ELECTROCHEMICAL DEVICE SEPARATOR INCLUDING POROUS ORGANIC/INORGANIC COMPOSITE COATING LAYER AND ELECTROCHEMICAL DEVICE INCLUDING SAME

An electrochemical device separator including a porous polymer substrate and a porous organic/inorganic composite coating layer on at least one surface of the porous polymer substrate. The porous organic/inorganic composite coating layer includes particulate binder polymers, a non-particulate acrylic-containing polymer, and first inorganic particles. The particulate binder polymers include hybrid polymer particles including a fluorine-containing polymer and an acrylic-containing polymer, and acrylic-containing polymer particles. The acrylic-containing polymer particles have a particle size D50 (a) in a range of 1 μm to 7 μm, the first inorganic particles have a particle size D50 (b) in a range of 200 nm to 800 nm, a/b is in a range of 2 to 15, and hybrid polymer particles have a particle size D50 less than 250 nm.