Performance of a Porous Electrolyte in Single-Chamber SOFCs

A cell which consists of a porous 18 p.m thick Y-doped ZrO2 (YSZ) electrolyte (23 - 3 vol % open porosity) on a NiO-YSZ anode substrate and a cathode using (La, Sr)(Co, Fe)O3 has been investigated in the single-chamber configuration. The cell performance and catalytic activity of the anode was measured in a flowing air-methane gas mixture with various flow rates. The results showed that the open-circuit voltage and the power density increased as the gas flow rate increased. The cell generated an open-circuit voltage of about 0.78 V, which was only about 0.1 V lower than that observed with dense electrolyte specimens. A maximum power density of 660 mW cm-2 (0.44 V) was obtained at set temperature = 606DGC (cell temperature = 744DGC) in the flow rate of 900 cm 3 min, where the current efficiency was about 5% determined from fuel consumption.