Enhancing performance of planar structure single unit 800 °C O2-SOFC at atmospheric pressure: A numerical modeling approach for electric power production

Solid oxide fuel cells generate electricity with high electrical efficiency and flexibility in fuel use without emitting pollutants, such as carbon dioxide, nitrogen oxides, sulfur oxides and particulates. Nevertheless, they still face several obstacles and challenges that pose problems and questions driving researchers to find solutions. Numerical simulation is a key tool for integrating various physical fields, including charge dynamics, electrochemical pathways, chemical species kinetics, fluid flow, and energy transformations. The Butler-Volmer equation, in its various forms and approximations, is the most widely used equation for relating electrochemical pathways to current density in solid oxide fuel cell modeling. The main objective of this research is to model and simulate a high-temperature solid oxide fuel cell at atmospheric pressure, in order to test the effect of changing some properties values on the electrical power density produced. The results obtained revealed several techniques for enhancing the fuel cell performance, by improving the physical behaviors appropriate to each property on the corresponding side. It was found that fuel cell performance improves with increasing values of porosity rate, exchange current density, and pressure drop, and with decreasing both cell length and electrolyte thickness. Furthermore, since the electrolyte's conductivity class is oxygen ion carrier, the effect of parameters at the cathode side was more significant compared to the anode side. The results of this research are consistent with well-documented theories, and it is usable for developing other numerical models.