Effects of Reduced Firing Temperature on Anode-Supported Solid Oxide Fuel Cells

Abstract

Anode-supported solid oxide fuel cells (SOFCs) with yttria-stabilized zirconia (YSZ) electrolytes were co-sintered at a temperature as low as 1250°C, lower than the usual 1400°C, by using 1 mol% Fe2O3 sintering aid. The effect of sintering temperature on cell electrochemical performance was investigated for cells with two different composite cathodes: (La0.8Sr0.2)0.98MnO3−δ (LSM) – YSZ or La0.6Sr0.4Fe0.8Co0.2O3 (LSCF) – Gd-doped Ceria (GDC). For the latter case, the electrolyte included a 1.4-μm-thick GDC layer that was co-sintered with the YSZ electrolyte and Ni-YSZ anode. Open-circuit voltages were near theoretical values for all cells. The LSM-cathode cell maximum power densities increased with decreasing sintering temperature, due to a decrease in anode polarization resistance. Cells with LSCF cathodes had substantially lower cathode polarization resistance and higher power density than the LSM cells. Energy-dispersive X-ray analysis did not detect GDC/YSZ interdiffusion or zirconate formation in the LSCF/GDC/YSZ region.