Modeling and evaluating of thermo-electro-chemo-mechanical behavior for pre-reformed methane-fueled solid oxide fuel cell

Catalyst deactivation and mechanical failure are the major obstacles to the commercial application of methane-fueled solid oxide fuel cells (SOFCs). While integrating SOFCs with methane pre-treating system is considered as an effective measure to improve its stability. Therefore, an integrated system of SOFCs and thermally self-sustained methane steam reformer (TS-MSR) is proposed in present work and a three-dimensional multi-physics model is developed to comprehensively evaluate its thermo-electro-chemo-mechanical behavior. The results show that the design of TS-MSR should be paid attention when conducting the integrated system to achieve the balance between cell performance and stability. An overdesigned TS-MSR would cause higher temperature, induce higher thermal stress and even break down the SOFCs. The corresponding maximum temperature reaches 1311 K and the resulting thermal stress reaches 669 MPa where the failure probability is close to 1. The mechanical failure is most likely to occur in the cathode porous electrode, despite the fact the highest stress exists in the electrolyte. This study makes up for the deficiency that previous literatures usually ignore the effect of pre-reformer design when conducting thermo-electro-chemo-mechanical analysis.