SEPARATOR AND ITS MANUFACTURING METHOD AND NONAQUEOUS BATTERY USING THE SAME

摘要

PROBLEM TO BE SOLVED: To solve problems of a finely porous separator that the reaction on an electrode surface is not uniform and the lifetime characteristic of a battery is deteriorated because of a wide variation of hole shapes on the surface resulting from chemically formed holes, and that high-rate discharging characteristic is also deteriorated arising from a complexity of moving paths of Li ions inside the separator. SOLUTION: A woven fabric composed of polypropylene fibers is processed by hot press, or a polyolefin film is processed by laser irradiation or machining for forming holes, thereby the separator having holes with almost uniform shapes and less dispersion of thickness can be obtained. The reaction on the electrode surface becomes uniform by this separator and lifetime characteristic is improved. Further, the moving paths of the Li ions inside the separator become shorter, thereby the high-rate discharging characteristic is improved.