摘要 |
A separator with a heat resistant insulation layer includes a porous substrate layer and a heat resistant insulation layer formed on one surface or both surfaces of the porous substrate layer and containing inorganic particles and a binder. The ratio of tensile strength in MD direction×fracture strain in MD direction to the tensile strength in TD direction×fracture strain in RD direction is in a range from 0.3 to 20. A ratio of the unit mass of the heat resistant insulation layer to the unit mass of the porous substrate layer is in a range from 0.5 to 2.5. Accordingly, the separator with a heat resistant insulation layer can have improved resistance to an internal short-circuit (shorting resistance). |