| abstract |
A separator for a power storage device, comprising: a substrate including at least a porous film; and a thermoplastic polymer disposed on at least one surface of the substrate, wherein the area ( Si ) of the Voronoi polygon obtained by performing Voronoi splitting on the thermoplastic polymer is Wherein the dispersion (? 2 ) defined by the following formula is not less than 0.01 and not more than 0.7. (Where S i is an actual value of the area of the Voronoi polygon, m is an average value of measured values of the area of the Voronoi polygon, and n is the total number of Voronoi polygons) |