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The effect of Mo-addition on hydrogen storage and low-temperature electrochemical performances of La-MgNi-Co-Al alloys is investigated. The alloys were synthetized via vacuum induction melting followed by annealing treatment at 1123 K for 8 h. The major phases in the annealed alloys are consisted of(La, Mg)_2Ni_7,(La,Mg)_5Ni_(19)and LaNi_5 phases. Mo-addition facilitates phase transformation of LaNi_5 into(La, Mg)_2Ni_7and(La,Mg)_5Ni_(19)phases. Hydrogen absorption/desorption PCI curves indicates that the hydrogen storage capacity of the alloy increases remarkably with the addition of Mo. Furthermore, the La_(0.75)Mg_(0.25)Ni_(3.05)Co_(0.2_Al_(0.05)Mo_(0.2)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 within400 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 La_(0.75)Mg0.25Ni_(3.05)Co_(0.2)Al_(0.05)Mo_(0.2)alloy exhibits the excellent low-temperature discharge performance, and the maximum discharge capacity is improved from 231.0 to 334.6 m Ah/g at 253 K. The HRD property of the alloy electrode is enhanced, suggesting that Mo enhances the kinetic ability at low-temperature.
The effect of Mo-addition on hydrogen storage and low-temperature electrochemical performances of La-MgNi-Co-Al alloys is investigated. The alloys were synthetized via vacuum induction melting followed by an annealing treatment at 1123 K for 8 h. The major phases in (La, Mg) _2Ni_7and (La, Mg) _5Ni_ (19) and LaNi_5 phases. The addition of LaNi_5 to (La, Mg) (0.75) Mg_ (0.25) Ni_ (3.05) Co_ (0.2_Al_ (0.05) Mo_ (0.2) ______________________________________ The hydrogen absorption / desorption PCI curves indicate that the hydrogen storage capacity of the alloy marked remarkably with the addition of Mo. ) 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 propert ies and the maximum discharge capacity. The low-temperature dischargeability shows that the excellent low-temperature discharge performance, the maximum value of La_ (0.75) Mg0.25Ni_ (3.05) Co_ (0.2) Al_ (0.05) Mo_ (0.2) The discharge capacity is improved from 231.0 to 334.6 m Ah / g at 253 K. The HRD property of the alloy electrode is enhanced, suggesting that Mo enhances the kinetic ability at low-temperature.