Synthesis and characterization of PEO/PVDF polymer blend electrolytes doped with LiFePo₄ nanofiller and epoxidized natural rubber plasticizer

This research focuses on the preparation and characterization of polymer blend electrolytes based on polyethylene oxide (PEO) and polyvinylidene fluoride (PVDF), incorporating LiFePO4 as a nanofiller and epoxidized natural rubber as a plasticizer. The incorporation of LiFePO4 aims to enhance the electrochemical performance of the polymer blend by improving ionic conductivity and mechanical stability. The polymer blends were prepared using a solution-casting technique, where varying concentrations of LiFePO4 were introduced into the PEO/PVDF matrix. The XRD reveals the degree of crystallinity and the effect of LiFePO4 on the polymer structure. The undoped sample shows distinct crystalline peaks corresponding to the PEO and PVDF phases. A reduction in intensity is observed as the doping level increases, which indicates a reduction in crystallinity due to the disruption caused by the LiFePO4 particles. For the TGA/DTA graph, the undoped polymer blend (PEO75/PVDF25) shows a characteristic decomposition at (400–600°C), (5% of LiFePO4) curve, which shows early decomposition than other doped samples. The increased LiFePO4 content acts as a thermal barrier at higher concentrations, delaying the degradation process. The results indicate that the inclusion of LiFePO4 significantly influences the thermal properties of the PEO/PVDF blend electrolytes, making them promising candidates for use in high-performance lithium-ion batteries.