Hydrogen storage materials and their development

Xingguo Li

The State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and molecule; Advanced Materials and Nanotechnology, College of Engineering, China

It has become increasingly clear that hydrogen as an energy carrier is ‘in’ and carbonaceous fuels are ‘out’. Hydrogen storage becomes an important technology for hydrogen energy application and hydrogen storage materials have received a lot of interests as one of the important key materials for future clean hydrogen energy systems.

The metal hydrides (or hydrogen storage alloys) are most important hydrogen storage materials, which have AB₅, AB₂, AB₃, A₂B₇, A₆B₂₃, AB, A₂B types. Among them, Lanthanum nickel-based hydride has been widely researched and used because of its excellent properties at room temperature. However, its hydrogen storage capacity is only 1.4 mass %, almost the smallest one among the metal hydrides. For this reason, Mg based, Ti-V based and Zr based alloys are developed and the hydrogen content of 2.7 -3.0 mass % is reached. In this talk, general properties and research movement of these hydrogen storage alloys will be firstly introduced.

As fuel cell technology develops, hydrogen energy application in mobile becomes more available and hydrogen-storage materials with higher hydrogen storage capacity are expected. The target of hydrogen storage capacity is 6 mass% H₂ in 2010 and 9 mass% H₂ in 2020. In order to reach these goals, hydrogen storage materials consisted of non-metal elements have been developed. Some of these, such as alanate (NaAlH₄), amide (LiNH₂) and borohydride (LiBH₄), will be also shown and the properties of these materials will be discussed.