Method for drying lithium ion battery or battery pole piece

Abstract

The invention discloses a method for drying a lithium ion battery or a battery pole piece. The method comprises the following steps: (1) high-pressure heating: raising the temperature in a working box in which an inner circulating fan is arranged to a first preset temperature within 20-60 minutes, raising the pressure in the working box to a first preset pressure by adopting protection gas, and keeping for 5-20 minutes; (2) vacuum water removal: keeping the temperature in the working box at the first preset temperature, vacuumizing till the absolute vacuum degree in the working box is 200-10pa, and reducing the moisture of the lithium ion battery or the battery pole piece to be treated to first preset moisture; (3) cooling: inputting cooling medium into the working box, and lowering the temperature of the lithium ion battery or the battery pole piece to a second preset temperature. By adopting the method, the temperature in the working box can be raised to the first preset temperature within 1 hour, and the heating time is 5-7 hours shorter than the conventional heating time, so that the aims of shortening the baking time and increasing the equipment utilization ratio can be fulfilled. Moreover, the moisture of the lithium ion battery or the battery pole piece can be further removed, and the capacity of the battery is increased.

Description

technical field [0001] The invention relates to a drying method of a lithium ion battery or battery pole pieces. Background technique [0002] At present, the manufacture of lithium-ion battery pole pieces or lithium-ion batteries requires deep drying of lithium-ion battery pole pieces or lithium-ion batteries. Most of the existing deep drying equipment adopts a single-box baking process. The most common The baking process is in a vacuum oven, first put the baked lithium battery electrode into the vacuum oven, and then heat the box, when the temperature in the box reaches the requirement, under the condition of heat preservation, put The box is vacuumed to remove moisture. When the moisture of the battery pole piece meets the requirements, the baked lithium battery electrodes or batteries in the box are naturally cooled or forced to cool, so that the baked lithium battery electrodes or batteries After the temperature drops to a certain level (generally below 35 degrees Ce...

AI Technical Summary

Problems solved by technology

The existing baking method generally takes about 24 hours to complete a drying cycle even if forced cooling is used from feeding to discharging. Therefore, this baking process has long baking time and low utilization rate of equipment The problem

In addition, the water content of the battery pole pieces baked by this method only reaches 400ppm-600ppm, which cannot meet the lower requirements and affects the further improvement of the battery capacity.

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