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 convex part and a first concave part are arranged on a cover plate, a second convex part, a second concave part, a third convex part and a third concave part are arranged on an upper plastic part, a fourth convex part and a fourth concave part are arranged on a pole, and after the cover plate, the upper plastic part and the pole are assembled, the first convex part and the first concave part are nested, and the second convex part and the second concave part are nested; the third convex part is nested with the third concave part, the fourth convex part is nested with the fourth concave part, and the third convex part and the third concave part are combined together to form an anti-torsion structure, so that when the lithium battery comprising the cover plate assembly is used for a long time or under a severe working condition, the upper plastic part and the pole are not easy to twist because the torsion strength among the cover plate, the upper plastic part and the pole is relatively high, and the reliability of the lithium battery is improved. Therefore, the reliability and the safety 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, during long-term use, the pole frequently shakes so that the riveting fails, and the pole twists relative to the upper plastic part, resulting in the failure of the lithium battery. Furthermore, the shaking of the pole will also cause the upper plastic part to deform, which in turn causes the upper plastic part to loosen and twist. If the pole twists 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 pole and the upper plastic part in the existing cover plate assembly are 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] The cover plate is provided with a first mounting hole penetrating therethrough, wherein a hole wall of the first mounting hole is circumferentially configured with alternating first convex portions and first concave portions;

[0006] An upper plastic part is inserted into the first mounting hole, the upper plastic part is provided with a penetrating second mounting hole, the outer wall of the upper plastic part is circumferentially configured with alternating second convex parts and second concave parts, and the hole wall of the second mounting hole is circumferentially configured with alternating third convex parts and third concave parts;

[0007] A pole, which is inserted into the second mounting hole, and the outer wall of the pole is configured with alternating fourth convex parts and fourth concave parts along the circumferential direction;

[0008] Among them, each of the first protrusions is nested in each of the second recesses one by one, and each of the second protrusions is nested in each of the first recesses one by one, so as to limit the upper plastic part from rotating relative to the cover plate, and each of the third protrusions is nested in each of the fourth recesses one by one, and each of the fourth protrusions is nested in each of the third recesses one by one, so as to limit the pole from rotating relative to the upper plastic part.

[0009] The cover plate assembly according to the embodiment of the present application has at least the following beneficial effects:

[0010] In the cover plate assembly of the embodiment of the present application, the first convex portion and the first concave portion constructed on the cover plate and the second convex portion and the second concave portion constructed on the upper plastic part together constitute an anti-twist structure. Due to the limiting effect of the anti-twist structure, relative rotation is not easy to occur between the upper plastic part and the cover plate. At the same time, the third convex portion and the third concave portion constructed on the upper plastic part and the fourth convex portion and the fourth concave portion constructed on the pole together constitute an anti-twist structure. Due to the limiting effect of the anti-twist structure, relative rotation is not easy to occur between the pole and the upper plastic part. Therefore, when the lithium battery including the above-mentioned cover plate assembly is used for a long time or is used under harsh working conditions, the upper plastic part and the pole are not easy to twist due to the strong torsional strength between the cover plate, the upper plastic part and the pole, thereby improving the reliability and safety of the lithium battery.

[0011] In a possible embodiment, the hole wall of the first mounting hole is circumferentially configured with a ridge at the top, and the outer wall of the upper plastic part is circumferentially configured with a positioning groove that matches the ridge, and the ridge is covered in the positioning groove to limit the upper plastic part from moving in the axial direction of the first mounting hole. By providing the positioning groove and the ridge covered therein, the upper plastic part can be limited from moving in the axial direction of the first mounting hole, and the upper plastic part can be prevented from moving in the axial direction of the first mounting hole.

[0012] In a possible implementation, the ridge is squeezed into the positioning groove by elastic deformation caused by the upper plastic part being pressed by the ridge under downward pressure. This assembly method is quick and convenient, and can greatly improve the efficiency of the connection between the ridge and the positioning groove.

[0013] In a possible implementation, the downward pressure is provided by riveting the pole. By using the riveting process of the pole to provide downward pressure, no additional tools and processes are required, and the cover plate and the upper plastic part are directly connected by riveting technology, which is very convenient.

[0014] In a possible implementation, the ridge is only formed at each of the first concave portions, and the positioning groove is only formed at each of the second convex portions. By properly arranging the positions of the ridge and the positioning groove, the manufacturing difficulty and cost of the upper plastic part and the cover plate can be reduced, and the impact on the strength of the upper plastic part can be reduced.

