Top cover assembly and battery

Abstract

This utility model discloses a top cover assembly and a battery. The top cover assembly includes a top cover sheet, a terminal post, and an upper plastic layer. The top cover sheet includes a first plate and an enclosing portion. The enclosing portion is connected to the first plate to form a mounting groove, and a first limiting portion is provided in the mounting groove. The enclosing portion includes a first section and a second section. The second section is an annular structure with a uniform wall thickness. At least a portion of the terminal post is disposed in the mounting groove, and the terminal post is provided with a second limiting portion. At least a portion of the upper plastic layer is disposed between the terminal post and the first section. The upper plastic layer has a third limiting portion and a fourth limiting portion. The third limiting portion and the first limiting portion are circumferentially limitingly fitted, and the fourth limiting portion and the second limiting portion are circumferentially limitingly fitted. In this utility model, the enclosing portion separates the limiting function from the riveting processing area through layering. The second section maintains an annular structure with a uniform wall thickness, which avoids material accumulation or thinning during riveting processing, improves the uniformity of the extrusion pressure distribution along the outer periphery of the terminal post, and thus ensures sealing performance.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a top cover assembly and a battery. Background Technology

[0002] In related technologies, in order to prevent twisting and misalignment between the upper plastic and the top cover plate, a vertical through groove is usually set on the side wall of the pole hole of the top cover plate to prevent twisting. Due to the uneven thickness of the side wall, during riveting, the uneven thickness of the side wall will cause material extrusion after bending, resulting in uneven distribution of axial force in the outer circumferential direction of the pole, which affects the sealing performance. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a top cover assembly that can improve the uniformity of the extrusion pressure distribution along the outer periphery of the pole, thereby ensuring sealing performance.

[0004] This utility model also proposes a battery having the above-mentioned top cover assembly.

[0005] In a first aspect, embodiments of this application provide a top cover assembly, comprising:

[0006] The top cover plate includes a first plate and an enclosing portion, the enclosing portion being connected to the first plate to enclose and form a mounting groove, the mounting groove being provided with a first limiting portion; the enclosing portion includes a first section and a second section, the first section being connected to the first plate and the second section, the second section being an annular structure with a uniform wall thickness;

[0007] The pole post, at least a portion of which is disposed within the mounting groove, is provided with a second limiting portion;

[0008] The upper plastic, at least partially disposed between the pole post and the first segment, has a third limiting part and a fourth limiting part. The third limiting part cooperates with the first limiting part to limit the relative rotation of the upper plastic and the pole post, and the fourth limiting part cooperates with the second limiting part to limit the relative rotation of the upper plastic and the top cover plate.

[0009] The top cover assembly according to the embodiments of this utility model has at least the following beneficial effects: the top cover sheet is divided into a first section and a second section, that is, the top cover sheet separates the limiting function from the riveting processing area through a layered structural design. A first limiting part is provided on the first section, which cooperates with a third limiting part of the upper plastic to form a first anti-torsion structure. A second limiting part is provided on the pole post, which cooperates with a fourth limiting part of the upper plastic to form a second anti-torsion structure. This double limiting structure can disperse the torque load. Furthermore, the second section maintains a uniform wall thickness annular structure, avoiding material accumulation or thinning during riveting processing, improving the uniformity of the extrusion pressure distribution along the outer periphery of the pole post, thereby ensuring sealing performance.

[0010] According to the first aspect, in one possible implementation, the first limiting portion connects the first segment and the first plate; and / or,

[0011] The first limiting part is gradually widened along the direction close to the bottom wall of the mounting groove.

[0012] According to the first aspect, in one possible implementation, the pole post includes a main body and an outer ring portion disposed on the outside of the main body;

[0013] The second limiting part is provided on the side wall of the main body or the side wall of the outer ring part;

[0014] Alternatively, the second limiting portion may be located on the top surface of the outer ring portion.

[0015] According to the first aspect, in one possible implementation, the second limiting portion is disposed on the side wall of the outer ring portion, and the first limiting portion and the second limiting portion are offset along the outer periphery of the pole post.

[0016] According to the first aspect, in one possible implementation, the second limiting portion includes a second limiting protrusion disposed on the top surface or side wall of the outer ring portion;

[0017] Alternatively, the second limiting portion includes a limiting groove provided on the top surface of the outer ring portion, the depth of the limiting groove being less than the thickness of the outer ring portion.

[0018] According to the first aspect, in one possible implementation, the upper plastic has a first end and a second end, the first end being away from the first plate body relative to the second end, and the first end being located outside the mounting groove;

[0019] Wherein, the second end is located between the pole post and the first section, and there is a gap between the second end and the bottom wall of the mounting groove;

[0020] Alternatively, the second end is connected to the bottom wall, and the second end of the upper plastic extends between the pole and the bottom wall of the mounting groove.

[0021] According to the first aspect, in one possible implementation, the second end of the upper plastic has a first limiting groove, and the top cover assembly further includes a sealing ring, the sealing ring including an annular body and a sealing protrusion, the annular body being disposed between the pole post and the bottom wall of the mounting groove, the sealing protrusion being connected to the outer side wall of the annular body, and the sealing protrusion extending into the first limiting groove.

[0022] According to the first aspect, in one possible implementation, the upper plastic covers the outside of the pole post, and the second section presses against the upper plastic;

[0023] Alternatively, the upper plastic coating covers the inner walls of the first and second sections facing the mounting groove, with the upper plastic coating on the second section pressing against the pole post.

[0024] According to the first aspect, in one possible implementation, the first plate body includes a first region and a second region connected to each other, the first region protruding from or recessed into the second region, and the enclosing portions are all disposed in the first region.

