Molten Carbonate Fuel Cell Program. Composition Gradients Induced by Current Flow in Li sub 2 CO sub 3 -K sub 2 CO sub 3 Mixtures. Progress Report, July 1-December 31, 1978

摘要

In a molten carbonate fuel cell current flow can cause gradients in the Li/K ratio of a LiKCO sub 3 electrolyte if the cation mobilities are, as in most binary molten salt mixtures, unequal. A one-dimensional model predicts 10 to 20 percent composition gradients from estimated values of mobility, activity and diffusivity, none of which is well known. Predictions from a similar model for a system of known properties have been confirmed experimentally by electrolysis-relaxation experiments. The model calculations for carbonates appear consistent with electrolysis-relaxation measurements on fuel cell tiles, but clearly indicate the need for additional specific physical property data, especially the transference number. This report is based on the material presented at the EPRI-DOE sponsored Molten Carbonate Fuel Cell Workshop, held at Oak Ridge National Lab., October 31-November 2, 1978. (ERA citation 05:008768)