[0015] In a possible implementation, the thickness of the cover plate is H, the height of the ridge is H1, and the following is satisfied: H1 / H=20% to 50%. By properly designing the height of the ridge, the upper plastic part can be effectively locked axially, and the assembly processability and connection stability of the cover plate and the upper plastic part can also be improved.

[0016] In a possible implementation, the top surface of the convex ridge is arranged to be inclined toward the inside of the first mounting hole along the radial direction. By arranging the top surface of the convex ridge to be inclined toward the inside of the first mounting hole along the radial direction, the flange can be guided and then smoothly compressed and deformed toward the center direction of the first mounting hole, thereby improving the efficiency and quality of assembly.

[0017] In a possible implementation, the inclination angle of the top surface of the ridge is α, which satisfies 20°≤α≤50°. By properly designing the inclination angle of the top surface of the ridge, the assembly efficiency is improved on the one hand, and the limiting effect is ensured on the other hand.

[0018] In a possible implementation, the second convex portion, the second concave portion, the third convex portion, and the third concave portion are formed by the wall portion of the upper plastic part extending alternately in a radial direction and a circumferential direction of the second mounting hole. By arranging the wall portion of the upper plastic part to extend alternately in a circumferential direction and a radial direction to form the second convex portion, the second concave portion, the third convex portion, and the third concave portion, the upper plastic part has a compact and simple structure, is easy to process, and has the advantages of being light in weight and easy to assemble.

[0019] A second aspect of the present application provides a cylindrical lithium battery, comprising a cover plate assembly according to the first aspect.

[0020] The cylindrical lithium battery according to the embodiment of the present application has at least the following beneficial effects:

[0021] The cylindrical lithium battery of the embodiment of the present application is not easily twisted when used for a long time or under harsh working conditions because the torsional strength between the cover plate, the upper plastic part and the pole is strong, so the cylindrical lithium battery has the characteristics of high reliability and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] 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.

[0023] Figure 1 is a cross-sectional schematic diagram of a cover plate assembly provided in an embodiment of the present application;

[0024] Figure 2 yes Figure 1 An exploded schematic diagram of a cover plate, an upper plastic part and a pole in a cover plate assembly;

[0025] Figure 3 yes Figure 1 A cross-sectional schematic diagram of a cover plate in a cover plate assembly;

[0026] Figure 4 yes Figure 3 The local schematic diagram of the A in the middle;

[0027] Figure 5 yes Figure 1 A schematic diagram of the structure of the top of the upper plastic part in the cover assembly;

[0028] Figure 6 yes Figure 1 A schematic diagram of the structure of the bottom of the upper plastic part in the cover assembly;

[0029] Figure 7 yes Figure 1 Schematic diagram of the structure of the pole in the cover assembly.

[0030] Reference numerals:

[0031] 10-cover plate, 11-first mounting hole, 111-first convex portion, 112-first concave portion, 113-convex ridge;

[0032] 20-upper plastic part, 21-flange, 211-second convex part, 212-second concave part, 213-positioning groove, 21a-first wall part, 21b-second wall part, 21c-third wall part, 22-second mounting hole, 221-third convex part, 222-third concave part, 23-body;

[0033] 30-pole, 31-connecting portion, 311-fourth convex portion, 312-fourth concave portion, 313-gap, 32-end portion, 321-flanging, 33-supporting portion;

[0034] 40-housing;

[0035] 50-lower plastic part;

[0036] 60-Seal ring. DETAILED DESCRIPTION

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] The following combination Figures 1 to 7 The cover plate assembly according to the embodiment of the present application is described in detail.

[0042] like Figure 1 and Figure 2As shown, the cover assembly includes a cover 10, an upper plastic part 20 and a pole 30. The cover 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 assembly of the embodiment of the present application is constructed by constructing a first protrusion 111 and a first recess 112 on the cover 10, constructing a second protrusion 211, a second recess 212, a third protrusion 221, and a third recess 222 on the upper plastic part 20, and constructing a fourth protrusion 311 and a fourth recess 312 on the pole 30. After the three are assembled, the first protrusion 111 is nested with the first recess 112, the second protrusion 211 is nested with the second recess 212, the third protrusion 221 is nested with the fourth recess 312, and the fourth protrusion 311 is nested with the third recess 222. The two recesses 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. The third convex portion 221, the third recess 222, the fourth convex portion 311 and the fourth recess 312 are combined to form another anti-twist structure, thereby effectively preventing the pole 30 from rotating relative to the upper plastic part 20. Therefore, when the lithium battery including the above-mentioned cover plate assembly is used for a long time or used under harsh working conditions, the upper plastic part 20 and the pole 30 are not easy to twist due to the strong torsional strength between the cover plate 10, the upper plastic part 20 and the pole 30, thereby improving the reliability and safety of the lithium battery.

