COMPOSITION FOR PREPARING SEPARATOR FOR ELECTROCHEMICAL DEVICE, PREPARATION METHOD OF SEPARATOR FOR ELECTROCHEMICAL DEVICE, AND ELECTROCHEMICAL DEVICE USING THE SAME

摘要

PURPOSE: A composition for manufacturing a separator is provided to remarkably improving high temperature stability and mechanical properties of a separator, thereby improving the lifetime and stability of an electrochemical device. CONSTITUTION: A composition for manufacturing a separator comprises polyethylene, a diluent, and polytetramethylene ether glycol. A manufacturing method of a separator comprises: a step of manufacturing the composition for manufacturing a separator; a step of cooling phase separation by cooling the composition for manufacturing the separator; and a step of obtaining a separator for forming pores by extracting polytetramethylene ether glycol into an extraction solvent from the composition at the crystallization temperature of the polyethylene or less.