| 摘要 |
PROBLEM TO BE SOLVED: To provide a power storage element which can improve heat resistance and can restrain a reduction in output at the same time.SOLUTION: The power storage element comprises a porous base material having electrical insulation properties and an inorganic material layer disposed on at least one surface side of the porous base material and including tabular and spherical inorganic particles. In the thickness direction cross section of the inorganic material layer, an area ratio P1 occupied by the spherical inorganic particles relative to an area occupied by the tabular inorganic particles in a range from the interface with the porous base material to 1/3 of the thickness and an area ratio P2 occupied by the spherical inorganic particles relative to an area occupied by the tabular inorganic particles in other than that satisfy the relationship in which the ratio P1 is 0.01 or greater and 10 or less, and in which a ratio of P1 to P2, P1/P2, is 1.1 or greater and 50 or less. |
