Dear colleagues,

Thirty years ago, there were great expectations for the hydrogen fuel cell economy, but, in the following decades, it has experienced cycles leading society from excessive expectations to substantial doses of disappointment. Recently, electrification infrastructures have been growing very fast, and the main global automotive manufacturers are investing in electric cars, including hybrids, battery electric, and fuel cell electric, and consumer interest in zero-emission vehicles has arisen exponentially. There has been a radical change in social perceptions of hydrogen technologies in a short period of time. A growing body of evidence suggests that hydrogen fuel cells are appearing again as an attractive solution to reduce carbon dioxide emissions and the latest improvements are pointing towards their economic viability. This technology may provide energy independence, security, and resilience, and foster the use of local resources and strengthen domestic economies. Fuel cells are well established in certain niches and are already in use and advancing positions in real-world applications such as industrial-scale backup power systems, mobile power for electric trains, buses, material handling systems, and heavy-duty transport trucks. Hydrogen vehicles and fuel cell home heating systems are commercially available in several countries.

On the other hand, portable solutions for highly demanding consumer electronic applications are still pending on new developments, especially for hydrogen fuel storage solutions. They should be capable of repeatedly turning off and on and should have turndown capabilities required to match the dynamic power needs of the devices. For widespread adoption, portable power fuel cell systems should minimize lifecycle environmental impact through the use of reusable fuel cartridges, recyclable components, and low-impact manufacturing techniques. In general, challenges around cost and performance still remain, and further improvements are required for hydrogen production and storage technologies to become truly competitive, although competitiveness with other low or zero-emission technologies seems to be now more realistic.

For this Special Issue, we invite papers on innovative developments, including new materials, novel technologies and applications, reviews, case studies, and analytical and assessment papers relevant for the development fuel storage for hydrogen fuel cell systems. Topics of interest for publication include, but are not limited to the following:

• Design and optimization of electrode materials, catalyst layers, electrolytes, and single cells for portable applications in PEMFC and SOFC technologies: application of novel nanostructures and advanced functional materials.
• Alternative fuels for storage. Advances in catalytic and electrocatalytic processes for hydrogen production (reforming of fuels, dehydrogenation of liquid organic hydrides, controlled hydrolysis of compounds, etc.).
• Development of portable power fuel cell systems.
• Advances in manufacturing processes for cost reduction.
• Novel portable applications and technology demonstrations: unmanned aerial vehicles, drones, portable electronics, radio control (RC) cars, boats, robot toys, emergency lights, military devices for communication, etc.
• Approaches in direct and indirect hydrogen fuel storage methods for portable devices.
• Original contributions covering life-cycle assessment (LCA) and sustainability of portable hydrogen fuel cell technologies, including their carbon footprint impact and socio-economic analyses.

Dr. Paloma Ferreira-Aparicio
Dr. Araceli Fuerte
Guest Editors

Manuscript Submission Information

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• portable fuel cell generator
• portable hydrogen
• solid oxide fuel cells
• SOFC
• proton exchange membrane fuel cells
• PEMFC
• micro-fuel cell power.