SYNTHETIC RESIN MICROPOROUS FILM, SEPARATOR FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a synthetic resin microporous film which can be used as a separator for a nonaqueous electrolyte secondary battery and hardly causes oxidative degradation even when the charge termination voltage of a nonaqueous electrolyte secondary battery is set high.SOLUTION: There is provided a synthetic resin microporous film which comprises a synthetic resin microporous substrate film having a micropore part and a film layer which is formed on the surface of the synthetic resin microporous substrate film and on the wall face of the micropore part and contains a polyamide-imide, wherein the synthetic resin microporous film has high potential resistance and oxidative degradation is suppressed even when a high potential is applied to the synthetic resin microporous film.SELECTED DRAWING: None