Cylindrical battery

Abstract

Cylindrical battery, characterized in that it comprises a cover plate assembly and a battery cell, wherein the battery cell has a winding cell opening; wherein the cover plate assembly comprises the following: a cover plate body (1) which is provided with a through hole (11), wherein the projection of the winding cell opening onto the cover plate body (1) and the through hole (11) are arranged offset from each other; a pole column (2) which is at least partially guided through the through hole (11), wherein the pole column (2) is firmly connected to the cover plate body (1) via the through hole (11); a current collector disk (3) comprising a pole column weld section (31) and a pole flag weld section (32), wherein the pole column weld section (31) is welded to the pole column (2); wherein a first step section (33) is provided between the pole column weld section (31) and the pole flag weld section (32), and wherein, in the arrangement direction of the cover plate assembly and the battery cell, the minimum distance between the pole column weld section (31) and the battery cell is less than the maximum distance between the pole flag weld section (32) and the battery cell, and wherein the ratio A of the height of the first step section (33) to the height of the battery cell satisfies 0.01≤A≤0.03.

Description

Technical area

[0001] The present utility model relates to the technical field of cylindrical batteries and in particular to a cylindrical battery. Background technology

[0002] In some cylindrical batteries, the positions of the winding cell opening and the terminal column are aligned, and during welding, the ejector pin is pushed upwards through the winding cell opening to limit the projection and groove, thus facilitating the welding of the terminal column and the current collector disc. However, in some cylindrical batteries, the positions of the winding cell opening and the groove of the terminal column are offset, leading to a mis-weld between the current collector disc and the terminal column during welding, and the battery cell can be easily damaged during installation. Contents of the invention

[0003] In light of this, the present utility model provides a cylindrical battery to solve the problem that a soldering defect easily occurs when welding the current collector disc and the pole column, and that the pole column or the current collector disc can easily be damaged when interacting.

[0004] The present utility model provides a cylindrical battery comprising a cover plate assembly and a battery cell, wherein the battery cell comprises a winding cell opening, and wherein the cover plate assembly comprises the following: a cover plate body which is provided with a through hole, wherein the projection of the winding cell opening onto the cover plate body and the through hole are arranged offset from each other; a polar column which is at least partially guided through the through-hole, wherein the polar column is firmly connected to the cover plate body via the through-hole; a current collector disk comprising a pole column weld section and a pole flag weld section, wherein the pole column weld section is welded to the pole column, wherein a first step section is provided between the pole flag weld section and the pole column weld section, and in the arrangement direction of the cover plate assembly and the battery cell, the minimum distance between the pole column weld section and the battery cell is less than the maximum distance between the pole flag weld section and the battery cell.

[0005] Advantageous effects: Since the through-hole for connecting the pole columns and the winding cell opening of the battery cell are offset, the current collector disk and pole column cannot be positioned during welding by the ejector pin guided through the winding cell opening. Therefore, the arrangement of the first stage section between the pole tab welding section and the pole column welding section in this embodiment allows the use of a support or a tool clamping device on the first stage section to support the current collector disk during welding of the current collector disk and pole column, thereby tightly connecting the pole column welding section to the pole column. This facilitates the welding of the pole column and current collector disk, prevents soldering failures during welding of the current collector disk and pole column, and avoids damage to the battery cell during interaction.At the same time, due to the arrangement of the first stage section, the minimum distance between the pole column welding section and the battery cell is smaller than the maximum distance between the pole tab welding section and the battery cell, so that a height difference is created between the pole column welding section and the pole tab welding section, which can improve the injection efficiency and the venting performance of the battery cell. Figures

