Peak Power Optimization of Solid Oxide Fuel Cells with Particle Size and Porosity Grading

Abstract

Solid oxide fuel cells (SOFCs) are blessed with high efficiency, the capability of using a variety of hydrocarbon fuels, and high impurity tolerance. Functionally graded electrodes have previously been investigated to improve SOFCs performance with controlled microstructure. However, little investigation has been focused on the cell-level optimization of power output for nonlinearly graded electrode microstructures. In this work, a multiscale electrode polarization model of SOFCs has been expanded and developed to a cell-level model. The cell-level SOFCs model has been utilized to disclose the complex relationship among the transport phenomena, which include the transports of electron, ion and gas molecules through the electrode and the electrochemical reaction at the triple phase boundaries. The work advances the understanding of the cell performance with graded microstructures. The performance of functionally graded electrodes has been analyzed to understand the effects of tailored electrode microstructures on cell power output.