New microporous polyethylene, polypropylene and polyvinylidene fluoride films as separators for lithium-ion batteries have been elaborated. The materials were obtained in the process based on polymer melt extrusion. Investigations of the batteries in the mode of charge-discharge cycles were carried out. It is shown that these porous materials match or exceed performance characteristics of industrially produced separators "Celgard 2400". It was found the use of polyethylene separators permits to prevent an emergency situation caused by an increase in temperature during battery operation.