Meniscus behavior of metals and oxides in molten carbonate under oxidant and reducing atmospheres .1. Contact angle and electrolyte displacement

The wetting of metals and oxides bg molten carbonate is an important factor affecting the performance of a molten carbonate fuel cell (MCFC). The distribution oi the electrolyte among electrodes and matrix in the MCFC is dominated by the pore characteristics and wetting properties of these components. However, data on wetting, especially under load (current passage), are Limited. In this study, the behavior of the meniscus at a metal is used to obtain information on wetting and electrochemical reactions. Meniscus height and current were measured under varioius atmopsheres. The contact angle was calculated from the meniscus height. The electrolyte distribution in the MCFC was estimated using contact angles thus obtained in oxidant and reducing atmospheres. The results suggest that upon applicatioin of load the electrolyte moves from the anode to the cathode and that capillary effects can worsen the performance of a cell, especially if it is in an unbalanced state of electrolyte filling.