[0006] To more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the figures necessary for use in the specific embodiments or the description of the prior art are briefly presented below. Obviously, the figures described below represent some embodiments of the present utility model, and general technical personnel in this field can create further figures based on these figures without any creative effort. Fig. Figure 1 is a schematic partial representation of a cover plate assembly for a cylindrical battery according to an embodiment of the present utility model from a perspective; Fig. Figure 2 is a schematic partial representation of a cover plate assembly for a cylindrical battery according to an embodiment of the present utility model from a different perspective; Fig. Figure 3 is a schematic representation of a cover plate assembly for a cylindrical battery according to an embodiment of the present utility model; Fig. Figure 4 is a schematic exploded view of a cover plate assembly for a cylindrical battery according to an embodiment of the present utility model; Fig. Figure 5 is another schematic exploded view of a cover plate assembly for a cylindrical battery according to an embodiment of the present utility model; Fig. Figure 6 is a further schematic exploded view of a cover plate assembly for a cylindrical battery according to an embodiment of the present utility model; Fig. Figure 7 is a schematic representation of a current collector disk for a cylindrical battery according to an embodiment of the present utility model from a perspective; Fig. Figure 8 is a schematic representation of a current collector disk for a cylindrical battery according to an embodiment of the present utility model from a different perspective. Reference symbols in the figures:

[0007] 1. Cover plate body; 11. Through hole; 2. Pole column; 21. Groove; 3. Current collector disc; 31. Pole column weld section; 311. Projection; 32. Pole flag weld section; 33. First stage section; 34. Connecting section; 341. Positioning hole; 35. Second stage section; 4. Injection molded element; 41. Deflection hole; 42. Positioning column; 5. Lower insulating element; 6. First sealing element; 7. Second sealing element. Specific embodiments

[0008] To clarify the purpose, technical solution, and advantages of the embodiments of this utility model, the technical solutions in these embodiments are described clearly and completely below in conjunction with the accompanying drawings. It is evident that the described embodiments represent some of the embodiments of this utility model, not all of them. Based on the embodiments of this utility model, all further embodiments that a person skilled in the art would obtain without inventive activity fall within the scope of protection of this utility model.

[0009] The following are exemplary embodiments of the present utility model with reference to the Fig. 1 to 8 described.

[0010] According to the embodiments of the present utility model, a cylindrical battery is provided comprising a cover plate assembly and a battery cell, the battery cell comprising a winding cell opening; the cover plate assembly comprising a cover plate body 1, a pole column 2, and a current collector disk 3; the cover plate body 1 is provided with a through-hole 11, wherein the projection of a winding cell opening onto the cover plate body 1 and the through-hole 11 are arranged offset from each other; the pole column 2 is guided at least partially through the through-hole 11, and the pole column 2 is firmly connected to the cover plate body 1 via the through-hole 11; the current collector disk 3 comprises a pole column weld section 31 and a pole tab weld section 32, wherein the pole column weld section 31 is welded to the pole column 2;A first step section 33 is provided between the terminal flag welding section u32 and the terminal column welding section 31, and in the arrangement direction of the cover plate assembly and the battery cell, the minimum distance between the terminal column welding section 31 and the battery cell is smaller than the maximum distance between the terminal flag welding section 32 and the battery cell.

[0011] Since the through-hole 11 for connecting the pole columns 2 and the winding cell opening of the battery cell are offset, the current collector disk 3 and the pole column 2 cannot be positioned by the ejector pin guided through the winding cell opening during welding. Therefore, in this embodiment, the arrangement of the first stage section 33 between the pole tab welding section 31 and the pole column welding section 32 allows the use of a support or a tool clamping device on the first stage section 33 to support the current collector disk 3 during welding of the current collector disk 3 and the pole column 2. This tightly connects the pole column welding section 31 to the pole column 2, facilitating the welding of the pole column 2 and the current collector disk 3, preventing soldering failures during welding, and avoiding damage to the battery cell during this interaction.At the same time, due to the arrangement of the first stage section 33, the minimum distance between the pole column welding section 31 and the battery cell is smaller than the maximum distance between the pole tab welding section 32 and the battery cell, so that a height difference arises between pole column welding section 31 and pole tab welding section 32, which can improve the injection efficiency and the venting performance of the battery cell.

[0012] In one embodiment, the pole column 2 is provided with a groove 21; the pole column weld section 31 is provided with a projection 311; at least a part of the projection 311 is arranged in the groove 21 and is welded to the pole column 2.

[0013] In one embodiment, the height difference h of the first step section 33 in the arrangement direction of the cover plate assembly and the battery cells is in the range of 0.1 mm≤h≤2 mm.

