Pole structure, cover plate assembly and battery

Abstract

The application provides a pole structure, a cover plate assembly and a battery. The pole structure comprises a pole connecting piece and a pole body. The pole connecting piece comprises a connecting part and a welding part. The connecting part and the welding part are arranged in a first direction. The welding part has a first surface and a second surface which are oppositely arranged in a third direction. The first surface is provided with a groove. The second surface has a welding working area. In a plane formed by the first direction and a second direction, the normal projection of the welding working area and the groove at least partially overlaps. The pole body is connected with the connecting part and protrudes outward from the first surface in the second direction. The third direction is the thickness direction of the pole connecting piece. The first direction and the second direction are perpendicular, and the third direction is perpendicular to the plane. The groove in the pole structure reduces the welding heat directly conducted to other structural parts through the welding part, thereby reducing the degree and probability of reliability problems and improving the reliability of the cover plate assembly and the battery. The reliability of the cover plate assembly and the battery is effectively improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of batteries, and relates to a pole post structure, a cover plate assembly and a battery. BACKGROUND

[0002] In the assembly process of a lithium ion battery, a welding process (for example, a laser welding process) is generally used to connect the pole lug of a pole group in a battery shell to a pole post structure on a battery cover plate, so as to establish an electrical connection path between the inside and outside of the battery. In actual application, it is found that during the operation of the battery, the battery cover plate and the battery occasionally have internal short circuit and liquid leakage problems, which affect the safety and reliability of the battery. SUMMARY

[0003] In view of the above-mentioned defects of the prior art, the purpose of the present application is to provide a pole post structure, a cover plate assembly and a battery, which are used to solve the problem that the reliability of the cover plate assembly and the battery in the prior art needs to be improved.

[0004] To achieve the above-mentioned purpose and other related purposes, in a first aspect, the present application provides a pole post structure, comprising:

[0005] A pole post connecting piece, comprising a connecting part and a welding part, the connecting part and the welding part are arranged in a first direction, the welding part has a first surface and a second surface, the first surface and the second surface are oppositely arranged in a second direction, the first surface is provided with a groove, and the second surface has a welding working area, in the second direction, the orthographic projection of the welding working area at least partially falls within the range of the orthographic projection of the groove;

[0006] A pole post body connected with the connecting part, and in the third direction, the pole post body protrudes out of the first surface, wherein the third direction is the thickness direction of the pole post connecting piece, the first direction and the second direction are perpendicular, and the third direction is perpendicular to the plane.

[0007] In an optional embodiment, in the plane, the orthographic projection of the welding working area is located within the range of the orthographic projection of the groove.

[0008] In an optional embodiment, in the third direction, the thickness of the welding part is h1 , and the depth of the groove is h2 , 0.1≤ h2 / h1 ≤0.5.

[0009] In an optional embodiment, in the plane, the cross-sectional profile of the groove is rectangular, the groove comprises a first sidewall, a second sidewall, a third sidewall and a fourth sidewall, the first sidewall and the second sidewall are oppositely arranged in the first direction, and the third sidewall and the fourth sidewall are oppositely arranged in the second direction; wherein,

[0010] In the first direction, the distance between the first sidewall and the edge of the welding portion close to the connecting portion is a , a ≥ 1 mm;

[0011] In the first direction, the distance between the second sidewall and the side of the welding portion away from the connecting portion is b , b ≥ 0.5 mm;

[0012] In the second direction, the distance between the third sidewall and the side of the welding portion close to the third sidewall is c , c ≥ 0.5 mm;

[0013] In the second direction, the distance between the fourth sidewall and the side of the welding portion close to the fourth sidewall is d , d ≥ 0.5 mm.

