Because the transport segment makes up about one-third of all CO2 emissions in the European Union (> 1,000 MILL ton), its decarbonization represents a key element in achieving the energy transition. Fuel Cells and Hydrogen (FCH), outperforming batteries in all relevant indicators, is the most promising solution for decarbonizing trucks, buses, ships, trains, large cars, with commercial vehicles being considered the early adopters. By 2030 this new industry has the potential to generate a €130 bn market only in the European Union. The market-entry goal is to fit 5kg H2 in a gasoline equivalent tank (80 kg/90 l). However, state-of-the-art technology for H2 storage on-board, based on compression at 700bar, is still disappointing in terms of volumetric density (25 gH2/lsys), preventing a widespread penetration of FCEVs.