Investigations on charcoal as fuel for a refillable scandia-stabilised zirconia electrolyte-based tubular carbon fuel cell

A carbon fuel cell (CFC) is an emerging technology for conversion of solid carbonaceous material into electricity at high theoretical efficiencies (100 %). As carbonaceous material like coal will remain an important energy source for the next few decades, the development of technology that can use it more efficiently is critical to reduce emissions. For practical operation of a CFC, a continual supply or consecutive refuelling of solid carbon fuel is required. Here, we investigated the electrochemical performance and durability of a CFC using a scandia-zirconia tubular electrolyte with Ce0.9Gd0.1O2–Ag electrodes with activated charcoal fuel. We demonstrated that CFCs can be operated in a batch-type process with refuelling and utilisation of fuel. Peak power densities up to 280 mW cm−2 were obtained without major materials degradation. We expect that advances to engineering of fuel delivery will improve the long-term stability and performance of the cells.