Experimental and numerical investigation of direct ammonia solid oxide fuel cells with the implementation of ammonia decomposition source terms in a 3D finite volume-based model

Ammonia and fuel cells have become more popular in the past few years. This is directly associated with the prevailing industrial trend toward reducing emissions. Ammonia is a fuel that can be utilized in solid oxide fuel cells (SOFCs). Nevertheless, ammonia-fueled solid oxide fuel cells (DA-SOFCs) are sensitive to the degradation during operation. This study aims to determine the causes of such incidents as using experimental and numerical methods. Investigation of cells with various thicknesses of anode support layers revealed that the cells fracture during long-term operation under a load of 0.125 A cm- 2 . The OpenFuelCell (OFC) model developed by the author for the DA-SOFC analysis showed a high temperature gradient (up to 70 degrees C) in the microstructure. It was found that increasing the amount of ammonia supplied to the cell from 33.3 ml min- 1 to 50 ml min- 1 while maintaining the same fuel utilization increases the difference in temperature by 55 %. Subsequently, it was shown that the presence of ammonia in the anode functional layer (ASL) of the cell is associated with a decrease in DA-SOFC efficiency. The investigation identifies potential areas for improving DA-SOFCs from both the operational and manufacturing point of view and offers a tool for investigating these areas.