| 摘要 |
PROBLEM TO BE SOLVED: To provide a porous film which is excellent in productivity, has high strength, a good electrolytic solution retaining property and is suitable for a separator for a lithium ion secondary battery, to provide a method of prepar ing the same and also a battery and capacitor which are prepared by using the same. SOLUTION: This porous film includes a high molecular weight polyolefin of 50-99 wt.% a macro-molecular electrolyte of 1-25 wt.% and other resins of 0-25 wt.%. Forty to hundred wt.% of the total amount of the high molecular weight polyolefin is composed of an ultrahigh molecular weight polyolefin having a weight average molecular weight of >=10×105. The method of preparing the same is provided. The battery and capacitor which are prepared by using the porous film are also provided. |
