The enhancement of lithium ion dissociation in polyelectrolyte gels on the addition of ceramic nano-fillers

Nano-particle oxide fillers including TiO₂, SiO₂ and Al₂O₃ have previously been shown to have a significant affect on the properties of both polymer and polymer gel electrolytes. In some cases, conductivity increases of one order of magnitude have been reported in crystalline PEO–base complexes. In this work, we report the effects of TiO₂ and SiO₂ on a poly(Li-AMPS)-based gel polyelectrolyte. Impedance spectroscopy and pfg-NMR spectroscopy indicates an increase in the number of available charge carriers with the addition of filler. An ideal amount of ceramic filler has been identified, with additional filler only saturating the system and reducing the conductivity below that of the pristine polyelectrolyte system. SEM micrographs suggest a model whereby the filler interacts readily with the sulfonate group; the surface area of the filler being an important factor.