METHOD FOR MANUFACTURING A HEAT-RESISTANT AND HIGH-STRENGTH ULTRAFINE FIBROUS SEPARATION LAYER

Provided is an ultrafine fibrous porous separator with heat resistance and high-strength and a manufacturing method thereof, which enables mass-production of a heat-resistant and high-strength ultrafine fibrous separator by using an air-electrospinning (AES) method, and to a secondary battery using the same. The method of manufacturing a heat-resistant and high-strength ultrafine fibrous porous separator includes the steps of: air-electrospinning a mixed solution of 50 to 70wt% of a heat-resistant polymer material and 30 to 50wt% of a swelling polymer material, to thereby form a porous web of a heat-resistant ultrafine fiber in which the heat-resistant polymer material and the swelling polymer material are consolidated in an ultrafine fibrous form; performing drying to control a solvent and moisture that remain on the surface of the porous web; and performing thermal compression on the dried porous web at a temperature of between 170°C and 210°C so as to obtain the separator.