Strategic Overview on Fuel Cell-Based Systems for Mobility and Electrolytic Cells for Hydrogen Production

Given the global effort to embrace research actions and technology enhancement for the energy transition, innovative sustainable systems are needed both for energy production and for those sectors that are responsible for high pollution and CO2emissions. In this context, electrolytic cells and fuel cells, in their variety and flexibility, are energy systems characterized by high efficiency and important performance, guaranteeing a sustainable solution for future energy systems and for the circular economy. The scope of this paper is therefore to present the state of the art of such systems. An overview of the electrolyzers for hydrogen production is presented, by detailing the level of applications for their different technologies, from low-temperature units to high-temperature units, the fuel flexibility, the electrolysis and co-electrolysis mode, and the potential coupling with renewable sources. Fuel cell-based systems are also presented, and their application in the mobility sector is investigated, by considering road transport, with light-duty and heavy-duty applications, and marine transport. A comparison with conventional technologies will be also presented, providing some hints on the potential applications of electrolytic cells and fuel cell systems, given their important contribution to the sustainable and circular economy.