CN212659599U

CN212659599U - Secondary battery top cover

Info

Publication number: CN212659599U
Application number: CN202021571822.2U
Authority: CN
Inventors: 邓平华; 王雷; 黄大清
Original assignee: Jiangxi Bestley New Energy Technology Co ltd
Current assignee: Jiangxi Bestley New Energy Technology Co ltd
Priority date: 2020-07-31
Filing date: 2020-07-31
Publication date: 2021-03-05
Anticipated expiration: 2030-07-31

Abstract

The utility model provides a secondary battery top cap, include: the top cover plate, connect the first electrode unit and the second electrode unit of top cover plate, the top cover plate is equipped with first electrode and introduces the hole, first electrode unit is fixed in the first utmost point post of first electrode introduction hole including insulating and encloses the injection molding of locating first utmost point post and with first utmost point post and top cover plate insulation, first utmost point post forms the ring channel towards the outer wall of injection molding in the middle part indent, the injection molding joint in the ring channel, the tank bottom of ring channel is equipped with the chamfer with the department of meeting of upper portion cell wall. The annular groove is arranged, so that the connection between the injection molding piece and the top cover plate is firmer, and the connection strength between the injection molding piece and the top cover plate is higher. Meanwhile, a chamfer is arranged at the joint of the groove bottom of the annular groove and the upper groove wall, and a stress buffer area can be formed in the annular groove by the chamfer, so that the pressure impact of the molten plastic on the upper area of the pole column is relieved, the pole column positioned on the upper part of the annular groove is prevented from deforming, and the sealing performance and the safety of the top cover of the secondary battery are improved.

Description

Secondary battery top cover

Technical Field

The utility model relates to an energy storage apparatus field especially relates to a secondary battery top cap.

Background

In modern society, driving power sources for more and more electric tools and new energy vehicles are developed in a direction of high capacity and high safety, and batteries are widely used in electric tools and new energy vehicles due to their excellent characteristics such as high capacity. These batteries should have good safety in addition to high capacity to meet the standards of use and to meet the needs of people.

General secondary battery, the negative pole end needs to satisfy with the electrical insulation of top cap and casing, therefore can set up numerous insulating assemblies, if go up plastic part with negative pole post and top cap insulation, arrange the sealing washer that carries out electrical insulation and sealed in the negative pole mounting hole in, and carry out electrical insulation's lower plastic part with negative pole connection piece and top cap, these subassemblies are when carrying out the installation of top cap piece negative pole end, in order to control its gas tightness strictly, the required precision of its installation is very high, both carry out the pre-compaction to the sealing washer, clearance between each part of will strictly controlling again, therefore with high costs and yields are low.

In order to achieve the beauty of the secondary battery top cover and prevent additional electric connection between the pole and an external component, an injection molding part is usually arranged on the periphery of the pole, and although the problem can be solved through the injection molding part on the periphery of the pole (also called encapsulation, and injection is carried out after plastic materials are melted), the current encapsulation technology easily enables the pole to be subjected to pressure impact of molten plastic so as to deform. Therefore, there is a need to provide an effective encapsulation structure or encapsulation method to solve the problems of the current encapsulation technology.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a secondary battery top cap to prior art not enough, it not only can improve the firm nature of being connected between injection molding and the top cap, more importantly, its deformation that can effectual prevention utmost point post.

In order to achieve the above object, the utility model provides a secondary battery top cap, include: top cap piece, connection the first electrode unit and the second electrode unit of top cap piece, the top cap piece is equipped with first electrode and introduces the hole, first electrode unit is fixed in including insulating first electrode is introduced the first utmost point post in hole and is enclosed to be located first utmost point post will first utmost point post with the insulating injection molding of top cap piece, first utmost point post towards the outer wall of injection molding forms the ring channel in the middle part indent, the injection molding joint in the ring channel, the tank bottom of ring channel is equipped with the chamfer with the department of meeting of upper portion cell wall.

