SEPARATOR FOR NON-AQUEOUS SECONDARY BATTERY AND NON-AQUEOUS SECONDARY BATTERY

Provided is a separator for a non-aqueous secondary battery containing a porous substrate using a polyolefin porous film; and a heat-resistant porous layer that is provided only on one side of the porous substrate, and that contains a heat-resistant resin and a filler, in which a TD elastic modulus of the porous substrate is from 1.2 GPa to 5.0 GPa.