[0014] In an optional embodiment, in the plane:

[0015] In the first direction, the distance between the orthographic projection of the welding working area and the orthographic projection of the first sidewall is i , i ≥ 2 mm;

[0016] In the first direction, the distance between the orthographic projection of the welding working area and the orthographic projection of the second sidewall is j , j ≥ 2 mm;

[0017] In the second direction, the distance between the orthographic projection of the welding working area and the orthographic projection of the third sidewall is k , k ≥ 2 mm;

[0018] In the second direction, the distance between the orthographic projection of the welding working area and the orthographic projection of the fourth sidewall is l , l ≥ 2 mm.

[0019] In an optional embodiment, in the first direction, the length of the welding working area is e , and the length of the groove isf , 0.5≤ e / f ≤0.9.

[0020] In an optional embodiment, the welding working area comprises n n welding areas, and in the second direction, the sum of the widths of the n welding areas is g , and the width of the groove is h , 0.15≤ g / h ≤0.3.

[0021] In an optional embodiment, the pole post connector further comprises a melting portion, and in the first direction, the melting portion is connected between the connecting portion and the welding portion, and the melting portion is covered with a glue.

[0022] In a second aspect, the application provides a cover plate assembly, comprising a cover plate body, a first insulating member, and the pole post structure as described in the first aspect, wherein in the third direction, a part of the first insulating member is clamped between the welding portion and the cover plate body, and the first surface faces the first insulating member.

[0023] In a third aspect, the application provides a battery, comprising a tab and the cover plate assembly as described in the second aspect, and the tab is welded to the welding working area.

[0024] As described above, the pole post structure of the application comprises a pole post connector having a welding portion, and the first surface of the welding portion is provided with a groove, and in the plane formed by the first direction and the second direction, the orthogonal projection of the welding working area in the second surface of the welding portion at least partially falls within the range of the orthogonal projection of the groove. When the cover plate assembly provided with the pole post structure is welded with the tab (the tab is welded with the welding working area), the groove can act as a heat insulation structure to insulate at least part of the welding working area in the cover plate assembly from other structural members (for example, the first insulating member) via the air in the groove, reduce the welding heat directly conducted to the other structural members via the welding portion, and thus reduce the degree and probability of reliability problems of the other structural members caused by the welding heat, and improve the reliability of the cover plate assembly and the battery.

[0025] The cover plate assembly and the battery of the application can effectively improve the reliability due to the pole post structure. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 The pole post structure provided by the embodiment of the application is shown in a perspective view.

[0027] Figure 2 The pole post structure provided by the embodiment of the application is shown in a top view when the first surface faces the third direction.

[0028] Figure 3 is a schematic view of a cross section along Figure 2

[0029] Figure 4 is a top view schematic view of the pole structure provided by the embodiment of the present application when the welding working area is shown.

[0030] Figure 5 is a perspective view schematic view of the battery partial structure provided by the embodiment of the present application.

[0031] Figure 6 is an exploded view schematic view of the battery partial structure provided by the embodiment of the present application.

[0032] Figure 7 is a top view schematic view of the battery partial structure provided by the embodiment of the present application.

[0033] Figure 8 is a schematic view of a cross section along Figure 7

[0034] Figure 9 is a bottom view schematic view of the battery partial structure provided by the embodiment of the present application.

[0035] BRIEF DESCRIPTION OF DRAWINGS

[0036] 10-pole structure, 11-pole connecting piece, 111-connecting part, 112-welding part, 112a-first surface, 112b-second surface, 113-groove, 113a-first side wall, 113b-second side wall, 113c-third side wall, 113d-fourth side wall, 114-welding working area, 1141-welding area, 115-fusing part, 116-gluing, 12-pole main body, 121-main body connecting part, 122-main body extending part, 123-main body riveting part;

[0037] 20-cover plate assembly, 21-cover plate body, 22-first insulating piece, 23-sealing ring, 24-second insulating piece, 25-riveting block;

[0038] 30-battery partial structure, 31-tab, 32-welding mark. DETAILED DESCRIPTION

[0039] The above embodiments of the present application can be implemented or applied in other different specific embodiments, and the details in the present specification can be modified or changed based on different views and applications without departing from the spirit of the present application.

