Top cover assembly and battery

Abstract

The invention discloses a top cover assembly and a battery. The top cover assembly comprises a top cover and a pole component. A first surface and a second surface are arranged in the Z direction of the top cover, a connecting hole is formed in the top cover, and the connecting hole extends in the Z direction of the top cover; the pole component is arranged on the first surface and covers the connecting hole, the pole component comprises a welding piece, and the welding piece is welded and fixed on the top cover. According to the top cover assembly and the battery, the problems of high production cost and high use risk of the top cover assembly of the battery in the prior art can be solved.

Description

Technical Field

[0001] The present application relates to the technical field of charging and discharging devices, and in particular to a top cover assembly and a battery. Background Art

[0002] Lithium-ion batteries do not contain toxic substances and are green, high-energy chemical power sources. Lithium-ion batteries have the advantages of light weight, high specific energy, long cycle life, wide allowable operating temperature range, and good low-temperature performance. They have been widely used in industries such as digital electronic products and electric vehicles.

[0003] Lithium-ion batteries usually include an electrode assembly, a shell that contains the electrode assembly, and a top cover assembly fixed to the top of the shell. At present, the top cover assembly of lithium-ion batteries is usually processed and assembled between the top cover and the pole parts using a riveting process. The production cost of the top cover assembly processed by the riveting process is relatively high, and after a period of use, the top cover assembly is at risk of loosening, which can easily have an adverse effect on the service life of the battery. Summary of the invention

[0004] The main purpose of the present application is to provide a top cover assembly and a battery to solve the problems of high production cost and high use risk of the top cover assembly of the battery in the prior art.

[0005] According to one aspect of the present application, a top cover assembly is provided, comprising:

[0006] A top cover, wherein the top cover is provided with a first surface and a second surface in the Z direction, and the top cover is provided with a connecting hole, and the connecting hole extends along the Z direction of the top cover; and

[0007] A pole component is arranged on the first surface and covers the connection hole. The pole component includes a welding piece, and the welding piece is welded and fixed on the top cover.

[0008] Furthermore, a welding hole is provided on the top cover, and the welding hole is provided through the top cover along the Z direction, and the welding piece is inserted into the welding hole and is welded to the top cover.

[0009] Further, the welding piece includes an annular body and a plurality of welding segments, the plurality of welding segments are arranged at intervals along the circumference of the annular body, and each of the welding segments extends along the Z direction of the top cover;

[0010] There are a plurality of welding holes, and the plurality of welding holes are arranged at intervals along the outer circumference of the connecting hole, and a plurality of welding segments are inserted into the plurality of welding holes one by one and are welded and fixed to the top cover.

[0011] Furthermore, the welding hole is a through hole or a blind hole. When the welding hole is a through hole, the bottom end surface of the welding section is flush with or not flush with the bottom surface of the second surface.

[0012] Further, the welding piece and the top cover are welded on the second surface to form a welding mark, and a starting end of the welding mark deviates from an outer edge of the welding piece or is located at an outer edge of the welding piece.

[0013] Furthermore, the starting end of the weld mark deviates from the outer edge of the weld part, and the depth of the starting end of the weld mark is not greater than the depth of the weld mark at the edge of the weld part.

[0014] Further, the depth of the weld mark along the Z direction of the top cover is H, and the thickness of the top cover in the Z direction is D, wherein 0.1D≤H≤0.6D.

[0015] Furthermore, the width of the weld mark along the X direction of the top cover is L, wherein 0.5 mm≤L≤2 mm, and 0.5 mm≤H≤2 mm.

[0016] Furthermore, the top cover assembly also includes:

[0017] A sealing ring is provided between the first surface and the pole component, the sealing ring is arranged around the outer circumference of the connecting hole, and along the radial direction of the connecting hole, the sealing ring is located on one side of the welding section close to the center of the connecting hole.

[0018] Furthermore, the pole component includes a pole and an upper plastic, the upper plastic is arranged on the outer periphery of the pole, and the welding section is fixedly connected to the upper plastic and protrudes from the end surface of the upper plastic close to the first surface.

[0019] Furthermore, the minimum distance between the inner side of the upper plastic close to the pole, the side of the upper plastic away from the top cover, and the outer side of the upper plastic and the welding part is not less than a first predetermined value.

[0020] Furthermore, the first predetermined value is greater than or equal to 0.3 mm.

[0021] Furthermore, a projection of the pole in the axial direction of the connecting hole at least partially overlaps with a projection of the sealing ring in the axial direction of the connecting hole.

[0022] Further, the pole includes a limiting portion, which is arranged between the annular body and the first surface, and a projection of the annular body in the axial direction of the connecting hole and a projection of the limiting portion in the axial direction of the connecting hole at least partially overlap.

[0023] Furthermore, an annular sink is provided on the top cover, the annular sink is located at the outer periphery of the connecting hole, and the sealing ring is provided on the annular sink.

[0024] Furthermore, the welding hole is located at the outer periphery of the annular sink, and the side wall of the welding hole is connected to or spaced a predetermined distance from the side wall of the annular sink.

[0025] Furthermore, there is a clearance fit between the welding piece and the welding hole.

[0026] Furthermore, the gap between the welding piece and the connecting hole is no greater than 0.2 mm.

[0027] Furthermore, the pole includes a main body and an outer flange located on the outer periphery of the main body, the sealing ring is arranged on a side of the outer flange close to the first surface, and the distance H2 from the outer side surface of the outer flange to the welding part is greater than the distance H3 from the outer edge of the sealing ring to the welding part.

[0028] Further, along the Z direction, the top surface of the outer flange is flush with or higher than the portion of the top surface of the sealing ring that is not pressed by the outer flange.

[0029] Furthermore, an annular sink is provided on the top cover, the annular sink is located at the outer periphery of the connecting hole, and the sealing ring is provided on the annular sink.

[0030] Furthermore, the welding hole is located at the outer periphery of the annular sink, and the side wall of the welding hole is connected to or spaced a predetermined distance from the side wall of the annular sink.

