Liquid storage type flexible package lithium ion battery cell and method for preparing batteries

Abstract

The invention discloses a liquid storage type flexible package lithium ion battery cell and a method for preparing batteries. The method includes welding tabs with tab adhesive on pole pieces; arranging diaphragms between anode pieces and cathode pieces; winding the anode pieces, the cathode pieces and diaphragms to obtain wound cells; mounting top modules and bottom modules of liquid storage devices at the tops and the bottoms of the wound cells to obtain the liquid storage type flexible package lithium ion battery cell. Gaps between the tab adhesive and the pole pieces range from 4 millimeters to 11 millimeters. Anode tabs are welded on the anode pieces, cathode tabs are welded on the cathode pieces, and the distances from the edge of the tab adhesive to the edges of the diaphragms range from 3 millimeters to 10 millimeters. The liquid storage type flexible package lithium ion battery cell and the method have the advantage that the performance of the batteries can be enhanced.

Description

technical field [0001] The invention relates to the technical field of lithium ion batteries, in particular to a liquid storage type flexible packaging lithium ion battery cell and a preparation method of the battery. Background technique [0002] In recent years, as a kind of secondary battery, flexible packaging lithium-ion battery has been used more and more widely, and the performance requirements of the battery are also getting higher and higher. [0003] The current structure of the cell is to coat the pole piece with a separator and put it directly into the shell. After the battery is vacuum-sealed, there is very little electrolyte left in the cell, and most of the electrolyte is inside the pole piece and on the surface of the separator. , As the number of charge and discharge of the battery increases, part of the electrolyte will lose its activity. If there is no excess electrolyte replenished in time, the performance will change, the capacity will decrease, and the ...

AI Technical Summary

Problems solved by technology

[0003] The currently used cell structure is to wrap the pole piece with a diaphragm and put it directly into the shell. After the battery is vacuum-packed, there is little electrolyte left in the cell, and most of the electrolyte is inside the pole piece and on the surface of the diaphragm. , as the number of charge and discharge of the battery cell increases, part of the electrolyte will lose its activity. In the absence of excess electrolyte replenishment in time, the performance will change accordingly, the capacity will decrease, and the internal resistance will increase, especially for the battery pack. The performance is more obvious, and the mileage is significantly reduced after repeated use

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