Tab forming method and device

Abstract

The invention provides a tab forming method and device. The tab forming method includes the steps of: providing a pole piece; performing round hole die-cutting along the longitudinal direction at the position where the root chamfer of the pole piece will be formed to form a pair of round holes penetrating through the pole piece, a pair of round holes The position corresponds to the two root chamfers of a pole lug; along the longitudinal direction, laser cutting is used to cut the pole piece between two adjacent pairs of round holes, and the longitudinal straight cutting line formed by the longitudinal straight line cutting is the same as that of the adjacent two pairs of round holes. The two inner circular holes in the circular holes intersect; the pole pieces are die-cut in a straight line along the horizontal direction, and each horizontal straight cutting line formed by the horizontal linear die-cutting runs from the lateral edge of the current collector to the corresponding one. The circular holes extend and intersect with the corresponding circular holes at the ends; the pole piece consists of each longitudinal straight cutting line, two circular holes intersecting the opposite ends of the longitudinal straight cutting line, and intersecting the two circular holes respectively The part enclosed by the transverse straight cutting line is cut off to form the tab.

Description

technical field [0001] The invention relates to the field of tabs, in particular to a tab forming method and device. Background technique [0002] In the lithium-ion battery manufacturing process, the tab forming process of the pole piece is a very important link in the entire battery production process. The pros and cons of the tab forming process and equipment technology will affect the flexibility and cost of manufacturing, the quality of the tab and the quality of the tab. Stability directly affects the electrochemical performance and safety performance of the battery. [0003] At present, there are two commonly used tab forming methods. [0004] One is mechanical die-cutting, which has the following problems: 1) A battery size needs a corresponding die-cutting mold, and it is difficult to share die-cutting molds with different battery sizes, and the flexibility is poor; 2) Limited Machining precision, die 2 and punch 1 (see figure 1 ) at the chamfer at the root of th...

AI Technical Summary

Problems solved by technology

[0004] One is mechanical die-cutting, which has the following problems: 1) A battery size needs a corresponding die-cutting mold, and it is difficult to share die-cutting molds with different battery sizes, and the flexibility is poor; 2) Limited Machining precision, die 2 and punch 1 (see figure 1 ) at the chamfer at the root of the lug ( figure 1 In the dotted circle area in the circle, the cooperation between the die 2 and the punch 1 is difficult to control, resulting in large burrs and serious powder loss of the active material of the pole piece. The battery made of such a pole piece has a large self-discharge, and even the battery catches fire. ;3) Mechanical die-cutting is based on the shear force of the die 2 and the punch 1, so the die 2 and the punch 1 are easily worn during use, resulting in poor quality stability; 4) Die wear is not conducive to the production line Continuous production, and mold maintenance and replacement are labor-intensive; 5) High mold cost and short life lead to increased manufacturing costs

[0005] The other is to form tabs by laser cutting alone, but this forming method also has inherent defects, which has led to the large-scale application of this method: 1) tab forming involves the active material layer 282 and the uncoated active material layer 282 The uncoated area 2812 (see figure 2 The uncoated area 2812 is used to form the lug 283), and laser forming is difficult to ensure that the quality of the two areas is optimal at the same time, especially in the transition area of ​​the two areas (the transition area R is the root of the tab) with large burrs and beads ;2) Laser forming needs to remove the dust generated by cutting. The blowing or exhausting airflow generally covers at least one tab-sized area. The large area leads to weak airflow, poor dust removal effect, burrs, molten beads and dust will cause the battery to self-destruct. Risk of large discharge or even fire

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