[0031] Furthermore, along the radial direction of the connecting hole, the side wall surface of the welding hole close to the connecting hole is flush or not flush with the side wall surface at the corresponding position of the annular sink. 24. The top cover assembly according to claim 10, further comprising a lower plastic, wherein the lower plastic comprises:

[0032] A first plastic part, the first plastic part comprises an annular plastic body and an annular protrusion arranged on the annular plastic body, the annular plastic body is located in the connecting hole, and the annular protrusion is arranged between the pole component and the top cover;

[0033] A second plastic part, the second plastic part is disposed on the second surface and connected to the annular plastic body as a whole;

[0034] The second plastic part completely covers the welding hole, or a avoidance hole is provided at a position of the second plastic part corresponding to the welding hole.

[0035] Furthermore, the thickness D1 of the upper plastic, the thickness D2 of the annular protrusion, and the thickness D3 of the sealing ring compressed by the pole satisfy the relationship: 3≥(D1-D3) / (D2+D3)≥0.5.

[0036] Furthermore, the thickness D3 of the sealing ring compressed by the pole is ≥0.3 mm.

[0037] Furthermore, the welding holes are elongated holes, a plurality of the welding holes are spaced apart along the circumference of the first ring shape, and the sum of the lengths of the plurality of welding holes accounts for 0.15 to 0.75 of the circumference of the first ring shape.

[0038] Furthermore, the pole component includes a positive pole component and a negative pole component, the pole component includes a pole, the pole of the positive pole component is an aluminum pole, the pole of the negative pole component is a copper-aluminum pole, and the bottom of the copper-aluminum pole is an aluminum base.

[0039] On the other hand, the present application also provides a battery, comprising the above-mentioned top cover assembly.

[0040] In the present application, when the top cover assembly in the present application is actually produced, the connection hole is first processed on the top cover, and then the pole component is obtained by injection molding. Finally, the pole component is installed on the first surface of the top cover and the connection hole is covered. The pole component can be welded and fixed to the first surface of the top cover by welding with the top cover by welding. Compared with the prior art method of installing the pole component on the top cover by riveting process, the pole component and the top cover of the top cover assembly in the present application are connected by welding process, which can save riveting parts, lower production cost, and is not easy to get loose during use. It can improve the safety and reliability of the top cover assembly in the present application and the battery with the top cover assembly, and can improve the service life of the top cover assembly to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0042] Figure 1 A three-dimensional structural diagram of a top cover assembly disclosed in an embodiment of the present application;

[0043] Figure 2 An exploded view of a top cover assembly disclosed in an embodiment of the present application;

[0044] Figure 3 for Figure 2 A magnified view of the M region in FIG.

[0045] Figure 4 A three-dimensional structural diagram of a pole component disclosed in an embodiment of the present application;

[0046] Figure 5 A three-dimensional structural diagram of a welding part disclosed in an embodiment of the present application;

[0047] Figure 6 for Figure 2 A magnified view of the N region in FIG.

[0048] Figure 7 A top view of the top cover assembly disclosed in an embodiment of the present application;

[0049] Figure 8 for Figure 7 AA section view in;

[0050] Fig. 9 for Figure 8 Amplification of the II region Figure 1 ;

[0051] Fig.10 for Figure 8 Amplification of the II region Figure 2 ;

[0052] Fig.11 for Figure 8 A magnified view of region III in FIG.

[0053] Fig.12 Another top cover assembly disclosed in the embodiment of the present application is Figure 7 The cross-sectional view at the AA position in FIG.

[0054] Fig.13 A top view of the top cover disclosed in the embodiment of the present application;

[0055] Fig.14 for Fig.13 A magnified view of region I in FIG.

[0056] Fig.15 Another top cover disclosed in the embodiment of the present application is Fig.13 An enlarged view of the I region in FIG.

[0057] Fig.16 Another top cover disclosed in the embodiment of the present application is Fig.13 An enlarged view of the I region in FIG.

[0058] The above drawings include the following reference numerals:

[0059] 10. Top cover; 11. Connection hole; 12. Welding hole; 121. First side wall; 13. Annular sink; 131. Second side wall; 101. First surface; 102. Second surface; 20. Pole component; 21. Pole; 211. Main body; 212. Outer flange; 2121. First side surface; 22. Upper plastic; 2201. Inner side surface; 2202. Outer side surface; 2203. Upper side surface; 23. Welding piece; 231. Annular main body; 232. Welding section; 30. Sealing ring; 31. Second side surface; 40. Lower plastic; 41. First plastic part; 411. Annular plastic body; 412. Annular convexity; 42. Second plastic part; 421. Avoidance hole; 50. Welding stamp; 80. Positive and negative pole identification. DETAILED DESCRIPTION

[0060] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0061] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0062] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0063] See also Figures 1 to 4 As shown, according to an embodiment of the present application, a top cover assembly is provided, and the top cover assembly is particularly a top cover assembly of a battery. The top cover assembly in this embodiment includes a top cover 10 and a pole component 20.

[0064] The top cover 10 is provided with a first surface 101 and a second surface 102 in the Z direction, and a connection hole 11 is provided on the top cover 10, and the connection hole 11 extends along the Z direction of the top cover 10; the pole component 20 is provided on the first surface 101 of the top cover 10 and covers the connection hole 11, and a welding piece 23 is provided on the pole component 20, and the welding piece 23 is welded and fixed on the top cover 10. It can be understood that the first surface 101 of the top cover 10 mentioned here refers to the top surface of the top cover assembly when it is used, especially refers to the side of the top cover 10 facing away from the internal space of the battery.

