A Controllable Thermal-Sensitivity Separator with Organic−Inorganic Hybrid Interlayer for High-Safety Lithium-Ion Batteries

A bifunctional organic–inorganic hybrid separator (PAN/EVA@SiO2/PAN, PESP) for lithium-ion batteries was successfully fabricated by a facile electrospinning approach. This PESP separator shows an appropriate shutdown behavior at 120 °C by incorporating a suitable amount of SiO2 into the EVA and can maintain dimensional integrity at 200 °C because of the high thermal stability of PAN as a supporting scaffold. Besides, the graphite/LiFePO4 full cell using the PESP separator exhibits enhanced rate performance as a consequence of the good electrolyte wettability of the separator compared to the traditional Celgard separator. These attractive characteristics make the PESP membrane act as a promising separator for next-generation high-safety batteries.