Overview of hydrogen storage options

The physical and chemical properties of hydrogen impose technical boundary conditions on standard methods of storing H2 in pure form, such as a pressurised gas or cryoliquid. Table 9.1 lists the physical properties of H2, in comparison with methane and n-heptane, which were chosen as representatives of natural gas and gasoline, respectively. 

As an alternative, liquefied hydrogen (LH2) with a density of 70.8 kg/m3 (compared with 39 kg/m3 for H2 at 700 bar) is particularly attractive for attaining higher storage densities. The hydrogen has to be cooled down to 21K for liquefaction which, 

1 The gravimetric energy density of a pressure vessel is very much dependent on the material of the container, which in the case of carbon fibres accounts for around 60% of total storage-system costs. 

2 Current tank costs are still in the range of 2500-3000/kg hydrogen ( 75-90/kWh). Costs of gasoline tanks are around 

In practice, two basic bonding mechanisms are considered for hydrogen storage in solid-state materials  

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