Cover plate assembly and cylindrical lithium battery

Abstract

The utility model provides a cover plate assembly and a cylindrical lithium battery. The cover plate assembly comprises a cover plate, an upper plastic part and a pole. A first boss and a first groove which are spaced from each other are arranged on the top face of the cover plate around the first mounting hole in a staggered mode, the first boss, the first groove and the edge of the first mounting hole are spaced by a set distance, and a second boss and a second groove which are spaced from each other are arranged on the bottom face of the body of the upper plastic part around the flange in a staggered mode. The second boss, the second groove and the outer surface of the flange are spaced by a set distance, the first boss, the first groove, the second boss and the second groove are jointly combined to form an anti-torsion structure, and due to the limiting effect of the anti-torsion structure, the upper plastic part and the cover plate cannot rotate relatively, so that the anti-torsion effect is good. The lithium battery comprising the cover plate assembly can prevent the upper plastic part from twisting relative to the cover plate after being used for a long time or under a severe working condition, so that the pole column can be prevented from twisting, and the reliability of the lithium battery can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of lithium-ion batteries, and in particular to a cover plate assembly and a cylindrical lithium battery. Background Art

[0002] In the related art, a pole riveting structure constructed on the top cover can be used as the positive electrode of the cylindrical lithium battery. The pole riveting structure usually includes a pole made of a metal material and an upper plastic part made of a plastic material, wherein the pole is sealed and fixed by the riveting force between the flange of the pole and the upper plastic part. However, since the hardness and strength of the upper plastic part are much smaller than the hardness and strength of the pole, if the pole shakes frequently during long-term use, the upper plastic part will be deformed, and then the upper plastic part will be loosened and twisted. If the pole is twisted together with the upper plastic part, the lithium battery will fail. In particular, for lithium batteries used in harsh working conditions such as power tools, this problem is particularly prominent because the lithium battery will be in a long-term vibration condition. Utility Model Content

[0003] The embodiments of the present application provide a cover plate assembly and a cylindrical lithium battery to at least solve the technical problem that the upper plastic part of the existing cover plate assembly is prone to twisting during long-term use and under harsh working conditions.

[0004] A first aspect of the present application provides a cover plate assembly, including:

[0005] A cover plate, wherein the cover plate is provided with a first mounting hole extending therethrough, and a top surface of the cover plate is staggeredly provided with first bosses and first grooves spaced from each other around the first mounting hole, and the first bosses, the first grooves and the edge of the first mounting hole are spaced a set distance apart;

[0006] An upper plastic part, comprising a body and a flange arranged at the bottom of the body, the upper plastic part is provided with a second mounting hole penetrating the body and the flange, the body abuts against the top surface of the cover plate, the flange is penetrated through the first mounting hole, and the bottom surface of the body is staggeredly provided with second bosses and second grooves spaced from each other around the flange, and the second bosses, the second grooves and the outer surface of the flange are spaced a set distance apart;

[0007] The height of the first boss matches the depth of the second groove, the height of the second boss matches the depth of the first groove, the first bosses are nested in the second grooves one by one, and the second bosses are nested in the first grooves one by one, so as to limit the upper plastic part from rotating relative to the cover.

[0008] The cover plate assembly according to the embodiment of the present application has at least the following beneficial effects:

[0009] In the cover plate assembly of the embodiment of the present application, the first boss and the first groove constructed on the cover plate and the second boss and the second groove constructed on the upper plastic part together constitute an anti-twist structure. Due to the limiting effect of the anti-twist structure, the upper plastic part and the cover plate will not rotate relative to each other. It can be understood that since the first boss and the first groove are spaced apart from each other and are not connected to the first mounting hole, and the second boss and the second groove are spaced apart from each other and are not connected to the flange, the structural strength of the cover plate and the upper plastic part will not be weakened, and the overall nesting depth between the cover plate and the upper plastic part is the sum of the heights of the first boss and the second boss. Therefore, the anti-twist structure combined by the cover plate assembly of the embodiment of the present application is more stable and reliable. After long-term use or use under harsh working conditions, the lithium battery containing the above-mentioned cover plate assembly can avoid the upper plastic part from twisting relative to the cover plate, thereby avoiding the pole from twisting, and improving the reliability of the lithium battery.

