Enhanced ionic conductivity and electrochemical capacity of lithium ion battery based on PVDF-HFP/HDPE membrane

•PVDF-HFP/HDPE membrane with excellent ionic conductivity was successfully prepared via NIPS.•The novel PVDF-HFP/HDPE membrane has ionic conductivity of 2.97 mS cm−1 at 25 °C.•The LiCoO2/Li cells assembled with PVDF-HFP/HDPE membrane show good C-rate and cycling performance.

Poly(vinylidene fluoride-co-hexafluoropropylene)/high density polyethylene (PVDF-HFP/HDPE) membrane with enhanced ionic conductivity and electrochemical capacity for lithium ion battery application has been successfully prepared by non-solvent induced phase separation (NIPS) technique. HDPE particles with size smaller than 250 nm is achieved via optimized inverse emulsion polymerization method. Results indicate that the novel PVDF-HFP/HDPE membrane has ion conductivity of 2.97 mS cm−1 at 25 °C, higher than that 1.92 mS cm−1 of pristine PVDF-HFP membrane. Additionally, the LiCoO2/Li cells assembled with PVDF-HFP/HDPE membrane show good C-rate and cycling performance which is parallel to the commercial PP membrane.