DETERMINATION OF CONTACT-ANGLE IN POROUS MOLTEN-CARBONATE FUEL-CELL ELECTRODES

A method of capillary rise (gravimetrically measured) has been investi gated for determination of the electrolyte contact angle in porous ele ctrodes for the molten-carbonate fuel cell. The experiments were condu cted on LiCoO2 electrodes in air, at different temperatures (555 to 74 0 degrees C), to monitor the influence of the temperature an the conta ct angle. The results indicate that the contact angle decreases with i ncreasing temperature. The results obtained were of good reproducibili ty, and the method shows promise as a useful tool in characterization of wetting phenomena in porous fuel-cell electrodes, making it possibl e to study electrodes as manufactured, and under electrochemical condi tions. The wetting-in was characterized also by post-test measurements , and it was found that the wetting-in front (i.e., from no electrolyt e to fully flooded), extends over several millimeters.