Recycling Rare Earth Metals from Nickel Metal Hydride Batteries

This Phase I Small Business Innovation Research Project develops methods of recycling rare earth alloys from used nickel metal hydride batteries. Alloys of rare earth metal, nickel and other metals provide functional hydride storage materials that are critical to the operation of nickel metal hydride batteries and their applications. The current fleet of hybrid electric vehicles relies upon nickel metal hydride batteries. The first fleet of vehicles manufactured in the 2000’s will reach recycling age in the 2010’s. Nickel metal hydride batteries represent a billion dollar industry, and the growth will continue in hybrid electric vehicles, grid storage, and consumer electronic applications. Currently, end-of-life nickel metal hydride batteries find use as feedstock for stainless steel manufacturing. The practice disposes of the battery safely, but does not recover any rare earth elements, and shorts potential benefits for battery rare earth recycling, such as reduction in manufacturing cost and reliance on rare-earth mining. When nickel metal hydride is used for stainless steel, battery replacement and its market growth remains reliant on mined rare-earth metals. This project will recycle the rare earth material from used nickel metal hydride negative electrodes, making them useful for manufacturing new nickel metal hydride batteries. Positiveresults from this project will be the technical foundation for a new industry aimed at recycling advanced batteries from the growing fleet of hybrid electric vehicles. The consistent, low cost source of material coupled with low cost processing can help stabilize the manufacturing cost of nickel metal hydride batteries based upon spikes in the price of rare-earth elements and nickel metal. Current rare earth metal prices, with elements such as lanthanum ~ $150/kg, threaten the economic viability of nickel metal hydride batteries, which have a high safety and performance track record in todays hybrid electric vehicles. Successful recycling developed in this proposal an economic way for The Nation to conserve critical resources and establish the next generation of industrial infrastructure to serve the growing HEV market.