[0040] ​​Please refer to Figures 1 to 9 It is to be noted that the diagrams provided in the embodiments are only schematic and that, in particular, the proportions of the various components are not necessarily to scale with respect to one another. The dimensions of the various features and components can be arbitrarily increased or reduced with respect to the actual implementation.

[0041] For the technical problems mentioned in the background, after disassembling and analyzing the battery with reliability problems, it is found that, in the manufacturing of lithium ion batteries, the internal connecting piece (especially the positive connecting piece) of the battery serves as a key conductive component for connecting the battery pole group and the cover plate assembly. Its reliable electrical connection with the cover plate assembly (such as the pole) is crucial. Currently, laser welding process is commonly used to complete this connection to meet the requirements of low resistance and high strength.

[0042] However, during the welding of the tab and the connecting piece, a transient high temperature is generated at the welding point between the tab and the connecting piece. The high temperature generated by welding will inevitably conduct rapidly along the connecting piece to the contact area of the cover plate assembly. Generally, the side of the cover plate assembly facing the pole group is provided with an insulating piece (for example, a first insulating piece) to electrically isolate other structural pieces in the cover plate assembly from the pole group. When the welding heat is conducted to the area adjacent to the insulating piece, the insulating piece is sensitive to heat, and when the temperature exceeds its thermodynamic tolerance limit (for example, exceeds the melting point), it will cause the insulating piece to melt, deform or even ablate, directly destroying its structural integrity and insulating barrier function, thereby causing insulation failure risk and further causing reliability problems. For example, causing electrical short circuit between the internal live parts (pole group, connecting piece) and the metal shell, sealing failure of the cover plate assembly, and electrolyte leakage risk.

[0043] The embodiments of the present application provide a pole structure, please refer to Figure 1 , Figure 1 shows a perspective view of the pole structure. The pole structure 10 includes a pole connecting piece 11 and a pole main body 12. In order to facilitate the illustration of the specific structure of the pole structure, the first direction X in the following is the length direction of the pole connecting piece, the second direction Y is the width direction of the pole connecting piece, and the third direction Z is the thickness direction of the pole connecting piece. In addition, in the drawings provided by the embodiments of the present application, the first direction X to the third direction Z are all shown with one-way arrows, and in fact, there is no more specific direction in each direction. Taking the first direction X as an example, the first direction X includes the -X direction and the +X direction.

[0044] Specifically, please refer to Figure 2 and Figure 3 , Figure 2 shows a top view of the pole structure,Figure 3 Fig. 2 shows a cross-sectional view along Figure 2 Fig. 3 shows a cross-sectional view along Figure 4 Fig. 4 shows a top view of the pole structure with the welding working area. Figure 4 Fig. 5 shows a top view of the pole structure with the welding working area. Figure 1 Fig. 6 shows a top view of the pole structure with the welding working area. Figure 3 Fig. 7 shows a top view of the pole structure with the welding working area.

[0045] It should be noted that the welding working area 114 is located on the second face 112b, and cannot be shown on the top view of the pole structure 10. In order to facilitate the illustration of the corresponding position relationship between the welding working area 114 and the recess 113, Figure 4 Fig. 4 shows a top view of the pole structure with the welding working area.

