Preparation and Electrochemical Characterization of Magnesium Gel Electrolytes based on Crosslinked Poly(tetrahydrofuran)

Abstract A crosslinked poly(tetrahydrofuran) (c-PTHF) was synthesized as a novel polymer matrix for gel polymer electrolyte (GPE) swelled with Mg(TFSI)2/triglyme solution to develop Mg-ion battery. Two GPE based on c-PTHF with different crosslinking structure and crosslinker ratio were obtained as free-standing membranes with excellent heat resistance. From the CV measurement, the Pt/GPE/AZ31 cell clearly showed Mg redox reaction, and the values of current densities in reduction/oxidation peaks and the Coulombic efficiency were larger than those of the triglyme electrolyte solution. This may be due to the changes in the solvation structure of Mg2+ ions by the presence of crosslinking structures in the network framework.