| 摘要 |
PROBLEM TO BE SOLVED: To obtain a separator which is excellent in impregnating properties and liquid-holding properties of an electrolytic solution and which does not hinder the ion conductivity.SOLUTION: A separator comprises a functional resin layer containing a resin material and an inorganic oxide filler, having a porous interconnected structure in which many pores are mutually interconnected and having a contact angle against an electrolytic solution of 11 degrees or below. When the central particle diameter and the specific surface area of the inorganic oxide filler are defined as X [μm] and Y [m/g], respectively, a value obtained by multiplying X by Y preferably falls within the range of 1≤X×Y≤18. The functional resin layer preferably contains at least a heat-resistant resin, and more preferably contains at least a fluorine-based resin. |