[0046] The pole structure 10 in the embodiments of the present application includes the pole connecting member 11 with the welding part 112, and the first face 112a of the welding part 112 is provided with the recess 113. In the plane formed by the first direction X and the second direction Y, the orthographic projection of the welding working area 114 in the second face 112b of the welding part 112 in the third direction Z at least partially falls within the range of the orthographic projection of the recess 113. Thus, when the cover plate assembly with the pole structure 10 is assembled, and the pole tabs of the pole group are welded (specifically, the pole tabs are welded with the welding working area 114), the recess 113 can serve as a heat insulation structure to insulate other structural members in the cover plate assembly (for example, the pole connecting member 11, the pole structure 10, and the like) from the welding working area 114. Figure 6 Figure 8 ​The first insulating element 22 shown faces at least a portion of the welding work area 114 and is isolated from the welding part 112 by air within the groove 113. Since the thermal conductivity of air is much lower than that of metal, the heat directly conducted to other structural components via the welding part 112 can be reduced, thereby lowering the probability and severity of reliability problems in other structural components caused by welding heat. For example, normally, the first surface 112a of the welding part 112 is in direct contact with the first insulating element 22 in the cover assembly 20, and the first insulating element 22 is sensitive to high temperatures and may undergo irreversible deformation, melting, or even ablation due to absorbing high-temperature heat. This further improves the reliability of the cover assembly 20 and the battery.

[0047] In some embodiments, such as Figure 4 As shown, on this plane (i.e., the XY plane), the orthographic projection of the welding work area 114 lies within the range of the orthographic projection of the groove 113. That is, the orthographic projection of the welding work area 114 in the third direction Z at least partially falling within the range of the orthographic projection of the groove 113 includes two scenarios: a first part of the orthographic projection of the welding work area 114 in the third direction Z falls within the range of the orthographic projection of the groove 113, and a second part of the orthographic projection of the welding work area 114 in the third direction Z falls outside the range of the orthographic projection of the groove 113 (i.e., the two orthographic projections have overlapping areas and their own independent areas), or the orthographic projection of the welding work area 114 completely falls within the range of the orthographic projection of the groove 113. As mentioned earlier, the groove 113 is provided to form a heat insulation structure between the welding work area 114 and other structural components in the cover plate assembly, so as to prevent the welding part 112 from directly conducting the heat of the welding work area 114 to other structural components. If the orthographic projections of the two only partially overlap, it means that the first part of the welding working area 114 (the part whose orthographic projection overlaps with the orthographic projection of the groove 113) is air-isolated from other structural components via the groove 113. The heat from the second part of the welding working area 114 (the part whose orthographic projection is independent of the orthographic projection of the groove 113) is still directly conducted to other structural components via the portion of the weld 112 adjacent to the groove 113, thus causing reliability problems. Therefore, although partial overlap can reduce the probability and risk of reliability problems to some extent compared to not having the groove 113, the improvement effect is relatively limited. Therefore, in this embodiment, it is preferable that the orthographic projection of the welding working area 114 is within the range of the orthographic projection of the groove 113 to effectively improve the reliability problems caused by the conduction of welding heat in the cover plate assembly.

[0048] In some embodiments, such as Figures 1 to 3As shown, the pole connecting piece 11 further comprises a fusing portion 115, in the first direction X, the fusing portion 115 is connected between the connecting portion 111 and the welding portion 112, and the fusing portion 115 is covered with a rubber coating 116. The fusing portion 115 is used for self-adaptive fusing in the case of abnormality inside the battery (for example, overcurrent, overheat), to ensure the safety and reliability of the battery. The rubber coating 116 is an insulating material. Since the fusing portion 115 is usually provided with a relatively weak structure to respond to abnormal conditions in time, the rubber coating 116 covering the fusing portion 115 can improve the structural stability and reliability of the fusing portion 115 under normal conditions, and can avoid the metal splashes / particles generated by the melting of the fusing portion 115 from splashing into other areas inside the battery, thereby avoiding the occurrence of secondary faults such as short circuit. The rubber coating 116 covering the fusing portion 115 refers to covering the surface of the fusing portion 115, and in order to ensure the stable covering effect of the fusing portion 115, the rubber coating 116 also covers the side of the connecting portion 111 close to the fusing portion 115, and / or the rubber coating 116 also covers the side of the welding portion 112 close to the fusing portion.

