Silicone modified polypropylene separator for high temperature lithium ion battery applications

The poor thermal stability of polyolefin separator greatly limits the output performance and safety performance of a lithium ion battery at high temperature. Herein, we report a novel silicone grafted polyolefin separator prepared by a simple solution process and its lithium ion battery performance. Despite its low coating thickness, the grafted silicone coating significantly improved the thermal stability of polyolefin separator. In addition, the silicone grafted separator shows enhanced electrolyte affinity. Due to these favorable features, the novel separator exhibits enhanced battery performance at a high temperature of 80 °C. Our results suggest that the silicone grafted separator could be potentially used in practical battery applications.