The utility model discloses a secondary cell top cap's first utmost point post forms the ring channel towards the outer wall of injection molding in the middle part indent, and injection molding joint in the ring channel, and setting up through the ring channel can make the connectivity of injection molding and top patch more firm, and both joint strength is higher. Meanwhile, because the setting of ring channel for utmost point post is big in the atress of ring channel department, and utmost point post is located the regional pressure impact that receives the melting plastic on ring channel upper portion easily and takes place to warp, causes the leakproofness variation between utmost point post and the injection molding, finally influences the leakproofness and the security of secondary cell top cap, based on this problem, the utility model discloses a tank bottom of ring channel is equipped with the chamfer with the department of meeting of upper portion cell wall, and the setting of chamfer can form a atress buffer zone in the ring channel to alleviate the regional pressure impact of melting plastic to utmost point post upper portion, takes place to warp in order to avoid being located ring channel upper portion, thereby improves the leakproofness and the security of secondary cell top cap.

Preferably, the chamfer is a straight chamfer, and the angle of the straight chamfer is 10-80 degrees, or the chamfer is an arc chamfer of R0.1-R1.0.

Preferably, the first electrode post comprises an extending part and a platform part which are connected in the vertical direction, the platform part is positioned at the lower part of the first electrode introducing hole, and the extending part penetrates through the first electrode introducing hole and the outer wall is recessed inwards to form the annular groove.

Preferably, a projection shape of a groove bottom of the annular groove in the vertical direction is the same as a projection shape of an outer contour of the protruding portion in the vertical direction. Because the connecting part of the groove bottom of the annular groove and the upper groove wall is provided with the chamfer, and the contour of the groove bottom of the annular groove is consistent with the contour shape of the pole on the annular groove, the strength of the upper part of the pole is favorably increased, and the phenomenon that the molten plastic impacts the upper part of the top cover to cause the deformation of the upper part of the pole is avoided.

Preferably, the first electrode unit further includes a sealing member interposed between the top cover plate and the first electrode post, an upper portion of the sealing member abuts against the top cover plate, and a side wall of the sealing member abuts against the first electrode post.

Preferably, the upper surface of the top cover plate is recessed around the first electrode lead-in hole to form a first groove, and the injection molding piece is embedded into the first groove. The connection firmness between the injection molding piece and the top cover plate can be improved through the arrangement of the first groove.

Preferably, the upper surface of the top cover plate is provided with a plurality of first notches for the injection molding part to be embedded and communicated with the first grooves, and the first notches are regularly arranged around the first grooves. The firm nature of connection between injection molding and the top cap piece not only can further be increased in the setting of first breach, can play the effect that prevents utmost point post rotation moreover. More preferably, a second notch for embedding the injection molding piece is arranged on the upper surface of the top cover piece around each first notch, and the depth of the second notch is smaller than that of the first notch. The connection firmness and the anti-rotation effect between the injection molding part and the top cover plate can be further enhanced through the arrangement of the second notch.

Preferably, the lower surface of the top cover plate is recessed around the first electrode introducing hole to form a second groove, and the second groove is communicated with the first electrode introducing hole.

Preferably, the lower part of the top cover plate is provided with a lower insulating part, the lower insulating part is provided with a clamping part, and the clamping part extends into the second groove and is clamped in the first pole column so as to improve the firmness and compactness of connection between the secondary battery top cover parts.

Drawings

Fig. 1 is a plan view of an embodiment of a secondary battery top cap according to the present invention.

Fig. 2 is a bottom view of an embodiment of a secondary battery top cap according to the present invention.

Fig. 3 is an exploded view of the secondary battery top cover of fig. 1 in a first direction.

Fig. 4 is an exploded view of the secondary battery top cover of fig. 1 in a second direction.

Fig. 5 is a sectional view taken in the direction a-a of fig. 1.

Fig. 6 is a sectional view taken in the direction B-B in fig. 1.

Fig. 7 is an enlarged view of the circled portion in fig. 5.

Fig. 8 is a perspective view of the first pole of fig. 1.

Fig. 9 is a perspective view of the first pole of fig. 2.

Fig. 10 is a partial perspective view of the top cover plate of the secondary battery top cover according to the present invention.

