Convergence piece with embossed salient points and cylindrical battery with convergence piece

Abstract

The utility model provides a confluence piece with embossed salient points and a cylindrical battery with the confluence piece, the confluence piece comprises a central area and an edge area, and the central area is used for being welded to a shell of the battery; and a plurality of embossed convex points are arranged in the central area and are distributed in a crossed array. In one implementation mode, the crossed array distribution is that the number of the embossed convex points in each row is sequentially in odd-even crossed distribution. In one implementation mode, the knurling convex points in the odd-number rows are located on the symmetry axis of the two knurling convex points in the even-number rows. In one embodiment, the crossed array distribution is that three adjacent embossed salient points are distributed in an equilateral triangle shape. By means of the design of the embossed protruding points, the welding melting area can be increased by 24%, the welding strength of the bottom is improved, the welding firmness degree is improved, meanwhile, the internal resistance of bottom welding points is reduced by 22%, and dissipation of electric energy by the internal resistance is reduced.

Description

Technical Field

[0001] The utility model relates to a bus bar for a battery, and more specifically, to a bus bar with embossed bumps. Further, the utility model also relates to a cylindrical battery having the bus bar. Background Art

[0002] Batteries play an important role in providing power for many daily-use electrical devices. It mainly consists of a cap, a housing, a wound core, an electrolyte, and a bus bar. Through the electrochemical reaction of the active substances in the battery wound core, electrical energy is output to provide power for electrical devices. The bus bar collects the current generated by the active substances in the battery to facilitate the formation of a larger current for external output. Generally, in order to improve the output efficiency of the battery as much as possible, the bus bar needs to be in full contact with the active substances as much as possible. At the same time, in order to maintain the assembly stability of the battery and increase the current-carrying capacity between the connection structures, the bus bar is combined with the battery wound core and the battery housing by welding. However, a relatively large internal resistance is often generated at the welding point position of the bus bar, which in turn affects the electrical energy output of the battery.

[0003] In order to improve the contact performance of the bus bar as much as possible, increase the welding firmness, and reduce the dissipation of electrical energy caused by the relatively high internal resistance, a new bus bar design solution needs to be provided to solve at least part of the above problems. Summary of the Invention

[0004] The purpose of the utility model is to provide a bus bar and a cylindrical battery including the bus bar. It can achieve increased welding firmness, reduced internal resistance, and improved contact performance of the bus bar, thereby reducing the dissipation of electrical energy by the connection structure under working conditions.

[0005] According to one aspect of the utility model, there is provided a bus bar with embossed bumps for a battery,

[0006] The bus bar includes a central region and an edge region, and the central region is used for welding to the housing of the battery;

[0007] The central region is provided with a plurality of embossed bumps, and the embossed bumps are distributed in a crosswise array.

[0008] In one embodiment, the crosswise array distribution is such that the number of embossed bumps in each row is alternately distributed as odd and even numbers.

[0009] In one embodiment, the embossed bumps in the odd rows are located on the symmetry axis of two embossed bumps in the even rows.

[0010] In one embodiment, the crosswise array distribution is such that three adjacent embossed bumps are distributed in an equilateral triangle.

[0011] In one embodiment, the number of the embossed bumps in the central region ranges from 15 to 100, preferably from 30 to 90, and more preferably from 45 to 60.

[0012] In one embodiment, the diameter of the embossed bumps in the central region ranges from 0.3 mm to 0.8 mm, preferably from 0.4 mm to 0.7 mm, and more preferably from 0.5 mm to 0.6 mm.

[0013] In one embodiment, the distance between the centers of the embossed bumps in the central region is from 0.4 mm to 1.2 mm, preferably from 0.5 mm to 1.1 mm, and more preferably from 0.55 mm to 1.00 mm.

[0014] In one embodiment, the height of the embossed bumps ranges from 0.05 mm to 1.00 mm, preferably from 0.10 mm to 0.80 mm, and more preferably from 0.15 mm to 0.60 mm.

