In this study, we investigated the improvement in electrical conductivity of a polymer with the addition of dissolved lithium hexafluorophosphate (LiPF₆) in an ether based solvent, butyl glycidyl ether (BGE). Thin film samples were fabricated by adding LiPF₆ (up to 1 wt%) to poly (methyl-methacrylate) (PMMA). Film with 0.75% LiPF₆ showed the highest improvement of electrical conductivity by three orders of magnitude. Both FTIR spectra and X-ray diffraction studies confirmed the formation of BGE–LiPF₆ complex. Differential Scanning Calorimetry was used to characterize the PMMA/LiPF₆ specimens further. Dielectric experiments revealed the existence of multiple composition dependent relaxation processes: β (high frequency) and β (low frequency) relaxation processes. The results suggest that electrical conductivity could be improved without influencing the domain polymer and the composite materials, including their processability. This work suggests that the conductivity of nanocomposites with various solid conductive fillers may be sufficiently enhanced in combination with this ion conduction approach involving a “liquid conductive filler.” Since BGE is compatible with epoxy molecules, further study is expected to lead to an effective solution to conductive epoxy composites in their wide field of applications including aircraft and multifunctional energy sources such as structural batteries.