[0065] When the top cover assembly in the present embodiment is actually produced, the connection hole 11 is first processed on the top cover 10, and then the pole component 20 is obtained by injection molding. Finally, the pole component 20 is installed on the first surface 101 of the top cover 10 and the connection hole 11 is covered. The pole component 20 can be welded and fixed to the top cover 10 by welding the welding piece 23 to the top cover 10. Compared with the prior art method of installing the pole component 20 on the top cover 10 by riveting, the pole component 20 of the top cover assembly in the present application is connected to the top cover 10 by welding, which can save riveting parts, reduce production costs, and is not prone to loosening during use. It can improve the safety and reliability of the top cover assembly in the present embodiment and the battery having the top cover assembly, and can improve the service life of the top cover assembly to a certain extent. See Figures 2 to 16 As shown, in order to further improve the structural stability of the top cover assembly in this embodiment, in this embodiment, the welding holes 12 on the top cover 10 are set to be multiple, and the multiple welding holes 12 are arranged at intervals along the outer circumference of the connecting hole 11; correspondingly, the welding piece 23 on the pole component 20 includes an annular body 231 and multiple welding segments 232, and the multiple welding segments 232 are arranged at intervals along the circumference of the annular body 231, and the multiple welding segments 232 are inserted into the multiple welding holes 12 one by one and welded to the top cover 10. Exemplarily, the welding holes 12 and welding segments 232 in this embodiment can be set to two, three, four or more than four. Figures 13 to 15 FIG. 2 shows a case where there are four welding holes 12. It is understood that the annular body 231 in this embodiment includes a circular annular body, a square annular body, or other polygonal or special-shaped annular bodies. Figure 5 In the figure, the annular body 231 is a square annular body. In actual processing, the annular body 231 and the welding section 232 can be integrally formed or welded together after being processed separately. As long as it is other deformation methods under the concept of the present application, they are all within the protection scope of the present application.

[0066] In the present application, welding is performed by cooperating with a plurality of welding holes 12 and a plurality of welding segments 232, so that the connection strength between the pole component 20 and the top cover 10 can be improved. Optionally, the welding hole 12 in the present embodiment is a long strip hole, and in the circumferential direction of the welding hole 12, the sum of the lengths of the plurality of welding holes 12 accounts for 0.15 to 0.75 of the circumferential length of the corresponding part. For example, 0.15, 0.3, 0.45, 0.6 or 0.75. It should be noted that the "circumferential length of the corresponding part" in the present embodiment refers to "taking the side of the plurality of welding holes 12 close to the connecting hole 11 as a reference to form an annular structure similar to the connecting hole 11, and the circumference of the annular structure is the circumferential length of the corresponding part described here. For details, please refer to Fig.13 The circumference of the annular structure A shown in FIG. 1 is shown in FIG. 1 . When the sum of the lengths of the plurality of welding holes 12 accounts for less than 0.15 of the circumferential length of the corresponding portion, it is not convenient to stably weld the pole body 211 to the top cover 10. When the sum of the lengths of the welding holes 12 accounts for more than 0.75 of the circumferential length of the corresponding portion, the welding holes 12 are relatively dense, and it is not convenient to ensure the structural strength of the top cover 10 around the connecting hole 11.

[0067] The top cover 10 in this embodiment can be set in a rectangular shape, a square shape, a round shape, an elliptical shape or other special-shaped structures. The top cover 10 can be selected and designed according to the shape of the battery. Figure 1 The top cover 10 is shown in the figure when it is set in a rectangular shape. In order to facilitate welding of the welding piece 23, a welding hole 12 is provided on the top cover 10, and the welding hole 12 is set through the top cover 10 in the Z direction, that is, the welding hole 12 is a through hole, and the welding piece 23 is inserted in the welding hole 12 and welded to the top cover 10. Such a setting facilitates the use of laser penetration welding to weld the top cover 10 and the welding piece 23 together, and the structure is stable and has high strength. Of course, in other embodiments of the present application, the welding hole 12 can also be set as a blind hole, as long as it is other deformation methods under the concept of the present application, it is within the scope of protection of the present application. When the welding hole 12 is a through hole, the bottom end face of the welding section 232 is flush or uneven with the bottom face of the second surface 102. It can be understood that the bottom end face of the welding section 232 in the present application refers to the end face of the welding piece 23 inserted into the welding hole 12 and close to the inside of the battery, and the second surface 102 of the top cover 10 refers to the face of the top cover 10 close to the inside of the battery. In the present application, by making the bottom end surface of the welding section 232 flush with the bottom surface of the top cover 10, it is easier to inject the lower plastic 40 into the bottom of the top cover 10; when the bottom end surface of the welding section 232 is not flush with the bottom surface of the top cover 10, the contact area between the lower plastic 40 and the top cover 10 or the welding part 23 can be increased. After the lower plastic 40 is injected, the connection stability between the structures of the entire top cover assembly is better, and the lower plastic 40 is not easy to peel off.

[0068] See also Figures 4 to 12 As shown, the welding piece 23 and the top cover 10 are welded at the end of the welding hole 12 close to the second surface 102 to form a weld mark 50, and the starting end of the weld mark 50 deviates from the outer edge of the welding piece 23 or is located at the outer edge of the welding piece 23. In the present application, the welding piece 23 and the top cover 10 are welded by laser penetration welding. During welding, the starting end of the weld mark 50 between the welding piece 23 and the top cover 10 is deviated from the outer edge of the welding piece 23. Such a setting can make the edge of the welding piece 23 be avoided when the laser energy is insufficient, thereby ensuring the welding reliability and welding stability between the welding piece 23 and the top cover 10. When the starting end of the weld mark 50 between the welding piece 23 and the top cover 10 is located at the outer edge of the welding piece 23, the laser penetration welding process is not easy to produce welding marks at the non-contact position between the top cover 10 and the welding piece 23, which can ensure the integrity of the appearance of the top cover assembly. In the present application, it is preferred to produce the top cover assembly in a manner that the starting end of the weld mark 50 between the welding piece 23 and the top cover 10 deviates from the outer edge of the welding piece 23.

