Cover plate assembly for high-magnification application and cylindrical battery

Abstract

The utility model discloses a cover plate assembly for high magnification application and a cylindrical battery, the cover plate assembly comprises a pole, the pole is sleeved with a confluence plate, and the confluence plate comprises a current collecting area and a welding area. A lower plastic cover is arranged at the upper end of the confluence plate, a sealing element is connected to the upper end of the lower plastic cover, a top cover is sleeved on the sealing element, an assembly hole is formed in the middle of the top cover, and the pole penetrates out of the assembly hole; an upper plastic cover is embedded in the assembly hole, and a terminal is arranged at the upper end of the upper plastic cover and clamped on the pole. Through optimal design of the injection molding structure and the confluence disc structure and size, the contact area between assemblies is increased, the mechanical strength of the pole is improved, and the contact internal resistance is reduced, so that the overcurrent capacity of the structural member is remarkably improved. In addition, the end part of the confluence plate adopts a trapezoidal clearance design, so that the clearance space is utilized to the greatest extent, the safety of the battery cell and the electrolyte infiltration capacity are improved, the design is compatible with the existing preparation process, the operability is strong, and the mechanical strength of the pole and the performance of the battery cover plate are improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of battery cover plates, and in particular relates to a cover plate assembly and a cylindrical battery for high-rate applications. Background Art

[0002] Lithium-ion batteries are widely used in laptops, camcorders, digital cameras, and other mobile communication devices. They come in a wide variety of sizes, are widely used, and are in high demand. As living standards improve, people are demanding higher and higher rates of lithium-ion batteries, especially power batteries.

[0003] For example, cylindrical lithium-ion batteries with a liquid injection port located in the center of the cover assembly are already available on the market. However, the complex connection method between the various parts of the cover assembly leads to a complex structure. Typically, riveting is used to achieve a mechanical fit between the pole and the terminal. However, due to the uneven contact interface, gaps are prone to occur, resulting in increased contact resistance and the risk of leakage.

[0004] Moreover, the battery covers on the market have large thickness, poor sealing at the cover joints, thin and narrow busbar design, and small surface area under the poles. When they are energized for a long time or when large currents pass through, the large internal resistance causes serious heat generation, resulting in a significant temperature rise in the battery, affecting the power output of the battery cells and easily causing excessive heat generation at the contact end, posing a potential safety risk.

[0005] Among the battery products on the market, there is no air-avoidance design at the corresponding positions of the busbar and the top cover explosion-proof valve, or even if there is an air-avoidance design, the area is insufficient, which is not conducive to timely ejection from the explosion-proof valve under extreme conditions of thermal runaway of the battery cell.

[0006] Therefore, in response to the above problems, it is urgent to design a cover assembly for high-rate applications to solve the safety hazards caused by rapid heat rise in the battery and the cover body when overcurrent occurs during battery use, thereby improving the safety of the battery and the cover and the battery's working performance. Utility Model Content

[0007] The purpose of this utility model is to provide a cover plate assembly and cylindrical battery for high-rate applications to solve the problems raised in the above background technology. The following technical solution is provided: a cover plate assembly and cylindrical battery for high-rate applications, wherein the cover plate assembly includes:

[0008] The pole is fitted with a busbar mounted on top, which includes a current collecting area and a welding area. A lower plastic cover is mounted on the top of the busbar, with a seal attached to its upper end. A top cover is mounted on the seal, with an assembly hole in the middle of the top cover, through which the pole extends. An upper plastic cover is mounted in the assembly hole, with a terminal mounted on its upper end, which is clipped onto the pole. The pole comprises a bottom plate, one end of which is provided with a boss for limiting position, and a columnar body with a limiter at its distal end.

[0009] In this technical solution, the lower and upper plastic covers of the injection-molded insulation are designed with right angles on their sides, which can improve injection volume and the yield rate of the injection and demolding process. A knurled design is also featured on the stopper to increase the injection contact surface. Compared with traditional riveting processes, this significantly reduces contact resistance and improves injection strength.

[0010] In addition, the diameter of the column part on the lower surface of the pole is in the range of 18-25mm to increase the contact area with the busbar, reduce internal resistance and improve the flow capacity.

[0011] In any of the above technical solutions, the current collecting plate further includes a current collecting area and a welding area. A through-hole is provided on one side of the current collecting area, and the current collecting plate is bonded to the bottom plate portion through the through-hole. The lower plastic cover is annular, and the middle portion of the columnar portion passes through the lower plastic cover, with the lower end of the lower plastic cover always tightly bonded to the end surface of the stopper portion. The top cover and the lower plastic cover are snap-fitted together, and a seal is sealed between the top cover and the lower plastic cover.

