End cover assembly and cylindrical battery

Abstract

The utility model relates to the technical field of batteries, in particular to an end cover assembly and a cylindrical battery, and the end cover assembly comprises a cover plate, an upper pole and a lower pole; wherein the upper pole is arranged on the outer side of the cover plate; the lower pole is mounted on the inner side of the cover plate; a first lug boss is formed on one side, close to the upper pole, of the lower pole, and a corresponding first groove part is formed on one side, far away from the upper pole, of the lower pole; a pole through hole is formed in the cover plate, a second protruding part is formed on the upper pole, the second protruding part and the first protruding part both extend into the pole through hole, and the second protruding part and the first protruding part abut against each other and are connected in a welding mode. It can be seen that the pole is divided into the upper pole and the lower pole, the lower pole is arranged to be of the structure with one side in the protruding shape and the other side in the groove shape, then after the upper pole and the lower pole are preliminarily assembled, the upper pole and the lower pole can be welded from the groove side, the process cost and the material cost are low, and the production efficiency is high.

Description

Technical Field

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

[0002] At present, the pole of the cylindrical battery end cover is often prepared by riveting technology. Specifically, the pole includes a rivet block and a rivet, wherein the rivet block is installed on the outside of the cover plate, and a through hole is provided on the cover plate directly below the center of the rivet block, and the rivet extends from the through hole into the rivet block for fixed connection. This riveting structure has high cost and low efficiency, and the rivet material is high in cost. Utility Model Content

[0003] The purpose of the present application is to provide an end cover assembly and a cylindrical battery, which to a certain extent solves the technical problems in the prior art that the poles of the cylindrical battery end covers are often prepared by riveting processes, which have high process costs, low efficiency, and a large amount of rivet materials and high costs.

[0004] The present application provides an end cap assembly, comprising: a cover plate, an upper pole and a lower pole; wherein the upper pole is mounted on the outer side of the cover plate; and the lower pole is mounted on the inner side of the cover plate;

[0005] A first protrusion is formed on a side of the lower pole close to the upper pole, and a corresponding first groove is formed on a side of the lower pole away from the upper pole;

[0006] The cover plate is formed with a pole through hole, the upper pole is formed with a second protrusion, and the second protrusion and the first protrusion both extend into the pole through hole, and the second protrusion and the first protrusion abut against each other and are connected by welding.

[0007] In the above technical solution, further, the first protrusion and the second protrusion are plugged together.

[0008] In any of the above technical solutions, further, the first protrusion is formed with a first positioning hole communicating with the first groove, and the second protrusion is inserted into the first positioning hole.

[0009] In any of the above technical solutions, further, the end cover assembly also includes a lower plastic and a current collecting plate; wherein the lower pole passes through the current collecting plate and the lower plastic in sequence and then abuts against the upper pole through the pole through hole on the cover plate;

[0010] The peripheral structure of the lower pole located at the first protrusion is a flange, and along the height direction of the cover plate, the flange and the cover plate press the partial structure of the lower plastic and the partial structure of the collecting plate located therebetween.

[0011] In any of the above technical solutions, further, the outer edge of the flange is provided with a step groove with an L-shaped cross-section, the structure of the collecting plate sleeved on the outer periphery of the first protrusion is installed in the step groove, and the two are connected by welding.

[0012] In any of the above technical solutions, further, a positioning boss is formed on one of the cover plate and the lower plastic, a positioning groove is formed on the other of the cover plate and the lower plastic, and the positioning boss is installed in the positioning groove.

[0013] In any of the above technical solutions, further, a plurality of ribs are formed on one side of the lower plastic close to the collecting plate, wherein at least one of the ribs abuts against one side of the collecting plate, and at least another of the ribs abuts against the other opposite side of the collecting plate, so as to clamp the collecting plate and the lower plastic together.

[0014] In any of the above technical solutions, further, the end cover assembly also includes an upper plastic, a boss is formed on one side of the upper pole close to the lower pole, and the second protrusion passes through the boss and cooperates with the lower pole; the upper plastic sleeve is arranged on the boss, and the upper plastic is formed with an avoidance hole for avoiding the second protrusion of the pole;

[0015] A sink is formed on the outer side of the cover plate and is located directly above the pole and connected to the pole through hole, and the upper plastic is installed in the sink; a compensation protrusion corresponding to the sink is formed on the inner side of the cover plate, and an avoidance groove is formed on the lower plastic, and the compensation protrusion is installed in the avoidance groove.

