Distributed-charge transfer model analysis of SDC-based IT-SOFCs for the electrochemical oxidation of syngas and biogas

Aim of this work is the development of a distributed charge-transfer numeric model for intermediate temperature solid oxide fuel cells (IT-SOFCs) with composite electrodes. The model describes the leakage current inside a mixed ionic electronic conducting (MIEC) electrolyte. The reaction interface is extended along the whole length of the electrodes and a one-dimensional description of charge transfer phenomena is entailed. The profiles of the ionic and the electronic current density, as well as the profiles of the ionic and the electronic potentials are described along the whole length of the cell. The model is applied to analyze the experimental results of IT-SOFCs based on Samarium doped Ceria (SDC) electrolytes, Cu-Pd-CZ80 anodes and LSCF cathodes. Hydrogen electro-oxidation experiments are examined first, then the analysis is extended to the simulation of OCV data collected when feeding biogas mixtures to the anode.