Highly porous lithium-ion conducting solvent-free poly(vinylidene fluoride-co-hexafluoropropylene)/poly(ethyl methacrylate) based polymer blend electrolytes for Li battery applications

摘要

Plasticised polymer blend electrolytes based on poly(vinylidenefluoride-co-hexafluoropropylene) (PVdF-co-HFP) and poly(ethyl methacrylate) (PEMA) were prepared for different lithium salts LiX (X = ClO_4, CF_3SO_3, BF_4 and N[CF_3SO_2]_2) using facile solution casting. To confirm the structures and complexations of the electrolyte films, the prepared electrolytes were subjected to XRD and FTIR analysis. TG-DTA was used to ascertain the thermal stability of the electrolytes, and the porous nature of the electrolytes was identified using scanning electron microscopy via ion-hopping conduction. AC impedance analysis was performed for all the electrolyte samples at various temperatures from 303 to 363 K. The results suggest that among the various lithium salts, LiN[CF_3SO_2]_2-based electrolytes exhibited the highest ionic conductivity (0.918 × 10~(-3) S cm~(-1)). The temperature dependence of the ionic conductivity also complies with the VTF relation.