[0014] The height difference of the first stage section 22 is in the range of 0.1 mm to 2 mm, which not only provides support for welding current collector disc 3 and pole column 2, but also prevents a significant waste of battery interior space due to an excessive height difference; in addition, this height difference in the range of 0.1 mm to 2 mm facilitates venting in the event of thermal runaway and facilitates the penetration of electrolyte during injection.

[0015] In a specific embodiment, the height difference h of the first step section 33 in the arrangement direction of the cover plate assembly and the battery cell is 0.1 mm.

[0016] In another specific embodiment, the height difference h of the first step section 33 in the arrangement direction of the cover plate assembly and the battery cell is 2 mm.

[0017] In another specific embodiment, the height difference h of the first step section 33 in the arrangement direction of the cover plate assembly and the battery cell is 1 mm.

[0018] In one embodiment, the ratio A of the height of the first stage section 33 to the height of the battery cell in the arrangement direction of the cover plate assembly and the battery cells is 0.01≤A≤0.03.

[0019] In one embodiment, the height difference h of the first step section 33 is in the range of 0.1 mm to 2 mm and the height of the battery cell is in the range of 70 mm to 200 mm.

[0020] The ratio A of the height of the first stage section 33 to the height of the battery cell must not be too high, as this would otherwise impair the height of the battery cell of the cylindrical battery and thus the capacity of the cylindrical battery; the ratio A of the height of the first stage section 33 to the height of the battery cell must not be too low, as this would otherwise impair the injection efficiency of the cylindrical battery and the venting performance of the battery cell; therefore, if the ratio A of the height of the first stage section 33 to the height of the battery cell is 0.01 ≤ A ≤ 0.03, this can ensure the height of the battery cell of the cylindrical battery and the capacity of the cylindrical battery without impairing the injection efficiency of the cylindrical battery and the venting performance of the battery cell.

[0021] In a specific embodiment, the ratio A of the height of the first stage section 33 to the height of the battery cell can be 0.01, 0.03 or 0.02 in the arrangement direction of the cover plate assembly and the battery cell.

[0022] In a specific embodiment, the height of the battery cell can be 70 mm, 200 mm or 135 mm.

[0023] In one embodiment, the cylindrical battery further comprises a support element, wherein the support element is arranged between the pole column weld section 31 and the battery cell and is located at the first stage section 33, wherein the support element consists of an insulating material.

[0024] The support element is located on the first stage section 33 and is arranged between the pole column welding section 31 and the battery cell, which improves the stability of the connection point when connecting the current collector disc 3 with the pole tab, thereby ensuring the contact area between the battery cell and the current collector disc 3 when placing the battery cell on the current collector disc 3 and preventing damage to the battery cell due to insufficient contact area.

[0025] In one embodiment, the cover plate body 1 has two through holes 11 spaced at intervals, and the pole column 2 comprises a first pole column and a second pole column, wherein the first pole column and the second pole column are each firmly connected to the cover plate body 1 by the two through holes 11 and the polarities of the first pole column and the second pole column are opposite; the current collector disk 3 comprises a first current collector disk and a second current collector disk, wherein the first current collector disk and the second current collector disk are arranged at intervals, the pole column weld section 31 of the first current collector disk is connected to the first pole column, and the pole column weld section 31 of the second current collector disk is connected to the second pole column; the height difference h of the first current collector disk and the height difference h of the second current collector disk both satisfy 0.5 mm≤h≤2 mm.

[0026] The cover plate body 1 is provided with two through holes 11, each of which can be connected to the first pole column and the second pole column, and the first current collector disk and the second current collector disk are arranged at intervals to avoid short circuits and to prevent problems such as damage caused by voltage pulls between the first current collector disk and the second current collector disk during the welding process.

[0027] In a specific embodiment, a pole column weld section 31 and a pole flag weld section 32 are provided on the first current collector disk and the second current collector disk, wherein the pole flag weld section 32 of the first current collector disk is connected to the positive terminal flag of the battery cell and the first pole column is connected to the pole column weld section 31 of the first current collector disk, so that the positive terminal of the cylindrical battery is formed; wherein the pole flag weld section 32 of the second current collector disk is connected to the negative terminal flag of the battery cell and the second pole column is connected to the pole column weld section 31 of the second current collector disk, so that the negative terminal of the cylindrical battery is formed.