[0010] In a possible implementation, the depth of the first groove is H1, the height of the first boss is H2, and H1<H2 is satisfied. The cover plate is made of metal, and by increasing the height of the first boss, the first boss can be nested deeper in the second groove, thereby playing a major anti-twist role.

[0011] In a possible implementation, the thickness of the cover plate is H, and the following ratio is satisfied: H1 / H=30-45%. By properly setting the depth of the first groove, the structural strength of the cover plate is ensured while ensuring that the anti-twist structure works.

[0012] In a possible implementation, a first foolproof structure is disposed on the top surface of the cover plate, and a second foolproof structure that can cooperate with the first foolproof structure is disposed on the bottom surface of the body. The cooperation between the first foolproof structure and the second foolproof structure can improve the efficiency of assembling the upper plastic part and the cover plate.

[0013] In a possible implementation, the first foolproof structure has two locations, and the two first foolproof structures are evenly distributed on both sides of the first mounting hole, and the second foolproof structure has two locations, and the two second foolproof structures are evenly distributed on both sides of the flange. By reasonably designing the number of the first foolproof structure and the second foolproof structure, the efficiency of assembling the upper plastic part and the cover plate can be improved.

[0014] In a possible implementation, the first foolproof structure is a sunken groove extending circumferentially to both sides of the first groove, and the second foolproof structure is a protrusion extending circumferentially to both sides of the second boss; or the first foolproof structure is a protrusion extending circumferentially to both sides of the first boss, and the second foolproof structure is a sunken groove extending circumferentially to both sides of the second groove. The first foolproof structure and the second foolproof structure are designed to be integrated with the first boss, the first groove, the second boss and the second groove, which is easy to process and form, and will not affect the structural strength of the cover plate and the upper plastic part, and will not interfere with other structures.

[0015] In a possible implementation, the first boss and the second boss are both cylindrical, and the first groove and the second groove are both circular. The first boss, the first groove, the second boss, and the second groove are designed to be circular, which is easy to process and form, and the stress concentration of the circular structure is not obvious, which can ensure the safety and reliability of the anti-torsion structure.

[0016] In a possible implementation, a first chamfer is provided between the top surface of the first boss and the outer wall surface, and a second chamfer is provided between the top surface of the second boss and the outer wall surface. By providing chamfer structures on the first boss and the second boss, it is convenient to accurately and quickly assemble the upper plastic part with the cover plate, which can improve the efficiency of assembling the upper plastic part with the cover plate.

[0017] A second aspect of the present application provides a cylindrical lithium battery, comprising a shell and a cover plate assembly according to the first aspect of the present application, wherein the cover plate assembly is disposed on the top of the shell.

[0018] The cylindrical lithium battery according to the embodiment of the present application has at least the following beneficial effects:

[0019] The cylindrical lithium battery of the embodiment of the present application will not twist the plastic part relative to the cover plate when used for a long time or under harsh working conditions, thereby avoiding the twisting of the pole and having the characteristic of high reliability.

[0020] In a possible implementation, the cover plate is integrally formed with the shell. By integrally forming the cover plate with the shell, the process of welding the cover plate with the shell can be omitted, which saves costs and can improve the reliability of the cylindrical lithium battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0022] Figure 1 is a cross-sectional schematic diagram of a cover plate assembly provided in an embodiment of the present application;

[0023] Figure 2 yes Figure 1 A schematic cross-sectional view of the middle cover assembly in an exploded state, wherein the lower plastic part and the sealing ring are omitted;

[0024] Figure 3 yes Figure 1 A schematic diagram of the structure of the middle cover plate of the middle cover plate assembly;

[0025] Figure 4 yes Figure 2 The local schematic diagram of the A in the middle;

[0026] Figure 5 It is a structural schematic diagram of an upper plastic part in a cover assembly provided in an embodiment of the present application.

