Electrochemical studies on polymer electrolytes based on poly(methyl methacrylate)-grafted natural rubber for lithium polymer battery

MG30 is natural rubber grafted with 30% poly (methyl methacrylate). Gel polymer electrolytes containing MG30-LiCF3SO3-X (X=propylene carbonate, ethylene carbonate) are prepared by solution casting technique. The polymer-salt complexes were investigated using Fourier-transformed infrared. The ionic conductivity of the electrolytes are determined by the ac impedance studies over the temperature range of 303-383 K and is observed to obey the Vogel-Tamman-Fulcher (VTF) rule. The Li+ transference number obtained using the Bruce and Vincent method is <0.3. The Li/Li+ interface stability is established and the electrolytes were found to be able to withstand a voltage of more than 4.2 V.