[0016] In any of the above technical solutions, further, the end cover assembly also includes a sealing ring, which is installed in the pole through hole and is pressed by the outer wall of the first protrusion and the inner wall of the pole through hole.

[0017] In any of the above technical solutions, further, the end cover assembly also includes an explosion-proof valve, the explosion-proof valve is installed on the cover plate, and the cover plate is formed with an exhaust through hole connected to the explosion-proof valve.

[0018] In any of the above technical solutions, further, the cover plate is formed with a liquid injection through hole.

[0019] The present application also provides a cylindrical battery, comprising an end cover assembly as described in any of the above technical solutions, and thus having all the beneficial technical effects of the end cover assembly, which will not be described in detail herein.

[0020] In the above technical solution, further, the cylindrical battery also includes a winding core and a shell; wherein the winding core is arranged in the shell; an opening is formed at at least one end of the shell along its height direction, and the opening is provided with the cover plate assembly, and the collecting plate of the end cover assembly is connected to the pole ear of the winding core by welding; the cover plate of the cover plate assembly is buckled at the opening of the shell and connected by welding.

[0021] Compared with the prior art, the beneficial effects of this application are:

[0022] The end cover assembly provided in the present application divides the pole into an upper pole and a lower pole, and the lower pole is configured to have a convex shape on one side and a groove shape on the other side. Then, after the upper pole and the lower pole are initially assembled, the upper pole and the lower pole can be welded from the groove side, such as by laser welding. Compared with the riveting process in the prior art, the operation is simpler and more convenient, that is, the process is simplified, the process cost is reduced, and the production efficiency is improved. In addition, one side of the lower pole is in a groove shape, which greatly reduces the material cost compared with the solid rivet in the prior art.

[0023] In addition, the upper surface of the upper pole does not need to be riveted, making the upper surface of the upper pole smoother and eliminating the need for a leveling process, further reducing process costs and improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 A schematic diagram of the structure of the cover plate provided in an embodiment of the present application;

[0026] Figure 2 Another schematic diagram of the structure of the cover plate provided in the embodiment of the present application;

[0027] Figure 3 A schematic diagram of the structure of the lower pole provided in an embodiment of the present application;

[0028] Figure 4 Another schematic diagram of the structure of the lower pole provided in the embodiment of the present application;

[0029] Figure 5 Another structural schematic diagram of the lower pole provided in the embodiment of the present application;

[0030] Figure 6 for Figure 5 Cross-sectional view along section AA;

[0031] Figure 7 Another schematic diagram of the structure of the upper pole provided in an embodiment of the present application;

[0032] Figure 8 Another structural schematic diagram of the upper pole provided in an embodiment of the present application;

[0033] Fig. 9 A schematic diagram of the structure of the upper plastic provided in an embodiment of the present application;

[0034] Fig.10 A schematic diagram of the structure of the lower plastic provided in an embodiment of the present application;

[0035] Fig.11 Another schematic diagram of the structure of the lower plastic provided in the embodiment of the present application;

[0036] Fig.12 An exploded view of an end cap assembly provided in an embodiment of the present application;

[0037] Fig.13 An assembly diagram of an end cap assembly provided in an embodiment of the present application (it should be noted that the collecting plate in the figure is in an unfolded state, i.e., not bent);

[0038] Fig.14 for Fig.13 Cross-sectional view along section BB;

[0039] Fig.15 for Fig.14 Schematic diagram of the enlarged structure at point C.

[0040] Reference numerals:

[0041] 1-cover plate, 11-sunk platform, 12-pole through hole, 13-compensating protrusion, 14-positioning groove, 15-liquid injection through hole, 16-explosion-proof valve installation through hole, 2-upper pole, 21-second protrusion, 22-boss, 23-L-shaped step installation groove, 24-body, 3-lower pole, 31-first protrusion, 32-first groove, 33-flange, 34-step groove, 35-first positioning hole, 4-lower plastic, 41-positioning protrusion, 42-avoidance groove, 43-convex rib, 5-collecting plate, 6-upper plastic, 7-sealing ring. DETAILED DESCRIPTION

[0042] The technical solution of the present application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0043] The components of the embodiments of the present application generally described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed, but merely represents the selected embodiments of the present application.

