A reinforced ceramic-coated separator by overall-covered modification of electron-insulated polypyrrole for the safe performance of lithium-ion batteries

Abstract

The safety of lithium-ion batteries (LIBs) is a serious and challenging problem that threatens the applications of large-scale energy storage as well as the daily usage of mobile devices. In this work, we developed a rational design of reinforced ceramic-coated separator by modifying the ceramic-coated separator with an overall-covered layer of electron-insulated polypyrrole throughout the entire separator. As a result, the modified separator shows an improved thermal stability without visible shrinkage at 200 °C, has a better electrolyte wettability and a higher Li⁺ transference number of 0.56. With these advantages, cells assembled with the modified separators show better safety performance and an improved rate capability.