[0027] Reference numerals:

[0028] 10-cover plate, 11-first mounting hole, 12-first boss, 13-first groove, 14-first fool-proof structure, 121-first chamfered portion;

[0029] 20-upper plastic part, 21-body, 211-second boss, 2111-second chamfered portion, 212-second groove, 22-flange, 23-second mounting hole, 24-second fool-proof structure;

[0030] 30-pole, 31-flange;

[0031] 40-housing;

[0032] 50-lower plastic part;

[0033] 60-Seal ring. DETAILED DESCRIPTION

[0034] Embodiments of the present embodiment are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present embodiment, and should not be construed as limiting the present embodiment.

[0035] In the description of this embodiment, it should be understood that descriptions involving orientation, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this embodiment and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on this embodiment.

[0036] In the description of this embodiment, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed", etc. are understood to exclude the number itself, and "above", "below", "within", etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0037] In the description of this embodiment, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in this embodiment based on the specific content of the technical solution.

[0038] The following combination Figures 1 to 5 The cover plate assembly according to the embodiment of the present application is described in detail.

[0039] like Figure 1 and Figure 2 As shown, the cover plate assembly includes a cover plate 10, an upper plastic part 20 and a pole 30. The cover plate assembly can be used for various types of lithium batteries, such as cylindrical lithium batteries, to form the positive electrode or negative electrode of the lithium battery. The cover plate assembly of the embodiment of the present application, by constructing a first boss 12 and a first groove 13 on the cover plate 10, and constructing a second boss 211 and a second groove 212 on the upper plastic part 20, after the two are assembled, the first boss 12, the first groove 13, the second boss 211 and the second groove 212 are combined to form an anti-twist structure, thereby effectively preventing the upper plastic part 20 from rotating relative to the cover plate 10. Therefore, the lithium battery containing the above-mentioned cover plate assembly can avoid the upper plastic part 20 from twisting relative to the cover plate 10 after long-term use or use under harsh working conditions, and then can avoid the pole 30 from twisting, so as to improve the reliability of the lithium battery.

[0040] The cover plate assembly includes a cover plate 10, which is made of metal. It is understood that the cover plate 10 is the installation base for the upper plastic part 20, the pole 30 and other components, and when the cover plate assembly is assembled into a lithium battery, it is connected to the shell of the lithium battery. Figures 1 to 3As shown, taking the application of the cover plate assembly to a cylindrical lithium battery as an example, the cylindrical lithium battery includes a cylindrical shell 40, and the cover plate 10 is located on the top of the shell 40 as the top cover of the cylindrical lithium battery, and the cover plate 10 is integrally formed with the shell 40. In this way, the process of separately welding the cover plate 10 on the shell 40 can be omitted, which can save processes and costs. Of course, it is not limited to this. The cover plate 10 can also be an independent component such as a metal sheet, which is subsequently connected to the shell 40 through a welding process. Further, the cover plate 10 is the top cover of the cylindrical lithium battery, and therefore, the cover plate 10 is circular as a whole, but it is not limited to this. For example, the shape of the cover plate 10 can also be rectangular for square lithium batteries.

[0041] like Figures 1 to 3 As shown, it can be understood that the cover plate 10 has a top surface and a bottom surface relative to each other. For a lithium battery, the top surface of the cover plate 10 is located outside the lithium battery, and the bottom surface of the cover plate 10 is located inside the lithium battery. The cover plate 10 is provided with a first mounting hole 11 that penetrates through the cover plate 10, that is, the first mounting hole 11 penetrates the cover plate 10 in the thickness direction (the up and down direction in the figure), so that the first mounting hole 11 connects the top surface and the bottom surface of the cover plate 10, and the first mounting hole 11 is used for the upper plastic part 20 to penetrate therein, so as to achieve insulation isolation of the pole 30 passing through the upper plastic part 20.