[0015] In one embodiment, the embossed bumps are cylindrical, conical, or any convex shape between cylindrical and conical.

[0016] In one embodiment, the current collector includes at least three edge regions.

[0017] In one embodiment, the embossed bumps are arranged in parallel multiple rows, and there is an overlapping part in the parallel direction between adjacent rows of embossed bumps.

[0018] According to another aspect of the present invention, a cylindrical battery is provided, including: the current collector as described above.

[0019] In one embodiment, the cylindrical battery further includes:

[0020] a wound core, one pole of the wound core is welded and combined with the first side of the current collector;

[0021] a housing, the housing includes a cylindrical side wall and a bottom cover, the bottom cover is welded and combined with the second side of the current collector; wherein the welding occurs at the embossed bumps in the central region of the second side.

[0022] It should be understood that the above general description and the following detailed description are exemplary and are only intended to provide an overview or framework for understanding the nature and characteristics of the present invention and the appended claims. As a non-limiting example, various features of the present invention can be combined with each other according to the following embodiments. Description of the Drawings

[0023] To better understand the above and other objects, features, advantages and functions of the present utility model, reference may be made to the preferred embodiments shown in the accompanying drawings. The same reference numerals in the drawings refer to the same components. Those skilled in the art should understand that the drawings are intended to schematically illustrate the preferred embodiments of the present utility model and have no restrictive effect on the scope of the present utility model, and the components in the drawings are not drawn to scale.

[0024] Figure 1 Shows a bus bar with embossed bumps according to some embodiments of the present utility model, wherein the embossed bumps in the central region have a 4×4 bump array (aligned);

[0025] Figure 2 Shows a bus bar with embossed bumps according to other embodiments of the present utility model, wherein the embossed bumps in the central region have a 7×8 bump array (crossed);

[0026] Figure 3 Shows a side view of a bus bar according to an embodiment of the present utility model;

[0027] Figure 4 Shows according to an embodiment of the present utility model Figure 2 A plan view of the welded portion including the embossed bumps in the bus bar of;

[0028] Figure 5 Shows an exploded view of a cylindrical battery according to an embodiment of the present utility model;

[0029] Figure 6 Shows a cross-sectional perspective view after the welding operation is completed according to an embodiment of the present utility model.

[0030] Reference numerals:

[0031] 100 Bus bar

[0032] 111 First side

[0033] 112 Second side

[0034] 113 Central region

[0035] 114 Edge region

[0036] 115 Embossed bump

[0037] 200 Core

[0038] 300 Housing

[0039] 301 Bottom cover Detailed description of the invention

[0040] Referring now to the drawings, specific embodiments of the present utility model will be described in detail. What is described herein is only the preferred embodiment of the present utility model, and those skilled in the art can think of other ways to implement the present utility model based on the preferred embodiment, and such other ways also fall within the scope of the present utility model.

[0041] Unless otherwise clearly stated, there is no intention to require a specific orientation for any device. Therefore, in any case where a device claim does not actually recite the order or direction of individual components, or where the steps are not specifically limited to a particular order in the claims or the specification or where the specific order or direction of the components of the device is not recited, there is no intention to infer its order or direction in any respect.

[0042] Figures 1 to 6 A current collector plate with embossed bumps according to the present utility model and a cylindrical battery using the current collector plate are shown. First of all, it should be noted that the directional terms and positional terms in the present utility model should be understood as relative directions and positions, rather than absolute directions and positions. The directional terms and positional terms in the present utility model can be explained with reference to Figures 1 to 6 the exemplary structure shown.

