Secondary battery, battery pack, and electronic device

Abstract

The utility model provides a secondary battery, a battery pack and an electronic device. The secondary battery comprises a shell, a pole, an insulation sealing assembly and an electrode assembly, the shell comprises an end wall, and a pole hole is formed in the end wall; the terminal post is riveted and fixed in the terminal post hole and comprises a post body and a riveting turnup, the post body penetrates through the terminal post hole, and the riveting turnup is arranged in the shell and is connected with the post body; the insulation sealing assembly is arranged between the pole and the end wall and enables the pole and the end wall to be sealed and insulated; the electrode assembly is installed in the shell and electrically connected with the pole and the shell. Wherein the terminal post further comprises a reinforcing part, and the reinforcing part is positioned on the riveting turnup edge and is configured to prevent the riveting turnup edge from shrinking and deforming. According to the secondary battery, the technical problem that the pole is easily separated from the pole hole in the shell in a thermal runaway state can be solved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a secondary battery, battery pack, and electronic device. Background Technology

[0002] During storage, charging, and discharging, secondary batteries undergo various electrochemical and thermodynamic reactions. If thermal runaway occurs, the secondary battery will short-circuit instantaneously and release a large amount of heat, causing a rapid rise in internal temperature. Most existing secondary batteries use riveting to attach the terminals to the casing. During thermal runaway, the high temperature and pressure inside the casing can cause warping and deformation of the casing's end walls, which in turn deforms the bottom of the casing at the terminal flange area. This can cause the terminal to fly out of the terminal hole in the casing. Once the terminal flies out, on the one hand, charged / conductive materials burning inside the cell can further escape through the terminal hole, potentially leading to system-level thermal runaway; on the other hand, the terminal itself is conductive, and after flying out, it can easily connect with the positive and negative terminals of the system / other secondary batteries, also posing a risk of system-level thermal runaway. Utility Model Content

[0003] This invention provides a secondary battery, a battery pack, and an electronic device to improve the technical problem that the terminals are prone to detach from the terminal holes on the casing under thermal runaway conditions.

[0004] To achieve the above and other related objectives, this utility model provides a secondary battery, comprising: a casing, terminals, an insulating and sealing assembly, and an electrode assembly. The casing includes an end wall with a terminal hole; the terminal is riveted and fixed within the terminal hole and includes a column and a riveting flange, the column extending through the terminal hole, and the riveting flange disposed within the casing and connected to the column; the insulating and sealing assembly is disposed between the terminal and the end wall, providing a sealed insulation between the terminal and the end wall; the electrode assembly is installed within the casing and electrically connected to the terminal and the casing. The terminal further includes a reinforcing portion, at least partially located on the riveting flange, and configured to prevent the riveting flange from shrinking and deforming.

[0005] In one embodiment of the secondary battery of this utility model, the reinforcing part includes a recess formed by partial pressing, and the recess is disposed on the side of the riveting flange away from the end wall.

[0006] In one embodiment of the secondary battery of this utility model, the recess depth of the recess is 1 / 3 to 1 / 2 of the maximum thickness of the riveted flange at the corresponding position of the recess.

[0007] In one embodiment of the secondary battery of this utility model, the riveting flange includes a riveting deformation protrusion farthest from the end wall, the riveting deformation protrusion surrounds the outer periphery of the column, and the recess extends from the outside of the riveting deformation protrusion to the inside of the riveting deformation protrusion.

[0008] In one embodiment of the secondary battery of this utility model, the riveting flange includes a riveting deformation protrusion farthest from the end wall, and the riveting deformation protrusion surrounds the outer periphery of the column; the recess includes a first groove and a second groove, the first groove and the second groove are intersecting and communicating with each other, and the first groove and the second groove extend from the outside of the riveting deformation protrusion to the inside of the riveting deformation protrusion.

[0009] In one embodiment of the secondary battery of this utility model, the reinforcing part includes a partially thickened reinforcing rib, which is disposed on the side of the riveted flange away from the end wall and is at least partially located within the riveted flange.

[0010] In one embodiment of the secondary battery of this utility model, the column is a cylindrical structure, the cylindrical structure includes an inner wall surface, the riveted flange includes an outer wall surface on the side opposite to the end wall, one end of the reinforcing rib is located on the inner wall surface, and the other end extends along the riveted flange to the outer wall surface.

[0011] In one embodiment of the secondary battery of this utility model, the column includes a separator located inside the cylindrical structure, one end of the reinforcing rib is connected to the separator, and the other end of the reinforcing rib extends to the outer periphery of the riveted flange.

[0012] In one embodiment of the secondary battery of this utility model, the width of the reinforcing rib gradually increases along the direction extending from the inner wall surface to the outer wall surface.

[0013] In one embodiment of the secondary battery of this utility model, the riveting flange includes a plurality of recesses, the number of the recesses is ≥4, and the plurality of recesses are evenly distributed on the riveting flange around the center of the column.

[0014] In one embodiment of the secondary battery of this utility model, the plurality of recesses are centrally symmetrical about the center of the electrode post.

[0015] In one embodiment of the secondary battery of this utility model, the insulating sealing assembly includes a lower insulating member, a portion of which is disposed between the riveting flange and the end wall. The secondary battery also includes a gasket, which is disposed between the lower insulating member and the riveting flange. The gasket is provided with an avoidance structure for the riveting flange to deform and enter during the riveting process.

