Operation of Ni-YSZ anode supported solid oxide fuel cell on different simulated syngas, this symposium

Ni-YSZ anode supported solid oxide fuel cells (ASCs) were tested under various simulated syngas. There was no voltage degradation of the cell operated on 41%H2-7%CH4-6%CO-11%CO2-35%H2O fuel condition for nearly 450 hours. However, the high vapor content reduced the open circuit voltage (OCV) and discharge voltage. The cells run steadily with most dry syngas until the simulated reforming temperature reduced to 500oC and steam to carbon ratio (S/C) reduced to 3. The corresponding composition of this syngas was 49%H2-24%CH4-8CO-14CO2-5%H2O. In this case, the voltage dropped quickly and the cell failed within 5 hours. The microstructure analysis showed that the failed cell had a carbon deposit layer of approximately 10 µm thickness close to the anode surface. The results indicated that carbon deposited quickly on Ni surface when there was no adequate carbon dioxide or vapor to avoid methane cracking