Fluoride scavengeable Sb2O3-functionalized poly(imide) separators for prolonged cycling of lithium-ion batteries.

Nanosize-controlled antimony oxides (Sb2O3) that can effectively scavenge fluoride species in a cell are incorporated into a PI separator to regulate its porous structure. The incorporation of the Sb2O3 layer onto the PI separator surface prevents the internal short circuit and efficiently removes fluoride species via chemical scavenging reactions, thereby resulting in stable cycling behaviors upon cycling.