[0043] It is understood that 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, the cover plate 10 is connected to the housing 40 of the lithium battery. Figure 1 and Figure 2 As 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.

[0044] like Figure 1 and Figure 3As 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.

[0045] like Figure 2 and Figure 3 As shown, the hole wall of the cover plate 10 is constructed with alternating first protrusions 111 and first recesses 112 along the circumferential direction. It can be understood that the alternation of the first protrusions 111 and the first recesses 112 described here means that a first recess 112 is provided between two first protrusions 111, and correspondingly, a first protrusion 111 is provided between two first recesses 112. In this way, alternating first protrusions 111 and first recesses 112 are formed in the circumferential direction of the hole wall of the first mounting hole 11, so that in the anti-twist structure, the first protrusion 111, the first recess 112, the second recess 212 and the second protrusion 211 are evenly distributed in the circumferential range of 360°, the force is relatively balanced, and the anti-twist structure is safe and reliable.

[0046] Specifically, the first convex portion 111 is formed by the hole wall of the first mounting hole 11 protruding in the direction toward the center of the first mounting hole 11, and the first concave portion 112 is defined between two adjacent first convex portions 111. In this case, all surfaces of the first convex portions 111 and all surfaces of the first concave portions 112 together constitute the hole wall of the first mounting hole 11, that is, the first convex portion 111 and the first concave portion 112 also penetrate the cover plate 10 as a whole, and are both connected to the top surface and the bottom surface of the cover plate 10. Of course, it is not limited to this, and the first convex portion 111 and the first concave portion 112 can also be formed in any suitable manner.

[0047] It can be understood that, therefore, when the upper plastic part 20 is operated to make an assembly movement from top to bottom in a direction close to the top surface of the cover plate 10, each first protrusion 111 can be embedded in each second recess 212 on the upper plastic part 20, and each second protrusion 211 can be embedded in each first recess 112, that is, the nesting movement of the first protrusion 111 and the second recess 212, and the nesting movement of the second protrusion 211 and the first recess 112 are synchronously achieved as the upper plastic part 20 is operated to make an assembly movement from top to bottom in a direction close to the top surface of the cover plate 10. Therefore, after the upper plastic part 20 and the cover plate 10 are assembled, each first protrusion 111 is nested in each second recess 212 in a one-to-one correspondence, and each second protrusion 211 is nested in each first recess 112 in a one-to-one correspondence. The first protrusion 111, the first recess 112, the second protrusion 211 and the second recess 212 together form an anti-twist structure to limit the upper plastic part 20 from rotating relative to the cover plate 10.

[0048] like Figure 2 As shown, it can be understood that the shape, size and number of the first convex portion 111 and the second concave portion 212 match, and the shape, size and number of the first concave portion 112 and the second convex portion 211 match. Take the shapes of the first convex portion 111, the first concave portion 112, the second convex portion 211 and the second concave portion 212 as an example for explanation, for example, the projections of the first convex portion 111, the first concave portion 112, the second convex portion 211 and the second concave portion 212 on the bottom surface of the cover plate 10 are all fan-shaped; take the number of the first convex portion 111, the first concave portion 112, the second convex portion 211 and the second concave portion 212 as an example for explanation, for example, the number of the first convex portion 111 and the number of the first concave portion 112 are both four, and accordingly, the number of the second convex portions 211 and the number of the second concave portions 212 on the upper plastic part 20 that matches them are also four.

[0049] It is understandable that during the long-term use of the lithium battery or when used under harsh working conditions, as the riveting force of the pole 30 weakens, the upper plastic part 20 may not only be twisted relative to the cover plate 10, but may also be displaced up and down relative to the cover plate 10. Therefore, in some embodiments, the hole wall of the first mounting hole 11 is circumferentially configured with a ridge 113, and the outer wall of the flange 21 is circumferentially configured with a positioning groove 213 that cooperates with the ridge 113, and the ridge 113 is enclosed in the positioning groove 213 to limit the upper plastic part 20 from moving in the axial direction of the first mounting hole 11.

