Silver ion conducting nanocomposite polymer electrolytes: Ion transport and battery fabrication

Abstract

Ion transport characterization studies on a new Ag⁺ ion conducting (poly-ethylene oxide) PEO-based nanocomposite electrolytes (NCPEs): (1-x) [30PEO:70(0.75AgI:0.25AgCl)] + x SiO₂, where 0<x<20 wt.%, have ben reported. A novel hot-press/ solvent free technique has been used for the formation of the present NCPE films. Nano-size (~ 8 nm) SiO₂ particles have been dispersed as a second dispersoid in to the first phase host matrix: [30PEO:70(0.75AgI:0.25AgCl)], identified as the highest conducting polymer electrolyte composition. A conductivity enhancement of more two orders that of the pure polymer-electrolyte host could be achieved in the nano-composite polymer electrolyte composition: 95[30PEO:70(0.75AgI:0.25AgCl)] + 5SiO₂ (σ ~ 6.2 × 10^-5 S.cm^-1) and this has been referred to as optimum conducting composition (OCC). Polymer-salt/ nano-filler complexations have been explained with the help of XRD, DSC and TGA analysis. To explain the ion transport characterization various ionic transport parameters viz. conductivity (σ), ionic mobility (μ), mobile ion concentration (n), ionic transference number (t_ion) etc. have been determined at room temperature and the temperature dependent conductivity measurements have also been carried out to evaluate the activation energy (E_a). A new Ag⁺ ion conducting solid state polymer battery have been fabricated and studied the cell parameters at room temperature.