[0016] In one embodiment of the secondary battery of this utility model, the avoidance structure includes a through hole that penetrates the gasket along the thickness direction of the gasket.

[0017] In one embodiment of the secondary battery of this utility model, the avoidance structure includes a groove, the groove includes a first groove segment and a second groove segment, one end of the first groove segment penetrates the contact surface between the gasket and the riveting flange, the other end of the first groove segment extends away from the riveting flange and communicates with the second groove segment, and the cross-sectional area of ​​the first groove segment is smaller than the cross-sectional area of ​​the second groove segment.

[0018] This utility model also provides a battery pack, which includes any of the above-mentioned secondary batteries.

[0019] This invention also provides an electronic device that includes the aforementioned battery pack.

[0020] This utility model of a secondary battery strengthens the riveted flange by providing a reinforcing part on the riveted flange of the terminal post. When high temperature and pressure are generated inside the secondary battery casing and the end wall of the casing warps and deforms, the probability of the riveted flange of the terminal post shrinking and deforming and flying out of the terminal post hole can be reduced. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other embodiments can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of an example of the secondary battery of this utility model;

[0023] Figure 2 This is a schematic diagram of the electrode assembly structure in an example of the secondary battery of this utility model;

[0024] Figure 3 for Figure 1 A partial enlarged view of one end of the electrode post in an example of a secondary battery of this utility model.

[0025] Figure 4 for Figure 3 A bottom view of a secondary battery;

[0026] Figure 5 for Figure 3 A partial three-dimensional view of one end of the terminal of a secondary battery;

[0027] Figure 6This is a bottom view of one end of the electrode in another example of the secondary battery of this utility model;

[0028] Figure 7 for Figure 6 Enlarged view of region A in the middle;

[0029] Figure 8 for Figure 6 A partial 3D view of a secondary battery;

[0030] Figure 9 This is a partial schematic diagram of one end of the electrode in another example of the secondary battery of this utility model;

[0031] Figure 10 for Figure 9 A bottom view of a secondary battery;

[0032] Figure 11 for Figure 9 A partial 3D view of a secondary battery;

[0033] Figure 12 A partial schematic diagram of one end of the electrode post in another example of the secondary battery of this utility model;

[0034] Figure 13 for Figure 12 A partial 3D view of a secondary battery;

[0035] Figure 14 A partial schematic diagram of one end of the electrode post in another example of the secondary battery of this utility model;

[0036] Figure 15 for Figure 14 A magnified view of a secondary battery.

[0037] Figure 16 A partial schematic diagram of one end of the electrode post in another example of the secondary battery of this utility model;

[0038] Figure 17 for Figure 16 A magnified view of a secondary battery.

[0039] Figure 18 This is a schematic diagram of an example of the battery module of this utility model.

[0040] Figure 19 This is a schematic diagram of an example of the electronic device of this utility model.

[0041] Component designation explanation:

[0042] 1. Electronic device; 10. Battery pack; 11. Working part; 101. Housing; 102. Cover; 100. Secondary battery; 110. Shell; 111. End wall; 1111. Terminal hole; 112. Side wall; 113. Opening; 120. Electrode assembly; 121. Positive electrode; 1211. Positive current collector; 1212. First coated area; 1213. First uncoated area; 122. Separator; 123. Negative electrode; 1231. Negative current collector; 1232. Second coated area; 1233. Second uncoated area; 124. Negative electrode tab; 125. Positive electrode tab; 130. Cover plate; 140, pole post; 141, riveted flange; 1411, outer wall surface; 1412, riveted deformation protrusion; 1413, reinforcing part; 1414, inner wall surface; 14131, recess; 14132, first groove; 14133, second groove; 14134, reinforcing rib; 1415, protrusion; 142, column; 143, outer flange; 144, partition plate; 150, sealing element; 160, gasket; 161, through hole; 162, groove; 1621, first groove segment; 1622, second groove segment; 170, upper insulating element; 180, current collecting component; 190, lower insulating element. Detailed Implementation

[0043] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. It should also be understood that the terminology used in the embodiments of this utility model is for describing specific implementation schemes and not for limiting the scope of protection of this utility model. Test methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or according to the conditions recommended by the respective manufacturers.

[0044] When numerical ranges are given in the embodiments, it should be understood that, unless otherwise specified in this invention, both endpoints of each numerical range and any value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used in this invention, as well as the prior art known to those skilled in the art and the description of this invention, may be implemented using any prior art methods, equipment, and materials similar to or equivalent to those in the embodiments of this invention.

[0045] It should be noted that the terms such as "upper", "lower", "left", "right", "middle" and "one" used in this specification are only for clarity of description and are not intended to limit the scope of implementation of this utility model. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered as within the scope of implementation of this utility model.

[0046] A secondary battery includes an electrode assembly, which is the component in a secondary battery where electrochemical reactions occur, and may contain one or more electrode assemblies.

[0047] The secondary battery also includes a casing, a cover plate, and terminals. The casing includes an end wall and a side wall surrounding the end wall. One end of the side wall has an opening. The electrode assembly can be assembled into the casing through the opening of the casing. The cover plate is used to close the opening of the casing to achieve a seal. The terminals pass through the end wall and are electrically connected to the electrode assembly to conduct the electrical energy generated by the electrode assembly.

