Effect of ceramic fillers on polyethylene glycol-based solid polymer electrolytes for solid-state magnesium batteries

Composite polymer electrolyte (CPE) materials are very attractive for components of batteries and optoelectronic devices. Polyethylene glycol–magnesium nitrate polymer electrolytes and their composites were prepared by using addition of different weight percentage of titanium dioxide (TiO₂) and cerium oxide ceramic fillers. Several experimental techniques, such as composition-dependence conductivity, temperature-dependence conductivity, and transport number measurements, have been employed to characterize these CPEs. The magnitude of conductivity increased with increase in the concentration of the ceramic fillers and temperature. The highest ionic conductivity achieved was 1.06 × 10⁻⁴ S/cm for the sample prepared with 10 wt% of TiO₂ at room temperature. The charge transport in the present CPEs was obtained using Wagner’s polarization technique, which demonstrated that the charge transport was mainly due to ions. Using these polymer electrolytes, solid-state electrochemical cells were fabricated and their discharge profiles were studied under a constant load of 100 kΩ.