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

Disclosed is an electrochemical device separator including a porous polymer substrate and an organic/inorganic composite porous coating layer formed on at least one side of the polymer substrate, wherein the organic/inorganic composite porous coating layer comprises particulate binder resins and first inorganic particles, the particulate binder polymers include hybrid polymer particles of a fluorine-based polymer and an acrylic-based polymer and acrylic-based polymer particles, the acrylic polymer particles have a particle size D50 “a” in a range of 1 to 7 μm, the first inorganic particles have a particle size D50 “b” in a range of 200 to 800 nm, a/b is 2 to 15, and the hybrid polymer particles have a particle size D50 smaller than that of the acrylic polymer particles.