[0069] When the starting end of the weld mark 50 between the weld part 23 and the top cover 10 deviates from the outer edge of the weld part 23, the depth of the starting end of the weld mark 50 is not greater than the depth of the weld mark 50 at the edge of the weld part 23. In other words, the depth of the weld mark 50 at the starting end of the weld mark 50 is less than or equal to the depth of the weld mark 50 at the edge of the weld part 23, so that the welding effect between the weld part 23 and the top cover 10 can be guaranteed and the adverse effects of the welding functional area can be reduced.

[0070] The depth H of the weld mark 50 along the Z direction of the top cover 10 and the thickness D of the top cover 10 in the Z direction satisfy the relationship: 0.1D≤H≤0.6D. For example, H=0.1D, H=0.2D, H=0.3D, H=0.4D, H=0.5D, H=0.6D. By making the depth H of the weld mark 50 along the Z direction of the top cover 10 and the thickness D of the top cover 10 in the Z direction satisfy the relationship: 0.1D≤H≤0.6D, not only the welding stability between the welded part 23 and the top cover 10 can be ensured, but also the structural strength of the top cover 10 can be ensured.

[0071] Optionally, the width of the weld mark 50 along the X direction of the top cover 10 in this embodiment is L, wherein 0.5 mm ≤ L ≤ 2 mm, and 0.5 mm ≤ H ≤ 2 mm. For example, the depth H of the weld mark 50 in this embodiment may be 0.5 mm, 0.7 mm, 1 mm, 1.3 mm, 1.6 mm, 1.8 mm or 2 mm, etc., and the width L of the weld mark 50 may be 0.2 mm, 0.5 mm, 0.7 mm, 1 mm, 1.3 mm, 1.6 mm, 1.8 mm or 2 mm, etc. By making the depth H of the weld mark 50 along the Z direction of the top cover 10 and the width L along the X direction of the top cover 10 be 0.5 mm to 2 mm, the welding reliability between the welded part 23 and the top cover 10 and the structural strength of the top cover 10 can be taken into account.

[0072] To facilitate assembly, the welding piece 23 in this embodiment is clearance-fitted with the welding hole 12. This arrangement facilitates the insertion of the welding piece 23 into the welding hole 12, thereby improving the production efficiency of the top cover assembly in this embodiment.

[0073] Optionally, the gap between the outer wall of the welding piece 23 and the inner wall of the connecting hole 11 in this embodiment is not greater than 0.2 mm, for example, the maximum gap between the outer wall of the welding piece 23 and the inner wall of the connecting hole 11 may be 0.05 mm, 0.1 mm, 0.15 mm, or 0.2 mm. When the maximum gap between the outer wall of the welding piece 23 and the inner wall of the welding hole 12 is greater than 0.2, it is not convenient to perform laser penetration welding to weld the welding piece 23 and the top cover 10 together. That is to say, by making the maximum gap between the outer wall of the welding piece 23 and the inner wall of the connecting hole 11 not greater than 0.2, the present application can not only quickly insert the welding piece 23 into the welding hole 12, but also facilitate laser welding to weld the welding piece 23 and the top cover 10 together, thereby improving the welding yield.

[0074] Furthermore, the top cover assembly in this embodiment also includes a sealing ring 30, which is arranged on the side of the top cover 10 close to the pole component 20, that is, the sealing ring 30 is arranged between the first surface 101 and the pole component 20, and the sealing ring 30 is arranged around the outer periphery of the connecting hole 11, and the pole component 20 is pressed on the sealing ring 30 and covers the connecting hole 11. The setting of the sealing ring 30 can seal the gap between the top cover 10 and the pole component 20 to prevent leakage of the electrolyte inside the battery, and can also prevent other impurities from entering the gap between the pole component 20 and the top cover 10 and causing adverse effects on the top cover assembly. Exemplarily, the sealing ring 30 in this embodiment can be a rubber sealing ring, or a silicone sealing ring, etc.

[0075] Optionally, along the radial direction of the connection hole 11, the sealing ring 30 is located on one side of the welding section 232 close to the center of the connection hole 11. In other words, the sealing ring 30 is located inside the welding hole 12 and the welding piece 23. This arrangement makes it easier to limit the sealing ring 30 and prevent the sealing ring 30 from falling off during the assembly and production of the top cover assembly.

[0076] Furthermore, the pole component 20 in this embodiment includes a pole 21 and an upper plastic 22, the upper plastic 22 is arranged on the periphery of the pole 21, and the welding section 232 is fixedly connected to the upper plastic 22 and protrudes from the end face of the upper plastic 22 close to the first surface 101. In actual production, the upper plastic 22 can be injection molded on the periphery of the pole 21 by injection molding or the like, and the arrangement of the upper plastic 22 can play a good protective role for the pole 21. The welding piece 23 is connected to the upper plastic 22 and protrudes from the end face of the upper plastic 22 close to the first surface 101, so as to facilitate welding with the top cover 10 to weld and fix the pole component 20 on the top cover 10.

[0077] Furthermore, along the Z direction of the top cover 10, the top surface of the pole 21 in this embodiment (the end surface of the pole 21 facing away from the top cover 10) protrudes from the top surface of the upper plastic 22 (the end surface of the upper plastic 22 facing away from the top cover 10), that is, there is a step between the top of the pole 21 and the top of the upper plastic 22. This arrangement can prevent the upper plastic 22 from overflowing onto the top surface of the pole 21 during the injection molding process and affecting the conductivity of the pole 21. Optionally, as Fig. 9 As shown, in this embodiment, the end surface of the pole 21 away from the top cover 10 protrudes from the end surface of the upper plastic 22 away from the top cover 10 by a height H1 of 1 mm to 5 mm, such as 1 mm, 2 mm, 3 mm, 4 mm, or 2 mm.

