COMPOSITE SEPARATOR AND ELECTROCHEMICAL DEVICE INCLUDING THE SAME

Composite separators, methods for manufacturing the composite separators, and electrochemical devices including the composite separators are disclosed. In an embodiment, a composite separator includes a porous substrate, and a ceramic layer disposed on at least one surface of the substrate and including inorganic particles and a binder, wherein the binder includes polyacrylamide and carboxymethyl cellulose having a weight-average molecular weight of at least 180,000 g/mol and a degree of substitution in a range of 0.6 to 1.2, the polyacrylamide and carboxymethyl cellulose being included at a weight ratio of 60 to 90:40 to 10. The composite separator may exhibit excellent mechanical and thermal stability and excellent ion conduction properties.