[0048] To reduce the risk of leakage between the terminal and the end wall, the terminal is typically riveted to the end wall of the casing, and an insulating and sealing component is used between the terminal and the end wall to achieve sealing and insulation. However, the inventors discovered that during thermal runaway, when high-temperature gas pressure is generated inside the casing, the end wall of the casing warps and deforms, which in turn causes deformation of the bottom of the casing in the terminal flange area, resulting in the terminal flying out of the terminal hole in the casing. After the terminal flies out, on the one hand, charged / conductive materials burning inside the cell can further fly out from the terminal hole, leading to system-level thermal runaway; on the other hand, the terminal itself is conductive, and after flying out, it can easily make contact with the positive and negative terminals of the system / other secondary batteries, also posing a risk of system-level thermal runaway.

[0049] In view of this, please refer to Figures 1 to 17 This utility model provides a solution for a secondary battery 100. This solution strengthens the riveting flange 141 of the terminal post 140 by providing a reinforcing part 1413. When the high temperature and pressure generated inside the casing 110 of the secondary battery 100 cause the end wall 111 of the casing 110 to warp and deform, the reinforcing part 1413 can reduce the shrinkage deformation of the riveting flange 141 of the terminal post 140, thereby reducing the probability of the terminal post 140 flying out of the terminal post hole 1111.

[0050] This utility model provides a secondary battery 100, which includes a housing 110, an electrode assembly 120, a terminal post 140, and an insulation and sealing assembly.

[0051] The housing 110 includes an end wall 111 and a side wall 112 surrounding the end wall 111. As long as a stable sealing and electrical connection can be formed, the connection between the end wall 111 and the side wall 112 can be achieved in various ways, such as integral stamping, integral casting, or separate welding. The circumference of the side wall 112 is not limited; it can be cylindrical or prismatic, or it can follow any other closed-loop contour that matches the end wall 111. In this embodiment, the outer edge of the end wall 111 is circular, and the side wall 112 is cylindrical, surrounding the outer edge of the end wall 111, with a circular opening 113 formed at the end of the side wall 112 facing away from the end wall 111. A receiving cavity is formed within the housing 110 formed by the end wall 111 and the side wall 112 to accommodate the electrode assembly 120, electrolyte, and other necessary battery components. Specifically, the diameter of the housing 110 can be determined according to the specific size of the electrode assembly 120, such as 18mm, 21mm, or 46mm. The shell 110 can be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc. In order to prevent the shell 110 from rusting during long-term use, a layer of anti-rust material such as metallic nickel can be plated on the surface of the shell 110.

[0052] Electrode assembly 120 is disposed inside housing 110 and is a component in secondary battery 100 where electrochemical reactions occur. Housing 110 may contain one or more electrode assemblies 120. Electrode assembly 120 includes an electrode sheet and a separator 122, which are wound to form a wound structure. Specifically, in this embodiment, electrode assembly 120 includes a positive electrode sheet 121, a separator 122, and a negative electrode sheet 123 wound around housing 110 axially.

[0053] The positive electrode 121 includes a positive current collector 1211 and a positive active material layer coated on the positive current collector 1211. A first coated area 1212 coated with the positive active material layer and a first uncoated area 1213 uncoated with the positive active material layer are formed on the positive current collector 1211. The first coated area 1212 and the first uncoated area 1213 are arranged along the axial direction of the housing 110. The first uncoated area 1213 extends to one end of the secondary battery 100 in the height direction to the outside of the separator 122 and is bent towards the axis of the housing 110 to form a stacked positive electrode tab 125.

[0054] The negative electrode 123 includes a negative current collector 1231 and a negative active material layer coated on the negative current collector 1231. A second coated area 1232 coated with the negative active material layer and a second uncoated area 1233 uncoated with the negative active material layer are formed on the negative current collector 1231. The second coated area 1232 and the second uncoated area 1233 are arranged along the axial direction of the housing 110. The second uncoated area 1233 extends to the other end of the secondary battery 100 in the height direction to the outside of the separator 122 and is bent towards the axis of the housing 110 to form a stacked negative electrode tab 124.

[0055] A separator 122 is disposed between the positive electrode 121 and the negative electrode 123 to isolate the positive and negative active material layers. Taking a lithium-ion secondary battery 100 as an example, the positive current collector 1211 can be made of aluminum, and the positive active material layer includes positive active material, which can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative current collector 1231 can be made of copper, and the negative active material layer includes negative active material, which can be carbon or silicon, etc. The substrate material of the separator 122 can be polypropylene (PP) or polyethylene (PE), etc. To protect and insulate the battery cell, an insulating film can also be wrapped around the outside of the battery cell. The insulating film can be synthesized from PP, PE, polyethylene terephthalate (PET), polyvinyl chloride (PVC), or other polymer materials.

[0056] Please refer to Figures 1 and 2. Further, in this invention, the positive electrode tab 125 faces either the end wall 111 or the opening 113, while the negative electrode tab 124 faces the other end of the housing 110. In this embodiment, the positive electrode tab 125 faces the end wall 111 and is electrically connected to the terminal post 140, making the terminal post 140 positively charged. The negative electrode tab 124 faces the opening 113, and the housing 110 is electrically connected to the negative electrode tab 124, thus becoming negatively charged. However, in another embodiment, the negative electrode tab 124 can be connected to the terminal post 140, and the positive electrode tab 125 can be connected to the housing 110.

