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

Variations in structural, thermodynamic, and electrochemical properties due to partial replacement of Zr by Ti in stoichiometricTixZr1−x(VNiCrMnCoAl)2 AB2 alloys, have been studied. In particular, these properties are evaluated to determine the alloys' potential as a negative electrode material for high energy density nickel metal hydride batteries. Alloys having an x value of from 0.49 to 0.61 are dominated by a C14 Laves phase crystal structure. As Ti-content increases, lattice constants a and c decrease non linearly, the absolute value of hydride heat of formation decreases, the total gas-phase storage capacity decreases and the high rate dischargeability increases. However, the electrochemical capacity remains relatively constant.