To substantially increase the capacity of a lithium ion battery and to miniaturize the battery by making a separator of a polyester film having the specified thickness, specifying the major axis and the minor axis of pores, and specifying the porosity.
A film is made of a polyester film having a thickness of 0.5-20 μm, having pores with minor axis ≤1.5 μm and major axis ≤6 μm, and having a porosity of ≥5%. Preferably, the film contains ≤80 wt.% polyester as the main component, and has a melting point of 240-280°C. Preferably, the film is made of a polyamide film or a polyimide film, having pores with minor axis ≤1.5μm and major axis ≤6μm, and having a porosity ≥5%, and contains ≥40 wt.% aromatic polyamide or aromatic polyimide as the main component. Preferably, the film is used together with an electrolyte not igniting at 100°C at the lowest.
| WO/2014/097919 | POLYETHERIMIDE POROUS BODY AND METHOD FOR PRODUCING SAME |
| WO/2017/026424 | POROUS PARTICLE, METHOD FOR PRODUCING POROUS PARTICLE, AND BLOCK COPOLYMER |
| WO/2017/082270 | CONDUCTIVE FILM |
TANAKA HIROYUKI
TSUKUDA AKIMITSU