[0028] In a preferred embodiment, two through holes 11 are provided in the cover plate body 1, each connected to the first pole column and the second pole column, wherein the pole column weld section 31 of the first current collector disk is connected to the first pole column and the pole column weld section 31 of the second current collector disk is connected to the second pole column, such that the positive terminal tab of the battery cell and the negative terminal tab of the battery cell are located at one end of the battery cell, i.e., at the end of the battery cell facing the cover plate body 1; the positive terminal tab of the battery cell and the negative terminal tab of the battery cell are spaced apart and each is welded to the pole tab weld section 32 of the first current collector disk and the pole tab weld section 32 of the second current collector disk.

[0029] In a specific embodiment, the height difference of the first step section 33 of the first current collector disk can be 0.5 mm, 2 mm, or 1.2 mm. The height difference of the first step section 33 of the second current collector disk can be 0.5 mm, 2 mm, or 1.2 mm.

[0030] In one embodiment, the projection of the winding cell opening on the cover plate body 1 is located between the first pole column and the second pole column, and the height difference h of the first current collector disk and the height difference h of the second current collector disk both satisfy 0.5 mm≤h≤1.8 mm.

[0031] In a specific embodiment, the projection of the winding cell opening on the cover plate body 1 is located between the first pole column and the second pole column, and the height difference h of the first current collector disk and the height difference h of the second current collector disk can be 0.5 mm, or 1.8 mm, or 1.2 mm.

[0032] In one embodiment, the first pole column and the second pole column are distributed centrally symmetrically on the cover plate body 1, and the height difference h of the first current collector disk and the height difference h of the second current collector disk both satisfy 0.5 mm≤h≤1.5 mm.

[0033] In a specific embodiment, the first pole column and the second pole column are distributed centrally symmetrically on the cover plate body 1, and the height difference h of the first current collector disk and the height difference h of the second current collector disk can be 0.5 mm, or 1.5 mm, or 1 mm.

[0034] In one embodiment, a minimum distance D between the pole column welding section 31 of the first current collector disk and the pole flag welding section 32 of the second current collector disk 0.7 mm≤D≤30 mm.

[0035] In a specific embodiment, the minimum distance D between the pole column welding section 31 of the first current collector disk and the pole flag welding section 32 of the second current collector disk can be 0.7 mm, 30 mm or 15 mm.

[0036] In one embodiment, a minimum distance E between the pole flag welding section 32 of the first current collector disk and the pole column welding section 31 of the second current collector disk 0.7 mm≤E≤30 mm.

[0037] In a specific embodiment, the minimum distance E between the pole flag weld section 32 of the first current collector disk and the pole column weld section 31 of the second current collector disk can be 0.7 mm, 30 mm or 15 mm.

[0038] In one embodiment, the pole column 2 comprises a first pole column and a second pole column, wherein the first pole column and the second pole column are each located at the two ends of the battery cell and both ends of the battery cell are provided with the cover plate body 1, and wherein the first pole column and the second pole column are fixedly connected to the two cover plate bodies 1 via two through holes 11 and the first pole column and the second pole column have opposite polarities; or one end of the battery cell is provided with the cover plate body 1, the first pole column is fixedly connected to the cover plate body 1 via the through hole 11, and the battery housing at the other end of the battery cell is provided with a terminal hole, the projection of the winding cell opening onto the battery housing is arranged offset from the terminal hole, and the second pole column is fixedly connected to the battery housing via the terminal hole; The current collector disk 3 comprises a first current collector disk and a second current collector disk, wherein the pole column weld section 31 of the first current collector disk is connected to the first pole column, and the pole column weld section 31 of the second current collector disk is connected to the second pole column; the height difference h of the first current collector disk and the height difference h of the second current collector disk both satisfy 0.1 mm≤h≤1 mm.

