Ion transport theory of nonaqueous electrolytes.: LiClO4 in γ-butyrolactone:: the quasi lattice approach

As a part of a study on the optimisation of the electrolyte for high-density energy lithium batteries, transport properties of concentrated LiClO4 solutions in gamma -butyrolactone (BL) have been investigated. The effect of the salt concentration (C) on the viscosity (n) of BL solutions has been discussed in term of the Jones-Dole equation. At concentrations higher than 0.2 M, the molar conductivity (Lambda) of LiClO4 solutions follow a C-1 (3) cube root law which is predicted by the quasi lattice model first introduced by Gosh. In this model, the: ions of the strong binary electrolyte are distributed in a lattice-like arrangement (fcc). The experimental value found for the slope of Lambda vs. C-1 (3) relation is in fair agreement with the calculated one. The effect of the temperature on the viscosity and the conductivity of electrolyte solutions have been examined. These two transport processes are well described by Arrhenius type laws from which the activation energies for the viscosity E-an and conductivity E-a Lambda are deduced. The variations of E-an and E-a Lambda with salt concentration are respectively dependent on C and C-4 (3) as predicted by the quasi lattice model. (C) 2001 Elsevier Science Ltd. All rights reserved.