High Energy Density Li-ion Batteries With Good Low Temperature Performance

High energy density Li-ion batteries that can operate over a wide temperature range are needed in a variety of military, space and commercial applications. The specific energy of Li-ion batteries can be enhanced by utilizing new cathode materials that have significantly higher energy density than that of state-of-the-art LiCoO2. Low temperature performance of Li-ion batteries can be improved by reducing the electrolyte resistance and enhancing the mass transfer across the electrode/electrolyte interface. This can be accomplished by raising the ionic conductivity of the electrolyte and reducing the size of electrode particles, respectively. The proposed program focuses on developing novel nanostructured cathode materials with an energy density of ~ 800 Wh/kg, which is almost 50% higher than that of the practical energy density of LiCoO2. Working in collaboration with a leading developer of Li-ion batteries, in Phase I, we will demonstrate that it is possible to produce a stable high energy density nanostructured cathode by controlling the structure and composition of nanoparticles. As part of the Phase I work, a low temperature electrolyte will be used in Li-test cells to evaluate the electrochemical performance of nanostructured cathodes at sub-zero temperatures. In Phase II, prototype batteries will be fabricated and tested for performance, along with optimization and scaling of the synthesis process for producing electrode nanoparticles.