[0044] Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative work shall fall within the scope of protection of this application.

[0045] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0046] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0047] Refer to the following Figures 1 to 15 An end cap assembly and a cylindrical battery according to some embodiments of the present application are described.

[0048] Embodiment 1

[0049] See also Figures 12 to 15 As shown, an embodiment of the present application provides an end cap assembly, comprising: a cover plate 1, an upper pole 2 and a lower pole 3; wherein the upper pole 2 is mounted on the outer side of the cover plate 1; and the lower pole 3 is mounted on the inner side of the cover plate 1. It should be noted that: the inner side here refers to the side close to the battery cell, and the outer side here refers to the side away from the battery cell, that is, close to the outside of the battery;

[0050] A first protrusion 31 is formed on one side of the lower pole 3 close to the upper pole 2, and a corresponding first groove 32 is formed on one side of the lower pole 3 away from the upper pole 2, that is, the side of the first protrusion 31 away from the lower pole 3 is in a groove shape, and preferably, the first protrusion 31 of the lower pole 3 can be formed by stamping so that one side is in a protrusion shape and the other side is in a groove shape;

[0051] The cover plate 1 is formed with a pole through hole 12, and the upper pole 2 is formed with a second protrusion 21, and the second protrusion 21 and the first protrusion 31 both extend into the pole through hole 12, and the second protrusion 21 and the first protrusion 31 abut against each other and are connected by welding.

[0052] Based on the structure described above, it can be known that the end cover assembly provided by the present application divides the pole into an upper pole 2 and a lower pole 3, and the lower pole 3 is configured to have a convex shape on one side and a groove shape on the other side. Then, after the upper pole 2 and the lower pole 3 are initially assembled, the upper pole 2 and the lower pole 3 can be welded from the groove side, such as by laser welding. Compared with the riveting process in the prior art, the operation is simpler and more convenient, that is, the process is simplified, the process cost is reduced, and the production efficiency is improved. In addition, one side of the lower pole 3 is grooved, which greatly reduces the material cost compared with the solid rivet in the prior art.

[0053] In addition, the upper surface of the upper pole 2 does not need to be riveted, so that the upper surface of the upper pole 2 is smoother and does not require a leveling process, further reducing process costs and improving production efficiency.

[0054] In this embodiment, preferably, Figures 3 to 6 , Figure 8 and Fig.15 As shown, the first protrusion 31 is formed with a first positioning hole 35 communicating with the first groove 32 , and the second protrusion 21 is inserted into the first positioning hole 35 .

[0055] According to the structure described above, the second protrusion 21 is inserted into the first positioning hole 35, thereby playing a role in assembly positioning. In addition, this structure also helps in the subsequent seam welding, so that the upper pole 2 and the lower pole 3 are connected more firmly and stably.

[0056] It should be noted that: it is not limited to the above-mentioned matching structure of the second protrusion 21 and the first positioning hole 35, and one of the following structures can also be adopted, for example: the first structure: a groove is provided on the second protrusion 21, and a protrusion is provided on the first protrusion 31. When the upper pole 2 and the lower pole 3 are assembled, the top of the first protrusion 31 and the bottom of the second protrusion 21 are abutted together, and the protrusion is inserted into the groove, thereby playing the role of assembly positioning and welding;

[0057] The second structure: the second protrusion 21 is formed with a groove, so that the first protrusion 31 is directly inserted into the groove, thereby achieving the functions of assembly positioning and welding;

[0058] The third structure: the first positioning hole 35 is not provided on the first protrusion 31 , and the first protrusion 31 and the second protrusion 21 are directly abutted against each other, and laser penetration welding is performed.

[0059] In this embodiment, preferably, Figure 6 and Fig.15 As shown, the end cover assembly also includes a lower plastic 4 and a current collecting plate 5; wherein the lower pole 3 passes through the current collecting plate 5 and the lower plastic 4 in sequence and then abuts against the upper pole 2 through the pole through hole 12 on the cover plate 1, that is, the current collecting plate 5 and the lower plastic 4 are both provided with through holes, which facilitates the passage of the first protrusion 31 of the lower pole 3, and the through hole provided on the lower plastic 4 and the first protrusion 31 of the lower pole 3 are clearance-matched, which is convenient for installation and avoids squeezing the first protrusion 31 of the lower pole 3 to prevent its deformation;

[0060] The peripheral structure of the lower pole 3 at the first protrusion 31 is a flange 33 , and along the height direction of the cover plate 1 , the flange 33 and the cover plate 1 press the partial structure of the lower plastic 4 and the partial structure of the collecting plate 5 therebetween.