[0078] Furthermore, the minimum distances from the inner side 2201 of the upper plastic 22 close to the pole 21, the side of the upper plastic 22 away from the top cover 10, and the outer side 2202 of the upper plastic 22 to the welding piece 23 are not less than a first predetermined value, and the first predetermined value is greater than or equal to 0.3 mm, such as 0.3 mm, 0.5 mm, 1 mm or 1.5 mm. In other words, except for the protruding end face of the welding piece 23, the minimum thickness from the welding piece 23 to each side of the upper plastic 22 is not less than 0.3 mm. Fig. 9As shown, the minimum distance between the inner side 2201 of the upper plastic 22 close to the pole 21 and the welding piece 23 is D5, the minimum distance between the side of the upper plastic 22 away from the top cover 10, that is, the upper side 2203 and the welding piece 23 is D6, and the minimum distance between the outer side 2202 of the upper plastic 22 and the welding piece 23 is D4. Among them, D4, D5 and D6 are all greater than or equal to 0.3mm. With such a configuration, the upper plastic 22 can be well covered on the outside of the welding piece 23, which is convenient for injection molding and for reserving sufficient creepage distance for the operation of the battery. Even if the top cover assembly is used for a long time, the welding piece 23 is difficult to peel off or fall off from the upper plastic 22.

[0079] Furthermore, the axial projection of the pole 21 in the connection hole 11 at least partially overlaps with the axial projection of the sealing ring 30 in the connection hole 11. Since the axial projection of the pole 21 in the connection hole 11 in this embodiment at least partially overlaps with the axial projection of the sealing ring 30 in the connection hole 11, when the pole 21 is subjected to external force and has a tendency to move toward the inside of the battery, the sealing ring 30 arranged on the top cover 10 can apply a supporting force to the pole 21. The existence of this supporting force can prevent the pole 21 from entering the inside of the battery installed with the top cover assembly of the present application from the connection hole 11, and further prevent the pole 21 from entering the inside of the battery and causing the risk of short circuit of the battery. It can be seen that the top cover assembly of the present application and the battery having the top cover assembly have lower production costs, higher safety and reliability in use.

[0080] The pole 21 includes a limiting portion, namely, the outer flange 212 mentioned below, which is disposed between the annular body 231 and the first surface 101, and the projection of the annular body 231 in the axial direction of the connection hole 11 at least partially overlaps with the projection of the limiting portion in the axial direction of the connection hole 11. That is to say, the welding piece 23 in this embodiment has an extended annular body 231 extending in the X direction perpendicular to the Z direction, and by making the projection of the annular body 231 in the axial direction of the connection hole 11 at least partially overlap with the projection of the limiting portion in the axial direction of the connection hole 11, when the welding piece 23 is subjected to a downward force, the limiting portion can play a limiting support role for the annular body 231, which can prevent the welding piece 23 from being peeled off from the upper plastic 22 from the side close to the top cover 10, and can improve the structural stability of the upper plastic 22, the pole 21 and the welding piece 23.

[0081] Furthermore, the pole 21 in this embodiment includes a main body 211 and an outer flange 212 located on the outer periphery of the main body 211. The outer flange 212 forms the above-mentioned limiting portion. The outer flange 212 is arranged on the outer periphery of the bottom end of the main body 211. By arranging the outer flange 212 on the outside of the main body 211, the structural stability between the upper plastic 22 and the pole 21 can be improved, and the upper plastic 22 is not easy to be separated from the pole 21. The bottom surface of the outer flange 212 is pressed on the sealing ring 30. When the pole 21 has a tendency to move toward the inside of the battery under the action of external force, the supporting force applied by the top cover 10 to the sealing ring 30 can act on the outer flange 212 to prevent the pole 21 from extending from the connection hole 11 into the inside of the battery under the action of external force.

[0082] Furthermore, the pole 21 in this embodiment includes a main body 211 and an outer flange 212 located at the outer periphery of the main body 211. The outer flange 212 is arranged at the outer periphery of one end of the main body 211 close to the first surface 101. By arranging the outer flange 212 on the outside of the main body 211, the structural stability between the upper plastic 22 and the pole 21 can be improved, and the upper plastic 22 is not easy to be peeled off from the pole 21. The bottom surface of the outer flange 212 is pressed on the sealing ring 30, that is, the sealing ring 30 is arranged on the side of the outer flange 212 close to the first surface 101, and the distance H2 from the outer side surface of the outer flange 212 to the welding piece 23 is greater than the distance H3 from the outer edge of the sealing ring 30 to the welding piece 23. In other words, the distance H2 from the outer edge of the outer flange 212 to the welding piece 23 is farther than the distance H3 from the outer edge of the sealing ring 30 to the welding piece 23. In this way, the phenomenon of battery short circuit caused by the pole 21 and the welding piece 23 being too close can be avoided.

[0083] Further, along the Z direction of the top cover 10, the top surface of the outer flange 212 (i.e., the side of the outer flange 212 away from the top cover 10) is flush with or higher than the top surface of the sealing ring 30 (the sealing ring 30 away from the top cover 10) and there is no side surface pressed by the outer flange 212. Fig. 9 As shown, the side of the outer flange 212 away from the top cover 10 is the first side 2121, and the side of the sealing ring 30 away from the top cover 10 and not pressed by the outer flange 212 is the second side 31. Fig. 9In the structure shown, the first side surface 2121 is higher than the sealing ring 30. When the compression amount of the sealing ring 30 remains constant, by making the side surface of the outer flange 212 away from the top cover 10 higher than the side surface of the sealing ring 30 away from the top cover 10 and not pressed by the outer flange 212, the thickness of the outer flange 212 can be increased to a certain extent, so that the connection stability between the upper plastic 22 and the pole 21 and the structural strength of the pole component 20 can be improved. When the thickness of the outer flange 212 along the Z direction remains unchanged, by making the side surface of the outer flange 212 away from the top cover 10 flush with the side surface of the sealing ring 30 away from the top cover 10 and not pressed by the outer flange 212, the sealing ring 30 can be effectively compressed, thereby improving the sealing performance of the top cover assembly in this embodiment. At the same time, by making the side of the outer flange 212 away from the top cover 10 flush with the side of the sealing ring 30 away from the top cover 10 and not pressed by the outer flange 212, there is no height difference between the first side 2121 of the outer flange 212 and the second side 31 of the sealing ring 30, and gaps are not likely to appear at this position, and materials such as metal chips are not likely to enter the gap, which can improve the safety performance of the top cover assembly in this embodiment to a certain extent.