[0039] If the first pole column and the second pole column are located at opposite ends of the battery cell, the height difference between the first step section of the first current collector disk and the height difference between the first step section of the second current collector disk does not need to be set too large in order to avoid taking up too much space in the longitudinal direction of the battery cell.

[0040] In a specific embodiment, the first pole column and the second pole column are located at the two ends of the battery cell, and the height difference h of the first current collector disk and the height difference h of the second current collector disk can be 0.1 mm, or 1 mm, or 0.5 mm.

[0041] In one embodiment, the ratio A of the height of the first step section 33 to the height of the battery cell in the arrangement direction of the cover plate assembly and the battery cell is 0.01≤A≤0.03; the height difference h of the first step section 33 is in the range of 0.1 mm to 2 mm and the height range of the battery cell is in the range of 70 mm to 200 mm.

[0042] In a specific embodiment, the ratio A of the height of the first stage section 33 to the height of the battery cell can be 0.01, 0.03, or 0.02 in the arrangement direction of the cover plate assembly and the battery cell; the height difference h of the first stage section 33 can be 0.1 mm, 2 mm, or 1 mm; the height of the battery cell can be 70 mm, 200 mm, or 135 mm. In one embodiment, the ratio B of the shortest distance between the terminal weld section 32 of the first current collector disk and the terminal weld section 32 of the second current collector disk to the radial width of the battery cell satisfies 1 / 30 ≤ B ≤ 1 / 2.

[0043] The larger the ratio B of the shortest distance between the terminal weld section 32 of the first current collector disk and the terminal weld section 32 of the second current collector disk to the radial width of the battery cell, the smaller the radial width of the battery cell. If the radial width of the battery cell is too small, the insulation performance cannot be guaranteed. Conversely, the smaller the ratio B of the shortest distance between the terminal weld section 32 of the first current collector disk and the terminal weld section 32 of the second current collector disk to the radial width of the battery cell, the larger the radial width of the battery cell.If the radial width of the battery cell is too large, the area of ​​the terminal weld section 32 of the current collector disk 3 is reduced, and the weld area between the current collector disk 3 and the tab of the battery cell is reduced, thereby affecting the flow area.

[0044] In a specific embodiment, the ratio B of the shortest distance between the terminal weld section 32 of the first current collector disk and the terminal weld section 32 of the second current collector disk to the radial width of the battery cell is 1 / 30.

[0045] In another specific embodiment, the ratio B of the shortest distance between the terminal weld section 32 of the first current collector disk and the terminal weld section 32 of the second current collector disk to the radial width of the battery cell is 1 / 2.

[0046] In a preferred embodiment, the shortest distance between the pole-flap weld section 32 of the first current collector disk and the pole-flap weld section 32 of the second current collector disk is in the range of 1 mm to 30 mm. The radial width of the cover plate is 30 mm to 60 mm.

[0047] In one embodiment, on each current collector disk 3, the ratio C of the area of ​​the pole flag weld section 32 to the area of ​​the pole column weld section 31 is 0.5≤C≤4.

[0048] If on each current collector disk 3 the ratio C of the area of ​​the pole-flap welding section 32 to the area of ​​the pole-column welding section 31 is too small, the area of ​​the pole-column welding section 31 of the current collector disk 3 is too small in relation to the area of ​​the pole-flap welding section 32, and the overcurrent capacitance of the pole-column welding section 31 and the overcurrent capacitance of the pole-flap welding section 32 are unbalanced; If the ratio C of the area of ​​the pole-flap welding section 32 to the area of ​​the pole-column welding section 31 is too large, the area of ​​the pole-column welding section 31 is too small in relation to the area of ​​the pole-flap welding section 32, which leads to a reduction in the overcurrent capacity of the pole-column welding section 31, and also leads to the distance between the pole-flap welding section 32 of the first current collector disk and the pole-flap welding section 32 of the second current collector disk being too small.the two are too close together, which impairs the insulation.

[0049] In a specific embodiment, the ratio C of the area of ​​the pole vane weld section 32 to the area of ​​the pole column weld section 31 on each current collector disk 3 is 0.5.

