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A new phenomenological one‐dimensional model is formulated to simulate the typical degradation patterns observed in solid oxide fuel cell (SOFC) anodes due to coal syngas contaminants such as arsenic (As) and phosphorous (P). The model includes gas phase diffusion and surface diffusion within the anode and the adsorption reactions on the surface of the Ni‐YSZ‐based anode. Model parameters such as reaction rate constants for the adsorption reactions are obtained through indirect calibration to match the degradation rates reported in the literature for arsine (AsH3), phosphine (PH3), hydrogen sulfide (H2S), and hydrogen selenide (H2Se) under accelerated testing conditions. Results from the model demonstrate that the deposition of the impurity on the Ni catalyst starts near the fuel channel/anode interface and slowly moves toward the active anode/electrolyte interface as observed in the experiments. Parametric studies performed at different impurity concentrations and operating temperatures show that the coverage rate increases with increasing temperature and impurity concentration, as expected. The calibrated model was then used for prediction of the performance curves at different impurity concentrations and operating temperatures. Good agreement is obtained between the predicted results and the experimental data reported in the literature.

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Reference electrodes are frequently applied to isolate the performance of one electrode in a solid oxide fuel cell. However, reference electrode simulations raise doubt to the veracity of data collected using reference electrodes. The simulations predict that the reported performance for the one electrode will frequently contain performance of both electrodes. Nonetheless, recent reports persistently treat data so collected as ideally isolated. This work confirms the predictions of the reference electrode simulations on two SOFC designs, and provides a method of validating the data measured in the 3-electrode configuration. Validation is based on the assumption that a change in gas composition to one electrode does not affect the impedance of the other electrode at open circuit voltage. This assumption is supported by a full physics simulation of the SOFC. Three configurations of reference electrode and cell design are experimentally examined using various gas flows and two temperatures. Impedance data are subjected to deconvolution analysis and equivalent circuit fitting and approximate polarization resistances of the cathode and anode are determined. The results demonstrate that the utility of reference electrodes is limited and often wholly inappropriate. Reported impedances and single electrode polarization values must be scrutinized on this basis.