CN-224232887-U - Structure of hidden aluminum-nickel-to-polar ear

Abstract

The utility model belongs to the technical field of lithium ion batteries, and particularly relates to an invisible aluminum-nickel conversion tab structure, which comprises an aluminum tab and a nickel connecting sheet, wherein an embossing structure matched with each other is arranged in a connecting area of the aluminum tab and the nickel connecting sheet, the embossing structure enables the aluminum tab and the nickel connecting sheet to form mechanical interlocking, and a tab adhesive fault prevention layer is arranged at an interface of the connecting area. According to the utility model, through the composite structure design of embossing interlocking, tab glue breaking prevention and welding reinforcement, the mechanical strength and the shock resistance of an aluminum-nickel interface are obviously improved.

Inventors

• MAN YANYAN
• SONG YUJIA
• MAO XUEJIAO
• ZHANG HONGFANG
• LI HE

Assignees

• 天津力神聚元新能源科技有限公司
• 天津力神电池股份有限公司

Dates

Publication Date

20260512

Application Date

20250605

Claims (10)

1. 1. The utility model provides a stealthy aluminium changes nickel utmost point ear structure, its characterized in that includes aluminium utmost point ear and nickel connection piece, aluminium utmost point ear with the connected region of nickel connection piece is equipped with the embossing structure of mutual matching, embossing structure makes aluminium utmost point ear with nickel connection piece forms mechanical interlock, and be equipped with utmost point ear glue fault-proof layer in the interface department of connected region.
2. 2. The stealth aluminum-nickel tab construction of claim 1 wherein the embossed structure is wave-shaped, zigzag-shaped or grid-shaped.
3. 3. The invisible aluminum-nickel converting tab structure according to claim 1, wherein the connection area of the aluminum tab and the nickel connecting piece is welded to form a welding spot, and the welding spot is positioned in a buffer area for connecting tab glue and a metal belt.
4. 4. The invisible aluminum-nickel converting tab structure according to claim 1, wherein the thickness of the tab glue anti-fault layer is 10-50 μm, the glue dispensing width is consistent with the width of the aluminum tab, and the glue dispensing length L is more than or equal to 0.1mm.
5. 5. The invisible aluminum-nickel converting tab structure according to claim 1, wherein the aluminum tab and the nickel connecting piece are fixed by laser welding or ultrasonic welding, and a welding area is located in an overlapping range of the embossed structure.
6. 6. The invisible aluminum-nickel converting tab structure according to claim 1, wherein the overlapping width of the aluminum tab and the nickel connecting sheet is not less than 3mm.
7. 7. The stealth aluminum-nickel tab structure of claim 1, wherein the height H of the embossed structure is 0.1-2 tab thickness.
8. 8. The invisible aluminum-to-nickel tab structure according to claim 1, wherein the tab glue is fault-proof coated between the nickel connection tab fracture and the contact surface of the aluminum tab.
9. 9. The stealth aluminum-to-nickel tab structure of any one of claims 1-8, wherein the aluminum tab thickness is 0.08-0.5mm and the nickel connecting tab thickness is 0.08-0.5mm.
10. 10. The stealthy aluminium changes nickel utmost point ear structure of claim 5, wherein, the welding area outside is equipped with oxidation preventing layer or insulating parcel layer.

Description

Structure of hidden aluminum-nickel-to-polar ear Technical Field The utility model belongs to the technical field of lithium ion batteries, and particularly relates to a hidden aluminum-nickel tab structure. Background In the manufacturing process of lithium ion batteries, it is generally necessary to weld and connect an aluminum tab (positive electrode) with a nickel tab (external conductive tab). However, aluminum and nickel have large differences in physical properties (e.g., coefficient of thermal expansion, hardness, ductility, etc.), resulting in failure by fracture after welding, which is prone to mechanical shock (e.g., battery drop). In the prior art, the main connection mode of the aluminum-nickel tab comprises direct laser welding, ultrasonic welding, riveting or mechanical crimping and the like. The direct laser welding interface is easy to form brittle intermetallic compound, is easy to break when falling, has limited ultrasonic welding strength, can crack after long-term vibration or impact, and can introduce extra resistance to influence the battery performance. The main problems in the prior art are that the strength of an aluminum-nickel welding interface is insufficient, the stress of a welding area is concentrated, a buffer mechanism is lacked, and the problem of tab fracture caused by drop impact cannot be effectively solved. Disclosure of utility model The utility model aims to provide a hidden aluminum-nickel tab structure, which solves the problems in the prior art. In order to achieve the purpose, the technical scheme is that the invisible aluminum-nickel conversion tab structure comprises an aluminum tab and a nickel connecting sheet, wherein an embossing structure matched with each other is arranged in a connecting area of the aluminum tab and the nickel connecting sheet, the embossing structure enables the aluminum tab and the nickel connecting sheet to form mechanical interlocking, and a tab adhesive anti-fault layer is arranged at an interface of the connecting area. Preferably, the embossed structure is in the form of waves, serrations or grids. Preferably, the connection area of the aluminum tab and the nickel connecting sheet is welded to form a welding spot, and the welding spot is positioned in a buffer area for connecting tab glue and a metal belt. Preferably, the thickness of the tab glue anti-fault layer is 10-50 mu m, the glue dispensing width is consistent with the width of the aluminum tab, and the glue dispensing length L is more than or equal to 0.1mm. Preferably, the aluminum tab and the nickel connecting sheet are fixed by laser welding or ultrasonic welding, and the welding area is located in the overlapping range of the embossed structure. Preferably, the overlapping width of the aluminum tab and the nickel connecting sheet is more than or equal to 3mm. Preferably, the height H of the embossed structure is 0.1-2 times the thickness of the tab. Preferably, the tab glue anti-fault coating is applied between the fracture of the nickel connecting sheet and the contact surface of the aluminum tab. Preferably, the thickness of the aluminum tab is 0.08-0.5mm, and the thickness of the nickel connecting sheet is 0.08-0.5mm. Preferably, an oxidation preventing layer or an insulating wrapping layer is arranged outside the welding area. The utility model has the beneficial effects that the mechanical strength and the shock resistance of an aluminum-nickel interface are obviously improved through the composite structure design of embossing interlocking, tab glue breaking prevention and welding reinforcement. The anti-fault tab glue layer is filled between the fracture of the nickel connecting sheet and the aluminum tab by adopting flexible materials (such as silica gel and polyimide glue), so that falling impact energy can be effectively absorbed, crack expansion caused by rigid impact is prevented, the bending frequency of the tab is improved by more than 1 time, and the passing rate of a 1.8m falling test is improved from 60% to 100% of that of the traditional structure. The structure has the advantages of process compatibility and cost. The embossing and stamping process is mature, the consumption of tab glue is small and the tab glue is coated inside, the battery assembly process is not affected, the existing production line is not required to be greatly adjusted, the stealth design wraps the welding area through the insulating material, the electric insulation is realized, meanwhile, the appearance is kept clean, and the whole cost is limited. Through testing, the voltage drop of the embodiment tab after 72 times of 1.8m drop tests is only 0.003-0.009V, which is far lower than 0.089V of the traditional tab, and the advantages of remarkably improving the reliability while maintaining the conductivity are verified. Drawings FIG. 1 is a schematic view of the welded overall structure of the present utility model; FIG. 2 is an enlarged view of FIG. 1 at A; FIG. 3 is a schema