[0057] The cover plate 130 is sealed and installed on the opening 113; the outer edge shape of the cover plate 130 corresponds to the shape of the opening 113 and is connected to the side wall 112 to seal the opening 113. The installation method of the cover plate 130 includes, but is not limited to, mechanical seal or welding seal. In this embodiment, the cover plate 130 is sealed and plugged on the opening 113 by means of mechanical seal.

[0058] An electrode post hole 1111 is provided on the end wall 111. The electrode post 140 is riveted and installed in the electrode post hole 1111 and is insulated and sealed to the end wall 111 through an insulating sealing assembly. The end of the electrode post 140 facing the electrode assembly 120 passes through the end wall 111 and is directly electrically connected to the positive electrode tab 125 or indirectly connected via a current collector 180. In this embodiment, the electrode post 140 is connected to the positive electrode tab 125 via the current collector 180. The structure of the electrode post 140 can be any suitable form that can be riveted to the end wall 111 and electrically connected to the positive electrode tab 125 of the electrode assembly 120. For example, the cross-section can be circular, square, prismatic, or an irregular contour that can achieve stable conductivity. The shape of the electrode post hole 1111 corresponds to the shape of the electrode post 140. In this embodiment, the electrode post 140 is a rotating body structure, which is beneficial for installation and sealing.

[0059] Please see Figure 3 The pole post 140 includes a pole body 142, an outer flange 143, and a riveting flange 141. The pole body 142 passes through the pole post hole 1111. The cross-section of the pole body 142 can be circular, square, prismatic, or other irregular contours that can achieve riveting and stable conductivity. Considering the better sealing and fitting effect, preferably, the pole body 142 is adapted to the pole post hole 1111, that is, the shape of the pole post hole 1111 corresponds to that of the pole body 142. In this embodiment, the outer contour cross-section of the pole body 142 is circular. The circular design facilitates processing, assembly, and sealing.

[0060] The outer flange 143 is connected to the end of the column 142 located outside the end wall 111 and extends radially along the end wall 111 to stop outside the pole hole 1111. The cross-section of the outer flange 143 can be circular, square, prismatic, or other irregular contours that can achieve stable conductivity, and there is no limitation thereto. The riveting flange 141 is located inside the housing 110 and, under the action of the riveting device, extends and deforms from the column 142 toward the outer periphery of the end wall 111, and is directly or indirectly pressed onto the lower insulating member 190. Specifically, the riveting flange 141 is connected to the end of the column 142 located inside the housing 110 and extends along the side of the end wall 111 facing the inside of the housing 110 toward the outer edge of the end wall 111. The cross-section of the riveting flange 141 can be circular, square, prismatic, or other irregular contours that can achieve riveting deformation, and there is no limitation thereto.

[0061] The insulating sealing assembly includes a seal 150, which surrounds the post 142 and is at least partially sandwiched between the outer flange 143 and the end wall 111. The shape of the seal 150 and its position between the post 140 and the end wall 111 are not limited. In this embodiment, the seal 150 is an annular sealing ring with a rectangular cross-section. A portion of the seal 150 near the outer ring is sandwiched between the outer flange 143 and the end wall 111, while a portion near the inner ring is located between the lower insulating member 190 and the outer flange 143. The seal 150 is an elastic element with a certain compressibility and is capable of sealing between the outer flange 143 and the end wall 111 to prevent leakage between the post 140 and the end wall 111. The material of the seal 150 can be EPDM rubber, fluorosilicone rubber, or fluororubber, but is not limited to these.

[0062] The insulating sealing assembly also includes an upper insulating member 170 and a lower insulating member 190. A portion of the upper insulating member 170 is press-fitted between the outer flange 143 and the end wall 111, and a portion surrounds the periphery of the outer flange 143, thereby providing insulating support between the outer flange 143 and the end wall 111. The inner ring of the lower insulating member 190 is press-fitted between the riveted flange 141 and the end wall 111, and the outer ring of the lower insulating member 190 extends beyond the riveted flange 141 and is positioned between the electrode assembly 120 (or the current collector 180) and the end wall 111. The materials of the upper insulating member 170 and the lower insulating member 190 can be any one of PP, polyphenylene sulfide (PPS), polycarbonate (PC), soluble polytetrafluoroethylene (PFA), polybutylene terephthalate (PBT), and liquid crystal polymer (LCP), but are not limited to these.

[0063] The terminal post 140 also includes a reinforcing portion 1413, which is at least partially located on the riveting flange 141 and configured to prevent the riveting flange 141 from shrinking and deforming. By providing the reinforcing portion 1413, the riveting flange 141 can be strengthened. When high temperature and pressure are generated inside the casing 110 of the secondary battery 100, causing the end wall 111 of the casing 110 to warp and deform, the probability of the riveting flange 141 of the terminal post 140 shrinking and deforming and flying out from the terminal post hole 1111 can be reduced.

[0064] Please see Figures 3 to 5In one embodiment of the secondary battery 100 of this utility model, the reinforcing part 1413 includes a partially upsetting recess 14131. The recess 14131 is disposed on the side of the riveting flange 141 facing away from the end wall 111 and is recessed into the riveting flange. As long as it can strengthen the riveting flange 141 and prevent the riveting flange 141 from shrinking and deforming, the shape and position of the recess 14131 are not limited. Similar to the mechanism of work hardening, by providing a partially upsetting recess 14131 on the riveting flange 141, the dislocation movement inside the material can be increased. When the material is subjected to external force and undergoes plastic deformation, dislocations will move and multiply inside the crystal. As the recess 14131 deforms, the mutual entanglement and obstruction between dislocations will increase, making the movement of dislocations more difficult, thereby increasing the hardness and strength of the riveting flange 141 and providing additional support and constraint for the riveting flange 141.

