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

This Small Business Innovation Research Phase II project proposes to develop and commercialize surface-engineered silicon anodes for use in lithium-ion batteries. Silicon has a ten fold greater charge capacity than graphite but its practical use as an anode material is hindered due to the mechanical problems associated with lithiation cycles (cracking, pulverization) and unwanted chemical reactions at silicon surfaces. Electrochemical Materials (EM) has developed wet surface functionalization methods enabling silicon nanoparticles to be reversibly cycled without mechanical failure or deleterious side reactions. In this work, EM will develop the surface chemistry and integration methods to create anodes for tablet-size (4000mA?h) lithium- ion batteries. EM will develop a scalable manufacturing process and demonstrate batteries with surface-engineered silicon nanoparticles. The new anodes will allow batteries to reach capacities 30 to 40% higher than conventional lithium-ion batteries for more than 1000 cycles. The broader impacts/commercial potential of this project is that higher capacity lithium-ion batteries will be quickly realized in portable electronics and electric vehicles. Lithium-ion batteries have revolutionized portable communications and electric vehicle power sources, yet their materials of construction have remained essentially unchanged since the mid 1980?s. If successful, the commercialization of surface-engineered silicon nanoparticles in lithium-ion anodes would result in 30 to 40% capacity gains along with an approximately 20% drop in cost per watt. Cell phones, tablets, and laptop users could use portable devices for longer periods between charging intervals. Electric vehicles with lithium- ion batteries could increase driving ranges by 40% and improve their cost competitiveness with gasoline-powered vehicles. Electrochemical Materials has strong relationships with major specialty chemical manufacturers, battery materials providers and battery manufacturers and intends to use NSF research and development funds to commercialize their innovative capacity-enhancing anode material.