Development and investigation of alkaline electrolyte based direct ammonia fuel cells

Abstract

In the present thesis study, alkaline electrolyte based direct ammonia fuel cells are developed, and their performances are evaluated through various parameters and efficiencies, such as open circuit voltages, polarization curves, peak power densities and energy and exergy efficiencies. The open circuit voltage and peak power density for the anion exchange membrane based direct ammonia single-cell fuel cell are observed to be 279 mV and 19.2 W/m2 respectively, and the energy and exergy efficiencies are evaluated to be 15.2% and 14.4% respectively. Furthermore, a molten alkaline electrolyte based fuel cell provides an open circuit voltage and peak power density of 520 mV and 2.1 W/m2 respectively. The energy and exergy efficiencies for this type of fuel cell are evaluated to be 24.9% and 23.4%. Lastly, a novel hybrid ammonia fuel cell and battery system is developed that provides an energy efficiency of 27.5% and an exergy efficiency of 27.5%.