| 摘要 |
PROBLEM TO BE SOLVED: To provide a microporous polyolefin-based diaphragm capable of ultimately improving charge and discharge efficiency of a secondary battery by preventing formation of a dendrite around a negative electrode, and of improving a battery life and having a new structure; and to provide its manufacturing method. SOLUTION: In this microporous polyolefin-based diaphragm for a secondary battery, pores each having a size of 80 nm to 2μm are distributed 90-97% in a negative electrode-side surface layer, and pores each having a size of 30 nm to 1μm are distributed 90-97% in a positive electrode-side surface layer. COPYRIGHT: (C)2007,JPO&INPIT |