[0012] In this technical solution, the busbar adopts a widened and thickened design, which greatly improves the flow capacity during operation, thereby effectively preventing excessive temperature rise during large current charging and discharging. The width of the transition zone of the busbar can range from 25-35mm, and the overall thickness of the busbar can range from 0.5-1mm. In order to ensure weldability, the thickness of the collecting area and the welding area is thinned by 0.1-0.5mm. The end has a trapezoidal air-avoidance design to maximize the directional ejection of thermal runaway and increase the electrolyte infiltration capacity. By setting a seal, the electrolyte in the battery can be prevented from flowing out of one side of the cover plate, further isolating the electrolyte from the outside world, improving the mechanical reliability and airtightness of the structural parts, and increasing the service life of the battery.

[0013] By optimizing the injection molding structure and busbar dimensions, the contact area between components is increased, thereby improving the mechanical strength of the pole, reducing the internal contact resistance, and significantly enhancing the current capacity of the battery cover. The column battery cell current capacity is above 10C, and the temperature rise is less than 15°C under a 10C discharge rate test at room temperature.

[0014] The beneficial effects of this utility model are as follows: by optimizing the injection molding structure and the structure and dimensions of the busbar, the utility model can increase the contact area between components, improve the mechanical strength of the pole, and reduce the internal contact resistance, thereby significantly improving the current carrying capacity of the structural components. In addition, the end of the busbar adopts a trapezoidal air-avoidance design to maximize the use of the air-avoidance space, improve the safety of the battery cell and the electrolyte infiltration ability. The design of the busbar and the lower plastic cover is compatible with existing manufacturing processes and has strong operability. Without increasing the manufacturing cost of the cover, the mechanical strength of the pole and the performance of the battery cover are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is an exploded view of the battery cover in the present utility model;

[0016] Figure 2 It is a three-dimensional schematic diagram of the pole in the utility model;

[0017] Figure 3 It is a three-dimensional schematic diagram of the upper plastic cover in the utility model.

[0018] The reference numerals in the figure are: 10, pole; 11, bottom plate; 12, boss; 13, column; 14, limit portion; 20, top cover; 21, assembly hole; 30, seal; 40, busbar; 41, collecting area; 42, welding area; 50, lower plastic cover; 60, upper plastic cover; 70, terminal, 80, explosion-proof valve. DETAILED DESCRIPTION

[0019] The following will be combined with the accompanying drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of this application.

[0020] In the description of this application, it should be noted that the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments according to this application. For ease of description, the dimensions of the various parts shown in the drawings are not drawn according to the actual proportional relationship. Technologies, methods and equipment known to ordinary technicians in the relevant fields may not be discussed in detail, but where appropriate, the technologies, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, so once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0021] Example 1:

[0022] like Figure 1 As shown, this embodiment provides a cover plate assembly for high-rate applications, including:

[0023] The pole 10 is fitted with a busbar 40 mounted on top. The busbar 40 includes a current collecting area 41 and a welding area 42. A lower plastic cover 50 is mounted on the top of the busbar 40. A seal 30 is connected to the top of the lower plastic cover 50. A top cover 20 is mounted on the seal 30. A mounting hole 21 is provided in the middle of the top cover 20, through which the pole 10 extends. An upper plastic cover 60 is mounted on the mounting hole 21. A terminal 70 is mounted on the top of the upper plastic cover 60 and is secured to the pole 10. The terminal 70 is also equipped with an explosion-proof valve 80. The pole 10 includes a bottom plate portion 11, a boss portion 12 for limiting is provided at one end of the bottom plate portion 11, a column portion 13 is provided at the other end of the bottom plate portion 11, and a limiting portion 14 is provided at the end of the column portion 13; one end of the terminal 70 is tightly fitted with the upper plastic cover 60, and the limiting portion 14 is riveted to the terminal 70 as a whole.

[0024] In this technical solution, the sides of the lower plastic cover 50 and upper plastic cover 60 of the injection-molded insulating component are designed at right angles, which can improve the injection volume and the yield rate of the injection and demolding process. The limiter 14 is provided with a knurling design to increase the injection contact surface. Compared with traditional riveting processes, this greatly reduces the contact internal resistance and improves the injection strength. In addition, one end surface of the upper plastic cover can be designed as a groove, and a bump can be provided on the groove to prevent the upper plastic cover 60 and terminal 70 from loosening during riveting installation, thereby preventing them from twisting.

[0025] In addition, the diameter of the column portion 13 on the lower surface of the pole is in the range of 18-25 mm, so as to increase the contact area with the busbar, reduce the internal resistance, and improve the current carrying capacity.