[0025] According to the first aspect, in one possible implementation, the top cover assembly further includes a lower plastic having a hot melt pillar, and the first plate has a hot melt hole, the hot melt hole including a first-order hole and a second-order hole;

[0026] Wherein, the first-order hole has a first wall surface opposite to the opening side of the hot-melt hole, the second-order hole is disposed on the first wall surface, and the depth from the first wall surface to the opening of the hot-melt hole increases gradually from the center to the edge, and the second-order hole gradually widens in a direction away from the first-order hole; and / or,

[0027] The second-order hole has a second wall surface opposite to the opening side of the hot-melt hole. The second wall surface is at least partially structured such that the depth of the opening of the hot-melt hole increases from the center to the edge. The first plate also includes a connecting portion and an anti-detachment portion. The connecting portion connects the second wall surface and the anti-detachment portion. The anti-detachment portion protrudes from the side wall of the connecting portion and there is a gap between the edge of the anti-detachment portion and the opening edge of the hot-melt hole.

[0028] According to the first aspect, in one possible implementation, the top cover assembly further includes a sealing ring disposed between the pole post and the bottom wall of the mounting groove;

[0029] At least one of the pole post and the bottom wall of the mounting groove is provided with a fifth limiting part, which is used to limit the radial movement of the sealing ring. The fifth limiting part is a pressing protrusion or a second limiting groove.

[0030] According to the first aspect, in one possible implementation, the top cover has a third limiting groove located outside the enclosure, and a portion of the upper plastic structure is fixedly connected to the third limiting groove.

[0031] According to the first aspect, in one possible implementation, the upper plastic is configured as an integral structure made of a high-temperature resistant insulating material or a high-temperature resistant conductive material;

[0032] Alternatively, the upper plastic part includes a coating part and a glue injection part. The coating part covers the outer side of the pole post. The coating part is an integral structure made of high-temperature resistant insulating material or high-temperature resistant conductive material. The glue injection part is located between the inner wall of the mounting groove and the coating part.

[0033] Secondly, embodiments of this application also provide a battery, the battery including the top cover assembly described in the first aspect.

[0034] The battery according to the embodiments of this utility model has at least the following beneficial effects: By applying the above-mentioned top cover assembly, the top cover sheet is divided into a first section and a second section, that is, the top cover sheet separates the limiting function from the riveting processing area through a layered structure design. A first limiting part is provided on the first section, which cooperates with a third limiting part of the upper plastic to form a first anti-torsion structure. A second limiting part is provided on the electrode post, which cooperates with a fourth limiting part of the upper plastic to form a second anti-torsion structure. The double limiting structure can disperse the torque load. Furthermore, the second section maintains a uniform wall thickness annular structure, avoiding material accumulation or thinning during riveting processing, improving the uniformity of the extrusion pressure distribution along the outer periphery of the electrode post, thereby ensuring sealing performance.

[0035] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0036] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0037] Figure 1 This is a cross-sectional structural diagram of the top cover assembly in one embodiment of the present invention;

[0038] Figure 2 This is a schematic diagram of the disassembly structure of the top cover assembly in one embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the structure of the second limiting part located on the top surface of the outer ring part in one embodiment of the present invention;

[0040] Figure 4 This is a schematic diagram of the partitioned cross-sectional structure of the top cover sheet in one embodiment of the present invention;

[0041] Figure 5 This is a schematic diagram of the partitioned disassembly structure of the top cover sheet in one embodiment of the present invention;

[0042] Figure 6 This is a schematic diagram of the structure of the upper plastic integral structure in one embodiment of the present invention;

[0043] Figure 7 This is a schematic diagram of the structure of the upper plastic part including the overmolding part and the injection part in one embodiment of the present invention;

[0044] Figure 8 This is a schematic cross-sectional view of the second limiting part located on the outer side of the outer ring part in one embodiment of the present invention;

[0045] Figure 9 This is a schematic diagram of the disassembly structure of the second limiting part located on the outer side of the outer ring part in one embodiment of the present invention;

[0046] Figure 10 This is a schematic diagram of a structure in which the second limiting part is configured in a wavy shape in one embodiment of the present invention;

[0047] Figure 11 This is a schematic diagram of a structure in one embodiment of the present invention, showing that the second limiting part is configured as a limiting rib.

[0048] Figure 12 This is a cross-sectional structural diagram of a second limiting groove provided on the pole post and the top cover plate in one embodiment of the present invention;

[0049] Figure 13 This is a schematic diagram of the disassembly structure of the pole post and the top cover plate having a second limiting groove in one embodiment of the present invention;

[0050] Figure 14 This is a schematic cross-sectional view of the upper plastic extending between the pole post and the bottom wall of the mounting groove in one embodiment of the present invention.

[0051] Figure 15 This is a schematic diagram of the disassembly structure of the upper plastic extending between the pole post and the bottom wall of the mounting groove in one embodiment of the present invention.

[0052] Figure 16 This is a cross-sectional structural diagram of the upper plastic protruding from the second section in one embodiment of the present invention;

[0053] Figure 17 This is a cross-sectional disassembly diagram showing the upper plastic protruding from the second section in one embodiment of the present invention;

[0054] Figure 18 This is a schematic diagram of the structure of the melting hole in one embodiment of the present invention;

[0055] Figure 19 This is a schematic diagram of the structure of the melting hole in another embodiment of the present invention.

[0056] Figure label:

[0057] 100. Top cover plate; 110. First plate; 110a. First zone; 110b. Second zone; 111. Hot melt hole; 1111. First-stage hole; 1112. First wall surface; 1113. Second-stage hole; 1114. Second wall surface; 112. Connecting part; 113. Anti-detachment part; 120. Enclosing part; 121. First section; 122. Second section; 130. Mounting groove; 140. First limiting part; 150. Through hole; 160. Third limiting groove;

[0058] 200, pole post; 210, second limiting part; 211, second limiting protrusion; 212, limiting groove; 220, main body; 230, outer ring part;

[0059] 300, Plastic coating; 301, First end; 302, Second end; 310, Third limiting part; 320, Fourth limiting part; 330, First limiting groove; 341, Overmolding part; 342, Injection part;

[0060] 400. Sealing ring;

[0061] 500, lower plastic part; 510, second plate; 530, snap-fit ​​part; 550, fifth limiting part. Detailed Implementation

[0062] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0063] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0064] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0065] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0066] In the description of this utility model, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0067] In existing technologies, power battery top cover assemblies commonly employ anti-torsion structures on the sidewalls of the terminal holes to prevent relative rotation between the plastic parts and the top cover sheet. These anti-torsion structures are typically located in the sidewall areas requiring riveting, resulting in uneven wall thickness in these areas. During riveting, this uneven wall thickness can easily cause metal material to be squeezed and flowed, leading to material accumulation or thinning in localized areas, which in turn affects the control of the compression deformation of the sealing ring. This processing defect directly results in fluctuations in sealing performance.