[0042] It is understandable that if Figure 3 As shown, the top surface of the cover plate 10 is staggered with first bosses 12 and first grooves 13 spaced from each other around the first mounting hole 11, and the first bosses 12 and the first grooves 13 are spaced from the edge of the first mounting hole 11 by a set distance L1. It can be understood that the first bosses 12 and the first grooves 13 spaced from each other are staggered around the first mounting hole 11 on the top surface of the cover plate 10, so that when the upper plastic part 20 is assembled from the top to the bottom in the direction close to the top surface of the cover plate 10, the first bosses 12 and the first grooves 13 can be assembled with the second grooves 212 and the second bosses 211 constructed on the upper plastic part 20 to be described below, and finally combined into an anti-twist structure.

[0043] It is understandable that the staggered arrangement described here means that along the circumferential direction surrounding the first mounting hole 11, the first boss 12 and the first groove 13 are staggered in an alternating manner, that is, a first groove 13 is arranged between two first bosses 12, and correspondingly, a first boss 12 is arranged between two first grooves 13. In this way, firstly, in the circumferential direction surrounding the first mounting hole 11, staggered first bosses 12 and first grooves 13 are formed, so that the anti-twist structure formed after being nested with the second groove 212 and the second boss 211 is evenly distributed along the 360-degree range of the circumference, the force is relatively balanced, and the anti-twist structure is safe and reliable. In addition, the first boss 12 and the first groove 13 are simultaneously arranged on the cover plate 10, so that the nesting depth between it and the upper plastic part 20 is the sum of the height of the first boss 12 and the depth of the first groove 13. Therefore, while ensuring the anti-twist effect, the depth of the first groove 13 can be reduced as much as possible to avoid excessive weakening of the structural strength of the cover plate 10.

[0044] Furthermore, adjacent first bosses 12 and first grooves 13 are spaced apart from each other, that is, two adjacent first bosses 12 and first grooves 13 are not connected, and the two are separated by the wall of the cover plate 10. Thus, the multiple first bosses 12 and multiple first grooves 13 constructed on the cover plate 10 are dispersed in the circumferential direction of the first mounting hole 11, so as to avoid excessive weakening of the structural strength of the cover plate 10. Similarly, the first bosses 12 and the first grooves 13 are also spaced apart from the edge of the first mounting hole 11 by a set distance, so as to avoid weakening the structural strength at the edge of the first mounting hole 11, and to ensure that the inner wall surface of the first mounting hole 11 is intact, so as to improve the fitting effect with the upper plastic part 20.

[0045] like Figure 3 As shown, combined with Figure 5It can be understood that the anti-twist structure described in this embodiment is composed of the first boss 12 and the first groove 13 constructed on the cover plate 10, and the second boss 211 and the second groove 212 constructed on the upper plastic part 20, which are connected together. Therefore, the shape, size and number of the first boss 12 and the second groove 212 match, and the shape, size and number of the first groove 13 and the second boss 211 match. Specifically, the height of the first boss 12 matches the depth of the second groove 212, so that the first boss 12 can be completely nested in the second groove 212, and accordingly, the height of the second boss 211 matches the depth of the first groove 13, so that the second boss 211 can be completely nested in the first groove 13, so that the bottom surface of the upper plastic part 20 can be well fitted with the top surface of the cover plate 10. Taking the number of the first bosses 12, the first grooves 13, the second bosses 211 and the second grooves 212 as an example, for example, the number of the first bosses 12 and the number of the first grooves 13 are both four, and correspondingly, the number of the second bosses 211 and the number of the second grooves 212 on the matching upper plastic part 20 are also four.

[0046] It is understandable that, since the outer contours of the first mounting hole 11 and the upper plastic part 20 are both circular, it is impossible to quickly determine whether the two have the correct assembly angle. During the assembly process, it is easy for the second boss 211 to be exactly opposite to the first boss 12, resulting in the inability to efficiently assemble the cover plate 10 and the upper plastic part 20. Therefore, in order to improve the assembly efficiency of the cover plate 10 and the upper plastic part 20, in some embodiments, such as Figure 3 As shown, the top surface of the cover plate 10 is provided with a first foolproof structure 14, and the first foolproof structure 14 can cooperate with the second foolproof structure 24 formed on the upper plastic part 20 to be introduced below. In this way, during the assembly process, as long as the first foolproof structure 14 and the second foolproof structure 24 are ensured to correspond to each other, for example, to be located in the same direction, the upper plastic part 20 can be accurately assembled to the cover plate 10, which is very convenient.

