Numerical Assessment of SOFC Anode Polarization with Microstructure Evolution

A phase field method was introduced to simulate the microstructural evolution of nickel-yttria stabilized zirconia composite anode of solid oxide fuel cell in high temperature sintering based on three-dimensional microstructures reconstructed by focused ion beam-scanning-electron-microscopy technique. Nickel phase morphology and crystal structure evolutions and the change of nickel network percolation in operation were simulated simultaneously. In order to quantitatively study the correlation between anode microstructure change and the anode electrochemical performance degradation, the evolution of three-phase boundary density and nickel specific surface area were calculated. Corresponding degradation experiments have been conducted to compare with the simulation results. The experimental results showed good agreement to the simulation results.