[0050] In another specific embodiment, the ratio C of the area of ​​the tab weld 32 to the area of ​​the pole column weld section 31 on each current collector disk 3 is 4.

[0051] In a preferred embodiment, the ratio C of the area of ​​the pole-flap welding section 32 to the area of ​​the pole-column welding section 31 on each current collector disk 3 is 1, the area of ​​the pole-flap welding section 32 on the first current collector disk is 10 mm2 and the area of ​​the pole-flap welding section 32 on the second current collector disk is 8 mm2.

[0052] In one embodiment, an injection molding element 4 is further provided, wherein the injection molding element 4 is connected to the cover plate body 1, the current collector disk 3 is arranged between the injection molding element 4 and the cover plate body 1, a deflection hole 41 is provided on the injection molding element 4, and the pole column welding section 31 is arranged at the deflection hole 41.

[0053] The current collector disc 3 is arranged between the injection molded element 4 and the cover plate body 1, and the injection molded element 4 can not only improve the connection stability between the current collector disc 3 and the cover plate body 1; but also allow the pole column welding section 31 to exit through the escape hole 41, thereby ensuring the connection between the pole flag welding section 32 and the pole flag of the battery cell and improving the connection convenience between the pole column welding section 31 and the pole column 2.

[0054] Preferably, the pole column welding section 31 and the pole flag welding section 32 are arranged at the diverting hole 41.

[0055] In a specific embodiment, two through holes 11 are provided at intervals in the cover plate body 1, and the pole column 2 comprises a first pole column and a second pole column, wherein the first pole column and the second pole column are each firmly connected to the cover plate body 1 by the two through holes 11; the current collector disk 3 comprises a first current collector disk and a second current collector disk, wherein the first current collector disk and the second current collector disk are arranged at intervals, the pole column weld section 31 of the first current collector disk is connected to the first pole column, and the pole column weld section 31 of the second current collector disk is connected to the second pole column.The injection molded element 4 is provided with two escape holes 41, and the two escape holes 41 are spaced apart, with the pole column weld section 31 and the pole flag weld section 32 of the first current collector disk emerging through one escape hole 41, and the pole column weld section 31 and the pole flag weld section 32 of the second current collector disk emerging through the other escape hole 41. Due to the insulating properties of the injection molded element 4 itself, the injection molded element 4 can perform an insulating and separating function between the first and second current collector disks between the two escape holes 41.

[0056] In one embodiment, a connecting section 34 is further provided on the current collector disk 3, and the pole column welding section 31 and the connecting section 34 are each arranged at both ends of the pole tab welding section 32, and a second step section 35 is provided between the connecting section 34 and the pole tab welding section 32. The minimum distance between the connecting section 34 and the battery cell is less than the maximum distance between the pole tab welding section 32 and the battery cell, and at least part of the connecting section 34 is connected between the injection-molded element 4 and the cover plate body 1.

[0057] By arranging the connecting section 34, the stability of the current collector disk 3 can be improved over the injection molded element 4 and the cover plate body 1, and by arranging the second stage section 35, the pole flag welding section 32, which is spaced apart from the cover plate body 1, can have a relatively flat surface, thereby improving the welding effect between the pole flag welding section 32 and the pole column and ensuring the contact area between the pole flag welding section 32 and the battery cell.

[0058] In one embodiment, a positioning hole 341 is provided on the connecting section 34 and a positioning column 42 is provided on the injection molded element 4, and the positioning column 42 is positioned and inserted into the positioning hole 341.

[0059] By positioning and inserting the current collector disc 3 between the positioning hole 341 and the positioning column 42, it can be positioned and fixed during connection, thus ensuring a better connection effect. A positioning hole 341 is provided on the connection section 34, and a positioning column 42 is provided on the injection-molded part 4. The positioning hole 341 and the positioning column 42 can also be concealed to save space.

[0060] In one embodiment, at least two positioning holes 341 are provided and the at least two positioning holes 341 are arranged at intervals.

[0061] The at least two positioning holes are arranged at intervals 341, which prevents the current collector disk 3 from twisting and thus ensures good positioning.

