▎ 摘　　要

NOVELTY - Manufacturing secondary battery (10) separator (400) involves dissolving a water-soluble polymer binder in water to prepare an aqueous binder solution, dispersing particles in the solution, preparing a separator substrate (410). The slurry is applied on upper and lower surfaces of the substrate to form a slurry coating layer. The substrate includes a hydrophobic material. The slurry has a viscosity of 100-6000 cP. The binder has a molecular weight of 50000-5000000 g/mol. The weight of the water is 40-70 wt.%. The particles have a particle size of 100nm-10 mm. The coating layer has a thickness of 0.5-10 mm. USE - Method for manufacturing secondary battery separator used in portable electronic communication device such as mobile phone and notebook computer. Can also be used in wearable device, electric vehicle, and energy storage system (ESS). ADVANTAGE - The method provides a secondary battery separator having improved thermal stability and mechanical stability. The aqueous slurry coating layer has a porosity of 20-80% and a thickness of 0.5-10 m (preferably 0.6-1.5 m, especially 0.7-10 m). DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of secondary battery Secondary battery (10) Positive electrode (100) Negative electrode (200) Separator (400) Separator substrate (410)