[0050] In some embodiments, Figure 3 and Figure 4 As shown, combined with Figure 2The convex rib 113 is formed by the hole wall of the first mounting hole 11 protruding along the center direction of the first mounting hole 11, and the positioning groove 213 is formed by the outer wall of the flange 21 concave along the center direction of the second mounting hole 22. In this way, the cover plate 10 and the upper plastic part 20 can be snap-fitted, and then an axial constraint is formed between the two to limit the displacement of the upper plastic part 20 along the axial direction of the first mounting hole 11. For example, the convex rib 113 can be elastically deformed by the flange 21 under the downward pressure and the convex rib 113, and squeezed into the positioning groove 213. Among them, the ridge 113 formed on the cover plate 10 plays a limiting function, and the flange 21 formed on the upper plastic part 20 plays a locking function. The flange 21 is deformed during the assembly process. When the ridge 113 is inserted into the positioning groove 213, the flange 21 returns to its original position to be locked with the cover plate 10 and provide a holding force. This assembly method is quick and convenient, and can greatly improve the efficiency of the connection between the ridge 113 and the positioning groove 213.

[0051] Specifically, the upper plastic part 20 is assembled from the top side of the cover plate 10, and during this process, its flange 21 is inserted into the first mounting hole 11. Therefore, when the upper plastic part 20 is operated to perform an assembly movement from top to bottom in a direction close to the top surface of the cover plate 10, after the flange 21 contacts the ridge 113, the necessary downward pressure is continuously applied to the upper plastic part 20, which causes the flange 21 to deform and continue to move downward. When the deformation of the flange 21 reaches a certain degree, the ridge 113 is inserted into the positioning groove 213. At this time, since the flange 21 is no longer squeezed by the ridge 113, it returns to its original position and its outer wall surface fits well with the hole wall of the first mounting hole 11.

[0052] It is understandable that after the pole 30 is inserted into the second mounting hole 22, a riveting process is finally performed to connect the cover plate 10, the upper plastic part 20 and other components through the pole 30. In some embodiments, the purpose of snapping the ridge 113 into the positioning groove 213 is achieved by applying downward pressure when riveting the pole 30. That is, the flange 21 is now positioned at the top of the ridge 113, and after the pole 30 is inserted into the second mounting hole 22, the pole 30 is riveted, so that the upper plastic part 20 is subjected to the downward pressure applied by the pole 30, so that the ridge 113 is snapped into the positioning groove 213, thereby realizing a snap connection with the cover plate 10 synchronously. In this way, the snap connection between the cover plate 10 and the upper plastic part 20 is directly realized by the riveting process without adding additional tools and processes, which is very convenient.

[0053] It should be noted that the surfaces of the aforementioned first protrusion 111 and the first recess 112 together constitute the hole wall of the first mounting hole 11. Therefore, in this embodiment, the rib 113 is arranged on the hole wall of the first mounting hole 11, which also means that the rib 113 is arranged on the surface of the first protrusion 111 and the first recess 112. It can be understood that the positions of the rib 113 and the positioning groove 213 are arranged corresponding to each other, and the rib 113 and the positioning groove 213 can be arranged in sections or completely within a 360° circumference, which is not limited here. For the purpose of facilitating processing and not affecting the structural strength of the flange 21, as Figure 2 and Figure 3 As shown, in some embodiments, the convex rib 113 is only configured at each first concave portion 112, and the positioning groove 213 is only configured at each second convex portion 211. In this way, the convex rib 113 will not invade the central area of ​​the first mounting hole 11, and the manufacturing difficulty and cost can also be reduced. Similarly, when the positioning groove 213 is only configured at each second convex portion 211, the structural strength of the flange 21 will not be weakened, and the structure is simple and easy to process.

