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The effect of Mo-addition on hydrogen storage and low-temperature electrochemical performances of La-Mg-Ni-Co-AI alloys is investigated.The alloys were synthetized via vacuum induction melting followed by annealing treatment at 1123 K for 8h.The major phases in the annealed alloys are consisted of (La,Mg)2Ni7,(La,Mg)5Ni19 and LaNi5 phases.Mo-addition facilitates phase transformation of LaNi5 into (La,Mg)2Ni7 and (La,Mg)5Ni19 phases.Hydrogen absorption/desorption PCI curves indicates that the hydrogen storage capacity of the alloy increases remarkably with the addition of Mo.Furthermore,the La0.75Mg0.25Ni3.05Co0.2Al0.05Mo0.2 alloy shows excellent hydriding/dehydriding kinetics with a higher capacity,requiring only 100 s to reach its saturated hydrogen capacity of 1.58 wt％ at low temperature of 303 K,and releasing 1.57 wt％ hydrogen within 400 s at 338 K.Electrochemical experiments manifest that the Mo-added alloy electrode has perfect activation properties and the maximum discharge capacity.The low-temperature dischargeability shows that the La0.75Mg0.25Ni3.05Co0.2Al0.05Mo0.2 alloy exhibits the excellent low-temperature discharge performance,and the maximum discharge capacity is improved from 231.0 to 334.6 mAh/g at 253 K.The HRD property of the alloy electrode is enhanced,suggesting that Mo enhances the kinetic ability at low-temperature.