Steady-state modeling of transport and reaction in sofc composite cathodes with distributed porosity

A steady-state mathematical model of charge and mass transport and electrochemical reaction in porous composite LSM/YSZ cathodes for solid oxide fuel cell application is presented. The model, based on local mass and charge balances, describes the domain as a continuum, characterizing kinetics as well as mass and charge transport using effective properties, related to cathode microstructure by percolation theory. The distribution of morphological properties, as experimentally observed on scanning electron microscope images, is taken into account. This feature allows the model to reproduce the dependence of electrode thickness and partial oxygen pressure on polarization resistance in the range 600-850\ub0C