CORRELATION OF SELF-DIFFUSIVITY AND IONIC-CONDUCTIVITY IN GEL ELECTROLYTES ON BASIS OF OLIGO(ETHYLENE GLYCOL)(N)-DIMETHACRYLATE

The relation between the ionic conductivity and the charge carrier dif fusivity of an electrolyte is given by the Nernst-Einstein equation. H owever, this equation is in disagreement with data in the field of pol ymer electrolytes. We have measured the ionic conductivity of differen t liquid and gel electrolytes and the self-diffusivity of the plastici zer, the Li-containing, and the F-containing species by pulsed field g radient nuclear magnetic resonance spectroscopy (PFG-NMR). The results are discussed in terms of a modified Nernst-Einstein equation, consid ering that only charged ionic species contribute to the conductivity w hereas PFG-NMR measures the self-diffusivity of charged as well as non charged species. (C) 1998 Elsevier Science B.V. All rights reserved.