| 摘要 |
PROBLEM TO BE SOLVED: To reduce the possibility of occurrence of thermal runaway during heating, in a nonaqueous secondary battery housing a power generation element in a flexible package sheet without increasing the thickness of the battery.SOLUTION: A power generation element 5, in which a sheet-like positive electrode 12p is inserted into a valley folded portion on one side of a strip separator 11 folded in zigzag and a sheet-like negative electrode 12n is inserted into a valley folded portion on the other side, is housed in a flexible package sheet 2. The separator has a porous layer 11a composed of a hot-melt resin, and an insulation layer 11b containing insulating inorganic particles formed on one surface of the porous layer. At both ends 17 of the separator in the width direction, the porous layers facing each other are heat-welded. |
