Abstract
Crystallographic and electrochemical characteristics of ball-milled Ti 45Zr 35Ni 17Cu 3 + xNi ( x = 0, 5, 10, 15 and 20 mass%) composite powders have been investigated. The powders are composed of amorphous, I- and Ni-phases when x increases from 5 to 20. With increasing x, the amount of Ni-phase increases but the quasi-lattice constant decreases. The maximum discharge capacity first increases as x increases from 0 to 15 and then decreases when x increases further from 15 to 20. The high-rate dischargeability and cycling stability increase monotonically with increasing x. The improvement of the electrochemical characteristics is ascribed to the metallic nickel particles highly dispersed in the alloys, which improves the electrochemical kinetic properties and prevents the oxidation of the alloy electrodes, as well as to the mixed structure of amorphous and icosahedral quasicrystalline phases, which enhances the hydrogen diffusivity in the bulk of the alloy electrodes and efficiently inhibits the pulverization of the alloy particles.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have