Corrosion behaviour of Zr1−xTixV0.6Ni1.2M0.2 (M=Ni, Cr, Mn) AB2-type metal hydride alloys in alkaline solution

Effects of Vanadium/Nickel Contents in Laves Phase-Related Body-Centered-Cubic Solid Solution Metal Hydride Alloys

“…The introduction of Laves phases promotes good absorption kinetics [7], easy formation due to its brittleness [8][9][10], and high surface catalytic activity through a synergetic effect [11]. Many works have been reported in this family of alloys that partially replace Ti, V, and Cr with other transition metals for improvements in both hydrogen storage [9,[12][13][14][15][16][17][18][19] and electrochemical applications [20][21][22][23]. Our contributions to the field include the introduction of a high hydrogen pressure activation process [24], an optimization of annealing conditions (900 °C for 12 h) [25], and a study examining the contributions of the constituent elements in Laves phase-related BCC solid solutions.…”

Structural, thermodynamic, and electrochemical properties of TixZr1−x(VNiCrMnCoAl)2 C14 Laves phase alloys

“…An atomic ratio of Ti/Zr in the range of 0.4-0.55 has been shown desirable for a high hydrogen storage capacity, and for high hydrogen absorption and desorption rates [36]. Further, it has been suggested that the corrosion resistance can be improved by optimization of Zr:Ti ratio (wherein an optimized Zr:Ti ratio is between 1 and 3) [23]. Still further, studies of Zr 1−x Ti x Mn 1−y V y Ni 1−z M z (where M = Al, Co, and Fe) alloys showed better cycling performance with x = 0.4-0.6 than x < 0.4 [38].…”

“…Functions for each modifier have been reviewed before [35,36,[46][47][48][49]. To summarize, vanadium modifiers increase the M H bond strength and thus contribute to a higher hydrogen storage capacity and an improved high temperature discharge [47]; chromium modifiers improved discharge rate [49] and charge retention [47] by preventing the formation of V-Mn phase, which is more corrosive than the matrix C14 phase [23,48]; manganese modifiers increase the mutual solubility of other element during solidification; Co and Al modifiers modify the surface oxide in order to facilitate the formation process and improve the cycle life [47]. The amount of Co and Al additives can be optimized in relation to battery performance characteristics, such as activation, rate capability, and cycle life [8].…”

Electrochemical characteristics of titanium-based hydrogen storage alloys

“…Discharge and cycle life behavior of Zr 0.5 Ti 0.5 V 0.6 Ni 1.4 alloy when a fraction (0.2 at.%) of the Ni-component is substituted by Cr or Mn has been reported by Kim et al [3]. The Zr:Ti component ratio variation to extend the cycle life of high capacity of Mn-substituted alloy Zr 1−x Ti x V 0.6 Ni 1.2 Mn 0.2 (x = 0.0, 0.25, 0.5, 0.75) has also been investigated.…”