[0043] The inventor found in the practice of production and research that a large internal resistance will be brought during the welding process of the current collector plate, so that a large amount of electric energy will be converted into heat energy dissipation during actual use, affecting the battery output performance. In order to minimize the dissipation of electric energy by the internal resistance on the basis of ensuring welding stability and improving the current collection ability, in view of the above technical problems, the present utility model provides a current collector plate with embossed bumps, and the embossed bumps can act as micro electrodes. During the welding and assembly process, these embossments will contact the bottom steel shell of the housing, and these embossed bumps will melt first when the welding current passes through. By arranging the embossments in a cross-type dense arrangement (refer to Figure 2 ), more embossed bumps can be pressed by the welding needle during the welding process, and the quantity is more stable, thereby improving the welding consistency. And through verification, compared with the embossments arranged in an aligned dense arrangement (refer to Figure 1 ), the cross-type dense arrangement of embossments can increase the melting area of the welding by 24%, thereby increasing the welding strength at the bottom, and at the same time reducing the internal resistance of the bottom solder joints by 22%, reducing the dissipation of electric energy by the internal resistance.

[0044] Now refer to Figures 2 to 6, according to one aspect of the present utility model, a bus bar with embossed bumps is provided. The bus bar 100 includes a central region 113 and an edge region 114; a plurality of embossed bumps 115 are provided in the central region 113, and the embossed bumps are distributed in a cross-type array. In one embodiment, the cross-type array distribution is such that the number of embossed bumps 115 in each row is alternately odd and even. For example, Figure 2 as shown, from top to bottom, they are 7 - 8 - 7 - 8 - 7 - 8 - 7 - 8 in sequence. As a preferred embodiment, the embossed bumps 115 in the odd rows are located on the axis of symmetry between two embossed bumps 115 in the even rows. As a preferred embodiment, the cross-type array distribution is such that three adjacent embossed bumps 115 are distributed in a substantially equilateral triangle. In one embodiment, as Figure 2 shown, the embossed bumps 115 are substantially square. It should be understood that it is also possible to set the embossed bumps to common geometric shapes such as circular or hexagonal, as long as the above requirements are met.

[0045] In some embodiments, multiple parallel rows of embossed bumps are staggered with each other, and there is an overlapping portion in the parallel direction between the embossed bumps in adjacent rows. Or rather, the embossed bumps extend beyond the connection line of the edges of the embossed bumps in adjacent rows. This can provide more embossed bumps in a limited space, thereby increasing the welding area and reducing the resistance after welding. Of course, optionally, in some other embodiments, there may also be no overlapping portion in the parallel direction between the embossed bumps in adjacent rows.

[0046] For the bus bar 100 of the present utility model, the bumps provided on the surface are in contact with the core or other electrical devices for welding connection. A columnar welding head can be used to heat the bumps of the embossed bumps simultaneously, and the electrodes melt the bumps simultaneously, thereby completing the welding of the bus bar. In this way, the production efficiency can be improved and the processing time can be saved.

[0047] Now please continue to refer to Figures 2 to 4, which shows a specific embodiment of the bump distribution in the central region 113 of the bus bar 100. The number, diameter of the embossed bumps 115, and the distance between the centers of two embossed bumps 115 can be configured according to the given application requirements. Such configuration is for exemplary purposes and should not be regarded as limiting the present utility model. For example, in one embodiment, the number of bumps in the central region 113 can be 15 to 100, preferably 30 to 90, and more preferably 45 to 60. In one implementation, the diameter range of the embossed bumps 115 in the central region 113 is 0.3 mm to 0.8 mm, preferably 0.4 mm to 0.7 mm, and more preferably 0.5 mm to 0.6 mm. In one implementation, the distance between the centers of the embossed bumps 115 in the central region 113 is 0.4 mm to 1.2 mm, preferably 0.5 mm to 1.1 mm, and more preferably 0.55 mm to 1.00 mm.

[0048] Furthermore, the height of the embossed bumps 115 affects the welding pressure, welding time, temperature control, etc. of the welding head. In one implementation, the height range of the embossed bumps 115 is 0.05 mm to 1.00 mm, preferably 0.10 mm to 0.80 mm, and more preferably 0.15 mm to 0.60 mm. Such height of the bumps facilitates arbitrarily controlling the melting and on the other hand can also ensure the welding firmness.

