SECONDARY BATTERY

Provided is a very safe secondary battery that can prevent the occurrence of battery abnormalities even when the internal battery temperature increases due to, for example, overcharging. A separator 70 in this secondary battery has a laminated structure that is provided with at least two porous layers 76A, 72, 76B, wherein one of these layers forms a porous electroconductive layer 72 in which an electroconductive material 74 is dispersed in the porous layer.