[0065] Considering that a shallow recess 14131 may not provide sufficient support and restraint, while a deep recess 14131 may cause stress concentration or even cracks in the riveting flange 141 during riveting, please refer to [reference needed]. Figure 3 In one embodiment of the secondary battery 100 of this utility model, the recess depth of the recess 14131 is 1 / 3 to 1 / 2 of the maximum thickness H1 of the riveting flange 141 at the corresponding position of the recess 14131. Specifically, the depth of the recess 14131 can be 1 / 3H1, 1 / 2H1, or any value between the two. Setting the recess depth of the recess 14131 to 1 / 3H1 to 1 / 2H1 of the maximum thickness of the riveting flange 141 is a dimensional design that has been precisely calculated and experimentally verified. The depth ratio of 1 / 3H1 to 1 / 2H1 can ensure that the recess 14131 provides effective support for the flange during riveting, reducing shrinkage deformation, without damaging the structural integrity of the riveting flange 141, thereby better achieving the purpose of preventing the terminal post 140 from flying out.

[0066] In one embodiment of the secondary battery 100 of this utility model, the riveting flange includes a riveting deformation protrusion 1412 furthest from the end wall 111. The position of the riveting deformation protrusion 1412 corresponds to the maximum thickness position of the riveting flange 141 (i.e., the distance from the top of the riveting deformation protrusion 1412 on the side away from the end wall 111 to the contact surface between the riveting flange 141 and the lower insulating member 190 is the maximum thickness H1). The riveting deformation protrusion 1412 surrounds the outer periphery of the column 142 and is formed by the flow of material during the riveting process. The recess 14131 extends from the outside of the riveting deformation protrusion 1412 to the inside of the riveting deformation protrusion 1412. The width t of the recess 14131 should not exceed 5 mm, and the length m of the recess 14131 should not exceed 3 mm. As the area where the flange deformation is most significant during the riveting process, the riveting deformation protrusion 1412 becomes a key part of the connection strength. The recess 14131 extends from the outside to the inside of the riveting deformation protrusion 1412. This through-type structural design can better guide and control the deformation direction and degree of the riveting flange 141 during riveting, making the deformation more uniform and controllable. At the same time, limiting the width and length of the recess 14131 to a small range (width ≤ 5mm, length ≤ 3mm) can avoid the recess 14131 being too large and weakening the overall structural strength of the flange. This ensures that while reducing shrinkage deformation, sufficient connection strength is maintained between the flange and the pole post 140, effectively preventing the pole post 140 from flying out.

[0067] Please see Figures 6 to 8 In one embodiment of the secondary battery 100 of this utility model, the riveting flange 141 also includes a riveting deformation protrusion 1412 furthest from the end wall 111, and the riveting deformation protrusion 1412 surrounds the outer periphery of the column 142; and Figures 3 to 5Unlike the recess 14131 in the previous embodiment, in this embodiment, the recess 14131 includes a first groove 14132 and a second groove 14133. The first groove 14132 and the second groove 14133 are interconnected, forming an approximately X-shaped recessed structure. Both the first groove 14132 and the second groove 14133 extend from the outside of the riveting deformation protrusion 1412 to the inside of the riveting deformation protrusion 1412. The interconnected first groove 14132 and the second groove 14133 form an approximately mesh-like recessed structure, which can constrain and support the flange from multiple directions during the riveting process. Compared with a single groove 162, the intersecting groove 162 can more effectively disperse the stress generated during riveting, and the dislocation movement of the material within the intersecting groove 162 will proceed in multiple directions, thereby significantly improving the flange's resistance to shrinkage deformation. At the same time, this multi-directional constraint also enhances the connection stability between the flange and the terminal post 140, making it more difficult for the terminal post 140 to fly out of the terminal post hole 1111 when subjected to various external forces (such as vibration, impact, etc.), further improving the reliability and safety of the battery.

[0068] Please see Figures 9 to 11 In one embodiment of the secondary battery 100 of this utility model, the reinforcing part 1413 includes a locally thickened reinforcing rib 14134. The reinforcing rib 14134 is disposed on the side of the riveting flange 141 facing away from the end wall 111, and is at least partially located on the riveting flange. By providing a locally thickened reinforcing rib 14134 on the riveting flange 141, the local strength and rigidity of the flange within the riveting flange 141 can be significantly improved. The presence of the reinforcing rib 14134 allows the flange to better resist the tendency of shrinkage deformation during the riveting process, maintaining the stability of its shape. At the same time, since the reinforcing rib 14134 is at least partially located within the riveting flange, it forms a mutually interlocking structure with the riveting flange 141 after riveting deformation, enhancing the tightness of the connection between the flange and the terminal post 140, thereby effectively preventing the terminal post 140 from flying out of the terminal post hole 1111 during use, ensuring the stable operation of the battery.