Description of the elements

100-secondary battery top cover; 1-top cover sheet; 11-a first electrode lead-in hole; 12-a second electrode introduction hole; 13-explosion-proof valve mounting hole; 14-a first groove; 15-a first notch; 16-a second notch; 17-a second groove; 2-second electrode unit/positive electrode unit; 21-positive pole column; 23-positive injection molding; 25-positive seal; 3-first electrode unit/negative electrode unit; 31-a negative electrode post; 311-an extension; 3111-ring channel; 3113-upper step portion; 313-a platform portion; 3131-a lower step; 3133-a notch; 33-injection molding; 35-a seal; 4-an explosion-proof valve assembly; 41-explosion-proof valve; 43-explosion-proof valve protection plate; 5-liquid injection hole; 6-lower insulation; 61-a clamping part; r-chamfer

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described more fully hereinafter with reference to the accompanying drawings. The preferred embodiments of the present invention are shown in the drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete. It should be noted that, in general, the secondary battery is placed vertically, one side of the secondary battery top cover, which extends out and is connected with the outside, is an upper side, i.e., a top direction, and the other side is a lower side, i.e., a bottom direction.

The secondary battery top cap and the secondary battery thereof according to the present invention will be described with reference to the accompanying drawings.

Referring to fig. 1 to 6, the secondary battery includes a battery cell, a case for accommodating the battery cell, and a secondary battery top cover 100 for sealing the case, wherein the secondary battery top cover 100 is welded to the case to be sealed, and a secondary battery electrolyte for infiltrating the battery cell is injected into the case. The secondary battery top cap 100 includes a top cap sheet 1, and a first electrode unit 3, a second electrode unit 2, a liquid injection hole 5, and an explosion-proof valve assembly 4 provided on the top cap sheet 1. The top cover plate 1 is provided with a first electrode introducing hole 11, a second electrode introducing hole 13 and an explosion-proof valve mounting hole 15, the first electrode introducing hole 11 is fixed with a first electrode unit 3 in an insulated way, and the second electrode introducing hole 13 is connected with a second electrode unit 2. The explosion-proof valve assembly 4 comprises an explosion-proof valve 41 and an explosion-proof valve protecting piece 43, the explosion-proof valve 41 is arranged in the explosion-proof valve mounting hole 15, and the explosion-proof valve protecting piece 43 is arranged above the explosion-proof valve 41. A lower insulator 6 is provided below the top cover plate 1 to electrically insulate the top cover plate 1 from the cells in the housing.

The first electrode unit 3 may be either a positive electrode unit or a negative electrode unit, as shown in the figure. As shown in fig. 3 to 7, the negative electrode unit 3 includes a negative electrode post 31 fixed to the first electrode introducing hole 11 in an insulating manner, an injection molding member 33 surrounding the negative electrode post 31 and insulating the negative electrode post 31 from the top lid plate 1, and a sealing member 35 interposed between the top lid plate 1 and the negative electrode post 31, wherein an upper portion of the sealing member 35 abuts against the top lid plate 1, and a side wall of the sealing member 35 abuts against the negative electrode post 31.

As shown in fig. 3 to 4 and fig. 10, the upper surface of the top cover plate 1 is recessed around the first electrode lead-in hole 11 to form a first groove 14, and the injection molding 33 is embedded in the first groove 14, so that the connection between the injection molding 33 and the top cover plate 1 can be improved by the arrangement of the first groove 14. Preferably, the upper surface of the top cover plate 1 is provided with a plurality of first notches 15 for the injection molded part 33 to be embedded into and communicated with the first groove 14, as shown in the figure, the number of the first notches 15 is 8, the 8 first notches 15 are regularly arranged around the first groove 14, and the projection shape of the first notch 15 in the vertical direction is an arc shape so as to facilitate filling of the raw material of the injection molded part 33. And the upper surface of the top cover plate 1 is provided with a second notch 16 for embedding the injection molding 33 around each first notch 15, the depth of the second notch 16 is smaller than that of the first notch 15, the projection shape of the second notch 16 in the vertical direction is an annular arc, and the peripheral wall of the second notch close to the first notch 15 is also a curved surface so as to facilitate the filling of the raw material of the injection molding 33. . The connection between the injection-molded part 33 and the top cover plate 1 is further secured and the rotation-proof effect is further enhanced by the arrangement of the first notch 15 and the second notch 16. The lower surface of the top cover sheet 1 is recessed around the first electrode introducing hole 11 to form a second groove 17, and the second groove 17 communicates with the first electrode introducing hole 11. The lower part of the top cover plate 1 is provided with a lower insulating part 6, the lower insulating part 6 is provided with a clamping part 61, and the clamping part 61 extends into the second groove 17 and is clamped in the cathode pole 31 so as to improve the firmness and compactness of connection between the secondary battery top cover parts.