[0047] Furthermore, in order to reduce the adjustment workload during assembly, in some embodiments, there are two first foolproof structures 14, and the two first foolproof structures 14 are evenly distributed on both sides of the first mounting hole 11. In this way, the two first foolproof structures 14 are evenly distributed on both sides of the first mounting hole 11, that is, the two first foolproof structures 14 are arranged at 180°, which ensures that the assembly can be completed when the cover plate 10 and the upper plastic part 20 to be assembled are at the 0° or 180° position, which can improve the efficiency of assembly. It can be understood that by reasonably designing the number of the first foolproof structures 14, the efficiency of assembling the cover plate 10 and the upper plastic part 20 can be improved.

[0048] Furthermore, in some embodiments, the first fool-proof structure 14 is a sunken groove extending circumferentially to both sides of the first groove 13. Of course, it is not limited thereto, for example, the first fool-proof structure 14 can also be a protrusion extending circumferentially to both sides of the first boss 12. It can be understood that by designing the first fool-proof structure 14 to be integrated with the first boss 12 or the first groove 13, it is easy to process and form, and will not affect the structural strength of the cover plate 10, and will not interfere with other structures.

[0049] like Figure 3 As shown, in some embodiments, the first boss 12 is cylindrical and the first groove 13 is circular. The first boss 12 and the first groove 13 are designed to be circular, which is easy to process and form, and the stress concentration of the circular structure is not obvious, which can ensure the safety and reliability of the anti-torsion structure.

[0050] Furthermore, a first chamfered portion 121 is provided between the top surface and the outer wall surface of the first boss 12. The first chamfered portion 121 can guide the first boss 12 when it is nested into the second groove 212, so as to facilitate the accurate and rapid assembly of the upper plastic part 20 with the cover plate 10, thereby improving the efficiency of the assembly of the upper plastic part 20 with the cover plate 10.

[0051] As mentioned above, the cover plate 10 is made of metal, which has higher strength. Figure 4 As shown, in some embodiments, the depth of the first groove 13 is H1, and the height of the first boss 12 is H2, which satisfies: H1<H2. Since the first boss 12 and the second groove 212 are nested with each other, and the first groove 13 and the second boss 211 are nested with each other, accordingly, it can be understood that the height of the first boss 12 is higher than the height of the second boss 211. By increasing the height of the first boss 12, the depth of the nesting of the first boss 12 and the second groove 212 can be made deeper, so that the first boss 12 plays a major role in preventing torsion.

[0052] like Figure 4 As shown, in some embodiments, the thickness of the cover plate 10 is H, and the following is satisfied: H1 / H=30-45%. It is understandable that if H1 is too large, the structural strength of the cover plate 10 will be weakened; conversely, if H1 is too small, the anti-twist effect cannot be guaranteed. Therefore, by reasonably setting the depth of the first groove 13, the structural strength of the cover plate 10 is guaranteed while ensuring that the anti-twist structure works.

[0053] It can be understood that the cover plate 10 assembly includes an upper plastic part 20, which serves to insulate and isolate the pole 30 from the cover plate 10. In this embodiment, the upper plastic part 20 is made of plastic, and is an independent component formed by, for example, an injection molding process, connected to the cover plate 10 through a certain assembly movement, and the riveting force generated by the pole 30 is pressed against the top surface of the cover plate 10, and finally forms a cover plate 10 assembly with the cover plate 10, the pole 30, etc.

