Physically-based modelling of the microstructure-performance correlation in SOFC anodes

The performance and durability of solid oxide fuel cells (SOFCs) are strictly related to the microstructure of the electrodes. The optimization of the electrode design can be addressed with physically-based models, capable to correlate the microstructural properties to the electrochemical performance. However, before suggesting optimization strategies, models must be carefully validated by using ad hoc experimental data. This contribution focuses on the validation of a physically-based model for SOFC composite anodes. The model is used to reproduce the experimental impedance spectra in different operating conditions, enabling the fitting of the unknown parameters of the model (Figure 1). The sensitivity of fitted parameters is discussed and their values are compared with independent sources in order to assess their soundness. The capability of the model to correlate the electrode microstructure to electrochemical performance is corroborated by analysing samples prepared with different fabrication processes or degraded in different conditions, with microstructural information obtained through 3D tomography. The study offers an opportunity to discuss about the best strategies for model validation comprising the choice of the optimal techniques and conditions that provide the best information, the verification of model assumptions and how to deal with experimental uncertainties.