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Hydrogen Storage Alloys

Hydrogen storage alloys are metallic materials that have a unique ability to reversibly absorb and release significant amounts of hydrogen from the gas phase or electrochemically (see image below). This unique property of hydrogen storage alloys is used in numerous applications1 such as:

  • rechargeable batteries
  • cooling devices
  • hydrogen storage systems for fuel cells

Among the broad variety of hydrogen storage alloys that have been studied to date,1,2 two groups of materials, AB5 and AB2 type alloys, have the most advantageous combination of high hydrogen storage capacities and operations parameters.

AB5 alloys combine a hydride forming metal A, usually a rare earth metal (La, Ce, Nd, Pr, Y or their mixture known as Mischmetal), with a non-hydride forming element - nickel. The latter can be doped with other metals, such as Co, Sn or Al, to improve materials stability or to adjust equilibrium hydrogen pressure and temperature required for its charging discharging with hydrogen.2

AB2 alloys, also known as Laves phases, represent a large group of alloys containing titanium, zirconium or hafnium at the A-site and a transition metal(s) at a B-site (Mn, Ni, Cr, V and others). Reversible hydrogen storage capacities of this group of materials are comparable with those of AB5-type alloys. However, AB2 alloys are capable of storing additional amounts of hydrogen at high hydrogen pressures and have higher capacities at high discharge rates when used as negative electrodes in batteries.2

References:
1. Hydrogen Materials Science and Chemistry of Metal Hydrides, NATO Science Series, v.71. Eds.: M.D.Hampton, D.V.Shur, S.Y.Zaginaichenko, V.I.Trefilov, Kluwer Academic Publishers, Dodrecht, Boston, London, 2002.
2. Battery Technology Handbook, 2nd Ed., Ed.: H.A.Kiehne, Expert Verlag GmbH, Renningen-Malsheim, Germany, 2003.
Electrochemical Hydrogenization / Electrochemical Charging
Gas Phase Hydrogenization

Product #

Description

Molecular Formula

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685933 Lanthanum-nickel alloy hydrogen-storage grade Green Alternative LaNi5
768596 Lanthanum-nickel-aluminum alloy hydrogen-storage grade, 99.9% trace metals basis Green Alternative LaNi4.5Al0.5
685968 Lanthanum-nickel-cobalt alloy hydrogen-storage grade Green Alternative La2Co1Ni9
685976 Mischmetal-nickel alloy hydrogen-storage grade Green Alternative (Ce, La, Nd, Pr)Ni5
685941 Titanium-manganese alloy hydrogen-storage grade Green Alternative TiMn2
693928 Yttrium-Nickel alloy, YNi5 99.9% trace metals basis Green Alternative YNi5
693804 Zirconium-scandium-iron alloy Green Alternative Zr4Sc1Fe10