[0049] In some embodiments, in the X-Y plane, the cross-sectional profile of the groove 113 can be rectangular, circular, racetrack-shaped, elliptical or other regular polygonal shape, and a suitable profile is selected under the premise that an effective isolation effect on the insulating member can be achieved. In the embodiments of the present application, the groove 113 is exemplarily illustrated as rectangular. Further, as shown in Figure 2 and Figure 4 shown, in the X-Y plane, the cross-sectional profile of the groove 113 is rectangular, and the groove 113 comprises a first side wall 113a, a second side wall 113b, a third side wall 113c and a fourth side wall 113d, wherein the first side wall 113a and the second side wall 113b are oppositely arranged in the first direction X, and the third side wall 113c and the fourth side wall 113d are oppositely arranged in the second direction.

[0050] Further, as shown in Figure 2 in the first direction X, the distance between the first side wall 113a and the side of the welding portion 112 close to the connecting portion 111 is a , a ≥1mm, for example, a may be 1mm, 2mm or 5mm. In the first direction X, the distance between the second side wall 113b and the side of the welding portion 112 away from the connecting portion 111 is b , b ≥0.5mm, for example, b may be 0.5mm, 1.5mm or 3mm.

[0051] Table 1, test results of specific embodiments and comparative examples with different a~d

[0052]

[0053] Further, in the second direction Y, the distance between the third side wall 113c and the side of the welding portion 112 close to the third side wall 113c is c , c ≥ 0.5 mm, for example, c may be 0.5 mm, 2 mm, or 3.5 mm. In the second direction Y, the distance between the fourth side wall 113d and the side of the welding portion 112 close to the fourth side wall 113d is d , d ≥ 0.5 mm, for example, d may be 0.5 mm, 1.2 mm, or 2.4 mm. In the case where the pole connecting piece 11 further has a melting portion 115, the edge of the welding portion 112 close to the connecting portion 111 is the connection between the welding portion 112 and the melting portion 115, a which can also be regarded as the distance between the first side wall 113a and the melting portion 115. Further, a ~ d The four structural parameters can be the same or different.

[0054] In some embodiments, as Figure 3 indicated, in the third direction Z, the thickness of the welding portion 112 is h1 , the depth of the groove 113 is h2 , 0.1 ≤ h2 / h1 ≤ 0.5, for example, h2 / h1 may be 0.1, 0.3, or 0.5.

[0055] Table 2, test results of specific embodiments with different h1 / h2 and comparative examples

[0056]

[0057] In the embodiments of the present application, the thickness of the welding portion 112 at the position corresponding to the groove 113 is thinner than the thickness of other parts due to the setting of the groove 113. As can be seen from Table 2, if the ratio of the depth of the groove 113 to the thickness of the welding portion 112 is too high (for example, h1 / h2 > 0.5), the mechanical strength of the part of the welding portion 112 below the groove 113 will be low, and in the subsequent welding of the cover plate assembly 20 and the tab 31 provided with the pole structure 10, a certain force will be generated on the remaining part below the groove 113, which will cause the part of the welding portion 112 corresponding to the groove 113 to deform or even break during the welding process, which may h1 / h2 ​If the value is less than 0.1, then the setting of groove 113 cannot bring about an effective heat insulation effect, and there will still be insulation failure problems such as melting of the first insulating component.

[0058] In some embodiments, such as Figure 4 As shown, in the first direction X, the length of the welding work area 114 is e The length of groove 113 is f 0.5≤ e / f ≤0.9, for example, e / f It can be 0.5, 0.7, or 0.9.

[0059] Table 3 shows those with different characteristics. e / f Specific embodiments and comparative test results

[0060]

[0061] In some embodiments, such as Figure 4 As shown, the welding work area 114 includes n welding areas 1141, in the second direction Y. n The sum of the widths of the 1141 welding zones is g The width of groove 113 is h 0.15≤ g / h ≤0.3. That is, g=∑g i ,1≤ i≤n , g i For the n welding zones 1141, the first i The width of the welding area 1141, for example, g / h It can be 0.15, 0.22, or 0.3.

