Three-Dimensional Performance Simulation of SOFC Anodes Using FIB-Tomography Reconstructions

In this contribution a three-dimensional (3D) finite element method (FEM) model that enables the performance simulation of solid oxide fuel cell (SOFC) Ni/YSZ cermet anodes is presented. The 3D FEM anode model enables the spatially resolved simulation of the electrochemical processes at the triple phase boundary (TPB) and the intrinsic coupling with the ionic, electronic and gaseous transport in the complex three-phase microstructure. Experimental data obtained from measurements with patterned model anodes are used for a detailed description of the electro-oxidation kinetics at the TPB. This numerical approach is combined with 3D reconstructions gained by focused ion beam (FIB) tomography used as the model geometry. Hence, all critical microstructure parameters are intrinsically considered in the 3D anode model. Simulations for a reconstructed anode functional layer were conducted for a temperature range between 450°C and 950°C. The simulated performance showed a good agreement with experimental data of technical Ni/YSZ cermet anodes.