SEPARATOR FOR LITHIUM ION SECONDARY BATTERY AND METHOD FOR MANUFACTURING THE SAME

摘要

PURPOSE: A separator for a lithium secondary battery has an interconnected porous network connected to each other and has excellent thermal stability and electrolyte-wettability while having a uniform porous structure. CONSTITUTION: In a separator (100), a porous polymer having an interconnected porous network connected by an etching pores-deriving material (20) with an average particle diameter of 0.001-10 um, is introduced to a porous unwoven fabric (12) with pores (40) with average particle diameter of 0.001-100 um. A manufacturing method of the separator comprises a step of providing the porous unwoven fabric; a step of preparing a coating solution by dispersing and mixing the pores-deriving material and a polymer in a solvent to prepare a coating solution; a step of coating the porous unwoven fabric with the coating solution; a step of removing the pores-deriving material from the coated porous unwoven fabric by an etchant; and a step of drying the porous unwoven fabric in which the pores-removing material is removed. [Reference numerals] (AA) Etching