[0061] According to the structure described above, the collecting plate 5 serves to connect the pole ear of the winding core and the lower pole 3, and the lower plastic 4 serves to insulate the lower pole 3 and the cover plate 1. Moreover, part of the structure of the lower plastic 4 and part of the structure of the collecting plate 5 can be pressed by the flange 33 of the lower pole 3 and the cover plate 1, so as to fix the lower plastic 4 and the collecting plate 5.

[0062] In this embodiment, preferably, Figure 6 and Fig.15 As shown, the outer edge of the flange 33 is provided with a step groove 34 with an L-shaped cross section, that is, the step groove 34 runs through the outer side and the top of the flange 33, and the step groove 34 only has a bottom wall and a side wall, and thus the cross section along the height direction parallel to the cover plate 1 is L-shaped;

[0063] The structure of the collecting plate 5 sleeved on the outer periphery of the first protrusion 31 is installed in the step groove 34, and the two are connected by welding.

[0064] According to the structure described above, by setting the step groove 34, the assembly positioning with the collecting plate 5 is achieved, so that the lower pole 3 and the collecting plate 5 are assembled more firmly and stably, and a position for laser welding is provided, and preferably, the bottom wall and side wall of the L-shaped step groove 34 can be used as welding positions.

[0065] Further, preferably, the step groove 34 extends along the outer circumference of the entire flange 33 , presenting a ring groove structure.

[0066] In this embodiment, preferably, Figure 2 and Fig.11 As shown, a positioning groove 14 is formed on one side of the cover plate 1 close to the lower plastic 4 , and a positioning protrusion 41 is formed on one side of the lower plastic 4 close to the cover plate 1 , and the positioning protrusion 41 is installed in the positioning groove 14 .

[0067] According to the structure described above, the assembly and positioning of the two are achieved through the cooperation of the positioning protrusion 41 and the positioning groove 14. Of course, it is not limited to this. The cover plate 1 can also be formed with a positioning protrusion and the lower plastic 4 can be formed with a positioning groove.

[0068] In this embodiment, preferably, Fig.10 As shown, a plurality of ribs 43 are formed on one side of the lower plastic 4 close to the collecting plate 5, wherein at least one rib 43 abuts against one side of the collecting plate 5, and at least another rib 43 abuts against the other side opposite to the collecting plate 5, so as to clamp the collecting plate 5 and the lower plastic 4 together.

[0069] According to the structure described above, it can be known that the current collecting plate 5 is clamped on the inner side of the lower plastic 4 by using a plurality of convex ribs 43, so that the assembly of the two is more stable and firm.

[0070] Further, preferably, the number of the convex ribs 43 is two, and one of the convex ribs 43 is V-shaped, and the other convex rib 43 is cylindrical. It should be noted that the number and shape of the convex ribs 43 are not limited to the above.

[0071] In this embodiment, preferably, Figures 8 to 9 and Fig.15 As shown, the end cap assembly also includes an upper plastic 6, a boss 22 is formed on one side of the upper pole 2 close to the lower pole 3, and the second protrusion 21 passes through the boss 22 and cooperates with the lower pole 3; the upper plastic 6 is sleeved on the boss 22, and the upper plastic 6 is formed with an escape hole for avoiding the second protrusion 21 of the pole. It can be seen that a step installation groove 23 with an L-shaped cross section is naturally formed between the boss 22 and the body 24 of the upper pole 2 (it can be seen that the upper pole 2 includes a body 24, a second protrusion 21 and a boss 22 Both are formed on one side of the body 24 close to the lower pole 3), that is, this L-shaped step mounting groove 23 runs through the outer side and the bottom of the upper pole 2, and the L-shaped step mounting groove 23 has only a top wall and a side wall, and then the cross section along the height direction parallel to the cover plate 1 is L-shaped, and the cross section of the upper plastic 6 along the height direction parallel to the cover plate 1 is also L-shaped, and the top is adapted to the L-shaped step mounting groove 23. It can be seen that the upper surface of the upper plastic 6 is concave, and a through hole is opened in the center;