[0062] In this embodiment, since the groove 113 is a structure designed for the welding work area 114, the dimensions of the two need to be matched as closely as possible to ensure stable welding between the electrode tab 31 and the welding part 112, while also ensuring good heat insulation for the first insulating component. As shown in Tables 3 and 4, if the welding work area 114 occupies too small a corresponding dimension of the groove 113, for example... e / f <0.5 (and / or, g / h <0.15), besides not fully utilizing the heat insulation space provided by the groove 113, it also results in a small proportion of the length or overall width of the welding working area 114, affecting the connection effect between the electrode tab 31 and the welding part 112. Conversely, if the welding working area 114 occupies too large a corresponding dimension of the groove 113, for example, e / f >0.9 (and / or, g / hIn the case of >0.3), although the heat insulation space provided by the groove 113 is fully utilized, the distance between the welding work area 114 and the welding part 112 around the groove 113 is relatively close. The heat generated during the welding process will be conducted to the first insulating part through the area of ​​the welding part 112 adjacent to the groove 113. The first insulating part may still undergo slight melting or deformation during the welding process, and long-term insulation reliability cannot be guaranteed.

[0063] Table 4 shows those with different characteristics. g / h Specific embodiments and comparative test results

[0064]

[0065] It should be noted that the accompanying drawings of this application embodiment illustrate the welding work area 114 as including two welding areas 1141. In actual applications, the welding work area 114 may include one or more than two welding areas 1141, and the number of welding areas 1141 is selected based on actual needs. The length and width of each welding area 1141 may be equal or unequal.

[0066] To avoid ambiguity, if the welding work area 114 includes only one welding area 1141, the welding area 1141 directly constitutes the welding work area 114. However, if the welding work area 114 includes more than one welding area 1141, and the welding area 1141 is rectangular, the multiple welding areas 1141 are arranged at intervals in the second direction Y (for example, arranged in an aligned interval or arranged in an alternating interval). At this time, the extension lines of the welding area 1141 closest to the first sidewall 113a in the first direction X, the extension lines of the welding area 1141 closest to the third sidewall 113c in the second direction Y, the extension lines of the welding area 1141 closest to the second sidewall 113b in the first direction X, and the extension lines of the welding area 1141 closest to the fourth sidewall 113d in the second direction Y, intersect in pairs to form a rectangular area, which is the welding work area 114.

[0067] In some embodiments, such as Figure 4 As shown, in the XY plane: the distance between the orthographic projection of the welding work area 114 and the orthographic projection of the first sidewall 113a is... i , i ≥2mm, for example, i It can be 2, 4, or 6. In the first direction X, the distance between the orthographic projection of the welding work area 114 and the orthographic projection of the second sidewall 113b is... j , j ≥2mm, for example,j may be 2, 5 or 7. In the second direction Y, the distance between the orthogonal projection of the welding working area 114 and the orthogonal projection of the third side wall 113c is k , k may be 2, 5 or 8. In the second direction Y, the distance between the orthogonal projection of the welding working area 114 and the orthogonal projection of the fourth side wall 113d is l , l may be 2, 5 or 8. In the second direction Y, the distance between the orthogonal projection of the welding working area 114 and the orthogonal projection of the fourth side wall 113d is l may be 2, 4 or 7. Further, i l The four structure parameters can be the same or different.

[0068] Table 5, specific embodiments with different i l Test results of specific embodiments and comparative examples

[0069]

[0070] In the embodiments of the present application, as can be seen from Table 5, the above-mentioned i l The range setting of the four distance parameters can avoid the distance between the welding working area 114 and the side wall of the groove 113 being too small, so that the welding heat of the welding working area 114 is conducted from the adjacent area of the groove 113 to the first insulating piece, thereby causing the probability of slight failure of the first insulating piece. In addition, the above-mentioned i l The four distance parameters are also not recommended to be set too large (for example, reaching 15 mm), otherwise although the reliability of the cover plate assembly can be ensured, the structure design of the pole is affected, and the weight and cost of the pole are increased.

