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Rare earth–Mg–Ni-based alloys with superlattice structures are novel anode materials for nickel metal hydride batteries, wherein A 5 B 19 -type alloys have been regarded as the replacement of the current commercialized A 2 B 7 -type alloys due to the superior discharge ability at high rates and cycling stability. However, it is still a challenge to further improve the hydrogen storage properties of the A 5 B 19 -type alloys in a low-cost approach. Herein, we select low-cost Mn and Fe elements to substitute Ni to further reduce the cost of an A 5 B 19 -type La 0.72 Y 0.13 Mg 0.15 Ni 3.70 Al 0.15 alloy and focus on their effects on the alloy's structure and hydrogen storage properties. Results show that the La 0.72 Y 0.13 Mg 0.15 Ni 3.65 Al 0.15 Fe 0.05 alloy features increased intrinsic gas-solid hydrogen storage ability of 1.44 wt% and hydrogen absorption enthalpy change of −22.9 kJ mol–1, which have been altered by 0.21 wt% and 7.3 kJ mol–1 in contrast to the La 0.72 Y 0.13 Mg 0.15 Ni 3.70 Al 0.15 alloy, respectively. Furthermore, the Fe substitution benefits capacity retention during electrochemical cycling compared to Mn, which maintains 87.5% and 62.4% after cycling 100 and 500 times. The Mn substitution results in superior rate capability compared to the alloy containing Fe. The work provides guidance for designing hydrogen storage alloys with superlattice structures to improve the electrochemical performance. • Pr 5 Co 19 -type alloys with low cost Mn and Fe substituted Ni are obtained. • Effect of Mn and Fe substituted Ni on hydrogen storage properties is clarified. • Fe substituted Ni increases hydrogen storage capacity from 1.23 wt% to 1.44 wt%. • Fe substitution rises the capacity retention from 52.6% to 62.4% at the 500th cycle. • Mn substitution optimizes the discharge ability at high rates. [ABSTRACT FROM AUTHOR]