[0054] The rib 113 is disposed at the top of the hole wall of the first mounting hole 11, and the top surface of the rib 113 is smoothly transitionally connected to the top surface of the cover plate 10. Correspondingly, the position of the positioning groove 213 is also disposed at a corresponding height on the flange 21. In this way, the flange 21 can be initially positioned by the rib 113 without additional assembly action, so that the subsequent riveting process can provide downward pressure to snap the rib 113 into the positioning groove 213, which is very convenient. Of course, it is not limited to this, and the height of the rib 113 and the positioning groove 213 can be flexibly adjusted, for example, located in the middle of the first mounting hole 11. Further, as Figure 4 As shown, in some embodiments, the thickness of the cover plate 10 is H, the height of the ridge 113 is H1, and the following is satisfied: H1 / H=20% to 50%. It is understandable that if the height of the ridge 113 is too small, it is difficult to machine a guide slope at the top of the ridge 113, which is not conducive to the flange 21 being clamped into the first mounting hole 11, and the ridge 113 itself is also easily damaged and thus ineffective; on the contrary, if the height of the ridge 113 is too large, the effective fitting height between the hole wall of the first mounting hole 11 and the outer wall surface of the flange 21 is too small, and the connection between the two is unstable. When the riveting force of the pole 30 is weakened, the upper plastic part 20 is prone to shifting up and down and shaking. Therefore, by reasonably designing the height of the ridge 113, it can effectively achieve the purpose of axial locking with the upper plastic part 20, and can also improve the assembly processability and connection stability of the two.

[0055] Furthermore, in some embodiments, the top surface of the rib 113 is arranged to be inclined in the radial direction toward the inside of the first mounting hole 11. By arranging the top surface of the rib 113 to be inclined in the radial direction toward the inside of the first mounting hole 11, the flange 21 can be guided, so that when the downward pressure is applied to the flange 21, it is smoothly compressed and deformed toward the center direction of the first mounting hole 11, so as to improve the efficiency and quality of assembly.

[0056] Furthermore, in some embodiments, the inclination angle of the top surface of the rib 113 is α, which satisfies 20°≤α≤50°. It is understandable that if the inclination angle of the top surface of the rib 113 is too small, the guiding effect on the assembly of the flange 21 is not obvious, which increases the difficulty of the rib 113 being inserted into the positioning groove 213, and even damages the rib 113 or the flange 21; on the contrary, if the inclination angle of the top surface of the rib 113 is too large, it is difficult to ensure the locking effect of the rib 113 in the positioning groove 213, and then the upper plastic part 20 cannot be effectively limited in the axial direction. Therefore, by reasonably designing the inclination angle of the top surface of the rib 113, the assembly efficiency is improved on the one hand, and the limiting effect is ensured on the other hand.

[0057] It can be understood that the cover plate assembly includes an upper plastic part 20, and the upper plastic part 20 plays the role of insulating and isolating 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 is pressed against the top surface of the cover plate 10 by the riveting force generated by the pole 30, and finally forms a cover plate assembly with the cover plate 10, the pole 30, etc.

[0058] like Figure 5 and Figure 6 As shown, in some embodiments, the upper plastic part 20 includes a flange 21 and a body 23 located on the top of the flange 21, and the upper plastic part 20 is provided with a second mounting hole 22 that penetrates the body 23 and the flange 21, that is, the second mounting hole 22 penetrates the upper plastic part 20 along the thickness direction (the up and down direction in the figure), so that the second mounting hole 22 connects the top surface of the body 23 and the bottom surface of the flange 21, and the second mounting hole 22 is used for the pole 30 to pass therethrough, so as to achieve insulation isolation between the cover plate 10 and the pole 30.

[0059] Specifically, the outer contour size of the body 23 is larger than the diameter of the first mounting hole 11, while the outer contour size of the flange 21 matches 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 21 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 23 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 23 is pressed against the top surface of the cover plate 10 by the riveting force of the pole 30.

[0060] like Figure 5 and Figure 6 As shown, the outer wall of the flange 21 is circumferentially configured with alternating second protrusions 211 and second recesses 212, and the hole wall of the second mounting hole 22 is circumferentially configured with alternating third protrusions 221 and third recesses 222. It can be understood that the alternation of the second protrusions 211 and the second recesses 212 described herein means that a second recess 212 is provided between two second protrusions 211, and correspondingly, a second protrusion 211 is provided between two second recesses 212, and the same applies to the third protrusions 221 and the third recesses 222. In this way, in the anti-twist structure formed by the nesting of the second convex portion 211, the second concave portion 212, the first concave portion 112, and the first convex portion 111, the second convex portion 211, the second concave portion 212, the first concave portion 112, and the first convex portion 111 are evenly distributed in a circumferential range of 360°, the force is relatively balanced, and the anti-twist structure is safe and reliable. At the same time, in the anti-twist structure formed by the nesting of the third convex portion 221, the third concave portion 222, the fourth convex portion 311, and the fourth concave portion 312, the third convex portion 221, the third concave portion 222, the fourth convex portion 311, and the fourth concave portion 312 are evenly distributed in a circumferential range of 360°, the force is relatively balanced, and the anti-twist structure is safe and reliable.

