Tab short-circuit-proof method of soft package lithium battery

Abstract

The invention discloses a tab short-circuit-proof method of a soft package lithium battery. The tab short-circuit-proof method comprises the following steps: step 101, carrying out positive electrode tab treatment: selecting tab glue, wherein the tab glue is one of black glue, white glue or yellow glue; firstly, forming an insulating layer on the surface of a positive electrode tab base body by utilizing a natural color anodic oxidization, black anodic oxidization or micro-arc oxidization method, wherein the thickness of the insulating layer is no smaller than 10 microns; measuring surface insulating resistance by a 500V insulating resistance meter, wherein the surface insulating resistance needs to be more than 200 megohms; then casting the tab glue on the positive electrode tab base body in a curtain coating way; cutting a positive electrode tab to a required size; finally, carrying out oxidation layer removal treatment on two ends of the tab by utilizing a chemical method; step 102, assembling a single battery: specifically, firstly, welding the tab; then packaging the battery; vacuumizing and sealing, and standing for more than 24h; observing whether leakage exists or not; cutting apart a single battery side plate, injecting liquid, aging and standing; finally, vacuumizing and carrying out secondary package on the single battery in a final state.

Description

technical field [0001] The invention relates to the technical field of chemical power sources, in particular to a method for preventing short-circuiting of tabs of soft-packaged lithium batteries. Background technique [0002] Soft-packed lithium batteries are widely used in lithium-ion batteries and lithium primary batteries due to their high specific energy and simple manufacturing process. For example, lithium batteries for mobile phones and lithium batteries for some power vehicles all use soft-packed structures. It is characterized in that the battery cell and electrolyte are packaged in aluminum-plastic film packaging bags, the positive pole tab is aluminum tab with glue, the negative pole tab is nickel-coated or copper or copper-plated nickel tab, and the aluminum-plastic film is heat-sealed. , the glue at the tab is heated and melts into the PE layer in the aluminum-plastic film as an insulating layer between the positive and negative tabs and the aluminum-plastic fi...

AI Technical Summary

Problems solved by technology

It is characterized in that the battery cell and electrolyte are packaged in aluminum-plastic film packaging bags, the positive pole tab is aluminum tab with glue, the negative pole tab is nickel-coated or copper or copper-plated nickel tab, and the aluminum-plastic film is heat-sealed. , the glue at the tab is heated and melts into the PE layer in the aluminum-plastic film as an insulating layer between the positive and negative tabs and the aluminum-plastic film. The thickness of the insulating layer is less than 1mm, and due to the limitation of the heat sealing process, it is difficult to form Insulation layer of uniform thickness

The tab part is the weak link in the reliability of the battery. High temperature or excess metal is likely to form a short circuit at the sealing part of the tab, resulting in battery failure or even safety accidents.

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