The performance of a single-chamber solid oxide fuel cell (SOFC) was studied between 350 and 900°C in flowing mixtures of methane, ethane, propane, or liquefied petroleum gas and air with a fuellair volume ratio of one, where their oxidation proceeded safely without explosion. Among all tested electrode materials, Ni-Ce 0.8 Sm 0.2 O 1.9 cermet and Sm 0.5 Sr 0.5 CoO 3 oxide functioned best as the anode and cathode, respectively, in various gas mixtures. A cell constructed from a La 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 3 electrolyte with the two electrodes generated >900 mV in a methane-air mixture between 600 and 800°C and in an ethane-air mixture between 450 and 650°C. A small electrode reaction resistance resulted in increasing power density with decreasing electrolyte thickness. The peak power density at 450°C increased from 34 to 101 mW cm -2 with decreasing electrolyte thickness from 0.50 to 0.18 mm. The working mechanism of the single-chamber SOFC at different temperatures was also studied by measuring the catalytic activities of the two electrodes for partial oxidation of the hydrocarbons.