[0068] To address the aforementioned problems, this application proposes a top cover assembly. For example... Figures 1 to 3 As shown, in some embodiments, the top cover assembly includes a top cover sheet 100, a pole post 200, and an upper plastic 300. The top cover sheet 100 includes a first plate 110 and an enclosing portion 120. The enclosing portion 120 is connected to the first plate 110 to enclose and form a mounting groove 130. The enclosing portion 120 includes a first segment 121 and a second segment 122. The first segment 121 connects the first plate 110 and the second segment 122. The inner sidewall of the first segment 121 is provided with a first limiting portion 140. The second segment 122 is an annular structure with a uniform wall thickness. At least a portion of the pole post 200 is disposed within the mounting groove 130. The upper plastic 300 is provided with a second limiting part 210; at least a part of the structure of the upper plastic 300 is provided between the pole post 200 and the inner wall of the first section 121. The upper plastic 300 has a third limiting part 310 and a fourth limiting part 320. The third limiting part 310 cooperates with the first limiting part 140 to limit the relative rotation between the upper plastic 300 and the pole post 200. The fourth limiting part 320 cooperates with the second limiting part 210 to limit the relative rotation between the upper plastic 300 and the top cover plate 100.

[0069] In this embodiment, the enclosure portion 120 is divided into a first segment 121 and a second segment 122. The enclosure portion 120 of the top cover 100 separates the limiting function from the riveting processing area through a layered structural design. The first segment 121 has a first limiting portion 140 that cooperates with the third limiting portion 310 of the upper plastic 300 to form a first anti-torsion structure. The pole post 200 has a second limiting portion 210 that cooperates with the fourth limiting portion 320 of the upper plastic 300 to form a second anti-torsion structure. This dual limiting structure can disperse the torque load. Furthermore, the second segment 122 maintains a uniform wall thickness annular structure, preventing material accumulation or thinning during riveting, improving the uniformity of the extrusion pressure distribution along the outer periphery of the pole post 200, thereby ensuring sealing performance.

[0070] The inner wall of the mounting groove 130 is formed by the enclosure portion 120 and a portion of the first plate 110. Specifically, the first section 121 of the enclosure portion 120 forms the side wall of the mounting groove 130, and a portion of the first plate 110 forms the bottom wall of the mounting groove 130.

[0071] The first plate 110 also has a through hole 150, which is located at the bottom of the mounting groove 130 and communicates with the mounting groove 130. The lower end of the electrode post 200 can extend out of the mounting groove 130, which facilitates the connection of the electrode post 200 with the tab of the internal electrode assembly.

[0072] like Figure 4 and Figure 5 As shown, the first plate 110 includes a first region 110a and a second region 110b connected to each other. The first region 110a may protrude from the second region 110b, or it may be recessed into the second region 110b. The perforation 150 and the enclosure portion 120 are both located in the first region 110a. The first region 110a refers to a local area formed by deformation treatment on the surface of the plate. Specifically, a stamping process can be used to form a protruding or recessed structure on the surface of the plate. The first region 110a is used to centrally arrange the pole posts 200 to install related functional components. The structure of protruding from or recessed into the second region 110b refers to the change in surface morphology of the first region 110a relative to other regions of the plate. Specifically, it can be achieved by forming a stepped, arc-shaped, or folded structure through mold forming or machining.

[0073] In this embodiment, the protrusion of the first region 110a can increase the distance between the top surface of the pole post 200 and the surface of the second region 110b, while the depression of the first region 110a can decrease the distance between the top surface of the pole post 200 and the surface of the second region 110b. By designing the first region 110a with different degrees of protrusion and depression, the effect of increasing or decreasing the degree of protrusion of the pole post 200 can be achieved, thereby enabling the use of pole posts 200 and sealing rings 400 of the same specification to accommodate top cover assemblies with different pole post 200 height requirements.

[0074] In some embodiments, the top cover assembly further includes a sealing ring 400 disposed between the pole post 200 and the bottom wall of the mounting groove 130, and surrounding the edge of the perforation 150; the upper plastic 300 abuts against the sealing ring 400 to form a continuous sealing path between the pole post 200 and the top cover sheet 100.

[0075] It should be noted that the pole post 200 and the top cover plate 100 provide axial compressive force to the sealing ring 400, causing the sealing ring 400 to compress and deform. By designing the second section 122 as a ring structure with uniform wall thickness and designing the first limiting part 140 only in the first section 121, a compressive force is formed that is uniformly distributed along the axial direction, which can improve the uniformity of the compression of the sealing ring 400, thereby further improving the sealing reliability.

[0076] The upper plastic 300 is an insulating or conductive structure filled between the pole post 200 and the inner wall of the mounting groove 130. The formation method and specific structure of the upper plastic 300 are described in detail below.

[0077] In addition to the integral rubber coating mentioned above during the riveting process of the top cover plate 100, this application also proposes the following three structural methods:

[0078] like Figure 1 and Figure 2 As shown, in the first construction method, the upper plastic 300 covers the outside of the pole post 200, and the edge of the second section 122 presses against the upper plastic 300. The second section 122 is kept vertical before processing. The upper plastic 300 is pre-covered on the outside of the pole post 200 to form an integral structure. The pole post 200 and the upper plastic 300 are placed in the mounting groove 130. The second section 122 is bent into a horizontal state by riveting. The radial pressure and axial pressure generated by bending directly act on the outer surface of the upper plastic 300, thereby realizing the fixation between the pole post 200, the upper plastic 300 and the top cover plate 100.

