Improvement of the internal reforming of metal-supported SOFC at low temperatures

Automotive Solid oxide fuel cells (SOFCs) require improvements in mechanical robustness, power generation at low temperatures, and system compactness. To address these issues, we attempt to improve the internal reformation of metal-supported SOFCs (MS-SOFCs) via catalyst infiltration. After introducing nickel/gadolinium-doped ceria (Ni/GDC) nanoparticles, power densities of 1.16 Wcm−2 with hydrogen (3%H2O) and 0.85 Wcm−2 with methane (Steam-to-Carbon ratio, S/C = 1.0) are obtained at 600 °C, 0.7 V. This is the highest performance achieved in previous studies on MS-SOFCs. Internal reforming with various hydrocarbon is also demonstrated. In particular 0.64 Wcm−2 at 600 °C, 0.7 V is obtained when the fuel is iso-octane. We develop a numerical model to separately analyze reforming and electrochemical reaction. Catalyst infiltration dramatically increases the number of active sites for steam reforming. In addition, ruthenium/gadolinium-doped ceria (Ru/GDC) should be suitable as a catalyst metal at low temperatures because of the lower activation energy of steam reforming.