Polymer gel electrolytes based on poly(vinylidene fluoride co-hexafluoropropylene), and containing layered nanoparticles such as fluorohectorite were investigated by pulsed gradient spin-echo nuclear magnetic resonance (NMR), as well as line shape and relaxation studies. Diffusion coefficients of Li+ ions, anions, and electrolyte solvent were measured by Li-7, F-19, and H-1 NMR, respectively. All results indicate heterogeneous ionic environments in the nanocomposite materials. (C) 2003 Elsevier Science Ltd. All rights reserved.