[0061] In some embodiments, the second convex portion 211, the second concave portion 212, the third convex portion 221 and the third concave portion 222 are formed by the wall portion of the flange 21 extending alternately in a radial direction and a circumferential direction of the second mounting hole 22. Specifically, the wall portion of the flange 21 includes a first wall portion 21a located in the outer ring and extending in the circumferential direction, a second wall portion 21b located in the inner ring and extending in the circumferential direction, and a third wall portion 21c extending in the radial direction, and the third wall portion 21c connects the first wall portion 21a and the second wall portion 21b. Among them, the first wall portion 21a and the outer walls of the third wall portions 21c on both sides together constitute the second convex portion 211, the second wall portion 21b and the outer walls of the third wall portions 21c on both sides together constitute the second concave portion 212, and the first wall portion 21a and the inner walls of the third wall portions 21c on both sides together constitute the third concave portion 222, and the second wall portion 21b and the inner walls of the third wall portions 21c on both sides together constitute the third convex portion 221. In this case, the surfaces of all second protrusions 211 and all second recesses 212 together constitute the outer wall surface of the flange 21, and the surfaces of all third protrusions 221 and all third recesses 222 together constitute the inner surface of the flange 21, that is, the hole wall of the second mounting hole 22.

[0062] It can be understood that the second convex portion 211, the second concave portion 212, the third convex portion 221 and the third concave portion 222 are formed by the wall portion of the flange 21 in a radial direction and a circumferential direction of the second mounting hole 22 in an alternately zigzag manner, and the structure is compact and simple. These structures can be directly molded by the upper plastic part 20 through integral injection molding, which is very convenient and has the advantages of light weight and easy assembly. Of course, it is not limited to this, and the second convex portion 211, the second concave portion 212, the third convex portion 221 and the third concave portion 222 can be any other suitable structure.

[0063] It can be understood that, when the upper plastic part 20 is operated to make an assembly movement from top to bottom in a direction close to the top surface of the cover plate 10, each second protrusion 211 can be embedded in each first recess 112 of the cover plate 10, and at the same time, each first protrusion 111 of the cover plate 10 can be embedded in each second recess 212, that is, the nesting movement of the first protrusion 111 and the second recess 212, and the nesting movement of the second protrusion 211 and the first recess 112 are synchronously achieved as the upper plastic part 20 is operated to make an assembly movement from top to bottom in a direction close to the top surface of the cover plate 10. Therefore, when the assembly is completed, each first protrusion 111 is nested in each second recess 212 one by one, and each second protrusion 211 is nested in each first recess 112 one by one. The first protrusion 111, the first recess 112, the second protrusion 211 and the second recess 212 together form an anti-twist structure to limit the upper plastic part 20 from rotating relative to the cover 10.

[0064] At the same time, it can be understood that when the operating pole 30 is assembled in the direction from bottom to top in the direction close to the bottom surface of the flange 21, the third protrusion 221 can be embedded in each fourth recess 312 on the pole 30, and each fourth protrusion 311 on the pole 30 can be embedded in each third recess 222, that is, the nesting movement of the third protrusion 221 and the fourth recess 312, and the nesting movement of the fourth protrusion 311 and the third recess 222 are synchronously achieved as the operating pole 30 is assembled in the direction from bottom to top in the direction close to the bottom surface of the flange 21. Therefore, when the assembly is completed, each third protrusion 221 is nested in each fourth recess 312 in a one-to-one correspondence, and each fourth protrusion 311 is nested in each third recess 222 in a one-to-one correspondence. The third protrusion 221, the third recess 222, the fourth protrusion 311 and the fourth recess 312 together form an anti-twist structure to limit the rotation of the pole 30 relative to the upper plastic part 20.

[0065] like Figure 5 and Figure 6 As shown, it can be understood that the second convex portion 211 matches the shape, size and number of the first concave portion 112, and the second concave portion 212 matches the shape, size and number of the first convex portion 111. Take the shapes of the first convex portion 111, the first concave portion 112, the second convex portion 211 and the second concave portion 212 as an example for explanation, for example, the projections of the first convex portion 111, the first concave portion 112, the second convex portion 211 and the second concave portion 212 on the bottom surface of the cover plate 10 are all fan-shaped; take the number of the first convex portion 111, the first concave portion 112, the second convex portion 211 and the second concave portion 212 as an example for explanation, for example, the number of the first convex portion 111 and the number of the first concave portion 112 are both four, and accordingly, the number of the second convex portions 211 and the number of the second concave portions 212 on the upper plastic part 20 that matches them are also four. The third convex portion 221 , the third concave portion 222 , the fourth convex portion 311 and the fourth concave portion 312 are similar and are not described in detail herein.

