Correlation Between Structural and Ionic Transport Properties of Lithium-ion Hybrid Gel Polymer Electrolytes Based PMMA-PLA

Abstract

In this work, the investigation on hybrid gel polymer electrolytes (HGPEs) comprising polymethyl methacrylate (PMMA)-polylactic acid (PLA) incorporate with LiTFSI were carried out. The HGPEs samples were characterized for their structural, thermal and ionic conduction properties via FTIR, XRD, DSC, and EIS. FTIR analysis show the indication of the interaction between PMMA-PLA hybrid polymer and LiTFSI with the appearance of peak and changes in peak shifting at the coordinating site from polymer blend. The DSC analysis shows that the glass transition temperature (Tg) of HGPEs was decreased as the LiTFSI content increases, suggesting that the HGPEs system has good thermal stability. The ionic conductivity was calculated based on the Cole-Cole plot and the incorporation of LiTFSI with 20 wt. % into hybrid polymer matrixes revealed the maximum ionic conductivity of 1.02 х 10-3 S cm-1 at room temperature as the amorphous phase increases. The dissociation of ions and transport properties of the PMMA-PLA-LiTFSI systems was determined via dielectric response approach and it was found that number density (ɳ), mobility (μ), and diffusion coefficient (D) of mobile ions follows ionic conductivity trend.