[0054] like Figure 5 As shown, combined with Figure 1 and Figure 2 In some embodiments, the upper plastic part 20 includes a body 21 and a flange 22 arranged at the bottom of the body 21. The upper plastic part 20 is provided with a second mounting hole 23 that penetrates the body 21 and the flange 22. That is, the second mounting hole 23 penetrates the upper plastic part 20 along the thickness direction (the up and down direction in the figure), so that the second mounting hole 23 connects the top surface of the body 21 and the bottom surface of the flange 22. The second mounting hole 23 is used for the pole 30 to pass therethrough, so as to achieve insulation isolation between the cover plate 10 and the pole 30.

[0055] Specifically, the outer contour size of the body 21 is larger than the diameter of the first mounting hole 11, while the outer contour size of the flange 22 is adapted to the inner diameter of the first mounting hole 11, so that when the upper plastic part 20 is assembled from top to bottom in the direction close to the top surface of the cover plate 10, the flange 22 can penetrate into the first mounting hole 11, and its outer surface can fit well with the inner wall surface of the first mounting hole 11, while the body 21 can be limited by the top surface of the cover plate 10, thereby preventing the upper plastic part 20 from falling into and passing through the first mounting hole 11 as a whole. It can be understood that in the assembled cover plate assembly, the body 21 is subjected to the riveting force of the pole 30 and abuts against the top surface of the cover plate 10.

[0056] Further, it can be understood that the second bosses 211 and the second grooves 212 are arranged alternately around the flange 22 on the bottom surface of the body, and the second bosses 211 and the second grooves 212 are spaced apart from each other by a set distance from the outer surface of the flange 22. It can be understood that the second bosses 211 and the second grooves 212 are arranged alternately around the first mounting hole 11 on the bottom surface of the body 21, so that when the plastic part 20 is assembled from top to bottom in a direction close to the top surface of the cover plate 10, the second bosses 211 and the second grooves 212 can be assembled in a nested manner with the first grooves 13 and the first bosses 12 constructed on the cover plate 10, and finally combined into an anti-twist structure.

[0057] It is understandable that the staggered arrangement described here means that along the circumferential direction of the surrounding flange 22, the second boss 211 and the second groove 212 are staggered in an alternating manner, that is, a second groove 212 is arranged between two second bosses 211, and correspondingly, a second boss 211 is arranged between two second grooves 212. In this way, firstly, in the circumferential direction of the surrounding flange 22, staggered second bosses 211 and second grooves 212 are formed, so that the anti-torsion structure formed by the nesting of the first groove 13 and the first boss 12 is evenly distributed along the 360° range of the circumference, the force is relatively balanced, and the anti-torsion structure is safe and reliable. In addition, the second boss 211 and the second groove 212 are simultaneously arranged on the body 21, so that the nesting depth between it and the cover plate 10 is the sum of the height of the second boss 211 and the depth of the second groove 212. Therefore, while ensuring the anti-torsion effect, the depth of the groove structure can be reduced as much as possible to avoid excessive weakening of the structural strength of the cover plate 10.

[0058] Furthermore, adjacent second bosses 211 and second grooves 212 are spaced apart from each other, that is, two adjacent second bosses 211 and second grooves 212 are not connected, and the two are separated by the wall of the body 21. Thus, the plurality of second bosses 211 and the plurality of second grooves 212 constructed on the body 21 are dispersed in the circumferential direction around the flange 22, so as to avoid excessive weakening of the structural strength of the body 21. Similarly, the second bosses 211 and the second grooves 212 are also spaced apart from the outer surface of the flange 22 by a set distance L2, so as to avoid weakening the structural strength of the flange 22.

[0059] like Figure 5 As shown, combined with Figure 3 It can be understood that the anti-twist structure described in this embodiment is composed of the first boss 12 and the first groove 13 constructed on the cover plate 10, and the second boss 211 and the second groove 212 constructed on the upper plastic part 20, which are connected together. Therefore, the shape, size and number of the first boss 12 and the second groove 212 match, and the shape, size and number of the first groove 13 and the second boss 211 match. Specifically, the height of the first boss 12 matches the depth of the second groove 212, so that the first boss 12 can be completely nested in the second groove 212, and accordingly, the height of the second boss 211 matches the depth of the first groove 13, so that the second boss 211 can be completely nested in the first groove 13, so that the bottom surface of the body 21 can be well fitted with the top surface of the cover plate 10. Taking the number of the first bosses 12, the first grooves 13, the second bosses 211 and the second grooves 212 as an example, for example, the number of the first bosses 12 and the number of the first grooves 13 are both four, and correspondingly, the number of the second bosses 211 and the number of the second grooves 212 on the matching upper plastic part 20 are also four.