[0071] It should be noted that the pole structure provided in the embodiments of the present application is particularly suitable for being assembled in a riveting type cover plate assembly, and therefore, Tables 1-5 provided in the embodiments of the present application are based on the pole structure being assembled in the cover plate assembly, and the results are collected whether the first insulating piece in direct contact with the welding portion 112 is affected by the welding heat.

[0072] In some embodiments, the pole structure 10 is a split connection structure. For example, as shown in Figure 3 , that is, the pole connecting piece 11 and the pole main body 12 are respectively manufactured and then assembled to form the pole structure 10. For example, the connecting portion 111 is provided with a connecting hole matched with the appearance of the main body connecting portion 121, and the main body connecting portion 121 is embedded in the connecting hole to connect the pole main body 12 to the connecting portion 111. The pole structure 10 with a split connection structure has higher manufacturing efficiency and yield.

[0073] ​​​​In some embodiments, the pole post structure 10 is a split structure. That is, the pole post connector 11 and the pole post body 12 are manufactured by a split connection process to form the pole post structure 10, or the pole post connector 11 and the pole post body 12 are processed based on the same base piece. Compared with the split connection structure, the overall mechanical strength and stability of the pole post structure 10 can be improved, and the assembly process of the parts can be reduced.

[0074] The embodiments of the present application also provide a cover plate assembly, please refer to Figure 5 and Figure 6 wherein, Figure 5 a perspective view of a partial structure of a battery is shown, Figure 6 an exploded view of the partial structure of the battery is shown. The cover plate assembly 20 includes a cover plate body 21, a first insulating piece 22, and the pole post structure 10 as described above, wherein in the third direction Z, a part of the first insulating piece 22 is clamped between the welding portion 112 and the cover plate body 21, and the first surface 112a faces the first insulating piece 22. In a specific example, the first insulating piece 22 is a lower plastic.

[0075] In some embodiments, the cover plate assembly 20 is a riveted cover plate, and the pole post body 12 includes a body connector portion 121, a body extension portion 122, and a body rivet portion 123 connected in sequence in the third direction Z. The cover plate assembly 20 further includes a sealing ring 23, a second insulating piece 24, and a riveting block 25, wherein the sealing ring 23 is sleeved on the body extension portion 122, the body extension portion 122 sleeved with the sealing ring 23 penetrates the first insulating piece 22, the cover plate body 21, and the second insulating piece 24 in sequence to extend into the riveting block 25, and the body rivet portion 123 is riveted and fixed with the riveting block 25. In a specific example, the second insulating piece 24 is an upper plastic, and the cover plate body 21 is an aluminum plate.

[0076] The cover plate assembly of the embodiments of the present application can effectively improve the reliability due to the assembly of the pole post structure.

[0077] The embodiments of the present application also provide a battery, Figure 6 a partial structure of the battery is shown, Figure 6 only the structure of the cover plate assembly and the tab of the battery is shown in the partial structure 30 of the battery. The battery includes the tab 31 and the cover plate assembly 20 as described above, and the tab 31 is welded and connected with the welding working area 114 of the welding portion 112.

[0078] Please refer to Figures 7 to 9 wherein, Figure 7 a top view of the partial structure of the battery is shown, Figure 8 a cross-sectional view along Figure 7 B-B' in FIG. 6 is shown, Figure 9 a bottom view of the partial structure of the battery is shown. FromFigure 8 As can be seen, after the tab 31 is welded with the cover plate assembly 20, at least one welding mark 32 is formed at the area where the tab 31 is connected with the welding portion 112, the position of the welding mark 32 is located within the welding working area 114 on the second surface 112b of the welding portion 112, and each welding mark 32 is formed based on the position of a welding area 1141.