As shown in fig. 3 to 9, the negative electrode post 31 includes a protruding portion 311 and a terrace portion 313 connected in the vertical direction, the terrace portion 313 is located at the lower portion of the first electrode introducing hole 11, and the terrace portion 313 and the protruding portion 311 constitute an inverted "T" type structure. The platform 313 and the extension 311 can be welded together by two metal blocks, the platform 313 and the extension 311 are usually made of aluminum for connecting to the outside, the platform 313 is made of copper, and the extension 311 can be a cylinder or a prism in general outline. The top of the protrusion 311 is provided with an upper step 3113, and the upper surface of the injection molded part 33 is flush with the lower step of the upper step 3113. The platform 313 is provided with a lower step 3131, the sealing member 35 abuts against the lower step 3131, and a sidewall portion of the sealing member 35 abuts against the platform 313 and a portion abuts against the protrusion 311. And the clamping portion 61 of the lower insulator 6 extends into the second groove 17 and is clamped to the lower step portion 3131.

Further as shown in fig. 3 to 9, in order to make the connection between the injection molded part 33 and the top cover plate 1 more reliable, the cathode post 31 faces the outer wall of the injection molded part 33 and is recessed in the middle to form an annular groove 3111, and the injection molded part 33 is clamped in the annular groove 3111. Meanwhile, a chamfer R is arranged at the joint of the groove bottom of the annular groove 3111 and the upper groove wall, and a stress buffer zone can be formed in the annular groove 3111 by the chamfer R, so that the pressure impact of the molten plastic on the upper region of the cathode post 31 is relieved, the deformation of the cathode post 31 region on the upper portion of the annular groove 3111 is avoided, and the sealing performance of the secondary battery top cover 100 is improved. The chamfer R can be a straight chamfer with an angle of 10-80 degrees, or the chamfer R is a circular arc chamfer of R0.1-R1.0. Preferably, the annular groove 3111 is provided on the protruding portion 311 penetrating the first electrode introducing hole 11, and the annular groove 3111 is formed by recessing the outer wall of the protruding portion 311. The projection shape of the groove bottom of the annular groove 3111 in the vertical direction is the same as the projection shape of the outer contour of the protruding portion 311 in the vertical direction. Because the junction of the groove bottom of the annular groove 3111 and the upper groove wall is provided with the chamfer R, and the contour of the groove bottom of the annular groove 3111 is consistent with the contour of the cathode post 31 above, the intensity of the upper part of the cathode post 31 is increased, and the deformation of the upper part of the cathode post 31 caused by the impact force of molten plastic is avoided.