[0026] In a preferred embodiment of the present invention:

[0027] like Figure 1 As shown, the manifold 40 specifically includes a current collecting area 41 and a welding area 42. A through-hole is provided on one side of the current collecting area 41, and the manifold 40 is bonded to the bottom plate 11 through the through-hole. The lower plastic cover 50 is annular, with the middle portion of the column 13 passing through the lower plastic cover 50. The lower end of the lower plastic cover 50 is always tightly bonded to the end surface of the stopper 14. The top cover 20 and the lower plastic cover 50 are snap-fitted together, and the seal 30 is sealed between the top cover 20 and the lower plastic cover 50.

[0028] In this technical solution, the busbar 40 adopts a widened and thickened design, which greatly improves the flow capacity during operation, thereby effectively preventing excessive temperature rise during high current charging and discharging. The width of the transition zone of the busbar 40 can range from 25-35mm, and the overall thickness of the busbar can range from 0.5-1mm. In order to ensure weldability, the thickness of the collecting area 41 and the welding area 42 is thinned by 0.1-0.5mm. The end has a trapezoidal air-avoidance design to maximize the directional ejection of thermal runaway and increase the electrolyte infiltration capacity. By providing a seal 30, the electrolyte in the battery can be prevented from flowing out of the side of the cover plate, further isolating the electrolyte from the outside world, improving the mechanical reliability and airtightness of the structural parts, and increasing the service life of the battery.

[0029] By optimizing the injection molding structure and the busbar structure size, the contact area between components is increased, thereby improving the mechanical strength of the pole, reducing the contact internal resistance, and significantly improving the current capacity of the battery cover.

[0030] A cylindrical battery applied to the above-mentioned battery cover assembly, wherein the cell overcurrent capacity of the cylindrical battery is above 10C, and the temperature rise is less than 15°C under a 10C rate discharge test at room temperature.

[0031] The embodiments of the present application are described above in conjunction with the accompanying drawings. Unless there is a conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are within the protection of this application.

Claims

1. A cover plate assembly for high-rate applications, characterized in that: include: A pole (10), wherein the pole (10) is provided with a busbar (40) on the upper sleeve, the upper end of the busbar (40) is provided with a lower plastic cover (50), the upper end of the lower plastic cover (50) is connected to a sealing member (30), the sealing member (30) is provided with a top cover (20) on the upper sleeve, the middle portion of the top cover (20) is provided with an assembly hole (21), and the pole (10) passes through the assembly hole (21); an upper plastic cover (60) is embedded in the assembly hole (21), the upper end of the upper plastic cover (60) is provided with a terminal (70), and the terminal (70) is clamped on the pole (10), and the terminal (70) is also provided with an explosion-proof valve (80).

2. A cover plate assembly for high-rate applications according to claim 1, characterized in that: The pole (10) comprises a bottom plate portion (11), one end of the bottom plate portion (11) is provided with a boss portion (12) for limiting, the other end of the bottom plate portion (11) is provided with a column portion (13), and a limiting portion (14) is provided at the end of the column portion (13).

3. A cover plate assembly for high-rate applications according to claim 2, characterized in that: The current collecting plate (40) comprises a current collecting area (41) and a welding area (42); a through hole is provided on one side of the current collecting area (41), and the current collecting plate (40) is fitted to the bottom plate portion (11) through the through hole.

4. The cover plate assembly for high-rate applications according to claim 2, characterized in that: The lower plastic cover (50) is annular, and the middle portion of the column portion (13) passes through the lower plastic cover (50), and the lower end of the lower plastic cover (50) is always tightly fitted with the end surface of the limiting portion (14).

5. The cover plate assembly for high-rate applications according to claim 1, characterized in that: The top cover (20) and the lower plastic cover (50) are snap-fitted into one body, and the sealing member (30) is sealed between the top cover (20) and the lower plastic cover (50).

6. The cover plate assembly for high-rate applications according to claim 2, characterized in that: One end of the terminal (70) is tightly fitted to the upper plastic cover (60), and the limiting portion (14) and the terminal (70) are riveted together as a whole.

7. The cover plate assembly for high-rate applications according to claim 2, characterized in that: The diameter of the column portion (13) ranges from 18 mm to 25 mm.

8. The cover plate assembly for high-rate applications according to claim 3, characterized in that: The width of the busbar (40) is in the range of 25 mm to 35 mm, the thickness is in the range of 0.5 mm to 1 mm, the thickness of the current collecting area (41) and the welding area (42) is in the range of 0.1 mm to 0.5 mm, and the end of the busbar (40) has a trapezoidal air-avoiding design.

9. A cylindrical battery, characterized in that : comprising a cover assembly for high-rate applications as claimed in any one of claims 1 to 8, wherein the cylindrical battery has a cell current capacity greater than 10C.

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