Hydrogen Storage

Storage is a vital factor in the commercialisation of fuel cells as a safe, efficient and energy dense way of storing hydrogen will greatly improve the viability of fuel cell technology, particularly for automotive applications. Hydrogen can be stored in any state; as a solid, a liquid or a gas.

More information about hydrogen storage can be found in this document from the International Energy Agency.

StateStorage Mechanism and supply mechanismAdvantagesDisadvantages
GasPressurised carbon fibre composite gas tank up to 700 barCommercially availableEnergy required for compression
Energy from fossil fuels usually used to produce hydrogen
Tanks are bulky and must be cylindrical
Safety concerns
Costly tanks
LiquidCryogenic tank at -253°CCommercially available
Excellent gravimetric and volumetric hydrogen capacity at low pressures
30-40% energy loss to cool to cryogenic temperatures
1%/day losses from boil off
Safety concerns
Costly tanks
SolidChemical hydrides heated to <100°C to decompose and release hydrogenExcellent gravimetric and volumetric hydrogen capacity
Safe, easy to handle
In the early development stages
Energy required for off-board regeneration
Harmful by-products must be removed from the impure hydrogen gas stream