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

Abstract 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 La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3−δ (LSCF)–GDC as the cathode. A single tubular cell with a diameter of approximately 1.8 mm and an effective electrode length of approximately 20 mm generated 150 mW cm −2 and 340 mW cm −2 at 500 °C and 550 °C, respectively, under the operation conditions of 0.7 V and humidified H 2 fuel flow. The cell exhibited good stability with a degradation rate of 0.25%/100 h under operation conditions of 200 mA and 0.75 V.