A High Performance Direct Carbon Solid Oxide Fuel Cell Stack for Portable Applications

A direct carbon solid oxide fuel cell (DC-SOFC) stack was prepared with 3 tubular cells electrically connected in series. To increase carbon storage in the stack, the anode was fabricated outside the tubular cells so that carbon fuel can be loaded at the exterior of the stack, which is more spacious than the interior. The 3-cell-stack is operated directly with carbon as the fuel and oxygen in ambient air as the oxidant. With a total effective area of 10.2 cm2 and a 5% (w) Fe-loaded activated carbon fuel of 17 g, the stack reveals a peak power of 4.1 W at 800°C. The stack discharged at a constant current of 1.0 A for 19 h, giving a charge capacity of 19 A·h and an energy capacity of 31.6 W·h, which are much higher than those of a similar stack with anode on the inside and carbon loaded at the interior. The high capacity of our DC-SOFC opens up potential applications in portable devices.