[0069] Please see Figures 12 to 13In one embodiment of the secondary battery 100 of this utility model, the column 142 is a cylindrical structure, the cylindrical structure includes an inner wall surface 1414, and the riveting flange 141 includes an outer wall surface 1411 on the side opposite to the end wall 111. The outer wall surface 1411 is connected to the inner wall surface 1414. One end of the reinforcing rib 14134 is located on the inner wall surface 1414, and the other end extends along the inner wall surface 1414 to the outer wall surface 1411. This design of the reinforcing rib 14134 extending from the inner wall surface 1414 of the column 142 to the outer wall surface 1411 of the riveting flange 141 forms a continuous reinforcing structure. During the riveting process, the reinforcing rib 14134 can tightly connect the column 142 and the riveting flange 141 together, making the force transmission between the two smoother and more uniform. This design not only improves the deformation resistance of the flange and reduces shrinkage deformation, but also enhances the structural stability of the entire riveting area, effectively preventing the terminal post 140 from flying out of the terminal post hole 1111 when subjected to external force, thus improving the reliability and durability of the battery.

[0070] Please see Figure 1 and Figures 12 to 13 In one embodiment of the secondary battery 100 of this utility model, the column 142 includes a separator 144, which is typically used for welding connection with the current collector 180. The separator 144 is located inside the cylindrical structure, and its outer periphery is integrally connected to the inner wall surface 1414. One end of the reinforcing rib 14134 is connected to the separator 144, and the other end of the reinforcing rib 14134 extends to the outer periphery of the riveted flange 141. The connection between the separator 144 and the reinforcing rib 14134 forms a synergistic reinforcement mechanism. The reinforcing rib 14134 extends from the separator 144 to the outer periphery of the riveted flange 141, effectively integrating the structural strength inside the column 142 with the strength of the outer flange. During the riveting process, this design can better resist the shrinkage deformation of the flange, while uniformly transmitting the force generated by riveting to the inside of the column 142, avoiding excessive local stress that could cause the electrode post 140 to loosen or fly out.

[0071] Please see Figures 12 to 13In one embodiment of the secondary battery 100 of this utility model, the width of the reinforcing rib 14134 gradually increases along the direction extending from the inner wall surface 1414 to the outer wall surface 1411. This gradual widening of the reinforcing rib 14134 is an optimized structural layout. At the end near the inner wall surface of the column 142, the reinforcing rib 14134 is relatively narrow, which reduces the space occupied inside the column 142 and ensures the compactness of the battery's internal structure. As it extends towards the outer wall surface of the riveting flange 141, the width of the reinforcing rib 14134 gradually increases, better adapting to the deformation requirements of the flange during riveting and providing broader support and constraint. This gradual width design allows the reinforcing rib 14134 to exert its optimal reinforcing effect at different positions, effectively reducing the shrinkage deformation of the flange, enhancing the connection strength between the flange and the terminal post 140, preventing the terminal post 140 from flying out, and simultaneously ensuring the rational utilization of the battery's internal space.

[0072] In one embodiment of the secondary battery 100 of this utility model, the height H2 of the reinforcing rib 14134 protruding from the riveting flange 141 is ≥0.2mm, the maximum width of the reinforcing rib 14134 is ≤5mm, and the maximum length of the reinforcing rib 14134 is ≤3mm. Precisely limiting the dimensions of the reinforcing rib 14134 is to ensure optimal performance in reducing shrinkage deformation of the riveting flange 141 and preventing the terminal post 140 from flying out. A protrusion height ≥0.2mm ensures sufficient height to provide effective support and constraint, preventing excessive deformation of the flange during riveting. The restrictions of a maximum width ≤5mm and a maximum length ≤3mm prevent the reinforcing rib 14134 from being too large and adversely affecting the structural strength of the riveting flange 141 and the internal space of the battery. These dimensional parameters are ranges derived from extensive experiments and practical verification, achieving structural rationality and compactness while ensuring the function of the reinforcing rib 14134.

[0073] In one embodiment of the secondary battery 100 of this utility model, the maximum thickness H1 of the riveted flange 141 should not exceed 1.2 mm (see...). Figure 3The lower limit of the maximum thickness H1 of the riveting flange 141 can be selected according to the riveting strength requirements. Limiting the maximum thickness of the riveting flange 141 to within 1.2 mm is a design that comprehensively considers the flange strength, riveting performance, and the overall size and weight of the battery. A thinner riveting flange 141 is more likely to produce uniform deformation during the riveting process, which helps reduce the degree of shrinkage deformation. At the same time, appropriately reducing the flange thickness can reduce the overall weight of the battery and increase energy density. However, an excessively thin flange may lead to insufficient strength. Therefore, the maximum thickness limit of 1.2 mm is the optimal balance point between ensuring sufficient flange strength and good riveting performance, helping to achieve the goals of reducing shrinkage deformation of the riveting flange 141 and preventing the terminal post 140 from flying out.

[0074] In one embodiment of the secondary battery 100 of this utility model, the riveting flange 141 includes a plurality of recesses 14131, the number of recesses 14131 being ≥4. The column 142 is cylindrical, and the plurality of recesses 14131 are evenly distributed circumferentially on the riveting flange 141 with the center of the column 142 as the center. Providing a plurality of recesses 14131 evenly distributed circumferentially ensures that the flange is subjected to more uniform force in all directions during the riveting process, avoiding uneven deformation or loosening of the terminal post 140 caused by local stress concentration. The ≥4 number of recesses 14131 ensures sufficient support and constraint throughout the entire circumference of the column 142, reducing the shrinkage deformation of the riveting flange 141. Simultaneously, this evenly distributed structural design also improves the symmetry and stability of the connection between the flange and the terminal post 140, making it less likely for the terminal post 140 to fly out of the terminal post hole 1111 when subjected to external forces in all directions, thus enhancing the battery's reliability and vibration resistance.

