Molten Carbonate Fuel Cell Research at ORNL. II. Theoretical and Experimental Transport Studies, Thermochemistry, and Electron Microscopy

摘要

Activities in the molten carbonate fuel cell program at ORNL during the period March 1977 to August 1977, funded by ERDA's Division of Conservation Research and Technology, are summarized. These activities include the extension of theoretical and modeling studies of mass transport in molten Li sub 2 CO sub 3 -K sub 2 CO sub 3 mixtures for the prediction of possible composition gradients. A parametric representation has been developed that incorporates the effects of current density, electrode separation, initial composition, effective Li/K mobility ratio and effective interdiffusion coefficient. Electrolysis experiments designed to test the model and simulate mass transport in an operating fuel cell are being carried out by analysis of emf-time relaxation curves measured after electrolysis. Direct analysis of composition profiles in electrolyte tiles is being developed by means of scanning electron microscopy with energy dispersive x-ray fluorescence. Differential scanning calorimetry has been applied to the thermochemistry of the carbonate electrolyte and lithium aluminate matrix. (ERA citation 03:024390)