[0049] Regarding the three-dimensional shape of the embossed bumps 115, it can be cylindrical, conical, or any convex shape between cylindrical and conical. Such shape can be easily obtained by those skilled in the art based on experience. The bumps are obtained by the commonly used stamping process in the art. Applying this process is easier to process and has lower processing costs.

[0050] In addition, as Figures 2 to 4 shown, on the other hand, the bus bar 100 includes at least one edge region 114 distributed outside the bus bar 100 relative to the central region 113. Preferably, the bus bar 100 includes at least two edge regions 114, and more preferably, includes at least three edge regions 114 for welding to the core.

[0051] Please continue to refer to Figure 3, in one embodiment, the bus bar 100 has a first side 111 for contacting the core 200 and a second side 112 opposite to the first side 111. In a general battery structure, the second side 112 is usually used to contact the battery housing. However, in some other embodiments, the second side 112 can also be used to contact other electrical components inside the battery. As a preferred embodiment, the embossed bumps 115 in the central region 113 are located at the second side 112, that is, for contacting the battery housing.

[0052] As Figures 5 to 6 shown, according to another aspect of the present invention, a cylindrical battery is provided, and the battery includes: the bus bar 100 as described above.

[0053] Furthermore, according to another aspect of the present invention, a cylindrical battery is provided, and the battery further includes: a core 200, one pole of the core 200 is welded and bonded to the first side 111 of the bus bar 100;

[0054] a housing 300, the housing 300 includes a cylindrical side wall and a bottom cover 301, and the bottom cover 301 is welded and bonded to the second side 112 of the bus bar 100; wherein the welding occurs at the embossed bumps 115 in the central region 113 of the second side 112. Specific embodiments:

[0056] Example 1: 4×4 bump array (aligned type)

[0057] As a comparative example, embossed bumps with a 4×4 aligned bump array are designed in the central region. As Figure 1 shown, the array contains a total of 16 bumps, the array is arranged in a square shape, and the side length of the bump array is 3.6 mm. Each bump has the same three-dimensional shape, the bottom surface of each bump is circular, with a diameter of 0.6 mm, and in the length direction, the distance between the centers of adjacent bumps is 1.0 mm. At this time, when using a welding head with a welding diameter of 2 mm, 4 - 6 bumps can be covered simultaneously for welding.

[0058] Example 2: 7×8 bump array (cross type)

[0059] As an embodiment of the present invention, embossed bumps with a 7×8 cross bump array are designed in the central region. As Figure 2As shown, the array contains a total of 60 bumps. The bumps are arranged in an alternating pattern of 7-8-7-8-7-8-7-8 in each row. The array is rectangular with side lengths of 3.8 mm × 4.0 mm. Each bump has the same three-dimensional shape. The bottom surface of each bump is circular with a diameter of 0.5 mm. The distance between the centers of adjacent bumps is 0.55 mm, 0.58 mm, and 0.62 mm. At this time, when using a welding head with a diameter of 2 mm for welding, 14-19 bumps can be covered for processing.

[0060] By performing welding operations under the same welding parameters, the welding effect parameters of both are evaluated. As shown in Table 1:

[0061] Table 1. Measurement of Welding Effect Parameters under the Same Welding Parameters

[0062]

[0063] It is measured that the internal resistance of the battery of the bus bar in Example 1 at the bottom of the battery cell is 0.32 mΩ. After replacing it with the bus bar of Example 2, the internal resistance at the bottom of the battery cell is 0.25 mΩ, and the internal resistance is reduced by 22%.

[0064] The welding tension, residual area, and residual points of the bus bar in Example 2 are also significantly higher than those of the bus bar in Example 1. Under the parameter of 3.6 kA, the welding tensions of the bus bars in Example 1 and Example 2 meet the specifications, but 1 / 5 of the batteries of the bus bar in Example 1 have no residue.

[0065] Under the welding parameters of 2 ms @ 3.7 KA, the residual area of the bus bar in Example 1 is only 1.266 mm 2 , and the fuse core effect is poor. While the bus bar in Example 2 has a residual area of 1.663 mm 2 The residual area of the welding increases by 24%, and it has a better fuse core effect. When the welding parameter is higher than 3.8 kA, pores will appear in the welding core, which is not conducive to welding operations.

