A Review of Heat Transfer Issues in Hydrogen Storage Technologies

Significant heat transfer issues associated with four alternative hydrogen storage methods are identified and discussed, with particular emphasis on technologies for vehicle applications. For compressed hydrogen storage, efficient heat transfer during compression and intercooling decreases compression work. In addition, enhanced heat transfer inside the tank during the fueling process can minimize additional compression work. For liquid hydrogen storage, improved thermal insulation of cryogenic tanks can significantly reduce energy loss caused by liquid boil-off. For storage systems using metal hydrides, enhanced heat transfer is essential because of the low effective thermal conductivity of particle beds. Enhanced heat transfer is also necessary to ensure that both hydriding and dehydriding processes achieve completion and to prevent hydride bed meltdown. For hydrogen storage in the form of chemical hydrides, innovative vehicle cooling design will be needed to enable their acceptance.