[0062] In a particular embodiment, at least two positioning holes 341 are distributed at intervals along the radial direction of the current collector disk 3. Preferably, two positioning holes 341 are provided, wherein the positioning holes 341 are both circular and arranged at intervals in the radial direction of the current collector disk 3, and the shape of the positioning column 42 corresponds to the shape of the positioning hole 341.

[0063] In a particular embodiment, two through holes 11 are provided at intervals in the cover plate body 1, and the pole column 2 comprises a first pole column and a second pole column, and the first pole column and the second pole column are each firmly connected to the cover plate body 1 by the two through holes 11; the current collector disk 3 comprises a first current collector disk and a second current collector disk, and the first current collector disk and the second current collector disk are arranged at intervals, and the pole column weld section 31 of the first current collector disk is connected to the first pole column, and the pole column weld section 31 of the second current collector disk is connected to the second pole column.The connecting section 34 of the first current collector disk is opposite the pole column weld section 31 of the second current collector disk and is spaced apart from it; the connecting section 34 of the second current collector disk is opposite the pole column weld section 31 of the first current collector disk and is spaced apart from it. The pole vane weld section 32 has the shape of an annular sector, and the center of the pole vane weld section 32 of the first current collector disk coincides with the center of the pole vane weld section 32 of the second current collector disk.

[0064] In a particular embodiment, the cover plate assembly further comprises a lower insulating element 5, which is arranged between the cover plate body 1 and the current collector disk 3, and the lower insulating element 5 is provided with a through-hole, wherein the through-hole runs coaxially to the through-hole 11 and is arranged accordingly, and the pole column 2 is firmly connected to the through-hole and the through-hole 11.

[0065] In a further embodiment, a first limiting flange and a second limiting flange are provided at each end of the pole column 2, and the cover plate body 1 and the lower insulating element 5 are arranged between the first limiting flange and the second limiting flange. The lower insulating element 5 is plate-shaped. The cover plate assembly further comprises a first sealing element 6 and a second sealing element 7, wherein the first sealing element 6 surrounds the outer circumference of the pole column 2 and is arranged between the lower insulating element 5 and the first limiting flange; wherein the second sealing element 7 surrounds the outer circumference of the pole column 2 and is arranged between the cover plate body 1 and the second limiting flange.

[0066] In a preferred embodiment, the transition between the first step section 33 and the pole column welding section 31 is smooth, thereby avoiding the formation of sharp edges between the first step section 33 and the pole column welding section 31, which could damage the cover plate body 1 and the lower insulating element 5 during joining.

[0067] In a preferred embodiment, the transition between the first step section 33 and the terminal weld section 32 is smooth, thereby avoiding the formation of sharp edges between the first step section 33 and the terminal weld section 32 that could damage the battery cell during connection.

[0068] Although the embodiments of the present utility model are described in conjunction with the figures, the person skilled in the art may make various modifications and variations without departing from the spirit and scope of the present utility model, and such modifications and variations are all within the scope of protection defined by the attached claims.

Claims

[1] Cylindrical battery, characterized by that it comprises a cover plate assembly and a battery cell, wherein the battery cell has a winding cell opening; wherein the cover plate assembly comprises the following: a cover plate body (1) which is provided with a through hole (11), wherein the projection of the winding cell opening onto the cover plate body (1) and the through hole (11) are arranged offset from each other; a pole column (2) which is at least partially guided through the through hole (11), wherein the pole column (2) is firmly connected to the cover plate body (1) via the through hole (11); a current collector disk (3) comprising a pole column weld section (31) and a pole flag weld section (32), wherein the pole column weld section (31) is welded to the pole column (2); wherein a first step section (33) is provided between the pole column weld section (31) and the pole flag weld section (32), and wherein, in the arrangement direction of the cover plate assembly and the battery cell, the minimum distance between the pole column weld section (31) and the battery cell is less than the maximum distance between the pole flag weld section (32) and the battery cell, and wherein the ratio A of the height of the first step section (33) to the height of the battery cell satisfies 0.01≤A≤0.

