Rare Earth Oxide Dispersed PEO‐Based Solid Polymer Electrolytes: EIS ANALYSIS (ICSEM 2025)

Significant research has been initiated toward getting alternative energy sources to mitigate long‐term dependence on conventional natural resources and enhance the efficiency of existing technologies in recent past. Among the different materials examined, the solid polymer electrolytes (SPEs) were found as one of the important materials for energy storage devices. This is because SPE offers very good flexibility and superior safety characteristics. The development of SPE exhibiting good ionic conductivity for potential applications of energy storage and conversion systems. Crystallinity can be reduced by incorporating inert oxide fillers, and consequently, can enhance the ionic conductivity too. In this work, we report the influence of lanthanum oxide (La 2 O 3 ) dispersion on the properties of poly(ethylene oxide)‐based polymer electrolytes. Solid polymer electrolyte films comprising PEO:NaI with varying weight percentages of La 2 O 3 were fabricated using the solution casting technique. Electrochemical impedance spectroscopy (EIS) was employed to evaluate the electrical properties of the prepared films. The ionic conductivity of the samples was determined through EIS measurements, and additional parameters, including the dielectric constant, electrical modulus, charge carrier concentration, and mobility, were derived from the EIS data. The maximum conductivity of 2.70 × 10 −03 S/cm was obtained for 5wt% dispersoid. The paper presents a detailed analysis of these parameters and discusses their interrelations to elucidate the effect of La 2 O 3 dispersion on the electrochemical performance of the PEO‐based polymer electrolyte system.