[0079] In this construction method, the upper plastic 300 and the pole post 200 are pre-assembled as an integral structure. During the riveting process, it is not necessary to perform the plastic wrapping operation at the same time. This can avoid the extrusion force of the plastic wrapping acting on the outer ring 230 of the pole post 200, which would cause deformation of the outer ring 230 of the pole post 200. This helps to ensure the shape of the outer ring 230 and further improves the consistency of the compression of the sealing ring 400 to ensure the sealing performance.

[0080] like Figure 6As shown, in the second construction method, the upper plastic 300 is wrapped around the inner wall of the first section 121 and the second section 122. The inner wall refers to the side wall of the first section 121 and the second section 122 facing the mounting groove 130. The upper plastic 300 wrapped around the second section 122 presses against the pole post 200. The second section 122 is kept vertical before processing. The upper plastic 300 is pre-wrapped around the inner side wall of the first section 121 and the second section 122 or wrapped around the inner and outer side walls of the first section 121 and the second section 122 to form an integral structure. The pole post 200 is placed in the mounting groove 130. The second section 122 is bent into a horizontal state by riveting. The bending of the second section 122 forces the upper plastic 300 to deform and press against the pole post 200. At the same time, the deformation can compensate for processing errors.

[0081] In this construction method, the upper plastic 300 and the top cover 100 are pre-assembled as an integrated structure, avoiding the need for plastic wrapping during riveting, thus achieving a similar technical effect to the first construction method.

[0082] The third construction method involves machining the second segment 122 into a horizontal state, then installing the electrode post 200 into the mounting groove 130, and injecting adhesive between the electrode post 200 and the inner wall of the mounting groove 130 to form an upper plastic 300. It should be noted that the inner diameter of the second segment 122 must be larger than the outer diameter of the electrode post 200 to facilitate installation of the electrode post 200 into the mounting groove 130. The annular space formed between the first segment 121, the second segment 122, and the electrode post 200 allows for the injection of liquid plastic, which, after curing, forms the upper plastic 300. The upper plastic 300 forms an interference fit with the outer wall of the electrode post 200 and the inner wall of the mounting groove 130.

[0083] In this construction method, the enclosing portion 120 of the top cover 100 is pre-processed to form a folded edge structure, avoiding the need for adhesive wrapping during riveting, thus achieving a similar technical effect to the first construction method.

[0084] The upper plastic 300 can be made entirely of high-temperature resistant insulating material or high-temperature resistant conductive material. When the upper plastic 300 is made of a single high-temperature resistant material, the high-temperature stability of the material can prevent the sealing ring 400 from being under-compressed due to plastic softening, thereby maintaining the continuity of the sealing path.

[0085] Or, such as Figure 7As shown, the upper plastic 300 includes an overmolded portion 341 and an injection portion 342. The overmolded portion 341 refers to a plastic layer that is pre-attached to the outside of the electrode post 200 through injection molding or overmolding. The overmolded portion 341 is made of high-temperature resistant insulating material or high-temperature resistant conductive material. Glue is injected between the overmolded portion 341 and the inner wall of the mounting groove 130 to form the injection portion 342. When the upper plastic 300 adopts a combined structure of the overmolded portion 341 and the injection portion 342, the overmolded portion 341 directly isolates the heat conduction path between the electrode post 200 and the top cover plate 100 through the high-temperature resistant material. The injection portion 342 is injected into the gap between the inner wall of the mounting groove 130 and the overmolded portion 341 after overmolding. The local gaps caused by the processing tolerances of the electrode post 200 and the top cover plate 100 are eliminated through two molding processes. The tight wrapping of the rubber-coated part 341 and the pole post 200 can avoid interface separation caused by material shrinkage at high temperature, and the fluidity of the glue injection part 342 can compensate for the machining tolerance of the inner wall of the mounting groove 130 of the top cover plate 100.

[0086] High-temperature resistant insulating materials refer to materials that can maintain their insulating properties and do not soften under high-temperature environments. They can be used to connect with the negative electrode post 200. High-temperature resistant insulating materials can be ceramic-based organosilicon, resin materials with ceramic particles dispersed inside, LCP materials (Liquid Crystal Polymer), etc. High-temperature resistant conductive materials refer to materials that have stable conductivity and do not decrease mechanical strength at high temperatures. They can be used to connect with the positive electrode post 200. High-temperature resistant conductive materials can be PPS (polyphenylene sulfide) or polyimide with conductive fillers. This application does not limit the specific materials used.

[0087] The upper plastic 300 is made of high-temperature resistant insulating or high-temperature resistant conductive material, which ensures that the sealing interface maintains consistent deformation during thermal cycling, preventing the upper plastic 300 from melting and overflowing, thereby maintaining the stability of the compression deformation of the sealing ring 400. Furthermore, thanks to the material properties of the high-temperature resistant insulating or high-temperature resistant conductive material, the thickness of the upper plastic 300 can be reduced while maintaining its insulation or conductivity properties. This reduces the gap between the electrode post 200 and the inner wall of the mounting groove 130, increasing the usable internal space of the battery.

[0088] like Figure 12 and Figure 13As shown, the upper plastic 300 also has a portion located outside the enclosure 120. In this case, the top cover 100 also has a third limiting groove 160, which is located outside the first segment 121. The structure of the upper plastic 300 located outside the enclosure 120 can be fixedly connected to the third limiting groove 160. This increases the connection area between the upper plastic 300 and the top cover 100, enhances the connection stability of the upper plastic 300, and limits the axial runout of the upper plastic 300 and the pole post 200. Furthermore, for the upper plastic 300 with insulation requirements, the upper plastic 300 covering the outside of the enclosure 120 can increase the distance between the pole post 200 and the exposed area of ​​the top cover 100, improving insulation reliability.

[0089] like Figure 3 The upper plastic 300 shown has a first end 301 and a second end 302, and the upper plastic 300 can have different degrees of coverage on the pole post 200.

