Electrochemical characterizations of microtubular solid oxide fuel cells under a long-term testing at intermediate temperature operation

▶ Urgent publication is justified due to the rapid pace of development in the fabrication and application of solid oxide fuel cells (SOFCs). We have demonstrated long-term testing of microtubular SOFCs at intermediate temperature operations. The small-scale SOFCs supported by a microtubular NiO–GDC anode, which were developed in this study, generated very high power density of 150mWcm−2 and 340mWcm−2 at 500°C and 550°C, respectively, under the operation conditions of 0.7V. The cell exhibited good stability with a degradation rate of 0.25%/100h under operation conditions of 200mA and 0.75V. We report the long-term stability of a microtubular solid oxide fuel cell (SOFC) operable at ∼500°C. The SOFC consists of NiO–Gd doped ceria (GDC) as the anode as well as the tubular support, GDC as an electrolyte and La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF)–GDC as the cathode. A single tubular cell with a diameter of approximately 1.8mm and an effective electrode length of approximately 20mm generated 150mWcm−2 and 340mWcm−2 at 500°C and 550°C, respectively, under the operation conditions of 0.7V and humidified H2 fuel flow. The cell exhibited good stability with a degradation rate of 0.25%/100h under operation conditions of 200mA and 0.75V.