[0075] In one embodiment of the secondary battery 100 of this utility model, the plurality of recesses 14131 are centrally symmetrical about the center of the terminal post 140, with each pair corresponding to the other. This centrally symmetrical arrangement of the recesses 14131 further optimizes the uniformity of force distribution on the flange. During the riveting process, the symmetrical recesses 14131 balance the forces acting on the flange in opposite directions, preventing deformation or displacement of the terminal post 140 due to uneven force distribution. This symmetrical design not only helps reduce the shrinkage deformation of the riveted flange 141 but also ensures the stable position of the terminal post 140 within the terminal post hole 1111, preventing it from flying out during use due to unbalanced force distribution, thus improving the stability and safety of the battery.

[0076] Please see Figures 14 to 15In another embodiment of the secondary battery 100 of this utility model, a portion of the lower insulating member 190 is disposed between the riveting flange 141 and the end wall 111. The secondary battery 100 also includes a gasket 160, which is disposed between the lower insulating member 190 and the riveting flange 141. The gasket 160 is provided with a clearance structure for the riveting flange 141 to deform and enter during the riveting process. The gasket 160 and its clearance structure provide reasonable space and guidance for the deformation of the riveting flange 141 during the riveting process. During riveting, a portion of the flange enters the clearance structure, which effectively controls the direction and degree of flange deformation, allowing it to deform in a predetermined manner, thereby reducing shrinkage deformation. At the same time, the presence of the gasket 160 also plays a buffering and protective role, preventing excessive friction or damage caused by direct contact between the flange and the lower insulating member 190, further ensuring the riveting quality and preventing the terminal post 140 from flying off due to unstable connection during subsequent use. Furthermore, the protrusion 1415 of the riveting flange 141 entering the relief structure can strengthen the gripping force between the riveting flange 141 and the gasket 160, enabling them to work together to improve the riveting flange 141's resistance to shrinkage deformation. It should be noted that if the reinforcing part is a partially upsetting recess, the recess can also correspond to the relief structure on the gasket. In this way, the material at the corresponding position of the recess can flow into the relief structure, thereby combining the recess and the relief structure to achieve a more powerful reinforcement of the riveting flange 141.

[0077] In one embodiment of the secondary battery 100 of this utility model, the clearance structure includes a through hole 161. The through hole 161 penetrates the gasket 160 along the thickness direction of the gasket 160. The diameter of the through hole 161 is ≥0.2mm, and the maximum diameter value of the through hole 161 can be selected according to design requirements. The number of through holes 161 can be one, two, or more. In this embodiment, the number of through holes is greater than or equal to four, and they are evenly distributed along the circumference. As a form of clearance structure, the through hole 161 provides a direct channel for the deformation of the riveting flange 141. The setting of the through hole 161 diameter ≥0.2mm ensures that the flange has sufficient space to enter during the riveting process, avoiding excessive stress concentration caused by insufficient space hindering flange deformation. This design allows the riveting flange 141 to deform smoothly in the expected manner, reducing shrinkage deformation while ensuring the tightness of the connection after riveting, effectively preventing the terminal post 140 from flying out of the terminal post hole 1111, and improving the assembly quality and reliability of the battery.

[0078] In one embodiment of the secondary battery 100 of this utility model, the avoidance structure includes a groove 162, which includes a first groove segment 1621 and a second groove segment 1622. The first groove segment 1621 and the second groove segment 1622 are coaxially arranged cylindrical grooves. One end of the first groove segment 1621 penetrates the contact surface between the gasket 160 and the riveting flange 141, and the other end of the first groove segment 1621 extends away from the riveting flange 141 and communicates with the second groove segment 1622. The cross-sectional area of ​​the first groove segment 1621 is smaller than the cross-sectional area of ​​the second groove segment 1622, thereby forming a stepped groove shape. This groove 162 structure design provides more flexible and precise guidance for the deformation of the riveting flange 141. The first groove 1621 penetrates the contact surface between the gasket 160 and the riveting flange 141, allowing the riveting flange 141 to smoothly enter the groove 162 during the initial riveting stage. The second groove 1622 provides more space for further deformation of the riveting flange 141. The design that the cross-sectional area of ​​the first groove 1621 is smaller than that of the second groove 1622 allows the riveting flange 141 to form a larger diameter protrusion in the second groove 1622. When the riveting flange 141 has a tendency to shrink, the larger diameter protrusion 1415 in the second groove 1622 can stop it from the first groove 1621, thereby preventing the riveting flange 141 from lifting and enhancing the connection strength between the flange and the pole post 140.

[0079] Please see Figure 18 This utility model also provides a battery pack 10, which includes the secondary battery 100 described above. In one embodiment of the battery pack 10, the battery pack 10 includes a housing 101, a cover 102, and multiple secondary batteries 100. The multiple secondary batteries 100 are placed in the housing 101 and are connected in series or parallel, or a combination of series and parallel connections. The cover 102 covers the housing 101 to protect the multiple secondary batteries 100. It should be noted that, in addition to the secondary battery 100 of this utility model, the battery pack 10 may also include a battery pack thermal management system, circuit board, etc. The battery pack 10 can be a battery module, a battery pack, an energy storage cabinet, etc.; these will not be described in detail here.

