CN220753593U

CN220753593U - Secondary battery top cover assembly and battery

Info

Publication number: CN220753593U
Application number: CN202322453634.XU
Authority: CN
Inventors: 李亚勇
Original assignee: Shenzhen Everwin Precision Technology Co Ltd
Current assignee: Shenzhen Everwin Precision Technology Co Ltd
Priority date: 2023-09-08
Filing date: 2023-09-08
Publication date: 2024-04-09
Anticipated expiration: 2033-09-08

Abstract

The utility model discloses a secondary battery top cover assembly and a battery, wherein the secondary battery top cover assembly comprises a top cover plate, a pole, a sealing ring, an upper plastic part, a lower plastic part, an explosion-proof piece and a protection piece; the top cover plate is provided with a liquid injection port and a pole mounting hole for the pole to penetrate through the top cover plate; the top cover sheet is also provided with an explosion-proof sheet mounting hole for placing the explosion-proof sheet; the post includes protruding portion, recess, base and sealing washer fixed part, and the sealing washer snare is established on the sealing washer fixed part, and wherein, the external diameter of sealing washer fixed part is greater than the internal diameter of sealing washer. Compared with the existing top cover assembly, the outer diameter of the sealing ring fixing part on the pole is larger than the inner diameter of the sealing ring, so that the sealing ring is in interference fit with the pole, and the sealing ring is fixed in place during injection molding, is not easy to loosen and has good sealing performance.

Description

Secondary battery top cover assembly and battery

Technical Field

The utility model relates to the technical field of batteries, in particular to a top cover assembly of a secondary battery and the battery.

Background

Along with the rapid development of technology in the new energy field, the energy density requirement of the battery is increased, and at present, the top cover assembly of the secondary battery mostly adopts an injection molding mode to complete the fixation between the pole and the top cover sheet. In the injection molding process, the pole, the top cover plate, the sealing ring and other components are required to be assembled firstly and then are put into an injection mold for integral molding. The inner diameter of the sealing ring is generally larger than the outer diameter of the upper end of the pole, so that the sealing ring is easy to loosen and fall off after being sleeved on the pole, and is not easy to position; the sealing ring is installed by considering the factors such as size matching, compression ratio, restorability, contact performance with the pole/cover plate and the like. The improvement of the sealing ring is also an important technical direction for improving the performance and the safety of the lithium battery.

Disclosure of Invention

Aiming at the defects in the prior art, the utility model aims to solve the technical problems that: the secondary battery top cover assembly and the secondary battery are provided, and the problem that a sealing ring of the secondary battery top cover assembly is easy to loosen and difficult to position in an injection molding process is effectively solved.

In order to solve the technical problems, the utility model adopts a technical scheme that:

in one aspect, a secondary battery top cover assembly is provided, which comprises a top cover plate, a pole, a sealing ring, an upper plastic part and a lower plastic part; the pole comprises a protruding part, a groove, a sealing ring fixing part and a base; the inner diameter of the sealing ring is smaller than the outer diameter of the sealing ring fixing part, the sealing ring is in interference fit with the sealing ring fixing part, and the sealing ring is tightly attached to the sealing ring fixing part when compressed on the pole, so that the sealing ring is fixed on the pole.

Further, the top cover plate is provided with a liquid injection port and a pole mounting hole penetrating through the whole top cover plate, and the pole is mounted in the pole mounting hole.

Further, the upper surface of the top cover plate is provided with a fastening part, and the fastening part is arranged along the periphery of the pole mounting hole; the position department that goes up the plastic part corresponds the fastening portion forms the cooperation portion of mutually supporting, and fastening portion and cooperation portion cooperation have increased the area of contact between top cap piece and the last plastic part, realize the location and the fixed between top cap piece and the last plastic part.

Further, the fastening portion is defined as an annular convex ring, the mating portion is defined as an annular groove and/or the fastening portion is an annular groove, and the mating portion is an annular convex ring.

Further, the position of the mounting hole of the lower plastic part pole is provided with an annular protruding limiting part, and the protruding limiting part is used for limiting the sealing ring when compressed after riveting the pole.

Further, the pole comprises a first pole and a second pole, wherein the lower plastic part comprises a first lower plastic part positioned below the first pole and a second lower plastic part positioned below the second pole.

Further, the protruding portion is located above the groove, wherein the protruding portion protrudes out of the upper plastic piece.

Further, the recess is connected to sealing washer fixed part one end, and the base is connected to the other end, and the external diameter of recess is less than the external diameter of sealing washer fixed part, wherein, through the extension portion that the external diameter that extends from the recess to sealing washer fixed part gradually becomes big between recess and the sealing washer fixed part.

