Patent ID: 9564624
Date: 2017-02-07
CPC Classifications: C08J,C08L,H01M,Y02E,Y02P

Claim:
1. A microporous composite film having a coating layer with a thickness of 3 to 8 μm and a porosity of 25 to 60% formed on at least one surface of a microporous polyolefin film, the coating layer simultaneously including a high thermostable polymer resin having a melting temperature or glass transition temperature of 170° C. to 500° C. and inorganic particles having a porosity of 40 to 80%, wherein the microporous composite film has the following properties: 1) an area shrinkage (170° C., 1 hr) is 10% or less; 2) a tensile modulus in each of a machine direction and a transverse direction at 130° C. is 0.5 MPa to 7.0 MPa; 3) a ratio between permeability of the microporous composite film (CCS 4) a permeability of the microporous composite film is 450 sec or less; and 5) a ratio between an average pore diameter of the microporous polyolefin film (S