Preparation and electrochemical properties of porous composite polymeric membranes

The porous composite polymeric membranes supported with Celgard 2300 films were prepared by phase-inversion method. The pore formation mechanisms of membranes during the preparation processes with dry and wet methods were investigated. Compared with Celgard 2300, the membranes exhibit higher PC uptake and sustain: the membrane made with wet method shows 246% PC uptake. The PC leakage was 9% after 14 days. The good pore diameter can prevent solution leakage. Conductivity of the membrane made with wet method was found to be 1.34×l0^-3 S·cm^-1 by AC impedance spectroscopy measurement. The batteries assembled with the membranes having better mechanics were tested and initial charge-discharge efficiency is up to 86%.