Numerical investigation of the effect of functional layer thickness on solid oxide fuel cell performance

ABSTRACT

In this 3D numerical study, the effects of cathode and anode functional layer thicknesses on the performance of solid oxide fuel cells under different operating parameters are analysed and elucidated. The performance of the model is evaluated using direct ammonia and an equivalent amount of hydrogen fuel with functional layers ranging from 0 to 50 μm. The findings unveiled that the cathode functional layer has a stronger influence on cell performance than the anode functional layer. The parametric analysis also showed that the effect of temperature gradually weakened with the increase of the cathode functional layer which is the exact opposite of what anode functional layers do. This gives more promising result for the cathode functional layer than the anode functional layer, especially for hydrogen-powered cells. However, the anode functional layer works best when green ammonia is supplied directly to the solid oxide fuel cell. In this regard, the 10 μm functional layers of the anode and cathode layers achieved the highest possible power density using ammonia and hydrogen fuels under similar operating conditions. This suggests that the anode layer has outstanding performance than the cathode counterparts for ammonia-fuelled cells and the layers of the cathode have better performance for hydrogen-fuelled cells. It is also observed that the performance of the cell is decreasing while the thickness of the functional layer is increasing particularly after 10 μm. The study also confirmed that solid oxide fuel cells with functional layers have outstanding performance over corresponding cells without functional layers. Thus, the finding of this study concluded that the functional layer thickness is strongly dependent on the types of fuel and electrodes used in the cells.

KEYWORDS:

• Numerical modeling
• functional layers
• ammonia
• solid oxide fuel cell

Acknowledgments

I am enthusiastic to acknowledge Bahir Dar Energy Center of Bahir Dar Institute of Technology, Bahir Dar University for its continuous support.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The datasets for this numerical investigation are not available as all operational and fitting parameters, as well as the software used for numerical analysis, are supplied in the manuscript.

Additional information

Notes on contributors

Molla Asmare

Dr. Molla Asmare, an assistant professor of Energy Systems Engineering, at Bahir Dar Energy Center, Bahir Dar Institute of Technology, Bahir Dar University, Ethiopia, has a first degree in Chemistry an MSc in Sustainable Energy Engineering and a P.hD In Energy Systems Engineering. He has several published articles in renewable energy and environmental issues. He won the second prize in applied science and technology at the international students science congress of Turkey. He also worked as Energy experts at bureau level. His research interest is fuel cell, advanced energy storage and conversion, E-Mobility, hydrogen storage, bioenergy, solar energy, combustion and modelling.