Effect of magnesium content and quenching rate on the phase structure and composition of rapidly solidified La2MgNi9 metal hydride battery electrode alloy

► La2MgNi9 was prepared by rapid solidification and studied by SEM, TEM and XRD. ► The alloy contains La2MgNi9, LaNi5, La3MgNi14 and LaMgNi4. ► Optimisation of the amount of Mg and cooling rates increase yield of La2MgNi9.