MICROPOROUS POLYETHYLENE FILM WITH THERMALLY STABLE HYBRID-COMPOSITE LAYERS

摘要

Provided is a microporous organic/ inorganic composite coated layer comprising a heat resistant resin and inorganic particles, formed on at least one side of microporous polyethylene. The microporous polyethylene composite film is characterized by sufficient permeability and heat resistance at the same time, of which the permeability (Gurley) of overall composite film including a coated layer is not more than 300 sec; shrinkage after 150°C for 1 hour is 0~3% in both MD/TD directions; maximum shrinkage in TMA is not more than 3%, and TMA meldown temperature is 145-200 °C. The microporous polyethylene composite film formed by means of the coated layer possesses stability at high temperature as well as excellent permeability, thereby ensuring reliability and efficiency of a battery at the same time. A separator which conforms to high power/high capacity can be provided thereby.