Polymers complexed with lithium salts are promising for use as solid electrolytes in solid-state lithium batteries. However, the key issue is the ionic conductivity and the process of enhancing it for better performance. Polyethylene glycol-based solid polymer electrolytes complexed with lithium salts are being investigated to explore their suitability in battery applications. In the present work, we report the investigations carried out on PEG-based solid polymer electrolyte complexed with lithium tri-fluoromethanesulfonate (LiCF₃SO₃). The ionic conductivity profile as a function of salt content is studied. The effect of the addition of inert nanofiller SiO₂ is also investigated to understand the mechanism of enhancement of ionic conductivity. The preparation of the nanocomposite solid polymer electrolytes and characterization by other techniques like powder XRD, IR spectroscopy, thermal measurements and conductivity profile obtained from AC impedance measurements are discussed to get an insight into the mechanism of ion transport and the influence of the addition of nanofiller.

Keywords: Solid Polymer Electrolyte; Ionic Conductivity; Nanocomposite