Microstructures and electrochemical characteristics of the La0.75Mg0.25Ni2.5Mx (M=Ni,Co; x=0–1.0) hydrogen storage alloys

Rare earth–Mg–Ni-based hydrogen storage alloys as negative electrode materials for Ni/MH batteries

“…Increase the lattice parameters and cell volumes [53,64,65,88,92,116,117] Decrease the plateau pressure and the hysteresis of hydrogen absorption and desorption Increase the hydrogen storage capacity Improve effectively the cyclic stability due to the decrease of cell volume change and the increase of the suface passivation Increase the electrochemical kinetics Mn…”

“…Recently, a new alloy family of AB 3 -or A 2 B 7 -type rare earth-magnesium-based alloys with high specific capacity and good rate dischargeability was developed as the most promising next generation negative electrode materials for high energy and high power Ni/MH batteries. Numerous investigations have been conducted for their practical applications [22][23][24][25][26][27][28][29][30][111][112][113][114][115][116][117][118][119][120][121][122][124][125][126][127][128][129][130], especially in China and Japan. However, no systematical survey has been carried out on this newly developed hydrogen storage electrode alloy.…”

Substitution effects on the hydrogen storage behavior of AB2 alloys by first principles

“…For the LaNi 5 -related intermetallic compounds, their thermodynamic and the electrochemical properties rely strongly on the substituted element and its content [19][20][21][22][23]. By mechanically alloying with the catalytic element like Pd or Ni, the thermodynamic properties, activation process and the hydriding/dehydriding kinetic of TiFe systems have been substantially modified [24][25][26], similar to the behavior observed in the Mg 2 Ni-based compounds [27][28][29][30].…”

The correlative effects of Al and Co on the structure and electrochemical properties of a La–Mg–Ni-based hydrogen storage electrode alloy

“…Multi-alloying A side with suitable amount of Ce [9][10][11], Pr [12], Nd [13], Zr [14], etc., and B side with Co [15,16], Al [17], Mn [18], Cu [19], etc., were investigated to improve the cycle stability. Besides, heat treatment of annealing [20,21] and specific fabrication method, such as melt-spinning [22], are also useful methods for the improvement of the cycle stability. However, annealing needs extra energy and melt-spinning reduces the cycle capacity greatly.…”

“…That means that excessive content of Co is not expected. However, the optimum values of Co content for the capacity and the cycle stability do not coincide commonly and they are also different for the alloys with different compositions [16,22,23]. To reduce the cost of the La-Mg-Ni-based alloys, low Co content [24,25] and even no Co [26][27][28][29] La-Mg-Ni-based alloys have attracted considerable attention.…”