Experimental analysis of ammonia as input fuel for molten carbonate fuel cell

Hydrogen fuel cells can generate clean and efficient energy, and ammonia as a hydrogen carrier contains more hydrogen in its molecule than hydrogen itself. Utilizing green ammonia as fuel for fuel cells can reduce dependency on fossil fuels. However, there has been less study on the electrochemical performance of ammonia molten carbonate fuel cells (MCFCs). Hence, this paper sets up a single MCFC experimental bench to conduct research on direct ammonia molten carbonate fuel cells. The electrochemical performance of a direct ammonia MCFC is investigated in terms of key parameters such as temperature and the volume flow ratio of NH3/H2 entering the anode. Additionally, Scanning Electron Microscopy (SEM) is employed to study the electrodes of the MCFC. Experimental findings demonstrate that the direct ammonia MCFC performs optimally at 680 degrees C with a current density of 0.059 A/cm2 and an ammonia conversion rate up to 91.6%. When the mixture gas of NH3 and H2 is used as the cell fuel, the current density (0.057 A/cm2) and the conversion rate of NH3 (84.9%) are higher when the volume flow ratio of NH3/H2 is 9, indicating that the increase of H2 proportion in the mixed gas will affect the conversion of NH3. SEM image analysis of the MCFC electrodes post-experiments reveals that ammonia does not destruct the loose and porous structure of MCFC electrodes, affirming that NH3 can be directly used as the MCFC fuel.