A comparative study of different carbon fuels in an electrolyte-supported hybrid direct carbon fuel cell

An electrolyte-supported hybrid direct carbon fuel cell (DCFC) was used to evaluate the performance of different carbon fuels in this study. The direct carbon fuel cell consists of a samarium doped ceria (SDC) electrolyte, a Ni/SDC anode and a Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3-δ cathode. Three types of carbon (graphite, coal and activated carbon) and three particle sizes of activated carbon (70, 250 and 500μm) were investigated at 650-750°C. The electrochemical reactivity of these three types of carbon fuels was in the order of activated carbon>German creek coal>graphite. Sulphur in German creek coal has poisoning effect on Ni catalyst resulting in lower power density of the fuel cells. The activated carbon (250μm) fuelled hybrid DCFC achieved a peak power density of 158.3mWcm^-2 at 750°C along with the maximum current density of 561.5mAcm^-2. However, the stability of the hybrid DCFC is poor and need to be improved at the present.