Comparative study on the performance of a SDC-based SOFC fueled by ammonia and hydrogen

A nickel-based anode-supported solid oxide fuel cell (SOFC) was assembled with a 10 μm thick Ce0.8Sm0.2O2−δ (SDC) electrolyte and a Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) cathode. The cell performance was investigated with hydrogen and ammonia gas evaporated from liquefied ammonia as fuel. Fueled by hydrogen the maximum power densities were 1872, 1357, and 748 mW cm−2 at 650, 600, and 550 °C, respectively. While with ammonia as fuel, the cell showed the maximum power densities of 1190, 434, and 167 mW cm−2, correspondingly. The power densities lower than that predicted, particularly at the lower operating temperatures for ammonia fuel cell, compared to hydrogen fuel cell, could be attributed to actual lower temperature than thermocouple display due to endothermic reaction of ammonia decomposition as well as the rather larger inlet ammonia flow rate. The results demonstrated that the ammonia was a right convenient liquid fuel for SOFCs as long as it was keeping the decomposition completion of ammonia in the cell or before entering the cell.