[0084] Combination Figures 3 to 16 As shown, in order to facilitate the positioning and installation of the sealing ring 30 and the pole 21, an annular sink 13 is provided on the top cover 10 in this embodiment, and the annular sink 13 is located at the outer periphery of the connecting hole 11. The sealing ring 30 is provided on the annular sink 13, and the annular sink 13 can limit the sealing ring 30. Of course, in other embodiments of the present application, the annular sink 13 may not be provided on the top cover 10, and other deformation modes under the conception of the present application are within the protection scope of the present application.

[0085] Further, the welding hole 12 is located at the outer periphery of the annular sink 13, and the side wall of the welding hole 12 is close to and connected with the side wall of the annular sink 13. It can be understood that the side wall of the welding hole 12 described in this embodiment is close to and connected with the side wall of the annular sink 13, which means that the welding hole 12 and the annular sink 13 are close to each other, and at this time, the side walls of the two are just connected to form a gap. For details, please refer to Figure 3 As shown. In the present application, by placing the welding hole 12 close to the annular sink, the various structures of the top cover assembly can be made more compact, which facilitates the miniaturization of the top cover assembly. Of course, in other embodiments shown in the figures of the present application, the side wall of the welding hole 12 and the side wall of the annular sink 13 can also be spaced apart by a predetermined distance. In this way, the opening on the top cover 10 and the thinner area are spaced apart by a certain distance, which can improve the structural strength of the top cover assembly in this embodiment to a certain extent.

[0086] Furthermore, the welding hole 12 in this embodiment is arranged close to the annular sink 13, and along the radial direction of the connecting hole 11, the side wall surface of the welding hole 12 close to the connecting hole 11 is flush with the side wall surface of the annular sink 13 at the corresponding position. Fig.12 As shown, the side wall of the welding hole 12 close to the annular sink 13 is the first side wall surface 121, and the side wall corresponding to the position on the annular sink 13 is the second side wall surface 131. Fig.14 The figure shows the situation when the first side wall surface 121 is flush with the second side wall surface 131. Such a setting can take into account the contact area between the sealing ring 30 and the annular sink 13 while ensuring the structural strength of the annular sink 13. Of course, in other embodiments of the present application, the welding hole 12 is arranged close to the annular sink 13, and the side wall surface of the welding hole 12 close to the connecting hole 11 is not flush with the side wall surface at the corresponding position of the annular sink 13, that is, the side wall surface of the welding hole 12 close to the connecting hole 11, that is, the first side wall surface 121 can face the inside of the annular sink 13 (such as Fig.16 ) or external extension (as shown Fig.15 As shown), any other deformation methods based on the concept of this application are within the protection scope of this application.

[0087] See also Figure 8 and Fig.11 As shown, the top cover assembly also includes a lower plastic 40, and the lower plastic 40 includes a first plastic part 41 and a second plastic part 42. The first plastic part 41 includes an annular plastic body 411 and an annular protrusion 412 arranged at the top of the annular plastic body 411, the annular plastic body 411 is embedded in the connecting hole 11, and the annular protrusion 412 is arranged between the pole component 20 and the top cover 10; the second plastic part 42 is arranged on the second surface 102 and connected to the bottom end of the annular plastic body 411 as a whole; wherein the second plastic part 42 completely covers the welding hole 12, or the second plastic part 42 is provided with a avoidance hole 421 at a position corresponding to the welding hole 12.

[0088] When the second plastic portion 42 completely covers the welding hole 12 (see Figure 8 As shown in the figure, the welding step of the welding piece 23 and the welding hole 12 is before the injection molding process of the lower plastic 40. The annular protrusion 412 is not easy to be formed and fixed in the gap between the pole 21 and the top cover 10. However, the welding piece 23 is not easy to extend into the battery. The lower plastic 40 can well isolate the welding piece 23 from the battery. When the position corresponding to the second plastic part 42 and the welding hole 12 is provided with an avoidance hole 421 (see Fig.12As shown), the welding step of the welding part 23 at the welding hole 12 can be performed before the injection molding of the lower plastic 40. During welding, the welding part 23 and the top cover 10 can be welded and fixed together from the avoidance hole 421. At the same time, the pole 21 can press the annular protrusion 412, which can improve the structural strength and sealing performance of the top cover assembly in this embodiment.

[0089] Furthermore, the top cover 10 in this embodiment is a thin plate structure, and two pole components 20 are arranged on the top cover 10, one of which is a positive pole component and the other is a negative pole component. Figure 1 In the figure, the pole component 20 on the left is the positive pole component, and the pole component 20 on the right is the negative pole component. The structures of the positive pole component and the negative pole component in the present application are basically the same, except that the conductive material in the positive pole component is different from the conductive material in the negative pole component. Specifically, the pole 21 of the positive pole component is an aluminum pole, and the pole 21 of the negative pole component is a copper-aluminum pole, and the bottom of the copper-aluminum pole is an aluminum base. This arrangement makes it easier to weld and fix the poles 21 of the positive pole component and the negative pole component to the aluminum connecting piece inside the battery.

[0090] In order to facilitate the distinction between the positive pole component and the negative pole component, the pole component 20 in this embodiment is provided with a positive and negative pole mark 80. Optionally, the positive and negative pole mark 80 may be text, a pattern, a graphic, or a "+" or "-" sign. Figure 1 8 shows the case where the positive and negative pole marks 80 are "+" and "-". Through the role of the positive and negative pole marks 80, it is easy to identify the positive pole column component and the negative pole column component, which is more convenient for users to use.

[0091] Furthermore, the thickness D1 of the upper plastic 22, the thickness D2 of the annular protrusion, and the thickness D3 of the sealing ring compressed by the pole 21 satisfy the relationship: 3≥(D1-D3) / (D2+D3)≥0.5, for example, (D1-D3) / (D2+D3) can be 0.5, 1, 1.5, 2, 2.5 or 3.

