Anode- Versus Cathode-Supported Solid Oxide Fuel Cell: Effect of Cell Design on the Stack Performance

This paper investigates the effect of cell design on solid oxide fuel cells (SOFC) stack performance. Based on 3-dimensional numerical simulations, it is found that the performance of stack is strongly dependent on cell design. The average current density of the anode-supported SOFC (ASC) stack is only 5580 A m(-2), a reduction of 20.7% from the cathode-supported SOFC (CSC) stack of 7033 A m(-2). This can be explained that compared with CSC stack, thin cathode in ASC stack leads to the smaller effective reaction zone and the larger cathode ohmic losses. The discrepancy between the ASC stack and the CSC stack are examined by varying rib width, contact resistance and pitch width. The results show conclusively that with the optimal rib width, the performance of the CSC stack is much superior to that of the ASC stack for any practical contact resistance and pitch width. The analyses provided in this paper assist in understanding the effect of cell design on cell performance in the stack level and playing the full potential of the stack by optimizing the cell design.