A General Mechanistic Model of Solid Oxide Fuel Cells

Introduction In recent years, increasing attention has been paid to application of fuel cell technology in both the automo- tive and power industries. Compared to conventional energy conversion technologies, fuel cells promise power generation with high e…

A General Mechanistic Model of Solid Oxide Fuel Cells

A comprehensive model considering all forms of polarization was developed. The model considers the intricate interdependency among the electrode microstructure, the transport phenomena, and the elec-trochemical processes. The active three-phase boundary surface was expressed as a function of electrode microstructure parameters (porosity, coordination number, contact angle, etc.). The exchange current densi-ties used in the simulation were obtained by fitting a general formulation to the polarization curves proposed as a function of cell temperature and oxygen partial pressure. A validation study shows good agreement with published experimental data. Distributions of overpotentials, gas component partial pressures, and elec-tronic/ionic current densities have been calculated. The effects of a porous electrode structure and of vari-ous operation conditions on cell performance were also predicted. The mechanistic model proposed can be used to interpret experimental observations and optimize cell performance by incorporating reliable experi-mental data.