[0066] The above description of the various embodiments of the present invention is provided to those skilled in the art for the purpose of description. It is not intended to exclude or limit the present invention to a single disclosed embodiment. As above, those skilled in the art taught above will understand the various alternatives and modifications of the present invention. Therefore, although some alternative embodiments are specifically described, those of ordinary skill in the art will understand or relatively easily develop other embodiments. The present invention is intended to include all alternatives, modifications, and variations of the present invention described herein, as well as other embodiments that fall within the spirit and scope of the present invention described above.

Claims

1. A busbar having embossed bumps, characterized in that: The busbar (100) comprises a central region (113) and an edge region (114), wherein the central region (113) is used for welding to a battery housing; The central area (113) is provided with a plurality of embossed convex points (115), and the embossed convex points are distributed in a cross array.

2. The busbar according to claim 1, wherein: The cross array distribution is that the number of embossed convex points (115) in each row is cross-distributed in odd and even numbers.

3. The busbar according to claim 2, characterized in that: The embossed convex points (115) in the odd number row are located on the symmetry axis of the two embossed convex points (115) in the even number row.

4. The busbar according to claim 2, characterized in that: The cross array is distributed such that three adjacent embossed convex points (115) are distributed in an equilateral triangle.

5. The busbar according to claim 1, wherein: The number of the embossed protrusions (115) in the central area (113) ranges from 15 to 100.

6. The busbar according to claim 1, characterized in that: The number of the embossed protrusions (115) in the central area (113) ranges from 30 to 90.

7. The busbar according to claim 1, wherein: The number of embossed protrusions (115) in the central area (113) ranges from 45 to 60.

8. The busbar according to claim 1, wherein: The diameter of the embossed protrusions (115) in the central area (113) ranges from 0.3 mm to 0.8 mm.

9. The busbar according to claim 1, characterized in that: The diameter of the embossed protrusions (115) in the central area (113) ranges from 0.4 mm to 0.7 mm.

10. The busbar according to claim 1, wherein: The diameter of the embossed protrusions (115) in the central area (113) ranges from 0.5 mm to 0.6 mm.

11. The busbar according to claim 1, wherein: The distance between the centers of the embossed convex points (115) in the central area (113) is 0.4 mm to 1.2 mm.

12. The busbar according to claim 1, wherein: The distance between the centers of the embossed convex points (115) in the central area (113) is 0.5 mm to 1.1 mm.

13. The busbar according to claim 1, wherein: The distance between the centers of the embossed convex points (115) in the central area (113) is 0.55 mm to 1.00 mm.

14. The busbar according to claim 1, wherein: The height of the embossed protrusions (115) ranges from 0.05 mm to 1.00 mm.

15. The busbar according to claim 1, wherein: The height of the embossed convex points (115) ranges from 0.10 mm to 0.80 mm.

16. The busbar according to claim 1, wherein: The height of the embossed protrusions (115) ranges from 0.15 mm to 0.60 mm.

17. The busbar according to claim 1, wherein: The embossed convex point (115) is cylindrical, conical, or any convex shape between cylindrical and conical.

18. The busbar according to claim 1, wherein: The busbar (100) includes at least three edge regions (114).

19. The busbar according to claim 2, wherein: The embossed convex points (115) are arranged in a plurality of parallel rows, and overlapping portions exist between adjacent rows of embossed convex points in a parallel direction.

20. A cylindrical battery, characterized in that: include: The busbar (100) according to any one of claims 1 to 19.

21. The cylindrical battery according to claim 20, characterized in that: Also includes: A winding core (200), wherein one pole of the winding core (200) is welded to the first side (111) of the busbar (100); A housing (300), the housing (300) comprising a cylindrical side wall and a bottom cover (301), the bottom cover (301) being welded to the second side (112) of the busbar (100); The welding occurs at the embossed point (115) in the central region (113) of the second side (112).

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