[0079] The battery of the embodiment of the present application can effectively improve the reliability due to the cover plate assembly with the pole structure.

[0080] The above embodiments only exemplarily illustrate the principles and effects of the present application, and are not used to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical thought of the present application should be covered by the claims of the present application.

Claims

1. A pole structure, characterized by, The pole post connecting piece comprises a connecting part and a welding part, the connecting part and the welding part are arranged in a first direction, the welding part has a first surface and a second surface, the first surface and the second surface are oppositely arranged in a third direction, the first surface is provided with a groove, and the second surface has a welding work area, in a plane formed by the first direction and a second direction, a normal projection of the welding work area at least partially falls within a range of a normal projection of the groove. The pole post body is connected with the connecting part, and in the third direction, the pole post body protrudes out of the first surface, wherein the third direction is a thickness direction of the pole post connecting piece, the first direction and the second direction are perpendicular, and the third direction is perpendicular to the plane. In the plane, the normal projection of the welding work area is located within the range of the normal projection of the groove.

2. The pole structure of claim 1, wherein: In the plane, a cross-sectional appearance of the groove is rectangular; the groove comprises a first side wall, a second side wall, a third side wall and a fourth side wall, the first side wall and the second side wall are oppositely arranged in the first direction, and the third side wall and the fourth side wall are oppositely arranged in the second direction; wherein, 3. The pole structure of claim 2, wherein: In the third direction, a thickness of the weld is h1 , a depth of the groove is h2 , 0.1≤ h2 / h1 ≤0.

5.

4. The pole structure of claim 2, wherein: In the plane: In the first direction, the distance between the first side wall and the edge of the weld proximal to the connection is a , a ≥ 1 mm; In the first direction, the distance between the second side wall and the face of the weld remote from the connection is b , b ≥ 0.5 mm; In the second direction, the distance between the third side wall and the face of the weld proximate the third side wall is c , c ≥ 0.5 mm; In the second direction, the distance between the fourth side wall and the face of the weld proximate the fourth side wall is d , d ≥ 0.5 mm.

5. The pole structure of claim 4, wherein, The pole post connecting piece further comprises a fuse part, in the first direction, the fuse part is connected between the connecting part and the welding part, and the fuse part is covered with a rubber. In the first direction, the distance between the orthographic projection of the welding work area and the orthographic projection of the first side wall is i , i ≥ 2 mm; In the first direction, the distance between the orthographic projection of the welding work area and the orthographic projection of the second side wall is j , j ≥ 2 mm; In the second direction, the distance between the orthographic projection of the welding work area and the orthographic projection of the third side wall is k , k ≥ 2 mm; In the second direction, the distance between the orthographic projection of the welding work area and the orthographic projection of the fourth side wall is l , l ≥ 2 mm.

6. The pole structure of claim 2, wherein: In the first direction, the length of the welding work area is e , the length of the groove is f , 0.5≤ e / f ≤0.

9.

7. The pole structure of claim 2, wherein: The welding work area includes n welding areas, and the sum of the widths of the n welding areas in the second direction is g , the width of the groove is h , 0.15≤ g / h ≤0.

3.

8. The pole structure of claim 1, wherein: The cover plate assembly comprises a cover plate body, a first insulating part and the pole post structure according to any one of claims 1-8; wherein, 9. A cover plate assembly characterized by, In the third direction, a part of the first insulating part is clamped between the welding part and the cover plate body, and the first surface faces the first insulating part. The cover plate assembly comprises a cover plate body, a first insulating part and the pole post structure according to any one of claims 1-8; wherein, 10. A battery, characterized by: In the third direction, a part of the first insulating part is clamped between the welding part and the cover plate body, and the first surface faces the first insulating part. The cover plate assembly comprises a cover plate body, a first insulating part and the pole post structure according to any one of claims 1-8; wherein, In the third direction, a part of the first insulating part is clamped between the welding part and the cover plate body, and the first surface faces the first insulating part.

Images