Nano-scale Silicon-Carbon Anodes for High Capacity Lithium Ion Batteries

Equipment and ordnance in the Defense arsenal, ranging from complex electronic systems for silent watch, sensors, hybrid vehicles, portable soldier systems, and unmanned vehicles, are becoming increasingly reliant on battery power for mission operations. In the Phase I research, Applied Sciences, Inc. (ASI) demonstrated feasibility of producing silicon-coated carbon nanofiber anode materials with specific capacities in excess of 1500 mAh/g to moderate cycle numbers sufficient to meet needs for UAVs and selected spacecraft applications, and further stabilizing the anode material through addition of conductive carbon coatings to achieve high capacity retention rates. ASI proposes to build upon the successes of the Phase I effort in developing silicon-carbon anodes that can triple the specific energy and volume of existing lithium ion batteries, with focus on a conductive layer on the surface of the silicon, and the insertion of silicon into a nanoscale graphitic structure to achieve coulombic efficiencies over 99% for 500 cycles. ASI has developed relationships with DOE Laboratories for characterization of the silicon-carbon anodes before, during, and after cycling to assist the development of strategies to boost performance. ASI will work with its supply chain of Yardney Technical Products and General Motors to fabricate prismatic, prototype batteries for evaluation.