Low Temperature Operated SOFCs Using Ceria Based Electrolyte

Ceria based electrolyte is one of candidates for low temperature SOFCs operated under 600 degrees C, since it has reasonably high ionic conductivity, and moderate material cost, in spite of the drawback, lower open circuit voltage. In this study, the effect of fabrication process of the cell on the cell performance was examined using micro tubular, anode-supported cell design. Two samples were prepared by co-sintering anode supported tube and electrolyte (Gd doped CeO2), using the sintering temperatures of 1260 and 1400 degrees C, respectively. The cell performance test showed that both samples had advantages depending up on the operating temperatures. The sample sintered at 1260 degrees C showed better cell performance operated at 450 degrees C, as high as 0.15 Wcm(-2), while the sample sintered at 1400 degrees C showed the power density of 0.49 Wcm(-2) at 550 degrees C, 1.4 times better than that of the sample sintered at 1260 degrees C. This behavior is resulted from the difference in the conductivity of the electrolyte and the microstructure of the anode, which were prepared form different sintering temperatures.