SBIR Phase I: Engineered Solid Electrolyte Interphase Films for Silicon-Based Lithium Insertion Anodes

This Small Business Innovation Research Phase I project proposes to develop and commercialize new types of silicon nanowire anodes which may be used to safely store large amounts of lithium for many types of lithium batteries. The key innovation involves unique functionalization and integration methods that enable nanowire anodes to be cycled reversibly for thousands of cycles without mechanical failure, agglomeration, or deleterious side reactions. Silicon nanowires will be fabricated via electroless etching, and chemically or electrochemically functionalized to improve their performance and capacity retention in a lithium-ion battery. The objective of this work is to develop novel silicon composite anodes that may undergo over 200 deep cycles with capacities of at least 1000 mA.hg-1. The broader impact/commercial potential of this project is to develop high capacity anode rechargeable lithium batteries with capacities of over 1000 mA.hg-1, which represents approximate doubling of cell capacity without a significant change in manufacturing or cost. There is a critical need for high energy density rechargeable batteries for next generation hybrid vehicles and fully electric vehicles. In a recent report, the U.S. Department of Energy pointed out that the primary obstacles to the widespread introduction of lithium-based batteries for electric vehicles are the relatively low specific energy and the relatively high cost per kWh. The proposed integration and surface engineering methods will address these problems allowing the safe storage of lithium in silicon anodes for current and future generations of lithium batteries.