| 摘要 |
PURPOSE: To provide a separator having desirable battery assembly properties as a separator, sufficiently excellent electrolyte impregnating property, low electric resistance, and safety, and remarkably improved mechanical strength not only in the direction of a machine but also in the width direction. CONSTITUTION: A battery separator is made of a finely porous membrane produced from a mixture material containing 10-60wt.% of polyethylene with 1,000,000 or more viscosity-average molecular weight, 10-60wt.% of polyethylene with 100,000-1,000,000 viscosity-average molecular weight, and 10-40wt.% of ethylene-propylene rubber. Two or more sheets of the finely porous membrane are laminated. |
