Insight of super-capacitive properties of flexible gel polymer electrolyte containing butyl imidazole ionic liquids with different anions based on PVDF-HFP

Abstract

Abstract Capacitors based on ionic liquid gel polymer electrolytes (GPEs) have received wide attention as an environmentally friendly energy source due to their good specific capacitance, good cycling capacity, and stability. Herein, flexible gel polymer electrolyte (GPE) films were prepared and applied using three butyl imidazole ionic liquids containing different anions as additives based on polyvinylidene fluoride hexafluoropropylene (PVDF-HFP). The structural and mechanical properties of GPE films have been characterized by SEM, XRD, FTIR, TGA, stress-strain, and DFT calculations, and their ionic conductivity has been tested by stainless steel methods. The assembled symmetric supercapacitor underwent testing via cyclic voltammetry, electrochemical impedance, and constant current charge-discharge methods. The objective was to assess the impact of various gel electrolytes utilized in the experiment. This work is useful to further verify the influence of the anionic component of ionic liquids on the physical and chemical properties of gel electrolytes and to prepare more excellent solid electrolytes for supercapacitors.