Towards the Design-Led Optimization of Solid Oxide Fuel Cell Electrodes

Abstract

A one-dimensional numerical model of a nickel-infiltrated gadolinium-doped ceria (Ni-GDC) electrode has been developed to investigate the effects of electrode microstructure on performance. Electrode microstructural information was obtained with focused-ion beam tomography and microstructural parameters were quantified. These have been used to estimate the effective transport coefficients and the electrochemical reaction rate in the electrode. GDC was considered as a mixed ionic and electronic conductor and hence the electrochemical reaction was assumed to occur on the GDC-pore contact surface, i.e. double-phase boundaries (DPBs). Sensitivity analysis was conducted to investigate the effect of electrode microstructure on both transport properties and electrochemical activity. The developed model offers a basis to understand the electrode-microstructure relationships and to further optimize the electrode microstructures.