[0090] like Figure 1 and Figure 3 As shown, the first end 301 of the upper plastic 300 is located outside the mounting groove 130, as... Figure 16 and Figure 17 As shown, the first end 301 of the upper plastic 300 can protrude from the second section 122, thereby reducing the risk of creepage.

[0091] like Figure 4 and Figure 5 As shown, when the first region 110a of the mounting post 200 is recessed, a third limiting groove 160 is formed at the transition between the first region 110a and the second region 110b, and the structure of the upper plastic 300 located outside the enclosure 120 can be fixedly connected to the third limiting groove 160.

[0092] like Figure 7 As shown, the second end 302 of the upper plastic 300 can be located between the side wall of the pole post 200 and the first section 121, and there is a gap between the second end 302 of the upper plastic 300 and the bottom wall of the mounting groove 130. In this case, the upper plastic 300 only covers the side wall of the pole post 200. Correspondingly, the cross section of the sealing ring 400 needs to be designed as an L-shape or the outer edge of the sealing ring 400 abuts against the side wall of the mounting groove 130, so that when the sealing ring 400 is compressed, it can be squeezed and deformed between the pole post 200 and the side wall of the mounting groove 130 until it abuts against the second end 302 of the upper plastic 300 to form a continuous sealing path.

[0093] like Figure 14 and Figure 15As shown, the second end 302 of the upper plastic 300 can also be connected to the bottom wall of the mounting groove 130, and the second end 302 of the upper plastic 300 extends between the pole post 200 and the bottom wall of the mounting groove 130. In this case, the upper plastic 300 includes part of the bottom structure of the pole post 200, so that the first anti-torsion structure can have a larger vertical extension length and avoid stress concentration. In addition, for the case where the upper plastic 300 and the pole post 200 are pre-installed as an integral structure, the upper plastic 300 can form a U-shaped wrap around the side of the pole post 200 to reduce the risk of the upper plastic 300 falling off.

[0094] Furthermore, such as Figures 1 to 3 As shown, based on the case where the upper plastic 300 and the pole post 200 or the enclosure portion 120 are pre-assembled as an integral structure, the second end 302 of the upper plastic 300 may have a first limiting groove 330. The sealing ring 400 includes an annular body 220 and a sealing protrusion. The annular body 220 is disposed between the pole post 200 and the bottom wall of the mounting groove 130. The sealing protrusion is connected to the outer wall of the annular body 220 and extends into the first limiting groove 330. In this embodiment, the sealing protrusion of the sealing ring 400 is formed by the compression deformation of the sealing ring 400. When the pole post 200 is subjected to external force, the compression amount of the sealing ring 400 changes, but the sealing protrusion still needs to remain in the first limiting groove 330 to avoid the gap between the sealing ring 400 and the upper plastic 300 that would connect the pole post 200 and the inner wall of the mounting groove 130, thus maintaining a continuous sealing path.

[0095] Taking the extension of the second end 302 of the plastic 300 to the bottom wall between the pole post 200 and the mounting groove 130 as an example, the second end 302 of the plastic 300 forms a continuously bent stepped surface, specifically including a first vertical stepped surface, a horizontal stepped surface and a second vertical stepped surface. The first vertical stepped surface, the horizontal stepped surface and the bottom wall of the mounting groove 130 form a first limiting groove 330. The sealing ring 400 is compressed and deformed to press against each stepped surface. When the pole post 200 is subjected to external force and the compression of the sealing ring 400 changes, the sealing ring 400 still presses against the second stepped surface, and part of the structure is located in the first limiting groove 330. That is to say, the existence of the first limiting groove 330 allows for a certain degree of variation in the compression of the sealing ring 400.

[0096] There is a gap between the second end 302 of the upper plastic 300 and the bottom wall of the mounting groove 130. The stepped surface and the side wall of the mounting groove 130 form a first limiting groove 330. This application will not describe this in detail. The stepped surface can be set to more, or the first limiting groove 330 can be directly formed by processing the second end 302 of the upper plastic 300. This application does not limit this.

[0097] In practical applications, the first limiting part 140 can be provided on different surfaces or have different shapes, and the position and shape of the third limiting part 310 are adapted to the position and shape of the first limiting part 140; the second limiting part 210 can be provided on different surfaces or have different shapes, and the position and shape of the fourth limiting part 320 are adapted to the position and shape of the second limiting part 210. The first limiting part 140 and the second limiting part 210 will be described in detail below.

[0098] For ease of description, the mating structure between the first limiting part 140 and the third limiting part 310 is defined as the first anti-torsion structure, and the mating structure between the second limiting part 210 and the fourth limiting part 320 is defined as the second anti-torsion structure. Of the first limiting part 140 and the third limiting part 310, one is a protruding structure and the other is a grooved structure; of the second limiting part 210 and the fourth limiting part 320, one is a protruding structure and the other is a grooved structure.

[0099] The first limiting part 140 is provided on the side wall of the mounting groove 130, specifically, as follows: Figures 8 to 10 As shown, the first limiting part 140 can be a first limiting protrusion formed on the side wall of the mounting groove 130, and the first limiting protrusion is connected to the bottom wall of the mounting groove 130. That is, the first limiting protrusion connects the first section 121 of the enclosure part 120 and the plate body. While cooperating with the third limiting part 310, the first limiting protrusion can also act as a reinforcing rib to enhance the overall structural rigidity of the top cover plate 100 and prevent the side wall from deforming under stress during riveting.

[0100] like Figure 11 As shown, the first limiting part 140 can be a limiting rib extending in the vertical direction, the first limiting part 140 can also be a block structure that is narrow at the top and wide at the bottom, or the first limiting part 140 can be a triangular block structure that connects the bottom wall and the side wall of the mounting groove 130. This application does not limit this.

