Starch/PVA nanocomposite solid polymer electrolyte films have been prepared by adding fumed silica nanoparticles in biodegradable polymer blend composed of Starch and PVA using Glutaraldehyde as crosslinker and glycerol as plasticizer. FTIR studies of the polymer electrolyte films confirm the complexation of fumed nano silica with the polymer matrix and reveal the structural changes occurring due to different content of nano fumed silica. It could be affirmed that the CAOASi bonds formed by nano fumed silica with Starch or PVA play a crucial role in enhancing the ionic conductivity. Correlating the results of FTIR and dielectric measurement the maximum conductivity observed for the nano composite polymer electrolyte film with 3 wt% silica could most possibly be ascribed to the formation of three dimensional networks due to interaction
of nano fumed silica with Starch or PVA. The three dimensional networks so formed pave the way for ion conduction paths. In addition, the increment in the number of charge carriers occurring due to the nano fumed silica is another prominent factor that augments the ionic conductivity. The decline in conductivity observed at 4 wt% of silica is attributed to the blockage of the conducting pathways due to agglomeration of fumed silica nanoparticles. Electric modulus studies ascertain the ions as the dominant charge carriers in the system. Absence of electrode polarization is also confirmed by the modulus stud ies. Temperature dependence of the electric modulus at selected frequencies affirms the increase in ionic conductivity at high temperature. Scaling of the electric modulus shows the temperature dependence of relaxation mechanism in the sample with maximum ionic conductivity at room temperature. In the light of the results obtained from the electrical measurements it will not be fallacious to expect that the nano composite solid polymer electrolyte obtained from biodegradable polymers composed of Starch and PVA with glycerol and glutaraldehyde as additives and nano fumed silica as filler has the potential to be attested as an efficient system for Lithium ion conduction. The present study predicts that a methodical and systematic approach to tailor the system can yield still higher values of ionic conductivity at ambient conditions.