Technologies for the Storage of Hydrogen Part 1: Hydrogen Storage in the Narrower Sense

Abstract

Storage of hydrogen in an efficient and dense manner is still a challenge. In addition to the conventional technologies of compression and liquefaction, there are different approaches trying to enhance the storage density by bonding hydrogen to another substance. Physisorption and chemisorption to organic as well as inorganic carriers are options. Although many of these technologies have not yet gone beyond the technological readiness of lab scale tests, there are a few that have already reached advanced technological levels. The first part of this two‐part review discusses storage technics with recovery of elemental hydrogen.

Materials Challenges and Opportunities for Energy Generation, Conversion, Delivery, and Storage (Applied Energy Tri-Laboratory Consortium Workshop Report)

“…For hydrogen liquefaction, significant losses of hydrogen resulting from heat transfer and large energy requirements severely impede practical application, despite the advantages of higher volumetric density [6]. The density of liquefied hydrogen is much higher compared to compressed hydrogen, but it has the second lowest critical temperature at 33 K, so cryogenic-compressed approaches store hydrogen as a supercritical fluid, which enjoys higher storage density [12] and storage capacity (~5x greater). Hydrogen liquefaction is energy intensive and time consuming, with lost energy content as high as 40%, whereas with compressed gas, it is only 10% [3].…”

“…Hydrogen liquefaction requires a large capital investment [12,7]. High costs are, in part, due to the need for specialized storage, driven by the demanding requirements imposed by liquid hydrogen.…”

“…Implementation of hydride compounds as hydrogen storage media has been hindered by either unfavorable kinetic barriers or the stable thermodynamics of the compounds, which can result in poor reversibility. The kinetic barriers principally result from the fact that hydrogen has to diffuse through the metal hydride solid for both hydrogen uptake and release [12]. Consequently, the binding and release kinetics are unacceptably slow, and the hydrogen adsorption coefficient is not favorable [9].…”

“…The thermodynamic impediment, to some extent, can be ameliorated by incorporating a catalyst in the metal hydride to reduce desorption temperatures [12]. This approach has also been combined with attempts to improve storage capacity using doping and nanoconfinement approaches.…”

Hydrate Dissociation Using Microwaves, Radio Frequency, Ultrasonic Radiation, and Plasma Techniques

“…About 1 m 3 of natural gas hydrate can produce about 170 m 3 of natural gas at STP (standard conditions) [1]. Due to this feature, gas hydrates are researched for a number of diverse areas of application like energy storage [2,[5][6][7], seawater desalination [7][8][9], CO 2 capture [10][11][12][13], and other separation applications [14,15]. Information regarding fundamentals of gas hydrates is well explained in Sloan and Koh [1] and also compiled by several researchers for specific applications [16][17][18][19][20][21][22][23].…”