[0072] The outer side of the cover plate 1 is formed with a sink 11 located just above the pole and connected to the pole through hole 12, that is, the sink 11 is arranged on the top of the pole through hole 12, and the pole through hole 12 runs through the bottom of the sink 11;

[0073] The upper plastic 6 is installed in the sink 11 at the same time. It should be noted here that during the assembly process, the upper plastic 6 can be installed in the sink 11 first, and then the upper pole 2 can be installed, or the upper plastic 6 and the upper pole 2 can be assembled together first, and then the assembly can be installed in the sink 11. The specific selection depends on actual needs.

[0074] According to the structure described above, the upper plastic 6 ensures insulation between the upper pole 2 and the cover 1, and the upper plastic 6 is installed in the sink 11, so that the upper pole 2 wrapped with the upper plastic 6 and the cover 1 are assembled more firmly and stably.

[0075] Further, preferably, Figures 7 to 9 As shown, the main body 24 of the upper pole 2 is square, and correspondingly, the upper plastic 6 is a structure adapted to its shape, and the sink 11 is also a matching square. Of course, it is not limited to this. The sink 11 can also be other shapes, such as pentagons, hexagons and other polygons, or even circles, etc., depending on actual needs.

[0076] Further, preferably, Figure 2 As shown, a compensating protrusion 13 corresponding to the countersunk platform 11 is formed on the inner side of the cover plate 1, and the pole through hole 12 passes through the compensating protrusion 13. This is mainly because the countersunk platform 11 and the pole through hole 12 are sequentially opened in this area on the cover plate 1, resulting in low strength. Therefore, the compensating protrusion 13 is set on the inner side of the cover plate 1 to increase the strength.

[0077] Further, preferably, Fig.11 As shown, the lower plastic 4 is formed with an avoidance groove 42, and the compensating protrusion 13 is installed in the avoidance groove 42, further playing the role of assembly positioning.

[0078] In this embodiment, preferably, Fig.12 and Fig.15 As shown, the end cover assembly further includes a sealing ring 7 , which is installed in the pole through hole 12 and is pressed by the outer wall of the first protrusion 31 and the inner wall of the pole through hole 12 .

[0079] According to the structure described above, the sealing ring 7 plays a sealing role to avoid problems such as electrolyte leakage.

[0080] Further, preferably, Fig.12 As shown, the cross section of the sealing ring 7 along its height direction is T-shaped.

[0081] It should be noted that, in order to ensure the firmness of the assembly of the upper plastic 6 and the sealing ring 7 with the upper pole 2 and the cover plate 1, glue may be applied to the contact positions.

[0082] In this embodiment, preferably, Figure 1 As shown, the end cover assembly further includes an explosion-proof valve (not shown in the figure), which is mounted on the cover plate 1, and preferably, an explosion-proof valve mounting through hole 16 is formed on the cover plate 1, and the explosion-proof valve plays a role of explosion-proof exhaust.

[0083] In this embodiment, preferably, Figure 1 As shown, the cover plate 1 is formed with a liquid injection through hole 15 for liquid injection, and after the liquid injection is completed, a forming nail can be installed for sealing.

[0084] It should be noted that the explosion-proof valve and the injection hole can be simultaneously provided on the cover plate 1 provided in the present application. Of course, it is not limited to this. Only the explosion-proof valve can be provided on the cover plate 1 or only the injection hole can be provided on the cover plate 1. The specific selection depends on actual needs.

[0085] Embodiment 2

[0086] Embodiment 2 of the present application further provides a cylindrical battery, including the end cover assembly described in the above embodiment 1, and thus has all the beneficial technical effects of the end cover assembly, and the same technical features and beneficial effects are not repeated.

