Preparation and performance of p(OPal-MMA)/PVDF blend polymer membrane via phase-inversion process for lithium-ion batteries

Poly (methyl methacrylate) (PMMA) based gel electrolyte has excellent chemical stability and low interfacial resistance but its mechanical strength is poor. In this study, organic palygorskite modified PMMA (p(OPal-MMA)/poly(vinylidene fluoride)) (PVDF) blend based electrolyte membrane was prepared via phase inversion casting technique. The physical and electrochemical properties of the blend membrane were investigated by XRD, SEM, tensile test and electrochemistry workstation. The results showed that PVDF can significantly improve the mechanical strength. The crystal phase of PVDF disappeared after blending. The porosity and ionic conductivity of the p(OPal-MMA)/PVDF membrane was 57.73% and 4.93 x 10(-3) S/cm respectively. The electrochemical stability window of Li/gel B-PVDF electrolyte/SS cell was stable up to 4.7 V (vs. Li+ /Li), and the cell of Li/gel B-PVDF 43% electrolyte/LiFePO4 exhibited good cycling performance and the Coulombic efficiency was maintained above 98.5% during all the cycling process.