[0066] In some embodiments, the hole wall of the first mounting hole 11 is circumferentially configured with a ridge 113, and the outer wall of the flange 21 is circumferentially configured with a positioning groove 213 that matches the ridge 113. The ridge 113 is covered in the positioning groove 213 to limit the upper plastic part 20 from moving in the axial direction of the first mounting hole 11. The positioning groove 213 is formed by the second convex portion 211 of the flange 21 being concave in the direction toward the center of the second mounting hole 22. Specifically, the positioning groove 213 is formed at the top of the second convex portion 211, that is, the top of the first wall portion 21a. The positioning groove 213 is arranged at this position for easy processing and assembly, and is convenient for the snap connection between the positioning groove 213 and the ridge 113.

[0067] 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 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.

[0068] like Figure 7 As shown, the pole 30 includes a connecting portion 31 located in the middle, a terminal portion 32 located at the top end of the connecting portion 31, and a supporting portion 33 located at the bottom end of the connecting portion 31. The connecting portion 31 is inserted into the second mounting hole 22, the supporting portion 33 is located at the bottom of the cover plate 10, and the terminal portion 32 is exposed at the top of the body 23 of the upper plastic part 20, and is used for electrical connection with external equipment. Further, the terminal portion 32 includes a flange 321 located at the periphery, and the flange 321 is a deformed portion generated by riveting the pole 30, thereby pressing the body 23 against the top surface of the cover plate 10.

[0069] Among them, the outer wall of the connecting portion 31 is constructed with alternating fourth convex portions 311 and fourth concave portions 312 along the circumferential direction. It can be understood that the alternation of the fourth convex portions 311 and the fourth concave portions 312 described here means that a fourth concave portion 312 is arranged between two fourth convex portions 311, and correspondingly, a fourth convex portion 311 is arranged between two fourth concave portions 312. In this way, the anti-torsion structure composed of the fourth convex portion 311, the fourth concave portion 312 and the aforementioned third concave portion 222, the third convex portion 221 is evenly distributed within the circumferential range, the force is relatively balanced, and the anti-torsion structure is safe and reliable.

[0070] Specifically, the fourth protrusion 311 is formed by the outer wall of the connecting portion 31 protruding in a direction away from the center of the second mounting hole 22, and a fourth recess 312 is defined between two adjacent fourth protrusions 311. Of course, it is not limited thereto, and the fourth protrusion 311 and the fourth recess 312 can also be formed in any suitable manner.

[0071] When the operating pole 30 is assembled from bottom to top in a direction close to the bottom surface of the flange 21, each fourth protrusion 311 can be embedded in each third recess 222, and each third protrusion 221 can also be embedded in each fourth recess 312, that is, the nesting movement of the fourth protrusion 311 and the third recess 222, and the nesting movement of the third protrusion 221 and the fourth recess 312 are synchronously realized as the operating pole 30 is assembled from bottom to top in a direction close to the bottom surface of the flange 21. Therefore, when the assembly is completed, each third protrusion 221 is nested in each fourth recess 312 one by one, and each fourth protrusion 311 is nested in each third recess 222 one by one, and the third protrusion 221, the third recess 222, the fourth protrusion 311 and the fourth recess 312 together constitute an anti-twist structure to limit the pole 30 from rotating relative to the upper plastic part 20.

[0072] like Figure 7 As shown, combined with Figure 2 It can be understood that the shape, size and number of the fourth convex portion 311 match those of the third concave portion 222, and the shape, size and number of the fourth concave portion 312 match those of the third convex portion 221. Take the shapes of the fourth convex portion 311, the fourth concave portion 312, the third convex portion 221 and the third concave portion 222 as an example for explanation, for example, the projections of the fourth convex portion 311, the fourth concave portion 312, the third convex portion 221 and the third concave portion 222 on the bottom surface of the cover plate 10 are all fan-shaped; take the number of the fourth convex portion 311, the fourth concave portion 312, the third convex portion 221 and the third concave portion 222 as an example for explanation, for example, the number of the fourth convex portion 311 and the number of the fourth concave portion 312 are both four, and correspondingly, the number of the third concave portions 222 and the number of the third convex portions 221 on the upper plastic part 20 that match them are also four.

