Micro-tubular solid oxide fuel cells and stacks

The properties and performance of micro-tubular solid oxide fuel cells are compared and the differentiating factors discussed. The best recorded power density for a single cell in the literature to date is 1.1 W cm−2, with anode microstructure and current collection technique emerging as two key factors influencing electrical performance. The use of hydrocarbon fuels instead of pure hydrogen and methods for reducing the resultant carbon deposition are briefly discussed. Performance on thermal and reduction–oxidation (RedOx) cycling is also a critical issue for cell durability. Combining these individual cells into stacks is necessary to obtain useful power outputs. As such, issues of fluid and heat transfer within such stacks become critical, and computational modelling can therefore be a useful design tool. Experimentally tested stacks and stack models are discussed and the findings summarised. New results for a simple stack manufactured at the University of Birmingham are also given.