HIGH TEMPERATURE-RESISTANT ARAMID LITHIUM-ION BATTERY COMPOSITE SEPARATOR AND MANUFACTURING METHOD THEREFOR

摘要

The present invention relates to the technical field of lithium-ion battery materials. Disclosed are a high temperature-resistant aramid lithium-ion battery composite separator and a manufacturing method therefor. The present invention comprises a base film and a coating coated on a single side or both sides of the base film. The coating is an aramid coating. The aramid coating is prepared with the following raw materials in terms of weight percent: aramid 1-6%, a pore forming agent 5-12%, inorganic ceramic particles 0.5-5%, and an organic solvent 77-93.5%. The aramid is extracted from an aramid polymer. The content of aramid in the aramid polymer is 10-30% in terms of weight percent. The coating and the base film of the present invention have great interface adhesion, the coating is not prone to falling off in extended and high intensity use conditions, the breathability value and pore diameter are adjustable, the thermal resistance, electrolyte wettability, and penetration strength are effectively increased, thus enhancing the safety performance of the lithium-ion battery separator. The present invention employs a non-solvent phase inversion method for gel film formation, has a simple and controllable process, and is easy to be produced in batch and continuously.