Further, the section of one end of the sealing ring fixing part connecting groove is smaller than the section of the other end of the sealing ring fixing part connecting base.

In another aspect, the present utility model also provides a power battery, including any one of the above secondary battery top cap assemblies.

The secondary battery top cover assembly of the utility model has the following beneficial effects:

the outer diameter of the sealing ring fixing part of the pole is set to be larger than the inner diameter of the sealing ring sleeved outside the pole, so that the sealing ring and the sealing ring fixing part are in interference fit before the top cover sheet and the pole are formed into a top cover sheet assembly through injection molding, and the sealing ring can be tightly sleeved on the pole; the extending part with the gradually enlarged outer diameter arranged between the groove and the sealing ring fixing part can facilitate the sealing ring to be sleeved at the position of the sealing ring fixing part slowly; meanwhile, the device can be convenient to provide a good positioning effect in the injection molding process, so that the sealing performance of the whole structure of the top cover assembly of the secondary battery is good.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application and do not constitute an undue limitation to the application. In the drawings:

fig. 1 is an exploded view of a top cap assembly of a secondary battery according to the present utility model;

fig. 2 is a schematic view showing a structure of a top cap assembly for a secondary battery according to the present utility model;

FIG. 3 is a cross-sectional view of A-A of FIG. 2;

FIG. 4 is an enlarged view of a portion of the view shown in FIG. 3;

FIG. 5 is a perspective view of the structure of a pole piece in the power cell top cap assembly provided by the present utility model;

fig. 6 is a schematic view of a structure before riveting a post in a top cap assembly of a secondary battery according to the present utility model;

fig. 7 is a schematic structural diagram of the post riveting provided by the utility model;

fig. 8 is a schematic perspective view of an upper plastic part according to the present utility model.

The meaning of the reference numerals in the drawings are:

1. a secondary battery top cap assembly; 10. a top cover sheet; 101. a liquid injection port; 102. a post mounting hole; 103. explosion-proof piece mounting holes; 104. a fastening part; 20. a pole; 201. a protruding portion; 202. a groove; 203. an extension; 204. a seal ring fixing part; 205. a base; 21. a first pole; 22. a second post; 30. a seal ring; 40. explosion-proof sheet; 50. a burst disk protective sheet; 60. a plastic part is arranged; 601. a mating portion; 70. a lower plastic part; 701. a first lower plastic part; 702. a second lower plastic part; 703. protruding limit part.

Detailed Description

For the purposes, technical solutions and advantages of the present application, the technical solutions of the present application will be clearly and completely described below with reference to specific embodiments of the present application and corresponding drawings. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

It will be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model.

Referring to fig. 1, 2 and 3, the top cap assembly for a secondary battery provided by the present utility model includes a top cap plate 10, a pole 20, an upper plastic member 60 and a lower plastic member 70; the pole 20 includes a first pole 21 and a second pole 22.

In practical application, the first pole 21 is a positive pole, the second pole 22 is a negative pole, and the negative pole is a composite pole, which may be a copper-aluminum composite pole or a copper alloy pole or an aluminum alloy pole.

The top cover sheet 10 is provided with a liquid injection port 101 for injecting electrolyte into the cell; the top cover sheet 10 is further provided with a post mounting hole 102 in which the positive and negative electrode posts 21 and 22 are mounted to penetrate the entire top cover sheet 10. The top sheet 10 is further provided with a rupture disc mounting hole 103 for receiving the rupture disc 40 and the rupture disc protection sheet 50.

Referring to fig. 1 and 3, the top cover sheet 10 has an upper surface and a lower surface, and the upper plastic member 60 is injection molded on the top surface of the top cover sheet 10 at a position opposite to the mounting hole 102; the rupture disc protection sheet 50 is mounted on the rupture disc mounting hole 103 of the upper surface of the cover sheet 10, and the rupture disc 40 is mounted on the rupture disc mounting hole 103 of the lower surface. A sealing ring 30 is arranged between the lower surface, opposite to the pole mounting hole 102, of the top cover plate 10 and the pole 20, the sealing ring 30 is sleeved on the pole 20, and the sealing ring 30 can prevent electrolyte in the battery core from leaking from the pole 20 to cause short circuit of the battery.

