Paper

Research and development of NH3-fueled solid-state fuel cell systems

Ammonia is a prospective carbon-free fuel source for fuel cell systems due to low production cost, ease in liquefaction at ambient temperatures, and high energy density. Furthermore, hydrogen and nitrogen originating from ammonia fuel are expected to have little negative effect on fuel cell performance, while hydrocarbon fuels draws some severe problems at electrodes, such as CO poisoning or carbon deposition in low- and high-temperature fuel cells, respectively. Several technologies can be considered for the ammonia utilization in fuel cell systems. For the utilization of ammonia fuel, we aim to develop a system combined with ammonia decomposition reactor and solid-state…

Paper

A Green Ammonia Economy

Ammonia has a high volumetric hydrogen density of 107.3 kg H2 per cubic meter, because it is easily liquefied by compression below 0.86 MPa at 20° C. The vapor pressure of liquefied ammonia is similar to propane. Moreover it has a high gravimetric hydrogen density of 17.8 mass% compared with the solid state hydrogen storage materials. It is noteworthy that ammonia can be synthesized from hydrogen in large scale manufacturing by Haber–Bosch process at 400-600° C and 20-40 MPa. Therefore, liquid ammonia is one of the most promising methods for storing and transporting hydrogen. CO2 free hydrogen (ammonia) will be…