03. [2] Cylindrical battery according to claim 1, characterized by , that the height difference h of the first step section (33) in the arrangement direction of the cover plate assembly and the battery cells is in the range of 0.1 mm≤h≤2 mm. [3] Cylindrical battery according to claim 2, characterized bythat the cover plate body (1) has two through holes (11) at intervals, and the pole column (2) comprises a first pole column and a second pole column, the first pole column and the second pole column being located at one end of the battery cell, the first pole column and the second pole column each being firmly connected to the cover plate body (1) by one of the two through holes (11), and the polarities of the first pole column and the second pole column being opposite; that the current collector disk (3) comprises a first current collector disk and a second current collector disk, the first current collector disk and the second current collector disk being arranged at intervals, and the pole column weld section (31) of the first current collector disk being connected to the first pole column, and the pole column weld section (31) of the second current collector disk being connected to the second pole column;where the height difference h of the first current collector disk and the height difference h of the second current collector disk both satisfy 0.5 mm ≤ h ≤ 2 mm. [4] Cylindrical battery according to claim 2, characterized by, that the pole column (2) comprises a first pole column and a second pole column, wherein the first pole column and the second pole column are each located at the two ends of the battery cell and both ends of the battery cell are provided with the cover plate body (1), and wherein the first pole column and the second pole column are each firmly connected to the two cover plate bodies (1) by one of the two through holes (11) and the polarities of the first pole column and the second pole column are opposite; or wherein one end of the battery cell is provided with the cover plate body (1), the first pole column is firmly connected to the cover plate body (1) via the through hole (11), and the battery housing is provided with a terminal hole at the other end of the battery cell, the projection of the winding cell opening onto the battery housing is arranged offset from the terminal hole, and the second pole column is firmly connected to the battery housing via the terminal hole;that the current collector disk (3) comprises a first current collector disk and a second current collector disk, wherein the pole column weld section (31) of the first current collector disk is connected to the first pole column, and the pole column weld section (31) of the second current collector disk is connected to the second pole column; wherein the height difference h of the first current collector disk and the height difference h of the second current collector disk both satisfy 0.1 mm ≤ h ≤ 1 mm.; [5] Cylindrical battery according to claim 3, characterized by , that the projection of the winding cell opening on the cover plate body (1) is located between the first pole column and the second pole column and the height difference h of the first current collector disk and the height difference h of the second current collector disk both satisfy 0.5 mm≤h≤1.8 mm. [6] Cylindrical battery according to claim 5, characterized by, that the first pole column and the second pole column are distributed centrally symmetrically on the cover plate body (1) and that the height difference h of the first current collector disk and the height difference h of the second current collector disk both satisfy 0.5 mm≤h≤1.5 mm. [7] Cylindrical battery according to one of claims 3, 5 or 6, characterized by , that the ratio B of the shortest distance between the pole-flap weld section (32) of the first current collector disk and the pole-flap weld section (32) of the second current collector disk to the radial width of the cover plate body is 1 / 30≤B≤1 / 2. [8] Cylindrical battery according to one of claims 3, 5 or 6, characterized by , that on each current collector disk (3) the ratio C of the area of ​​the pole flag weld section (32) to the area of ​​the pole column weld section (31) 0.5≤C≤4 is satisfied. [9] Cylindrical battery according to one of claims 3, 5 or 6, characterized by, that the minimum distance D between the pole column welding section (31) of the first current collector disk and the pole flag welding section (32) of the second current collector disk meets 0.7 mm≤D≤30 mm. [10] Cylindrical battery according to one of claims 3, 5 or 6, characterized by , that the minimum distance E between the pole flag welding section (32) of the first current collector disk and the pole column welding section (31) of the second current collector disk meets 0.7 mm≤E≤30 mm. [11] Cylindrical battery according to any one of claims 1 to 6, characterized by , that the pole column (2) is provided with a groove (21); the pole column weld section (31) is provided with a projection (311); at least a part of the projection (311) is arranged in the groove (21) and is welded to the pole column (2). [12] Cylindrical battery according to any one of claims 1 to 6, characterized by, that the cylindrical battery further comprises a support element arranged between the pole column weld section (31) and the battery cell and located at the first stage section (33), wherein the support element consists of an insulating material

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