FUNCTIONAL SEPARATOR, MANUFACTURING METHOD THEREFOR, AND LITHIUM SECONDARY BATTERY COMPRISING SAME

The present invention discloses a functional separator capable of improving the capacity and lifetime of a battery by coating a material capable of reducing lithium polysulfide on a separator surface in order to resolve the problems caused by leaching of lithium polysulfide, a preparation method thereof and a lithium secondary battery comprising the same. The functional separator comprises a base separator; a conductive carbon layer located on the surface of the base separator; and a metal oxide formed on at least one of the interior and the surface of the conductive carbon layer.