SEPARATOR COMPRISING POROUS NON-WOVEN FABRIC BASE FILM CONSISTING OF CORE-SHEATH COMPOSITE FIBERS, AND ELECTROCHEMICAL DEVICE COMPRISING SAME

摘要

The present invention relates to a separator, and more particularly, to a separator comprising a porous non-woven fabric base film consisting of core-sheath composite fibers and an electrochemical device comprising the same. According to an embodiment of the present invention, a separator including a porous non-woven fabric base film and a porous coating layer is provided. The porous non-woven fabric base film comprises composite fibers having a sheath part surrounding a core part, wherein parts of or whole of the sheath part are combined to each other, the core part comprises heat type high molecules of which the melting point is 150 or higher, and the sheath part comprises high molecules of which the melting point is 50 lower than that of the heat type high molecules. The porous coating layer is coated in at least one among one or more surface of the porous non-woven fabric base film and the pores and contains mineral grains and binder high molecules that are arranged at part of or whole of the mineral grains to fixate and connect the mineral grains. The separator in the present invention has excellent tensile strength and, by the tensile strength, exhibits excellent shut-down function when structural faulty or overheating of the base film caused by thermal contraction occurs. Also, when batteries in which this excellent and stable separator is assembled are manufactured, defective batteries are less likely to be manufactured.