A Simple Expression for the Tortuosity of Gas Transport Paths in Solid Oxide Fuel Cells’ Porous Electrodes

Based on the three-dimensional (3D) cube packing model, a simple expression for the tortuosity of gas transport paths in solid oxide fuel cells’ (SOFC) porous electrodes is developed. The proposed tortuosity expression reveals the dependence of the tortuosity on porosity, which is capable of providing results that are very consistent with the experimental data in the practical porosity range of SOFC. Furthermore, for the high porosity (>0.6), the proposed tortuosity expression is also accurate. This might be helpful for understanding the physical mechanism for the tortuosity of gas transport paths in electrodes and the optimization electrode microstructure for reducing the concentration polarization