[0101] like Figure 4 and Figure 5As shown, when the first limiting portion 140 is progressively arranged along the direction near the bottom wall, that is, when the first limiting portion 140 is a block structure that is narrower at the top and wider at the bottom, for example, the cross-section of the first limiting portion 140 perpendicular to the radial direction can be triangular, trapezoidal, semi-circular, etc., guide surfaces are formed on opposite sides of the first limiting portion 140, and the distance between the guide surfaces on both sides increases progressively along the direction near the bottom wall of the mounting groove 130. Correspondingly, the third limiting portion 310 also has two oppositely arranged guide surfaces, and the guide surfaces of the third limiting portion 310 and the guide surfaces of the first limiting portion 140 cooperate with each other to achieve limiting. In the case of injection molding to form the upper plastic 300, the guide surfaces can play a guiding role during injection, reducing the risk of air gaps forming inside the upper plastic 300. In the case where the upper plastic 300 is pre-covered on the outside of the pole post 200, the guide surface can play a guiding role when installing the assembly of the pole post 200 and the upper plastic 300, and automatically align the third limiting part 310 on the upper plastic 300 with the first limiting protrusion, reducing the assembly difficulty.

[0102] The second limiting part 210 can be located on different surfaces depending on the specific shape of the pole post 200. Specifically, the pole post 200 includes a main body 220 and an outer ring part 230 disposed on the outside of the main body 220. The above structure is a common shape of the pole post 200, and will not be described in detail in this application. The second limiting part 210 can be a protruding structure or a groove structure. The main body 220, the outer ring part 230 and the second limiting part 210 are connected as an integral structure, and this application does not limit this.

[0103] In the first example of the above embodiments, as Figures 1 to 3 As shown, the surface where the first limiting part 140 is located intersects the surface where the second limiting part 210 is located. Specifically, the second limiting part 210 can be provided on the top surface of the outer ring part 230. The limiting directions of the first anti-torsion structure and the second anti-torsion structure form a spatial intersection, so that the pole post 200 is subjected to constraint forces from different planes when it rotates circumferentially, thereby dispersing the stress concentration area.

[0104] When the second limiting part 210 is configured as a limiting groove 212 on the top surface of the outer ring part 230, the depth of the limiting groove 212 is less than the thickness of the outer ring part 230. This avoids forming a completely through structure on the outer ring part 230, thereby maintaining the structural strength of the outer ring part 230 and the integrity of the bottom surface of the outer ring part 230, and preventing deformation of the outer ring part 230 caused by the injection extrusion pressure and the reaction force of the compression sealing ring 400 during the injection of the upper plastic 300.

[0105] The second limiting part 210 can be a dot-shaped protrusion or a dot-shaped groove provided on the top surface of the outer ring part 230. The cross-sectional shape can be a regular or irregular shape such as a circle or a square. This application does not limit this.

[0106] The second limiting part 210 can also be a limiting rib extending radially. One end of the limiting rib is connected to the outer wall of the pole post 200, and the other end of the limiting rib extends to be flush with the outer wall of the outer ring part 230, thereby maximizing the limiting path of the second limiting part 210 and facilitating the dispersion of torque.

[0107] In the second example of the above embodiments, such as Figures 9 to 11 As shown, the surface of the first limiting part 140 is parallel to the surface of the second limiting part 210. Specifically, the second limiting part 210 may be provided on the outer wall of the column or on the outer wall of the outer ring part 230.

[0108] However, when the second limiting part 210 is provided on the outer side wall of the outer ring part 230, the second limiting part 210 and the first limiting part 140 are misaligned circumferentially. That is, the second anti-torsion structure and the first anti-torsion structure are spaced apart along the outer periphery of the pole post 200 to avoid alignment along the same radial direction and to prevent the formation of a narrow area with a sudden change in size between the side walls of the side wall mounting groove 130 of the pole post 200 at the location of the first limiting part 140.

[0109] In practical applications, the second limiting part 210 can be designed as follows: Figure 10 The wave-like structure shown on the outer wall of the second limiting part 210 is not limited in this application.

[0110] It should be noted that there are multiple first limiting parts 140 and multiple second limiting parts 210. Multiple first limiting parts 140 are arranged at intervals along the circumference of the mounting groove 130, and multiple second limiting parts 210 are arranged at intervals along the circumference of the pole post 200, which is beneficial for torque distribution. This application will not provide a detailed description of this.

[0111] Furthermore, such as Figure 12 and Figure 13 As shown, in order to limit the sealing ring 400, a fifth limiting part 550 can be provided on at least one of the bottom walls of the pole post 200 and the mounting groove 130. The fifth limiting part 550 can be a pressing protrusion or a second limiting groove.

[0112] Specifically, the following forms are included: a pressing protrusion or a second limiting groove is provided only on the pole post 200; a pressing protrusion or a second limiting groove is provided only on the bottom wall of the mounting groove 130; both the bottom walls of the pole post 200 and the mounting groove 130 are provided with pressing protrusions; both the bottom walls of the mounting groove 130 of the pole post 200 are provided with second limiting grooves; and one of the bottom walls of the pole post 200 and the mounting groove 130 is provided with a pressing protrusion, while the other is provided with a second limiting groove. This application does not limit this.

[0113] The clamping protrusion can axially press against the sealing ring 400, and the presence of the second limiting groove allows part of the sealing ring 400 to be embedded in the second limiting groove when the sealing ring 400 is compressed, preventing the sealing ring 400 from shifting during compression. Furthermore, the presence of the clamping protrusion or the second limiting groove enables misaligned sealing between the sealing ring 400 and the pole post 200, and between the sealing ring 400 and the bottom wall of the mounting groove 130, further improving sealing performance.

[0114] In some specific embodiments, the pressing protrusion can be an annular protrusion surrounding the through hole 150, and the height of the pressing protrusion can be set to 10% to 30% of the original thickness of the sealing ring 400, for example, 0.1 mm to 0.3 mm. The second limiting groove can be an annular groove surrounding the outer periphery of the through hole 150, and the width of the annular groove can be set to 50% to 80% of the width of the sealing ring 400, for example, 1 mm to 1.5 mm. This application does not limit this.

[0115] The pressing protrusions can also be made of continuously distributed protrusions or grooves in combination with ribs. The cross-section of the pressing protrusions can be an increasing structure that is narrower at the top and wider at the bottom, such as regular or irregular shapes like triangles, trapezoids, and semicircles. This application does not limit this.

