High Performance Low Cost Co-Fired Solid Oxide Fuel Cells

Abstract

Anode-supported planar SOFCs were fabricated by a single step co-firing process. The cells comprised of Ni+yttria-stabilized zirconia (YSZ) anode, YSZ electrolyte, (La,Ca)MnO3 (LCM)+YSZ cathode active layer, and an LCM cathode current collector. The fabrication process involved tape casting of the anode, screen printing of the electrolyte and the cathode, and single step co-firing between 1300-1330{degree sign}C. Cells were tested between 700-800oC with humidified hydrogen and air. Modeling of cell- test results showed that most of the polarization losses were due to ohmic losses associated with the electrodes, activation polarization loss in the cathode, and concentration polarization loss in the anode. The ohmic loss was lowered by improving electrical contact, activation polarization was reduced by improving microstructure of the cathode active layer and the anode concentration polarization loss was lowered by increasing anode porosity. With all these improvements maximum power density of 1.5W/cm2 was achieved at 800oC with humidified H2(g) and air.