Curable polymeric binder–ceramic composite-coated superior heat-resistant polyethylene separator for lithium ion batteries

Abstract

A thermally stable modified PE separator prepared as a necessary component of lithium-ion batteries (LIBs) for electric vehicles (EVs) by coating a composite of curable copolyester (cPET) and Al₂O₃ onto the surface of a bare polyethylene (PE) separator. After curing, the composite-coated separator demonstrated excellent dimensional stability at high temperature. Even when exposed at 170 °C, the composite-coated separator shrank only 13% and the unit cells containing the cPET–PE separator had a cycle life close to that of cells made from the bare PE separator.