A new electrode material for nickel–metal hydride batteries: MgNiPt alloy prepared by ball-milling

Structural and electrochemical properties of MgNi-based alloys with Ti, Pt and Pd additives

“…6-8 clearly show that this phenomenon is not related to any nickel corrosion, confirming that the key factor of the performance degradation is the Mg corrosion [8,19]. As mentioned before [9], the enhanced stability of the Pt-containing alloy may be due to the presence of a Pt surface layer, which partially blocks the Mg corrosion. Unfortunately, such an effect could not be confirmed because of the impossibility of obtaining XANES spectra at the Mg edge, at the LNLS XAS beam line.…”

“…The addition of other transition metal elements, such as Ti, Pd and Pt, has been reported to improve to some extent the electrochemical stability of the Mg-Ni-based alloy electrodes [8,9]. In recent papers, it has been observed that Pt is as effective as Ti for improving the electrode cycle life [8].…”

“…These oxide films may retard the formation of the Mg(OH) 2 phase improving the lifetime of the electrode. For Mg-Ni-Pt alloys, the improvement may be due to the formation of a Ptrich surface layer, which acts as a protective coating for the Mg in the bulk of the particle, retarding the formation of the Mg(OH) 2 phase, because of the high stability of metallic Pt in alkaline medium [9].…”

Structural and electrochemical characteristics of Mg(55−)Ti Ni(45−)Pt metal hydride electrodes

“…The improved cycling stability observed in this alloy system was ascribed to the formation of a multi-oxide passive layer composed by a number of Pd and Ti oxides which could reduce the oxidation of Mg [29]. The addition of Pt to Mg-Ni alloy electrodes was reported by the first time by Souza et al [30]. These authors observed that the addition of only 2 at.% of Pt was enough to increase the maximum discharge capacity and improve the cycling performance of the alloy electrode.…”

“…Souza et al [30] investigated the simultaneous substitution of Pt for Ni and Mg in the Mg 50 Ni 50 alloy. The general composition Table 1 Parameters of electrochemical performance for the binary and ternary alloys.…”