| 摘要 |
PROBLEM TO BE SOLVED: To provide a separator excellent in shutdown characteristics, and a highly safe lithium-ion secondary battery using the separator.SOLUTION: A separator 30 includes a first porous layer 31 made of polypropylene and a second porous layer 32 made of polyethylene. The separator 30 also includes composite oxide particles 36 containing Ca, Na, Al, and Si between the first porous layer 31 and the second porous layer 32. |
