SEPARATOR FOR STORAGE BATTERY, AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a separator for storage battery improved in electrolytic solution permeability of a separator base material and set in a prescribed low electric resistance by paying attention and controlling in an appropriate range the factor which affects greatly the wettability of an inorganic powder, as a method of improving permeability (wettability) of the electrolytic solution of the separator base material to realize low electric resistance of the separator for storage battery made of fine porous film consisting mainly of polyolefin resin and inorganic powder, and a manufacturing method of the separator for storage battery. SOLUTION: This is a separator for storage battery which is composed of a fine porous film that is obtained by forming in sheet shape by heat melting and kneading a raw material composition made mainly of polyolefin resin, inorganic powder, and a plasticizer and removing a part or whole of the plasticizer and which uses an aqueous electrolytic solution. The inorganic powder has pH 6.5 or less. COPYRIGHT: (C)2005,JPO&NCIPI