Non-aqueous proton conducting polymer gel electrolytes

A new family of non-aqueous proton conducting polymer gel electrolytes containing different weak acids namely aromatic carboxylic acids have been prepared by using polyvinylidenefluoride (PVdF) and polyvinylidene fluoride-co-hexafluoropropylene (PVdF-HFP) as the gelling polymers. These gel electrolytes possess high value of conductivity in the range of 10(-3) to 10(-4) S/cm at room temperature, which has been found to depend upon the dissociation constant of the acid used. PVdF and PVdF-HFP provide good dimensional stability to these gel electrolytes and the addition of polymer has also been found to result in an increase in conductivity, i.e. sigma (gel) > sigma (liquid) which suggests that the polymer does not play a passive role but also affects the conduction process. From F-FIR studies it has been observed that the polymer enhances the dissociation of acid in these gel electrolytes resulting in an increase in carrier concentration. (C) 2004 Elsevier Ltd. All rights reserved.