CN216624504U

CN216624504U - Full-lug cylindrical lithium ion battery

Info

Publication number: CN216624504U
Application number: CN202122277303.6U
Authority: CN
Inventors: 马振华; 赵斯琦; 赵悠曼
Original assignee: Dongguan Chuangming Battery Technology Co Ltd
Current assignee: Dongguan Chuangming Battery Technology Co Ltd
Priority date: 2021-09-16
Filing date: 2021-09-16
Publication date: 2022-05-27
Anticipated expiration: 2031-09-16

Abstract

The utility model discloses a full-lug cylindrical lithium ion battery which comprises an anode current collecting disc, a cathode current collecting disc and a winding core which is positioned between the anode current collecting disc and the cathode current collecting disc and is of a full-lug structure, wherein the anode current collecting disc comprises an insulating part and an aluminum sheet, the insulating part comprises a bottom and a side part which is bent and extended along the circumferential direction of the bottom, the aluminum sheet is arranged in a cavity formed by the bottom and the side part, the bottom is hollow and can expose the aluminum sheet, and the aluminum sheet is provided with a laser welding area. In the full-lug cylindrical lithium ion battery, a positive current collecting disc is connected with a winding core through laser welding; the negative electrode current collecting disc is connected with the winding core through laser welding, and is connected with the shell in a resistance spot welding mode, so that the short circuit caused by the contact of the winding core and the shell can be effectively avoided, and meanwhile, the connection strength of the winding core and the shell can be ensured.

Description

Full-lug cylindrical lithium ion battery

Technical Field

The utility model relates to the technical field of lithium ion batteries, in particular to a full-lug cylindrical lithium ion battery.

Background

In the production and manufacturing process of the prior cylindrical lithium ion battery, the production and manufacturing process of a positive electrode single-pole lug, a negative electrode single-pole lug or a double-pole lug is mature. However, due to the defects of the tab leading-out design, the current distribution and the temperature field distribution inside the cylindrical battery cell are not uniform, and the battery cell is easy to lose effectiveness or induce safety problems due to excessive local current or high temperature in the use process of the battery cell. In order to reduce or avoid the above problems, for the design of the cylindrical lithium ion battery cell, developers are trying to design a multi-tab and full-tab cell to improve the current and temperature distribution inside the cell. However, although different solutions for designing the full tab can be used for realizing the assembly of the winding core and the manufacturing of the battery cell, the connection strength between the winding core and the shell after assembly, the possibility of short circuit caused by the contact between the winding core and the shell, the operation simplicity of the assembly process, the matching performance of the subsequent liquid injection sealing process and the like are still lack of overall process solutions.

Therefore, it is necessary to develop a full-tab cylindrical lithium ion battery to solve the above-mentioned drawbacks.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a full-lug cylindrical lithium ion battery capable of avoiding short circuit between a winding core and a shell.

In order to achieve the purpose, the utility model discloses a full-lug cylindrical lithium ion battery which comprises a positive current collecting disc, a negative current collecting disc and a winding core which is located between the positive current collecting disc and the negative current collecting disc and is of a full-lug structure, wherein the positive current collecting disc comprises an insulating part and an aluminum sheet, the insulating part comprises a bottom and a side part which is bent and extended along the circumferential direction of the bottom, the aluminum sheet is arranged in a cavity formed by the bottom and the side part, the bottom is hollow and can be exposed out of the aluminum sheet, and the aluminum sheet is provided with a laser welding area; the positive electrode current collecting disc is connected with the winding core through laser welding, the negative electrode current collecting disc is connected with the winding core through laser welding, and the mode of resistance spot welding is adopted to be connected with the shell.

Compared with the prior art, the utility model provides the full-lug cylindrical lithium ion battery, the aluminum sheet is arranged in the cavity formed by the bottom and the side part, when the anode current collecting disc is welded with the winding core, the anode lug end of the winding core faces the concave side of the insulating part, and when laser welding is carried out, the laser welding area of the aluminum sheet is used for carrying out circumferential welding with the anode lug of the winding core, and the insulating part is made of insulating materials, so that the short circuit caused by the contact between the anode lug of the winding core and the shell can be avoided, namely the short circuit between the winding core and the shell is avoided. Meanwhile, the anode current collecting disc is connected with the winding core and the shell in a welding mode, so that the enough connection strength of the winding core and the shell can be ensured.

Preferably, one side of the side part close to the bottom part is provided with a groove for mounting the aluminum sheet.

Preferably, the middle part of the aluminum sheet is provided with a first through hole and a plurality of second through holes for electrolyte to permeate.

