Micro-modelling of IT-SOFC electrodes manufactured through electrospinning

Infiltrated electrodes for intermediate temperature-solid oxide fuel cells (IT-SOFCs) are currently the subject of intense research. Focusing on electrodes with a fibrous microstructure typically obtained through the electrospinning technique, we analyze the role of infiltrations from a modelling point of view. The model includes the evaluation of i) charge transfer reaction occurring at the dopant particles and, possibly, at the electrode/electrolyte interface; ii) electron and/or oxygen-ion conduction along the fiber, and iii) additional charge conduction along the dopant nano-particles, if percolating occurs throughout the electrode structure. The model is applied to doped anodes and cathodes, considering infiltration loadings below and above the percolation threshold. The model allows evaluating the overall reciprocal electrode resistance 1/Rp and the electrochemically active thickness (EAT). Simulation results demonstrate good agreement with literature experimental data.