Referring to fig. 1, 3, 4 and 8, the top cover 10 has a fastening portion 104 formed around the pole mounting hole, and correspondingly, when the upper plastic member 60 is injection molded, a fitting portion 601 for fitting the fastening portion 104 of the top cover 10 is formed on the upper plastic member 60, and after the upper plastic member 60 is fitted, the fastening portion 104 increases the contact area between the upper plastic member 60 and the top cover 10, thereby improving the sealing reliability and playing a role of positioning and rotation prevention. In the actual assembly of the top cover assembly, the upper plastic member 60 may be directly injection molded on the upper surface of the top cover plate 10, or may be separately molded and then assembled on the upper surface of the top cover plate 10.

In one embodiment, the fastening portion 104 may be an annular collar defined to be disposed about the circumference of the pole mounting bore 102; the annular convex ring is integrally protruded from the upper surface of the top cover sheet 10 toward the direction approaching the upper plastic member 60, and the corresponding engaging portion 601 is defined as an annular groove formed at the bottom of the upper plastic member and engaged with the annular convex ring.

In another embodiment, the fastening portion 104 may be an annular groove defined to be disposed around the circumference of the pole mounting hole 102; the annular groove is formed by recessing from the upper surface of the top cover sheet 10 toward a direction away from the upper plastic member 60, and the corresponding engaging portion 601 is defined as an annular convex ring protruding from the bottom of the upper plastic member and engaging with the annular groove.

The lower plastic part 70 is provided with an annular protruding limiting part 703 at the position of the pole mounting hole, when the pole 20 is riveted, the sealing ring 30 is extruded and radially expanded, and the protruding limiting part 703 can limit the sealing ring. In addition, the lower plastic part 70 includes a first lower plastic part 701 located directly under the first pole 21 and a second lower plastic part 702 located directly under the second pole 22.

Referring to fig. 4, 5 and 6, the pole 20 includes a protruding portion 201 at an upper end of the pole, and includes a groove 202, an extension portion 203, a seal ring fixing portion 204 and a base 205 sequentially from the protruding portion 201. The outer diameter of the groove 202 is smaller than the outer diameters of the protruding portion 201, the seal ring fixing portion 204 and the base 205, and the outer diameter of the extending portion 203 in the direction from the groove 202 to the seal ring fixing portion 204 becomes larger gradually, that is, the cross section of the end of the seal ring fixing portion 204 connected with the extending portion 203 is larger than the cross section of the end of the groove 202 connected with the extending portion 203.

When the sealing ring 30 is installed, the sealing ring 30 is sleeved at the groove 202 firstly, then slowly moves from the extension part 203 to the sealing ring fixing part 204 and finally is tightly sleeved on the groove, and the extension part 203 is arranged so that the outer diameter gradually becomes larger, so that the sealing ring 30 can conveniently move to the sealing ring fixing part 204; after the seal ring 30 moves onto the seal ring fixing portion 204 completely, since the inner diameter of the seal ring 30 is smaller than the outer diameter of the seal ring fixing portion 204, the seal ring 203 is in interference fit with the seal ring fixing portion 204; the sealing ring 30 at this time can have a good positioning effect when the top cover sheet 10 and the pole 20 are injection molded, and the sealing ring 30 is not easy to fall off.

Referring to fig. 6 and 7, fig. 6 is a schematic view showing a structure in which the upper end of the pole 20 is not riveted, and when the riveting is performed, the upper end of the pole 20 is gradually flattened outward, and the pole structure shown in fig. 7 is formed after the riveting is completed.

Referring to fig. 1, the upper plastic member 60, the top cover sheet 10, the seal ring 30, the pole 20 and the lower plastic member are sequentially arranged from top to bottom; the protruding part 201 protrudes partially over the upper plastic part 60. The lower plastic member 70 is further provided with a through hole portion through which the pole 20 passes.

The secondary battery top cap assembly 1 of the present utility model is assembled as follows: firstly, mounting a sealing ring 30 from the upper end of a non-riveted pole 20 to a sealing ring fixing part 204 of the pole 20, and mounting a explosion-proof sheet 40 in an explosion-proof sheet mounting hole 103; then the lower plastic part 70 and the top cover sheet 10 are installed together, then the non-riveted pole 20 with the sealing ring 30 is inserted into the through hole of the lower plastic part 70 and the pole installation hole 102 of the top cover sheet 10 from the lower side of the lower plastic part 70, and then the upper end of the pole 20 is riveted, so that the upper end of the pole 20 is flanged outwards along the radial direction and flattened; finally, the upper plastic part 60 is positioned through the annular protrusion 104 on the top cover plate 10, and the upper plastic part 60 which is molded separately is injection molded on the upper surface of the top cover plate 10 or assembled on the top cover plate 10, and at this time, the flanging of the pole post 20 is just pressed on the upper surface of the upper plastic part 60. Under the riveting of the pole 20 and the forming of the upper plastic part 60, the sealing ring 30 is extruded to expand outwards along the radial direction, and at the moment, the protruding limiting part 703 of the lower plastic part 70 plays a role in limiting the sealing ring 30, and in addition, the protruding limiting part can be matched with the base in a positioning way, so that a rotation preventing effect is achieved. The secondary battery top cap assembly 1 has very reliable sealing performance under the action of the pole 20, the sealing ring 30, the upper plastic member 60 and the lower plastic member 70.