Preferably, the thickness of the aluminum sheet is 0.1mm-0.2 mm.

Preferably, the aluminum tab is further included, one end of the aluminum tab is welded on the aluminum sheet, and the other end of the aluminum tab is welded with the cover plate.

Preferably, the thickness of the aluminum tab is 0.1mm-0.2 mm.

Preferably, the insulating part is made of PP or PTFE.

Preferably, the negative current collecting plate comprises a body portion, the body portion is provided with a plurality of laser welding spot areas and a plurality of through hole groups for electrolyte to permeate, and the through hole groups are arranged between two adjacent laser welding spot areas.

Preferably, the through hole group is composed of a plurality of through hole units arranged at intervals in the radial direction of the body part.

Preferably, the body portion has an embossed portion in the middle thereof.

Drawings

Fig. 1 is a schematic structural view of a positive current collecting plate according to the present invention.

Fig. 2 is a schematic structural view of another angle of the positive current collecting plate according to the present invention.

Fig. 3 is a schematic view showing the structure of an anode current collecting plate according to the present invention.

Fig. 4 is a schematic view showing the assembly of the winding core and the positive current collecting plate according to the present invention.

Description of the symbols:

positive current collecting plate 100, insulating part 10, bottom part 11, second through hole 113, side part 13, groove 131, cavity 15, aluminum sheet 30, laser welding area 31, first through hole 33, aluminum tab 50, negative current collecting plate 200, body part 20, laser welding spot area 21, through hole group 23, through hole unit 231, embossing part 25, and winding core 300.

Detailed Description

In order to explain the technical contents, structural features, objects and effects of the present invention in detail, the following description is made in conjunction with the embodiments and the accompanying drawings.

Referring to fig. 1-2, the present invention discloses a full-tab cylindrical lithium ion battery, which includes an anode current collecting disc 100, an anode current collecting disc 200, and a winding core 300 located between the anode current collecting disc 100 and the anode current collecting disc 200 and having a full-tab structure, wherein the anode current collecting disc 100 includes an insulating part 10 and an aluminum sheet 30, the insulating part 10 includes a bottom 11 and a side part 13 extending along the circumferential direction of the bottom 11, the aluminum sheet 30 is installed in a cavity 15 formed by the bottom 11 and the side part 13, the bottom 11 is hollow and can expose the aluminum sheet 30, the aluminum sheet 30 is provided with a laser welding area 31, and the anode current collecting disc 100 is connected with the winding core 300 through laser welding; anode current collecting plate 200 is connected to winding core 300 by laser welding.

In the above technical solution, referring to fig. 1-2, the insulating portion 10 is made of PP or PTFE, and has a thickness less than 0.5mm, and the bottom portion 11 and the side portion 13 are integrally formed to obtain the insulating portion 10. The inner circumference of the insulating part 10 is provided with a groove 131 for mounting the aluminum sheet 30, and specifically, one side of the side part 13 near the bottom part 11 is provided with a groove 131 for mounting the aluminum sheet 30. Through the cooperation installation of recess 131 and aluminum sheet 30, the assembly is simple and convenient, reduces the use gluing agent such as glue and probably brings the adverse effect to the battery.

In the above technical solution, please refer to fig. 1-2, the thickness of the aluminum sheet 30 is 0.1mm-0.2 mm. The middle of the aluminum sheet 30 is provided with a first through hole 33 for electrolyte to permeate, the hole diameter of the first through hole 33 is 2-4mm, a plurality of second through holes 113 for electrolyte to permeate are uniformly formed on the circumference 3mm away from the outer edge of the first through hole 33, preferably, the bottom 11 is provided with a plurality of second through holes 113 for electrolyte to permeate, the number and the diameter of the holes of the second through holes 113 can be adjusted according to the diameter of the winding core, so that the liquid permeating effect can be adjusted, and the limitation is not performed.

In the above technical solution, referring to fig. 1-2, the full-tab cylindrical lithium ion battery further includes an aluminum tab 50, wherein one end of the aluminum tab 50 is welded to the aluminum sheet 30, and the other end of the aluminum tab 50 is welded to a cover plate (not shown). Specifically, an aluminum tab 50 is welded and led out of the surface of the aluminum sheet 30 outside the cavity, the aluminum tab 50 is welded at one end of the aluminum sheet 30 and is circular, a hole is formed in the center, the diameter of the hole is the same as that of the first through hole 33 of the aluminum sheet 30, the thickness of the aluminum tab 50 is 0.1mm-0.2mm, the width of the aluminum tab is larger than or equal to 3mm, the length of the aluminum tab 50 can be adjusted according to the actual process, and the other end of the aluminum tab 50 is welded with the cover plate.