[0080] Please see Figure 19This utility model also provides an electronic device 1, which includes the aforementioned battery pack 10. A working part 11 is electrically connected to the battery pack 10 to obtain electrical power. As an example, the electronic device 1 is a vehicle, which can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, but are not limited thereto. The working part 11 is the vehicle body, and the battery pack 10 is located at the bottom of the vehicle body, providing electrical power for the vehicle's operation or the operation of its internal electrical components. However, in other embodiments, the electronic device 1 can also be a mobile phone, portable device, laptop computer, ship, spacecraft, electric toy, and power tool, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc.; the working part 11 can be a unit component capable of obtaining electrical power from the battery pack 10 and performing corresponding work, such as a fan blade rotation unit or a vacuum cleaner suction unit. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric boat toys, and electric airplane toys, etc.; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application does not impose any special limitations on the aforementioned electronic device 1.

[0081] This utility model of a secondary battery strengthens the riveting flange near the post by providing a reinforcing part. This reduces the probability of the riveting flange shrinking and deforming and flying out of the post hole when high-temperature gas pressure causes warping deformation of the battery casing. Therefore, this utility model effectively overcomes some practical problems in the prior art, thus having high utilization value and practical significance. The above embodiments are merely illustrative of the principle and effect of this utility model and are not intended to limit it. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A secondary battery, characterized in that, include: The housing includes an end wall, on which a pole hole is provided; The pole is riveted and fixed in the pole hole, and includes a pole body and a riveting flange. The pole body passes through the pole hole, and the riveting flange is disposed in the housing and connected to the pole body. An insulating sealing assembly is disposed between the pole post and the end wall, thereby sealing and insulating the pole post from the end wall; An electrode assembly is installed inside the housing and is electrically connected to the electrode post and the housing; The pole post further includes a reinforcing portion, which is at least partially located on the riveted flange and is configured to prevent the riveted flange from shrinking and deforming.

2. The secondary battery according to claim 1, characterized in that, The reinforcing part includes a partially pressed recess, which is located on the side of the riveted flange away from the end wall.

3. The secondary battery according to claim 2, characterized in that, The depth of the recess is 1 / 3 to 1 / 2 of the maximum thickness of the riveted flange.

4. The secondary battery according to claim 2, characterized in that, The riveting flange includes a riveting deformation protrusion furthest from the end wall, the riveting deformation protrusion surrounds the outer periphery of the column, and the recess extends from the outside of the riveting deformation protrusion to the inside of the riveting deformation protrusion.

5. The secondary battery according to claim 2, characterized in that, The riveting flange includes a riveting deformation protrusion furthest from the end wall, which surrounds the outer periphery of the column; the recess includes a first groove and a second groove, which are intersecting and communicating with each other, and the first groove and the second groove extend from the outside of the riveting deformation protrusion to the inside of the riveting deformation protrusion.

6. The secondary battery according to claim 1, characterized in that, The reinforcing part includes a locally thickened reinforcing rib, which is disposed on the side of the riveting flange away from the end wall and is at least partially located within the riveting flange.

7. The secondary battery according to claim 6, characterized in that, The column is a cylindrical structure, the cylindrical structure includes an inner wall surface, the riveted flange includes an outer wall surface on the side opposite to the end wall, the outer wall surface is connected to the inner wall surface, one end of the reinforcing rib is located on the inner wall surface, and the other end extends along the inner wall surface to the outer wall surface.

8. The secondary battery according to claim 7, characterized in that, The column includes a partition located inside the cylindrical structure. One end of the reinforcing rib is connected to the partition, and the other end of the reinforcing rib extends to the outer periphery of the riveted flange.

9. The secondary battery according to claim 7, characterized in that, The width of the reinforcing rib gradually increases along the direction extending from the inner wall surface to the outer wall surface.

10. The secondary battery according to any one of claims 2 to 5, characterized in that, The riveting flange includes a plurality of recesses, the number of which is ≥4, and the plurality of recesses are evenly distributed circumferentially on the riveting flange with the center of the column as the center.

11. The secondary battery according to any one of claims 2 to 5, characterized in that, There are multiple recesses, and the multiple recesses are paired up and are centrally symmetrical about the center of the pole post.

12. The secondary battery according to any one of claims 1 to 9, characterized in that, The insulating sealing assembly includes a lower insulating member, a portion of which is disposed between the riveting flange and the end wall. The secondary battery also includes a gasket, which is disposed between the lower insulating member and the riveting flange. The gasket has an avoidance structure that allows the riveting flange to deform and enter during the riveting process.

13. The secondary battery according to claim 12, characterized in that, The clearance structure includes a through hole that penetrates the gasket along its thickness direction.

14. The secondary battery according to claim 12, characterized in that, The avoidance structure includes a groove, which includes a first groove segment and a second groove segment. One end of the first groove segment passes through the contact surface between the gasket and the riveting flange, and the other end of the first groove segment extends away from the riveting flange and communicates with the second groove segment. The cross-sectional area of ​​the first groove segment is smaller than the cross-sectional area of ​​the second groove segment.

15. A battery pack, characterized in that, The secondary battery includes any one of claims 1 to 14.

16. An electronic device, characterized in that, Includes the battery pack as described in claim 15.

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