Patent ID: 9713793
Date: 2017-07-25
CPC Classifications: B01D,H01M,Y02E

Claim:
1. A method for producing a microporous membrane, the microporous membrane comprising a plurality of pores and walls, the walls defining the pores, said method comprising: mixing a polymer with a pore forming agent and a filler material to form a pre-formed mixture; and solidifying said polymer in the presence of said pore forming agent and said filler material to form said microporous membrane where said filler material is incorporated into said microporous membrane and bound with said polymer; wherein said microporous membrane comprising at least 2 parts of said filler material to 3 parts of said polymer by volume; said microporous membrane comprising pores having a diameter of 0.1 to 1 micron; said polymer having a surface free energy lower than said pore forming agent; said polymer wetting said filler material; and the ratio of said wall thickness to particle size of said filler material being in a range of 1:1 to 20:1.