La–Mg–Ni Intermetallics for Hydrogen Storage and Electrochemical Power Sources

The paper summarizes the results of the studies of La–Mg–Ni based intermetallic compounds for reversible hydrogen sorption and electrochemical applications. The phase composition, hydrogen sorption and electrochemical characteristics of AB₅-, AB₃- and AB₂-types intermetallic compounds are considered. A comparative evaluation of the materials is carried out. It has been shown that the maximum capacity of electrodes with AB₃-type intermetallic compounds reaches 400 mA h/g, which is 25% higher than the capacity of electrodes based on AB₅-type (315 mA h/g) and 7.5% higher than the capacity of electrodes with AB₂-type intermetallic compound (370 mA h/g). AB₂-type intermetallic compounds demonstrate good performance at high discharge current densities, and the presence of lanthanum promotes rapid activation of the electrodes.