[0116] In some embodiments, the top cover assembly further includes a lower plastic 500, which is connected to the top cover sheet 100 and separates the top cover sheet 100 from the internal electrode assembly. The lower plastic 500 has a mounting channel, which is coaxially arranged with the through hole 150. That is, the mounting channel and the through hole 150 together form the through path of the lower end of the electrode post 200, so that the lower end of the electrode post 200 protrudes from the lower plastic 500, facilitating the connection between the electrode post 200 and the electrode tab of the battery cell.

[0117] The lower plastic sheet 500 and the top cover sheet 100 can be connected by snap-fit.

[0118] In some examples, such as Figures 1 to 3 As shown, the lower plastic 500 includes a second plate 510 and a snap-fit ​​portion 530. The snap-fit ​​portion 530 forms an installation channel, passes through the through hole 150, and is snapped together with the edge of the through hole 150, avoiding localized material deformation caused by welding or riveting. Furthermore, the snap-fit ​​portion 530 is directly fixed using the through hole 150, eliminating the need for other designs on the top cover plate 100 and simplifying the connection structure between the top cover plate 100 and the lower plastic 500.

[0119] Specifically, the snap-fit ​​part 530 refers to an annular protrusion structure with elastic deformation capability. It can be integrally formed with the second plate 510 by injection molding process. The snap-fit ​​part 530 is designed as an annular structure with a diameter slightly larger than that of the through hole 150. When the snap-fit ​​part 530 is pressed into the through hole 150, its outer wall undergoes elastic contraction. After passing through the through hole 150, it elastically recovers and forms a mechanical interlock with the edge of the through hole 150. This process does not require high-temperature processing and avoids local material melting and deformation caused by traditional welding.

[0120] The snap-fit ​​portion 530 can also separate the inner wall surface of the pole post 200 and the perforation 150, and the snap-fit ​​portion 530 abuts against the sealing ring 400 to form a connection sealing path. Specifically, the sealing ring 400 may be squeezed radially under pressure to abut against the side wall of the snap-fit ​​portion 530, or the snap-fit ​​portion 530 may extend into the perforation 150 and then abut against the sealing ring 400 from its end. This application does not limit this to any particular method.

[0121] In other examples, such as Figure 18 and Figure 19 As shown, the first plate 110 has a hot melt hole 111, and the second plate 510 has a hot melt pillar. The hot melt pillar is fixedly connected to the hot melt hole 111 to fix the lower plastic 500 and the top cover plate 100. The hot melt pillar refers to a columnar protrusion connected to the second plate 510. Specifically, it can be integrally formed with the second plate 510 by injection molding process, and expands to fill the internal gap of the hot melt hole 111 after softening by heat.

[0122] Based on the above example, the hot-melt hole 111 includes a first-order hole 1111 and a second-order hole 1113. The hot-melt hole 111 refers to a through hole with a stepped structure, which can be formed on the first plate 110 by stamping or laser cutting. The stepped hole wall is used to guide the flow of hot-melt material and form a uniform filling layer. After the hot-melt column extends into the hot-melt hole 111, it is softened and expanded by heating. The molten material flows along the stepped hole wall and fills the gaps between the hole walls. The stepped structure guides the molten material to be evenly distributed. After cooling, a seamless fixed interface is formed, eliminating the thickness difference caused by uneven material flow in traditional riveting processes.

[0123] The first-order hole 1111 has a first wall surface 1112 opposite to the opening side of the hot-melt hole 111. The second-order hole 1113 is provided on the first wall surface 1112, and the depth from the first wall surface 1112 to the opening of the hot-melt hole 111 increases from the center to the edge. The second-order hole 1113 gradually expands in the direction away from the first-order hole 1111. The first-order hole 1111 refers to the stepped hole structure near the opening side of the hot-melt hole 111. Specifically, it can be implemented by a conical hole or a stepped hole. The depth of its first wall surface 1112 increases from the center to the edge, thereby expanding the contact area between the hot-melt column and the hole wall and guiding the material gradient distribution. The second-order hole 1113 refers to the extended hole structure located at the bottom of the first-order hole 1111. Specifically, it can be implemented by a gradually expanding conical hole or a curved hole. The depth of its second wall surface 1114 increases from the center to the edge, thereby expanding the contact area between the hot-melt column and the hole wall and guiding the material gradient distribution, thereby improving the hot-melt column hot-melt yield.

[0124] The increasing depth of the first wall surface 1112 of the first-order hole 1111 allows the hot-melt column material to preferentially flow towards the center during filling, forming a filling layer that is thin in the center and thick at the edges, thus avoiding stress concentration caused by material accumulation at the edges. The gradually expanding structure of the second-order hole 1113 provides lateral expansion space for the hot-melt column, and after the hot-melt column is filled, it forms an anti-detachment structure, improving the connection stability between the lower plastic 500 and the top cover plate 100.

[0125] The second-order hole 1113 has a second wall surface 1114 opposite to the opening side of the hot-melt hole 111. The second wall surface 1114 is at least partially structured such that the depth of the opening of the hot-melt hole 111 increases from the center to the edge. The first plate 110 also includes a connecting portion 112 and an anti-detachment portion 113. The connecting portion 112 connects the second wall surface 1114 and the anti-detachment portion 113. The anti-detachment portion 113 protrudes from the sidewall of the connecting portion 112, and there is a gap between the edge of the anti-detachment portion 113 and the opening edge of the hot-melt hole 111. After the hot-melt column fills the hot-melt hole 111, a first anti-detachment structure is formed between the hot-melt column and the sidewall of the second groove, and a second anti-detachment structure is formed between the hot-melt column and the anti-detachment portion 113, thereby further improving the connection stability between the lower plastic 500 and the top cover plate 100.

