Particle-based model for functional and diffusion layers of solid oxide cells electrodes

Abstract

A novel particle-based model is proposed to generate synthetic yet representative 3D microstructures of typical SOC electrodes. The model steps can be related to the real electrode manufacturing routes, classically via powders processing, making it a practical tool for electrodes design optimization. The representativeness of the synthetic microstructures is checked on several two-phase (LSCF, LSC) and three-phase (Ni-YSZ) electrodes reconstructed by synchrotron X-ray and FIB-SEM tomography. The validation shows a very good agreement between the real and synthetic media in terms of metric, topological and physical properties. Furthermore, the model is adapted to simulate the microstructure of a typical Ni-YSZ current collecting layer by taking into account a bimodal pore-size-distribution. In this objective, the macro-pores resulting from the burning-off of specific pore-formers are morphologically separated in the reconstruction from the micro-porosity network. Finally, the geometrical features of the macro-pores are meticulously characterized and successfully emulated by using parametric ellipsoids.