[0060] like Figure 5 As shown, in some embodiments, the bottom surface of the body 21 is provided with a second foolproof structure 24, and the second foolproof structure 24 can cooperate with the first foolproof structure 14 as described above. In this way, during the assembly process, as long as the first foolproof structure 14 and the second foolproof structure 24 correspond to each other, for example, are located in the same direction, the upper plastic part can be accurately assembled to the cover plate, which is very convenient.

[0061] Furthermore, in order to reduce the adjustment workload during assembly, in some embodiments, there are two second foolproof structures 24, and the two second foolproof structures 24 are evenly distributed on both sides of the flange 22. In this way, the two second foolproof structures 24 are evenly distributed on both sides of the flange 22, that is, the two second foolproof structures 24 are arranged at 180°, which ensures that the assembly can be completed when the cover plate 10 and the upper plastic part 20 to be assembled are at 0° or 180°, which can improve the efficiency of assembly. It can be understood that by reasonably designing the number of second foolproof structures 24, the efficiency of assembling the upper plastic part and the cover plate can be improved.

[0062] Furthermore, in some embodiments, the second fool-proof structure 24 is a protrusion extending circumferentially to both sides of the second boss 211. Of course, it is not limited thereto, for example, the second fool-proof structure 24 can also be a sink extending circumferentially to both sides of the second groove 212. It is understandable that by designing the second fool-proof structure 24 to be integrated with the second boss 211 or the second groove 212, it is easy to process and shape, and will not affect the structural strength of the body 21, and will not interfere with other structures.

[0063] like Figure 5 As shown, in some embodiments, the second boss 211 is cylindrical and the second groove 212 is circular. The second boss 211 and the second groove 212 are designed to be circular, which is easy to process and form, and the stress concentration of the circular structure is not obvious, which can ensure the safety and reliability of the anti-torsion structure.

[0064] Furthermore, a second chamfered portion 2111 is provided between the top surface and the outer wall surface of the second boss 211. The second chamfered portion 2111 can guide the second boss 211 when it is nested into the first groove 13, so as to facilitate the accurate and rapid assembly of the upper plastic part 20 with the cover plate 10, thereby improving the efficiency of the assembly of the upper plastic part 20 with the cover plate 10.

[0065] It is understood that the cover assembly includes a pole 30. When assembled into a lithium battery, the pole 30 is electrically connected to the internal winding pole group of the lithium battery to serve as an electrical contact of the lithium battery for connecting external electrical equipment to the lithium battery. It is understood that the material of the pole 30 is a metal such as aluminum, which has good electrical conductivity and is also easy to press the upper plastic part 20 to the top surface of the cover 10 through a riveting process. It is understood that through the riveting process, the pole 30 forms a flange 31 on the top surface, and the flange 31 is pressed on the top of the body 21 of the upper plastic part 20.

[0066] Of course, reference Figure 1 In addition to the cover plate 10, upper plastic part 20 and pole 30 mentioned above, the cover plate assembly also includes a lower plastic part 50, a sealing ring 60 and other components located on one side of the bottom surface of the cover plate 10. Since these components are irrelevant to the purpose of this application, they are not introduced in this application.

[0067] The present application also provides a cylindrical lithium battery, which includes the cover plate assembly of the above embodiment. Due to the cover plate assembly of the above embodiment, when the cylindrical lithium battery of this embodiment is used for a long time or in harsh working conditions, the upper plastic part 20 will not be twisted relative to the cover plate 10, thereby preventing the pole 30 from twisting, and has the characteristic of high reliability.