[0092] It should be noted that the thickness D1 of the upper plastic 22 described in this embodiment refers to the thickness of the upper plastic 22 along the axial direction of the connecting hole 11. When the thickness of the upper plastic 22 along the axial direction of the connecting hole 11 varies at different positions, the thickness D1 of the upper plastic 22 mentioned here refers to the average thickness of the upper plastic 22 along the axial direction of the connecting hole 11; the thickness D2 of the annular convex refers to the thickness of the annular convex along the axial direction of the connecting hole 11. For details, please refer to Fig.10 The logo in .

[0093] In the present application, when (D1-D3) / (D2+D3)>3, the thickness D1 of the upper plastic 22 is relatively thick, while the thickness D2 of the annular bulge is relatively thin, and the compression amount of the sealing ring is relatively large. At this time, if the pole component 20 is pressed on the annular bulge, the upper side of the annular bulge is subjected to the pressure applied by the pole component 20, and it is very easy to break at the corner where the annular bulge and the annular plastic body 411 are connected, and it is easy for the lower plastic 40 to peel off from the top cover 10. When (D1-D3) / (D2+D3)<0.5, the thickness D1 of the upper plastic 22 is relatively thin, the thickness D2 of the ring convex is relatively thick, and the compression amount of the sealing ring is relatively small. The ring convex is not easy to be injection molded and fixed between the pole component 20 and the top cover 10, and the production scrap rate is relatively high. In addition, the increase in the thickness of the ring convex will also cause the overall thickness of the top cover assembly to increase and the mass to be greater. When the top cover assembly is used in a battery, the distance between the pole 21 and the adapter plate inside the battery is relatively far, which is not convenient for welding the pole 21 and the adapter plate inside the battery, and is not convenient for realizing the miniaturization design of the battery. That is to say, in this embodiment, by making the thickness D1 of the upper plastic 22, the thickness D2 of the annular convexity, and the thickness D3 of the sealing ring compressed by the pole 21 satisfy the following relationship: 3≥(D1-D3) / (D2+D3)≥0.5, it can not only ensure the overall structural strength of the top cover assembly and improve the yield rate of the top cover assembly in the production process, but also facilitate the miniaturization and lightweight design of the battery, and can reduce the height of the pole 21 exceeding the top cover surface on the basis of ensuring the sealing reliability and long-term life of the sealing ring, thereby increasing the space utilization rate of the top cover assembly in the Z direction.

[0094] Optionally, the upper plastic 22 and the lower plastic 40 in this embodiment are plastic parts, the upper plastic 22 is fixed on the pole 21 and the welding part 23 by injection molding, and the lower plastic 40 is arranged between the top cover 10 and the pole component 20 by injection molding.

[0095] In the present application, the thickness D3 of the sealing ring compressed by the pole 21 is ≥ 0.3 mm, such as 0.3 mm, 0.5 mm, 0.7 mm, 1 mm, 1.5 mm, etc. By making the thickness D3 of the sealing ring compressed by the pole 21 ≥ 0.3 mm, the gap between the top cover 10 and the pole component 20 can be well sealed to prevent leakage of the electrolyte inside the battery, and other impurities can be prevented from entering the gap between the pole component 20 and the top cover 10 and causing adverse effects on the top cover assembly and the battery. Exemplarily, the sealing ring in this embodiment can be a rubber sealing ring, or a silicone sealing ring, etc.

[0096] On the other hand, the present application also provides a battery, which includes the top cover assembly in the above-mentioned embodiment. Therefore, the battery includes all the technical effects of the top cover assembly in the above-mentioned embodiment. Since the technical effects of the top cover assembly have been described in detail above, they will not be repeated here.

[0097] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0098] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

[0099] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A top cover assembly, characterized in that: include: A top cover (10), wherein the top cover (10) is provided with a first surface (101) and a second surface (102) in the Z direction, and the top cover (10) is provided with a connection hole (11), and the connection hole (11) extends along the Z direction of the top cover (10); and A pole component (20), the pole component (20) being arranged on the first surface (101) and covering the connection hole (11), the pole component (20) comprising a welding piece (23), the welding piece (23) being welded and fixed on the top cover (10).

2. The top cover assembly according to claim 1, characterized in that: The top cover (10) is provided with a welding hole (12), the welding hole (12) is arranged to penetrate along the Z direction of the top cover (10), and the welding piece (23) is inserted into the welding hole (12) and is welded to the top cover (10).

3. The top cover assembly according to claim 2, characterized in that: The welding piece (23) comprises an annular body (231) and a plurality of welding segments (232), wherein the plurality of welding segments (232) are arranged at intervals along the circumference of the annular body (231), and each welding segment (232) extends along the Z direction of the top cover (10); There are a plurality of welding holes (12), and the plurality of welding holes (12) are arranged at intervals along the outer circumference of the connecting hole (11), and the plurality of welding segments (232) are inserted into the plurality of welding holes (12) one by one and are welded and fixed to the top cover (10).

4. The top cover assembly according to claim 3, characterized in that: The welding hole (12) is a through hole or a blind hole. When the welding hole (12) is a through hole, the bottom end surface of the welding section (232) is flush with or not flush with the bottom surface of the second surface (102).

5. The top cover assembly according to claim 3, characterized in that: The welding piece (23) and the top cover (10) are welded on the second surface (102) to form a welding mark (50), and the starting end of the welding mark (50) deviates from the outer edge of the welding piece (23) or is located at the outer edge of the welding piece (23).

6. The top cover assembly according to claim 5, characterized in that: The starting end of the weld mark (50) deviates from the outer edge of the weld part (23), and the depth of the starting end of the weld mark (50) is not greater than the depth of the weld mark (50) at the edge of the weld part (23).

