CHARACTERISTICS OF 3-DIMENSIONAL ELECTRODES FOR A MOLTEN-CARBONATE FUEL-CELL ANODE

The characteristics of fluidized-bed and fixed-bed electrodes have been studied in a molten carbonate fuel cell anode of 42 mm i.d. and 500 mm height with an air/CO2/gold reference electrode in a half-cell at 923-1073 K. Nickel and nickel-coated alumina particles were employed as the working electrode. 80% H-2 and 20% CO2 fuel gas was fed into the working electrode at a velocity of 1.7-27 mm s-1. In the fixed-bed electrode, the diffusion polarization was predominant, whereas polarization was not under diffusion control with the fluidized-bed electrode. The ohmic resistance through contact between electrode particles and the current collector can be reduced by using a large current collector in a fixed-bed electrode, and electrode performance improves with incresing cell temperature.