Nanowire Cathode Material for Lithium-Ion Batteries

73202B03-I Increasing the high-rate capacity (or power) of lithium-ion batteries demands dramatic improvements in cathode materials. Conventional lithium-ion batteries use relatively low surface area, particulate-based cathode materials, which require conductive and binder additives for conductivity and mechanical integrity, respectively. This project will develop new nanowire lithium-ion cathode materials using electrodeposition-on-graphite technology. Nanowires with diameters down to 15 nanometers will increase active surface area by a factor of 100, enhancing power proportionately. The interconnectivity of nanowires will allow formulations with reduced inert conductive and binder additives, resulting in better performance than with nano particulates. In Phase I, graphite template nanowire synthesis techniques will be developed for ?-MnO2. The nanowires will be formulated and tested specifically as Li-ion battery cathodes. The nanowires will be synthesized, characterized, and optimized, and then incorporated into functional cathodes. Improvements in high-rate capacity will be measured. Commercial Applications and Other Benefits as described by awardee: The technology should increase the power of Li-ion batteries, making it possible to decrease the size and increase the reliability and safety of hybrid electric vehicle (HEV) batteries. Annual sales of HEV batteries are projected to grow to $3.5 billion by 2005. Commercial spacecraft manufacturers have very similar requirements for higher capacity, power, and lifetime. Communications satellites represent another large and growing market, given the large and growing interest in satellite-based TV, Internet access, and telecommunications.