[0073] Further, in some embodiments, a gap 313 is provided between the bottom surface of the fourth protrusion 311 and the top surface of the support portion 33, and the gap 313 is used to accommodate the sealing ring 60 described below. It is understandable that the height of the gap 313 can be set to be the same as the thickness of the sealing ring 60, so that the bottom surface of the fourth protrusion 311 is coplanar with the bottom surface of the cover plate 10, thereby improving the sealing effect.

[0074] Of course, if Figure 1 As shown, the cover assembly includes, in addition to the cover 10 , the upper plastic part 20 and the pole 30 mentioned above, a lower plastic part 50 and a sealing ring 60 located on one side of the bottom surface of the cover 10 .

[0075] 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 and the pole 30 are not easily twisted due to the strong torsional strength between the cover plate 10, the upper plastic part 20 and the pole 30, so that the cylindrical lithium battery has the characteristics of high reliability and safety.

[0076] like Figures 1 to 3 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.

[0077] 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.

[0078] 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) is provided with a penetrating first mounting hole (11), wherein a hole wall of the first mounting hole (11) is configured with alternating first convex portions (111) and first concave portions (112) along a circumferential direction; An upper plastic part (20) is inserted into the first mounting hole (11), the upper plastic part (20) is provided with a penetrating second mounting hole (22), the outer wall of the upper plastic part (20) is circumferentially configured with alternating second convex parts (211) and second concave parts (212), and the hole wall of the second mounting hole (22) is circumferentially configured with alternating third convex parts (221) and third concave parts (222); A pole (30) is inserted into the second mounting hole (22), and an outer wall of the pole (30) is configured with alternating fourth protrusions (311) and fourth recesses (312) along a circumferential direction; Each of the first protrusions (111) is nested in each of the second recesses (212) in a one-to-one correspondence, and each of the second protrusions (211) is nested in each of the first recesses (112) in a one-to-one correspondence, so as to limit the upper plastic part (20) from rotating relative to the cover plate (10); each of the third protrusions (221) is nested in each of the fourth recesses (312) in a one-to-one correspondence, and each of the fourth protrusions (311) is nested in each of the third recesses (222) in a one-to-one correspondence, so as to limit the pole (30) from rotating relative to the upper plastic part (20).

2. The cover plate assembly according to claim 1, characterized in that: The hole wall of the first mounting hole (11) is circumferentially configured with a ridge (113), and the outer wall of the upper plastic part (20) is circumferentially configured with a positioning groove (213) that matches the ridge (113), and the ridge (113) is covered in the positioning groove (213) to limit the upper plastic part (20) from moving in the axial direction of the first mounting hole (11).

3. The cover plate assembly according to claim 2, characterized in that: The convex ridge (113) is elastically deformed and squeezed into the positioning groove (213) by the upper plastic part (20) under the downward pressure and the convex ridge (113).

4. The cover plate assembly according to claim 3, characterized in that: The downward force is provided by a riveting action on the pole (30).

5. The cover plate assembly according to any one of claims 2 to 4, characterized in that: The convex ridge (113) is only constructed at each of the first concave portions (112), and the positioning groove (213) is only constructed at each of the second convex portions (211).

6. The cover plate assembly according to any one of claims 2 to 4, characterized in that: The thickness of the cover plate is H, and the height of the ridge (113) is H1, which satisfies: H1 / H=20% to 50%.

7. The cover plate assembly according to any one of claims 2 to 4, characterized in that: The top surface of the convex ridge (113) is arranged to be inclined toward the inside of the first mounting hole (11) along the radial direction.

8. The cover plate assembly according to claim 7, characterized in that: The inclination angle of the top surface of the convex ridge (113) is α, which satisfies 20°≤α≤50°.

9. The cover plate assembly according to any one of claims 1 to 4, characterized in that: The second convex portion (211), the second concave portion (212), the third convex portion (221) and the third concave portion (222) are formed by the wall portion of the upper plastic part (20) extending alternately in a radial direction and a circumferential direction of the second mounting hole (22) in a zigzag manner.

10. A cylindrical lithium battery, characterized in that: The invention comprises the cover plate assembly according to any one of claims 1 to 9.

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