Patent ID: 6627346
Filing Date: 2003-09-30
Classification: H01M,Y02E

Abstract:
A battery separator comprising one porous resin film containing no solid particles and a pair of porous resin films in which 100 to 40,000 ppm of solid particles having a mean diameter in the range of 0.1 to 10 &mgr;m are dispersed in a porous resin matrix, the solid particles comprising at least one metal oxide selected from the group consisting of silicon dioxide, aluminum oxide, magnesium oxide, zinc oxide, and metal oxides containing at least two metal elements selected from the group consisting of Si, Al, Mg and Zn and having an oxidation potential of +4.5V or more as compared with that of lithium, under the condition that the porous resin film containing no solid particles is placed between the pair of porous resin films having the particles of metal oxide.