Complexes formed between lithium salts and low molecular weight (0.5 kg mol −1) poly(ethylene glycol) have been investigated by differential scanning calorimetry, 7Li nuclear magnetic resonance (NMR), and complex impedance measurements. 7Li NMR linewidths and hence ionic mobilities are strongly influenced by polymer segmental motion above the glass transition. Strong cation—anion interactions in LiBF 4 complexes are evidenced by substantial 7Li 19F dipolar coupling. Ionic conductivity results are similar to those reported for widely studied poly(ethylene oxide) complexes, in that broad conductivity vs salt concentration maxima are found. Finally, addition of up to 30 wt% of the inert ceramic powder γ-LiAlO 2, while improving the mechanical properties of the samples, is found to have a negligible effect on ionic conductivity.