[0068] like Figure 1 and Figure 2 As shown, in some embodiments, the cover plate 10 is the top cover of a cylindrical lithium battery, and the cylindrical lithium battery includes a cylindrical shell 40 and the cover plate 10 located on the top of the shell 40, and the shell 40 and the cover plate 10 are integrally formed. In this way, the process of welding the cover plate assembly on the shell 40 can be omitted, which can save processes and costs.

[0069] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present implementation. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0070] Although examples of the present embodiment have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present embodiment, and the scope of the present embodiment is defined by the claims and their equivalents.

Claims

1. A cover plate assembly, characterized in that: include: A cover plate (10), the cover plate (10) being provided with a first mounting hole (11) extending therethrough, the top surface of the cover plate (10) being provided with first bosses (12) and first grooves (13) spaced from each other in an alternating manner around the first mounting hole (11), and the first bosses (12), the first grooves (13) being spaced from the edge of the first mounting hole (11) by a set distance; An upper plastic part (20) comprises a body (21) and a flange (22) arranged at the bottom of the body (21); the upper plastic part (20) is provided with a second mounting hole (23) penetrating the body (21) and the flange (22); the body (21) abuts against the top surface of the cover plate (10); the flange (22) is penetrated through the first mounting hole (11); the bottom surface of the body (21) is alternately provided with second bosses (211) and second grooves (212) spaced from each other around the flange (22); and the second bosses (211), the second grooves (212) and the outer surface of the flange (22) are spaced from each other by a set distance; The height of the first boss (12) matches the depth of the second groove (212), the height of the second boss (211) matches the depth of the first groove (13), each of the first bosses (12) is nested in each of the second grooves (212) in a one-to-one correspondence, and each of the second bosses (211) is nested in each of the first grooves (13) in a one-to-one correspondence, so as to limit the upper plastic part (20) from rotating relative to the cover plate (10).

2. The cover plate assembly according to claim 1, characterized in that: The depth of the first groove (13) is H1, and the height of the first boss (12) is H2, which satisfies: H1<H2.

3. The cover plate assembly according to claim 2, characterized in that: The thickness of the cover plate (10) is H, and the following relation is satisfied: H1 / H=30-45%.

4. The cover plate assembly according to claim 1, characterized in that: The top surface of the cover plate (10) is provided with a first fool-proof structure (14), and the bottom surface of the body (21) is provided with a second fool-proof structure (24) capable of cooperating with the first fool-proof structure (14).

5. The cover plate assembly according to claim 4, characterized in that: The first fool-proofing structures (14) are provided at two locations, and the two first fool-proofing structures (14) are evenly distributed on both sides of the first mounting hole (11); the second fool-proofing structures (24) are provided at two locations, and the two second fool-proofing structures (24) are evenly distributed on both sides of the flange (22).

6. The cover plate assembly according to claim 4, characterized in that: The first fool-proofing structure (14) is a recessed groove extending along the circumferential direction to both sides of the first groove (13), and the second fool-proofing structure (24) is a protrusion extending along the circumferential direction to both sides of the second boss (211); or The first fool-proofing structure (14) is a protrusion extending along the circumferential direction toward both sides of the first boss (12), and the second fool-proofing structure (24) is a recessed groove extending along the circumferential direction toward both sides of the second groove (212).

7. The cover plate assembly according to claim 1, characterized in that: The first boss (12) and the second boss (211) are both cylindrical, and the first groove (13) and the second groove (212) are both circular hole-shaped.

8. The cover plate assembly according to claim 7, characterized in that: A first chamfered portion (121) is provided between the top surface of the first boss (12) and the outer wall surface, and a second chamfered portion (2111) is provided between the top surface of the second boss (211) and the outer wall surface.

9. A cylindrical lithium battery, characterized in that: It comprises a shell (40) and a cover plate assembly according to any one of claims 1 to 8, wherein the cover plate assembly is arranged on the top of the shell (40).

10. The cylindrical lithium battery according to claim 9, characterized in that: The cover plate (10) and the shell (40) are integrally formed.

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