7. The top cover assembly according to claim 6, characterized in that: The depth of the weld mark (50) along the Z direction of the top cover (10) is H, and the thickness of the top cover (10) in the Z direction is D, wherein 0.1D≤H≤0.6D.

8. The top cover assembly according to claim 7, characterized in that: The width of the weld mark (50) along the X direction of the top cover (10) is L, wherein 0.5 mm≤L≤2 mm, and 0.5 mm≤H≤2 mm.

9. The top cover assembly according to claim 3, characterized in that: The top cover assembly also includes: A sealing ring (30), wherein the sealing ring (30) is arranged between the first surface (101) and the pole component (20), and the sealing ring (30) is arranged around the outer periphery of the connecting hole (11). In the radial direction of the connecting hole (11), the sealing ring (30) is located on one side of the welding section (232) close to the center of the connecting hole (11).

10. The top cover assembly according to claim 9, characterized in that: The pole component (20) comprises a pole (21) and an upper plastic (22), wherein the upper plastic (22) is arranged on the outer periphery of the pole (21), and the welding section (232) is fixedly connected to the upper plastic (22) and protrudes from the end surface of the upper plastic (22) close to the first surface (101).

11. The top cover assembly according to claim 10, characterized in that: The minimum distance between the inner side surface (2201) of the upper plastic (22) close to the pole (21), the side surface of the upper plastic (22) away from the top cover (10), and the outer side surface (2202) of the upper plastic (22) and the welding part (23) is not less than a first predetermined value.

12. The top cover assembly according to claim 11, characterized in that: The first predetermined value is greater than or equal to 0.3 mm.

13. The top cover assembly according to claim 10, characterized in that: The projection of the pole (21) in the axial direction of the connecting hole (11) at least partially overlaps with the projection of the sealing ring (30) in the axial direction of the connecting hole (11).

14. The top cover assembly according to claim 10, characterized in that: The pole (21) comprises a limiting portion, which is arranged between the annular body (231) and the first surface (101), and a projection of the annular body (231) in the axial direction of the connecting hole (11) at least partially overlaps with a projection of the limiting portion in the axial direction of the connecting hole (11).

15. The top cover assembly according to claim 9, characterized in that: An annular sink (13) is provided on the top cover (10), the annular sink (13) is located on the outer periphery of the connecting hole (11), and the sealing ring (30) is provided on the annular sink (13).

16. The top cover assembly according to claim 15, characterized in that The welding hole (12) is located on the outer periphery of the annular sink (13), and the side wall of the welding hole (12) is connected to or spaced apart by a predetermined distance from the side wall of the annular sink (13).

17. The top cover assembly according to claim 2, characterized in that: There is a clearance fit between the welding piece (23) and the welding hole (12).

18. The top cover assembly according to claim 17, characterized in that The gap between the welding piece (23) and the connecting hole (11) is no greater than 0.2 mm.

19. The top cover assembly according to claim 10, characterized in that The pole (21) comprises a main body (211) and an outer flange (212) located on the outer periphery of the main body (211); the sealing ring (30) is arranged on a side of the outer flange (212) close to the first surface (101); and a distance H2 from an outer side surface of the outer flange (212) to the welding part (23) is greater than a distance H3 from an outer edge of the sealing ring (30) to the welding part (23).

20. The top cover assembly according to claim 19, characterized in that Along the Z direction, the top surface of the outer flange (212) is flush with or higher than the portion of the top surface of the sealing ring (30) that is not pressed by the outer flange (212).

21. The top cover assembly according to claim 9, characterized in that An annular sink (13) is provided on the top cover (10), the annular sink (13) is located on the outer periphery of the connecting hole (11), and the sealing ring (30) is provided on the annular sink (13).

22. The top cover assembly according to claim 21, characterized in that The welding hole (12) is located on the outer periphery of the annular sink (13), and the side wall of the welding hole (12) is connected to or spaced apart by a predetermined distance from the side wall of the annular sink (13).

23. The top cover assembly according to claim 22, characterized in that Along the radial direction of the connection hole (11), the side wall surface of the welding hole (12) close to the connection hole (11) is flush or uneven with the side wall surface at a corresponding position of the annular sink (13).

24. The top cover assembly according to claim 10, characterized in that The top cover assembly further comprises a lower plastic (40), wherein the lower plastic (40) comprises: A first plastic part (41), the first plastic part (41) comprising an annular plastic body (411) and an annular protrusion (412) arranged on the annular plastic body (411), the annular plastic body (411) being located in the connecting hole (11), and the annular protrusion (412) being arranged between the pole component (20) and the top cover (10); A second plastic part (42), the second plastic part (42) being disposed on the second surface (102) and integrally connected to the annular plastic body (411); The second plastic part (42) completely covers the welding hole (12), or a avoidance hole (421) is provided at a position corresponding to the second plastic part (42) and the welding hole (12).

25. The top cover assembly according to claim 24, characterized in that The thickness D1 of the upper plastic (22), the thickness D2 of the annular protrusion (412), and the thickness D3 of the sealing ring (30) compressed by the pole (21) satisfy the relationship: 3≥(D1-D3) / (D2+D3)≥0.

5.

26. The top cover assembly according to claim 25, characterized in that The sealing ring (30) is compressed by the pole (21) to a thickness D3 of ≥0.3 mm.

27. The top cover assembly according to claim 2, characterized in that The welding holes (12) are long strip holes, and a plurality of the welding holes (12) are arranged at intervals along the circumference of the first ring shape, and the sum of the lengths of the plurality of welding holes (12) accounts for 0.15 to 0.75 of the circumference of the first ring shape.

28. The top cover assembly according to claim 1, characterized in that The pole component (20) comprises a positive pole component and a negative pole component, and the pole component (20) comprises a pole (21). The pole (21) of the positive pole component is an aluminum pole, and the pole (21) of the negative pole component is a copper-aluminum pole, and the bottom of the copper-aluminum pole is an aluminum base.

29. A battery, characterized in that: The battery comprises the top cover assembly according to any one of claims 1 to 28.

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