inclined surface, which not only allows the sealing ring to distribute stress more evenly when under pressure to avoid sealing failure, but also ensures that the sealing ring can fill the vacant part around the center hole of the lower plastic part after expansion, thereby enhancing the sealing performance of the battery.

[0038] During the assembly process, laser welding is used to weld the pressure ring, busbar and pole terminal together. This high-precision, high-speed welding method ensures the stability and reliability of the welding process while improving production efficiency. In addition, the surface of the T-shaped terminal has been specially treated to improve the quality and corrosion resistance of the welding surface. In summary, the top cover assembly of the present application achieves efficient and stable connection between components through structural design and component arrangement, significantly improving the sealing performance, electrical connection reliability and long-term stability of the battery.

[0039] The above is only a specific implementation of the present application, and any other improvements made based on the concept of the present application are deemed to be within the protection scope of the present application.

Claims

1. A top cover assembly, characterized in that: It comprises a pole terminal (100), an upper plastic part (200), a top cover sheet (300), a sealing ring (400), a lower plastic part (500), a pressure ring (600) and a busbar (700); The pressure ring (600) and the busbar (700) are sleeved on the pole terminal (100), and the pressure ring (600) is arranged between the sealing ring (400) and the busbar (700); The surface where the sealing ring (400) contacts the lower plastic part (500) is an inclined surface; The pressure ring (600), the busbar (700) and the pole terminal (100) are welded together, and the sealing ring (400) is in a squeezed state.

2. The top cover assembly according to claim 1, characterized in that: The pole terminal (100) is a T-shaped terminal, comprising a disc portion and a circular cylinder; the disc portion is provided at one end of the circular cylinder, and the other end is used to connect the pressure ring (600) and the busbar (700).

3. The top cover assembly according to claim 2, characterized in that: The pressure ring (600) and the busbar (700) are sleeved on the circular column, and the pressure ring (600) and the busbar (700) are welded at the joint with the pole terminal (100).

4. The top cover assembly according to claim 2, characterized in that: The surface of the disc portion is a flat surface.

5. The top cover assembly according to claim 1, characterized in that: The top cover sheet (300) has a concave-convex structure matching the upper plastic part (200) and the sealing ring (400).

6. The top cover assembly according to claim 1, characterized in that: It also includes a protective layer, which is formed on the back of the top cover assembly and covers the lower plastic part (500) and the busbar (700).

7. A method for assembling a top cover assembly, characterized in that: include: Stacking the pole terminal (100), the upper plastic part (200), the top cover sheet (300), the sealing ring (400), the pressure ring (600), the lower plastic part (500) and the busbar (700) in sequence; Applying pressure to the busbar (700) so that the sealing ring (400) is compressed; The sealing ring (400) is in a compressed state, welding the pressure ring (600), the busbar (700) and the pole terminal (100); Wherein, the surface where the sealing ring (400) contacts the lower plastic part (500) is an inclined surface.

8. The method for assembling a top cover assembly according to claim 7, characterized in that: It also includes surface treatment of the T-shaped terminal, which serves as the terminal welding surface.

9. The method for assembling a top cover assembly according to claim 7, characterized in that: The pressure ring (600), the busbar (700) and the pole terminal (100) are welded using a laser welding method.

10. A battery cell, characterized in that: A top cover assembly comprising any one of claims 1-6.

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