Separator having porous coating layer and electrochemical device having the same

Abstract

The present invention refers to a method for manufacturing a separator, comprising preparing first inorganic particles having an average diameter of 1 to 10 μm and coated with a coupling agent, and second inorganic particles having an average diameter of 50 to 500 nm and coated with a coupling agent on the surface thereof; mixing the first inorganic particles and the second inorganic particles together with a binder polymer and adding the resulting mixture to a solvent to obtain a slurry; and coating the slurry on at least one surface of a porous substrate.

What is claimed is: 
     
         1 . A method for manufacturing a separator, comprising
 preparing first inorganic particles having an average diameter of 1 to 10 μm and coated with a coupling agent, and second inorganic particles having an average diameter of 50 to 500 nm and coated with a coupling agent on the surface thereof;   mixing the first inorganic particles and the second inorganic particles together with a binder polymer and adding the resulting mixture to a solvent to obtain a slurry; and   coating the slurry on at least one surface of a porous substrate.   
     
     
         2 . The method for manufacturing a separator according to  claim 1 , wherein the slurry further comprises functional particles. 
     
     
         3 . The method for manufacturing a separator according to  claim 1 , wherein the weight ratio of the first inorganic particles:the second first inorganic particles ranges from 50:50 to 90:10. 
     
     
         4 . The method for manufacturing a separator according to  claim 1 , wherein the weight ratio of a mixture of the first inorganic particles and the second first inorganic particles:the binder polymer ranges from 80:20 to 90:10. 
     
     
         5 . The method for manufacturing a separator according to  claim 2 , wherein the functional particles are selected from a water scavenger, a Mn scavenger, an HF scavenger and a mixture thereof.