The embodiment also provides a battery, which comprises a battery shell and further comprises any secondary battery top cover assembly 1, and the battery has good overall sealing performance.

Compared with the prior art, the secondary battery top cover assembly 1 has the following beneficial effects: the outer diameter of the sealing ring fixing part 204 of the pole 20 is set to be larger than the inner diameter of the sealing ring 30 sleeved on the outer edge of the sealing ring fixing part, so that the sealing ring 30 and the sealing ring fixing part 204 are in interference fit before the top cover sheet 10 and the pole 20 are formed into the top cover sheet assembly 1 in an injection molding mode, and the sealing ring 30 can be tightly sleeved on the pole 20; the extending part 203 with the gradually enlarged outer diameter arranged between the groove 202 and the sealing ring fixing part 204 can facilitate the sealing ring 30 to be sleeved on the sealing ring fixing part 204 slowly; meanwhile, the device can be convenient to provide a good positioning effect in the injection molding process, so that the sealing performance of the whole structure of the top cover assembly of the secondary battery is good.

In the description herein, it should be understood that the terms "upper," "lower," "left," "right," and the like are based on the orientation or positional relationship shown in the drawings, and are merely for convenience of description and to simplify operation, rather than to indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the utility model.

The foregoing examples only represent preferred embodiments of the present utility model, which are described in more detail and are not to be construed as limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model. Accordingly, the scope of protection of the present utility model is to be determined by the appended claims.

Claims

1. A top cover assembly of a secondary battery comprises a top cover plate, a pole, a sealing ring, an upper plastic part and a lower plastic part; the method is characterized in that: the pole comprises a protruding part, a groove, a sealing ring fixing part and a base; the inner diameter of the sealing ring is smaller than the outer diameter of the sealing ring fixing part, the sealing ring is in interference fit with the sealing ring fixing part, and the sealing ring is tightly attached to the sealing ring fixing part when compressed on the pole so that the sealing ring is fixed on the pole.

2. The secondary battery top cap assembly according to claim 1, wherein: the top cover plate is provided with a liquid injection port and a pole mounting hole penetrating through the whole top cover plate, and the pole is mounted in the pole mounting hole.

3. The secondary battery top cap assembly according to claim 1, wherein: the upper surface of the top cover plate is provided with a fastening part, and the fastening part is arranged along the periphery of the pole mounting hole; the position department that goes up the plastic part corresponds the fastening portion forms the cooperation portion of mutually supporting, fastening portion with the cooperation of cooperation portion has increased the area of contact between top cap piece and the last plastic part, realizes the top cap piece with go up the location between the plastic part and fix.

4. The secondary battery top cap assembly according to claim 3, wherein: the fastening portion is defined as an annular convex ring, the mating portion is defined as an annular groove and/or the fastening portion is an annular groove, and the mating portion is an annular convex ring.

5. The secondary battery top cap assembly according to claim 1, wherein: the lower plastic part pole mounting hole position is provided with annular protruding limit part, protruding limit part is used for carrying out the spacing when the sealing washer is compressed after the pole riveting.

6. The secondary battery top cap assembly according to claim 1, wherein: the pole comprises a first pole and a second pole, wherein the lower plastic part comprises a first lower plastic part positioned below the first pole and a second lower plastic part positioned below the second pole.

7. The secondary battery top cap assembly according to claim 6, wherein: the protruding portion is located above the groove, and the protruding portion protrudes out of the upper plastic piece.

8. The secondary battery top cap assembly according to claim 7, wherein: the sealing ring fixing part is characterized in that one end of the sealing ring fixing part is connected with the groove, the other end of the sealing ring fixing part is connected with the base, the outer diameter of the groove is smaller than that of the sealing ring fixing part, and the groove and the sealing ring fixing part are connected through an extending part with gradually enlarged outer diameter extending from the groove to the sealing ring fixing part.

9. The secondary battery top cap assembly according to claim 8, wherein: the section of one end of the sealing ring fixing part connected with the groove is smaller than the section of the other end of the sealing ring fixing part connected with the base.

10. A secondary battery characterized in that: comprising the secondary battery top cap assembly according to any one of claims 1 to 9.