In situ mineralized Ca3(PO4)2 inorganic coating modified polyethylene separator for high-performance lithium-ion batteries

•Flower-like calcium phosphate coating is successfully formed on the surface of modified PE separator.•The obtained composite separator exhibits stronger affinity to electrolyte and absorbs more liquid electrolyte.•CaP@PE separator possess an improved ionic conductivity (0.52 mS cm−1) and lithium-ion transference number (0.36).•Cell assembled with CaP@PE separator exhibits excellent cycle performance and rate performance.