Abstract: A novel gel polymer electrolyte (GPE) based on noepentyl glycol diacrylate (NPGDA) and poly(vinyli-dene fluofide-co-hexafluoropropylenen) (PVDF-HFP) was prepared by a thermal polymerization method. GPE with a stable interpenetrating polymer network (IPN) structure was used to assemble polymer lithium-ion batteries. The influence of PVDF-HFP/NPGDA mass ratios on the characteristics of GPE was studied by scanning electron microscopy, linear sweep voltammetry and electrochemical impedance spectroscopy. The results show that PVDF-HFP/NPGDA mass ratio greatly affects the performances of GPE, such as surface morphology and ionic conductivity. When the mass ratio between PVDF-HFP and NPGDA is 1:1, GPE boasts a high ionic conductivity of 6.99×10^-3 S•cm^-1 and an electrochemical stability window of 4.8 V(vs Li⁺/Li) at 25 ℃. The polymer lithium-ion batteries based on GPE also present excellent performances, such as high rate capability and discharge voltage plateau, good temperature reliability, and excellent cycling.

Key words: Gel polymer electrolyte, Noepentyl glycol diacrylate, Interpenetrating polymer network, Thermal polymerization, Polymer lithium-ion batteries