Preparation and properties of gel‐filled PVDF separators for lithium ion cells

Polyether gel‐filled poly(vinylidene fluoride) separators (GF‐PVDF separators) were prepared by means of thermal crosslinking of poly(ethylene glycol) methyl ether acrylate (PEGMEA) and poly(ethylene glycol) diacrylate (PEGDA) as gel constituents. The intrinsic properties of GF‐PVDF and their corresponding gel polymer electrolyte (GPE) were characterized by SEM, DSC, and electrochemical methods. It was found a relatively better GPE could be got when the filled polyether content no more than 60 wt % and its ion conductivity could reach 1.3 × 10^?3 S cm^?1. The GPE is compatible with anode and cathode of lithium ion battery at high voltage and its electrochemical window is 4.6 V (vs. Li/Li⁺). The coulombic efficiency could reach 94% after 100 cycles for the cells using such GPE. The results reveal that the composite polymer electrolyte qualifies as a potential application in lithium cells. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44473.