Incorporation of Nanofillers in Gel Polymer Electrolyte Systems Based on PMMA/PLA Doped with LiBOB: Correlation of Structural and Ionic Conduction Properties

Abstract

In this study, 2 wt.% to 12 wt.% of silica nanofiller (SiO2) compositions were incorporated into PMMA/PLA-20%LiBOB gel polymer electrolyte (GPE) systems and were characterized using Fourier Transform Infrared (FTIR) analysis, thermogravimetric analysis (TGA), electrical impedance spectroscopy (EIS) and transference number measurement (TNM). FTIR analysis showed slight changes in wavenumber shifting and intensity at the highlighted peaks, indicating molecular interactions have occurred in the present GPE. From the TGA analysis, the sample with 6 wt.% of SiO2 exhibited the least mass loss, confirming that it is the most thermally stable sample in this current study. The increasing ionic conductivity in samples up to 6 wt.% (2.19 × 10− 3 S cm− 1) after SiO2 was added might be due to the properties of SiO2 that act as a bridge to promote more ions complexation towards the polar polymeric chains. Through this study, it can be deduced that the sample with 6 wt.% of SiO2 has the most optimum behavior and it was chosen for TNM testing. Based on the TNM analysis, a high lithium-ion transference number (tLi+=0.79) was observed, indicating that this composition is practical for application in lithium-ion batteries.