A porous separator including a porous base film; and a coating layer, the coating layer being on a surface of the porous base film and including a polyvinylidene fluoride homopolymer, a polyvinylidene fluoride-hexafluoropropylene copolymer, and inorganic particles, wherein the separator exhibits a thermal shrinkage of about 30% or less in a machine direction (MD) or in a transverse direction (TD), as measured after leaving the separator at 150° C. for 1 hour, a peel strength of about 50 gf/cm2 or more between the coating layer and the base film, and an adhesive strength of about 20 gf/cm2 or more between the coating layer and electrodes of a battery.