3D Effective Conductivity Modeling of Solid Oxide Fuel Cell Electrodes

摘要

The effective conductivity of a thick-film solid oxide fuel cell (SOFC) electrode is an important characteristic used to link the microstructure of the electrode to its performance. With the development of increasingly accurate three dimensional (3D) imaging methods of fuel cell microstructures by destructive (e.g. focused ion beam) and non-destructive (e.g. X-ray tomography) techniques, we are now capable of analyzing more effectively the relationship between microstructural characteristics and overall cell performance. A 3D resistance network model has been developed to determine the effective conductivity of a given SOFC electrode microstructure. This paper presents an overview of the functionality of the 3D resistance network model alongside a comparison of resistance data with analytical results from literature and commercial software packages. A given 3D SOFC anode microstructure reconstructed from imaging processes is initially discretized into voxels, typically 1/25th the size of a nickel particle, based on which a mixed resistance network is drawn. A potential difference is then applied to the network which yields by mathematical manipulation the corresponding current, finally allowing for the equivalent resistance of the entire structure to be determined.