| 摘要 |
PROBLEM TO BE SOLVED: To provide a separator for a lithium ion secondary battery, which prevents short-circuit of a battery caused by the growth of a needle crystal and has superior ion conductivity, and a lithium ion secondary battery equipped with the separator.SOLUTION: The separator 10 for the lithium ion secondary battery includes a laminated body including a plurality of laminated uniaxial stretched films 11, 12, 13, 14, 15, and 16 having a number of micropores 11a, 12a, 13a, 14a, 15a, and 16a wherein the micropores 11a, 12a, 13a, 14a, 15a, and 16a have shapes with directionality and are stretched in a single direction. Out of the plurality of uniaxial stretched films 11, 12, 13, 14, 15, and 16 making up the laminated body, at least two overlapping uniaxial stretched films have micropores of which the direction of orientation cross each other between the two films. |