In the above technical solution, referring to fig. 3, an anode current collecting plate 200 includes a body portion 20, a plurality of laser welding spot regions 21 and a plurality of through hole groups 23 for electrolyte to permeate are disposed on the body portion 20, and the through hole group 23 is disposed between two adjacent laser welding spot regions 21. Further, the material of the body portion 20 may be nickel or nickel-plated copper, the thickness of the body portion 20 is 0.08-0.12mm, and the middle portion of the body portion 20 is provided with an embossed portion 25 for embossing, which is advantageous to resistance spot welding. In this embodiment, the body 20 is provided with the through hole groups 23 at every 90 degrees along the radial direction, so as to facilitate the penetration of the electrolyte. Preferably, the through-hole group 23 is composed of a plurality of through-hole units 231 arranged at intervals in the radial direction of the body part 20. Preferably, the shape of the through hole unit 231 may be a circle, an ellipse, a rectangle, a trapezoid, or the like. Preferably, the laser welding spot area 21 is the angular bisector position of the radial two-through hole group 23, and the welding spot may be one row or several rows of linear welding spots. The completely welded anode current collecting disc 200 and the completely welded cathode current collecting disc 100 are placed in a cylindrical steel shell, so that firm welding between the all-lug-structured winding core 300 and the shell can be realized, and the risks of internal resistance fluctuation and failure of battery cell safety performance testing caused by shaking of the winding core in the actual use process are avoided.

Compared with the prior art, this application provides a full utmost point ear cylinder lithium ion battery, install aluminum sheet 30 in the cavity 15 that bottom 11 and lateral part 13 formed, when welding positive pole current collector 100 with roll up core 300 (please refer to fig. 4), roll up the anodal ear end of core towards the concave side of insulating part 10, during laser welding, carry out circumferential weld with rolling up the anodal ear of core with the help of aluminum sheet 30's laser welding region 31, because insulating part 10 is insulating material, so can avoid rolling up the anodal utmost point ear of core and casing contact and take place the short circuit, avoid rolling up core and casing to take place the short circuit promptly. Meanwhile, since the anode current collecting disk 200 is connected to the winding core 300 and the case in a welding manner, the sufficient connection strength between the winding core 300 and the case can be ensured.

The above disclosure is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the scope of the present invention, therefore, the present invention is not limited by the appended claims.

Claims

1. The utility model provides a full utmost point ear cylinder lithium ion battery, includes anodal current collecting disc, negative pole current collecting disc and is located anodal current collecting disc with between the negative pole current collecting disc roll up the core that is full utmost point ear structure, its characterized in that, anodal current collecting disc includes insulating part and aluminum sheet, insulating part includes the bottom and follows the lateral part that bottom circumference is buckled and is extended, the aluminum sheet is installed the bottom with the cavity that the lateral part formed, the bottom cavity can expose the aluminum sheet, the aluminum sheet is equipped with the laser welding region, anodal current collecting disc pass through laser welding with roll up the core and be connected; the negative electrode current collecting disc is connected with the winding core through laser welding.

2. The full-tab cylindrical lithium ion battery of claim 1, wherein a side of the side portion adjacent to the bottom portion is provided with a groove for mounting the aluminum sheet.

3. The full-tab cylindrical lithium ion battery according to claim 1, wherein the aluminum sheet is provided at a middle portion thereof with a first through hole and a plurality of second through holes for penetration of an electrolyte.

4. The full-tab cylindrical lithium ion battery of claim 1, wherein the aluminum sheet has a thickness of 0.1mm to 0.2 mm.

5. The full-tab cylindrical lithium ion battery of claim 1, further comprising an aluminum tab, wherein one end of the aluminum tab is welded to the aluminum sheet, and the other end of the aluminum tab is welded to the cover plate.

6. The full-tab cylindrical lithium ion battery of claim 5, wherein the aluminum tab has a thickness of 0.1mm to 0.2 mm.

7. The full-tab cylindrical lithium ion battery of claim 1, wherein the negative current collector comprises a body portion, wherein a plurality of laser welding spot areas and a plurality of through hole sets for electrolyte to permeate are disposed on the body portion, and the through hole sets are disposed between two adjacent laser welding spot areas.

8. The full-tab cylindrical lithium ion battery of claim 7, wherein the via group is composed of a plurality of via units arranged at intervals in a radial direction of the body portion.

9. The full-tab cylindrical lithium ion battery of claim 7, wherein the body portion has an embossed portion embossed in the middle thereof to be connected to the case by resistance spot welding.