New Materials to Improve the Performance of Lithium-Ion Batteries in HEV and PHEV Applications

Most of the active materials now being used in advanced rechargeable batteries, such as the family of lithium-ion systems, have been known for some time.  Some members of the technical community believe that new materials will be required to meet the cycling profiles of advanced Plug-In Hybrid Electric Vehicles (PHEVs), while also meeting the goals for cost, calendar life, and other properties.  The goal of this project is to increase the energy density of lithium ion batteries for PHEVs by using novel anodes based on transition metal phosphide-active materials. These phosphides possess three to four times the specific capacity of carbon-based active materials presently used in standard lithium ion batteries. At the same time, transition metal phosphides have high intrinsic rate capability, which makes them ideal for power-leveling performance in both PHEV and HEV applications. Commercial Applications and other Benefits as described by the awardee: Practical versions of the anodes would be expected to operate close to lithium potential and utilize at least twice the specific capacity of carbon-based electrodes. These anodes would operate against traditional lithium ion cathodes such as LiCoO2.