[0087] In this embodiment, preferably, the cylindrical battery further includes a winding core and a shell (not shown in the figure); wherein the winding core is arranged in the shell; an opening is formed at at least one end of the shell along its height direction, and the opening is provided with a cover plate assembly, that is, there are three types of assembly structures of the shell and the cover plate 1: the first type: both the top and the bottom of the shell are provided with openings, and each opening is provided with a cover plate assembly; the second type: only the top opening of the shell is provided with a cover plate assembly, and the other side is directly closed or the opening on the other side is provided with other cover plates; the third type: only the bottom opening of the shell is provided with a cover plate assembly, and the other side is directly closed or the opening on the other side is provided with other cover plates, which is selected according to actual needs;

[0088] The current collecting plate 5 of the end cover assembly is connected to the pole ear of the winding core by welding; the cover plate 1 of the cover plate assembly is buckled at the opening of the shell and connected by welding.

[0089] According to the structure described above, the cylindrical battery provided in the present application has a simple structure, is easy to assemble, has high production efficiency, and has low material cost, which helps to improve market competitiveness.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An end cap assembly, characterized in that: include: A cover plate, an upper pole and a lower pole; wherein the upper pole is installed on the outer side of the cover plate; and the lower pole is installed on the inner side of the cover plate; A first protrusion is formed on a side of the lower pole close to the upper pole, and a corresponding first groove is formed on a side of the lower pole away from the upper pole; The cover plate is formed with a pole through hole, the upper pole is formed with a second protrusion, and the second protrusion and the first protrusion both extend into the pole through hole, and the second protrusion and the first protrusion abut against each other and are connected by welding.

2. The end cap assembly according to claim 1, characterized in that: The first protrusion and the second protrusion are plugged together.

3. The end cap assembly according to claim 2, characterized in that: The first protrusion is formed with a first positioning hole communicating with the first groove, and the second protrusion is inserted into the first positioning hole.

4. The end cap assembly according to claim 1, characterized in that: The end cap assembly further includes a lower plastic and a current collecting plate; wherein the lower pole passes through the current collecting plate and the lower plastic in sequence and then abuts against the upper pole through the pole through hole on the cover plate; The peripheral structure of the lower pole located at the first protrusion is a flange, and along the height direction of the cover plate, the flange and the cover plate press the partial structure of the lower plastic and the partial structure of the collecting plate located therebetween.

5. The end cap assembly according to claim 4, characterized in that: The outer edge of the flange is provided with a step groove with an L-shaped cross section, and the structure of the collecting plate sleeved on the outer periphery of the first protrusion is installed in the step groove, and the two are connected by welding.

6. The end cap assembly according to claim 4, characterized in that: A positioning boss is formed on one of the cover plate and the lower plastic, a positioning groove is formed on the other of the cover plate and the lower plastic, and the positioning boss is installed in the positioning groove; and / or A plurality of convex ribs are formed on one side of the lower plastic close to the current collecting plate, wherein at least one of the convex ribs abuts against one side of the current collecting plate, and at least another of the convex ribs abuts against the other opposite side of the current collecting plate, so as to clamp the current collecting plate and the lower plastic together.

7. The end cap assembly according to claim 4, characterized in that: The end cap assembly further includes an upper plastic, a boss is formed on one side of the upper pole close to the lower pole, and the second protrusion passes through the boss and cooperates with the lower pole; the upper plastic sleeve is arranged on the boss, and the upper plastic is formed with an avoidance hole for avoiding the second protrusion of the pole; A sink is formed on the outer side of the cover plate and is located directly above the pole and connected to the pole through hole, and the upper plastic is installed in the sink; a compensation protrusion corresponding to the sink is formed on the inner side of the cover plate, and an avoidance groove is formed on the lower plastic, and the compensation protrusion is installed in the avoidance groove.

8. The end cap assembly according to claim 1, characterized in that: The end cover assembly further includes a sealing ring, which is installed in the pole through hole and is pressed by the outer wall of the first protrusion and the inner wall of the pole through hole.

9. The end cap assembly according to any one of claims 1 to 8, characterized in that: The end cover assembly further comprises an explosion-proof valve, which is mounted on the cover plate, and the cover plate is formed with an exhaust through hole connected to the explosion-proof valve; and / or The cover plate is formed with a liquid injection through hole.

10. A cylindrical battery, characterized in that: It comprises a winding core, a shell and an end cover assembly as claimed in claim 3; wherein the winding core is arranged in the shell; an opening is formed at at least one end of the shell along its height direction, and the opening is provided with the cover plate assembly, the collecting plate of the end cover assembly is connected to the pole ear of the winding core by welding; the cover plate of the cover plate assembly is buckled at the opening of the shell and connected by welding.

Images