Investigation on the Corrosion Resistance of V3TiNi0.56Mx Hydrogen Storage Alloy in Alkaline Solution

Vanadium-based hydrogen storage alloys are easily corroded in KOH solution, which leads to their poor electrochemical cyclic durability in alkaline solution and limits their application in the Ni/MH battery. In this paper, the structure transformation of V3TiNi0.56Mx alloys during full immersion corrosion in alkaline solution was investigated; the corrosion potentials, the Tafel curves and the impedance spectra were tested for the V3TiNi0.56Mx alloys in alkaline solution. The results show that the corrosion of V3TiNi0.56Mx alloys in alkaline solution is caused by the continuous dissolve of the TiNi compound based phase as a micro-current collector, and the addition of alloy elements Cr and Al can prevent the dissolve of TiNi compound based phase, shift the alloy corrosion potential and improve the corrosion resistance of alloys in alkaline solution.