[0126] The anti-detachment part 113 can be located below the plane where the opening of the hot melt hole 111 is located. The minimum diameter of the hot melt column is located at the connection between the first-stage hole 1111 and the second-stage hole 1113. The connection interface between the top cover plate 100 and the lower plastic 500 is the plane where the opening of the hot melt hole 111 is located. By misaligning the minimum diameter of the hot melt column with the connection interface between the top cover plate 100 and the lower plastic 500, the shear force parallel to the connection interface when the top cover plate 100 or the lower plastic 500 is subjected to force is prevented from directly acting on the weak part of the hot melt column. Instead, the connection area between the hot melt column and the body structure of the lower plastic 500 is increased through the first-stage hole 1111, thereby improving the connection strength of the hot melt column and further improving the connection reliability between the lower plastic 500 and the top cover plate 100.

[0127] This application further proposes a battery, which includes the top cover assembly as described above. Thanks to the improvements made to the top cover assembly in the above embodiments, the battery of this utility model embodiment has the same technical effects as the top cover assembly in the above embodiments, which will not be repeated here.

[0128] The embodiments of this utility model have been described in detail above with reference to the accompanying drawings. However, this utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this utility model. Furthermore, unless otherwise specified, the embodiments of this utility model and the features thereof can be combined with each other.

Claims

1. A cap assembly, characterized by, include: The top cover plate includes a first plate and an enclosing portion, the enclosing portion being connected to the first plate to enclose and form a mounting groove, the mounting groove being provided with a first limiting portion; the enclosing portion includes a first section and a second section, the first section being connected to the first plate and the second section, the second section being an annular structure with a uniform wall thickness; The pole post, at least a portion of which is disposed within the mounting groove, is provided with a second limiting portion; The upper plastic, at least partially disposed between the pole post and the first segment, has a third limiting part and a fourth limiting part. The third limiting part cooperates with the first limiting part to limit the relative rotation of the upper plastic and the pole post, and the fourth limiting part cooperates with the second limiting part to limit the relative rotation of the upper plastic and the top cover plate.

2. The roof assembly of claim 1, wherein, The first limiting part connects the first segment and the first plate; and / or, The first limiting part is gradually widened along the direction close to the bottom wall of the mounting groove.

3. The roof assembly of claim 1, wherein, The pole post includes a main body and an outer ring portion disposed on the outer side of the main body; The second limiting part is provided on the side wall of the main body or the side wall of the outer ring part; Alternatively, the second limiting portion may be located on the top surface of the outer ring portion.

4. The roof assembly of claim 3, wherein, The second limiting part is provided on the side wall of the outer ring part, and the first limiting part and the second limiting part are offset along the outer periphery of the pole post.

5. The roof assembly of claim 3, wherein, The second limiting portion includes a second limiting protrusion disposed on the top surface or side wall of the outer ring portion; Alternatively, the second limiting portion includes a limiting groove provided on the top surface of the outer ring portion, the depth of the limiting groove being less than the thickness of the outer ring portion.

6. The roof assembly of claim 1, wherein, The upper plastic has a first end and a second end, with the second end being closer to the first plate body than the first end; Wherein, the second end is located between the pole post and the first section, and there is a gap between the second end and the bottom wall of the mounting groove; Alternatively, the second end is connected to the bottom wall, and the second end of the upper plastic extends between the pole and the bottom wall of the mounting groove.

7. The roof assembly of claim 6, wherein, The second end of the upper plastic has a first limiting groove, and the top cover assembly also includes a sealing ring. The sealing ring includes an annular body and a sealing protrusion. The annular body is disposed between the pole post and the bottom wall of the mounting groove. The sealing protrusion is connected to the annular body and extends into the first limiting groove.

8. The roof assembly of claim 1, wherein, In the first limiting part and the third limiting part, one is a protruding structure and the other is a groove structure. The groove structure has two guide surfaces arranged opposite to each other. The distance between the two guide surfaces increases gradually along the direction close to the bottom wall of the mounting groove. The protruding structure is located between the two guide surfaces.

9. The roof assembly of any one of claims 1 to 8, wherein, The first plate includes a first area and a second area connected to each other, the first area protruding from or recessed into the second area, and the enclosing portion is provided in the first area.

10. The roof assembly of any one of claims 1 to 8, wherein, The top cover assembly also includes a lower plastic layer, which has hot melt pillars, and the first plate has hot melt holes, which include first-order holes and second-order holes. Wherein, the first-order hole has a first wall surface opposite to the opening side of the hot-melt hole, the second-order hole is disposed on the first wall surface, and the depth from the first wall surface to the opening of the hot-melt hole increases gradually from the center to the edge, and the second-order hole gradually widens in a direction away from the first-order hole; and / or, The second-order hole has a second wall surface opposite to the opening side of the hot-melt hole. The second wall surface is at least partially structured such that the depth of the opening of the hot-melt hole increases from the center to the edge. The first plate also includes a connecting portion and an anti-detachment portion. The connecting portion connects the second wall surface and the anti-detachment portion. The anti-detachment portion protrudes from the side wall of the connecting portion and there is a gap between the edge of the anti-detachment portion and the opening edge of the hot-melt hole.

11. The roof assembly of any one of claims 1 to 8, wherein, The top cover assembly also includes a sealing ring, which is disposed between the pole post and the bottom wall of the mounting groove; At least one of the pole post and the bottom wall of the mounting groove is provided with a fifth limiting part, which is used to limit the radial movement of the sealing ring. The fifth limiting part is a pressing protrusion or a second limiting groove.

12. The roof assembly of any one of claims 1 to 8, wherein, The top cover has a third limiting groove, which is located on the outside of the enclosure, and the upper plastic part is fixedly connected to the third limiting groove.

13. The roof assembly of any one of claims 1 to 8, wherein, The upper plastic is configured as an integral structure made of high-temperature resistant insulating material or high-temperature resistant conductive material. Alternatively, the upper plastic part includes a coating part and a glue injection part. The coating part covers the outer side of the pole post. The coating part is an integral structure made of high-temperature resistant insulating material or high-temperature resistant conductive material. The glue injection part is located between the inner wall of the mounting groove and the coating part.

14. A battery, characterized by Includes the top cover assembly as described in any one of claims 1 to 13.

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