Metal hydride alloys with improved rate performance

摘要

Methods of preparing improved metal hydride alloy materials are provided. The alloys include a mixture of at least four of vanadium, titanium, nickel, chromium, and iron. The alloy is processed by at least one of thermal and physical treatment to generate a refined microstructure exhibiting improved kinetics when used as electrodes in MH batteries (e.g., higher discharge current). The thermal treatment includes rapid cooling of the alloy at greater than 10⁴ K/s. The physical treatment includes mechanical pulverization of the alloy after cooling. The microstructure is a single phase (body centered cubic) with a heterogeneous composition including a plurality of primary regions having a lattice parameter selected from the range of 3.02 Å to 3.22 Å and a plurality of secondary regions having a lattice parameter selected from the range of 3.00 Å to 3.22 Å and at least one physical dimension having a maximum average value less than 1 μm.