The positive electrode unit 2 and the negative electrode unit 3 can be the same or different, both can be electrically insulated from the top cover sheet 1, the negative electrode unit 3 can be electrically insulated from the top cover sheet 1, and the positive electrode unit 2 is electrically connected with the top cover sheet 1. The positive electrode unit 2 and the negative electrode unit 3 can have the same structure, the second electrode unit 2 comprises a positive electrode pole 21 fixed in the second electrode lead-in hole 12 in an insulating mode, a positive electrode injection molding piece 23 arranged around the positive electrode pole 21 and used for insulating the positive electrode pole 21 from the top cover piece 1, and a positive electrode sealing piece 25 arranged between the top cover piece 1 and the positive electrode pole 21, the upper portion of the positive electrode sealing piece 25 abuts against the top cover piece 1, and the side wall of the positive electrode sealing piece 25 abuts against the positive electrode pole 21. The outer wall of the positive pole post 21 facing the positive pole injection molding piece 23 is recessed in the middle to form an annular groove 3111, the positive pole injection molding piece 23 is clamped in the annular groove 3111, and a chamfer R is arranged at the joint of the groove bottom of the annular groove 3111 and the groove wall of the upper portion. However, in order to solve the problems of overcharge and puncture of the secondary battery during the use of the secondary battery, the positive electrode unit 2 and the top cover sheet 1 are usually electrically conducted to form an external short circuit, so that when the positive electrode unit 2 is prepared by injection molding, conductive particles, such as conductive carbon or conductive metal, are added to the injection molding material to electrically connect the positive electrode post 21 and the top cover sheet 1. Of course, the positive electrode unit 2 and the negative electrode unit 3 may have different structures, and if necessary, the structures of the partial positive electrode seal 25, the partial positive electrode post 21, and the partial positive electrode injection molded part 23 may be adjusted so that the structures of the positive electrode unit 2 and the negative electrode unit 3 are not completely symmetrical.

It should be noted that the above-mentioned embodiments illustrate rather than limit the scope of the invention, and that modifications of various equivalent forms of the invention, which may occur to those skilled in the art after reading the present application, fall within the scope of the appended claims.

Claims

1. A secondary battery top cap, comprising: the utility model discloses a top cap piece, connection the first electrode unit and the second electrode unit of top cap piece, the top cap piece is equipped with first electrode and introduces the hole, a serial communication port, first electrode unit is fixed in including insulating first electrode is introduced the first utmost point post in hole and is enclosed to be located first utmost point post will first utmost point post with the insulating injection molding of top cap piece, first utmost point post towards the outer wall of injection molding forms the ring channel in the middle part indent, the injection molding joint in the ring channel, the tank bottom of ring channel is equipped with the chamfer with the department of meeting of upper portion cell wall.

2. The secondary battery top cap according to claim 1, wherein the chamfer is a straight chamfer having an angle of 10 ° to 80 °, or the chamfer is a rounded chamfer of R0.1 to R1.0.

3. The secondary battery top cap according to claim 1, wherein the first electrode post includes a protruding portion and a terrace portion connected in a vertical direction, the terrace portion is located at a lower portion of the first electrode introduction hole, the protruding portion penetrates the first electrode introduction hole and an outer wall is recessed inward to form the annular groove.

4. The secondary battery top cap according to claim 3, wherein a projected shape of the groove bottom of the annular groove in the vertical direction and a projected shape of the outer contour of the protrusion in the vertical direction are the same.

5. The secondary battery top cap according to claim 1, wherein the first electrode unit further comprises a sealing member interposed between the top cap sheet and the first electrode post, wherein an upper portion of the sealing member abuts against the top cap sheet, and a side wall of the sealing member abuts against the first electrode post.

6. The secondary battery top cap according to claim 1, wherein the upper surface of the top cap sheet is recessed around the first electrode introduction hole to form a first groove, and the injection molded member is inserted into the first groove.

7. The secondary battery top cap according to claim 6, wherein the top surface of the top cap sheet is provided with a plurality of first notches for the injection molding to be embedded in and communicated with the first grooves, and the plurality of first notches are regularly arranged around the first grooves.

8. The secondary battery top cap according to claim 7, wherein the upper surface of the top cap sheet is provided with a second notch around each of the first notches, and the second notch has a depth smaller than the first notch, and the second notch is embedded by the injection molding.

9. The secondary battery top cap according to claim 1, wherein a lower surface of the top cap sheet is recessed around the first electrode introduction hole to form a second groove, and the second groove communicates with the first electrode introduction hole.

10. The secondary battery top cover according to claim 9, wherein a lower insulating member is disposed at a lower portion of the top cover plate, the lower insulating member is provided with a clamping portion, and the clamping portion extends into the second groove and is clamped to the first pole.