Silicon has played a critical role in the modern world economy, particularly through its prominent role in the semiconductor industry. Silicon also has the potential to revolutionize the energy storage industry because it is one of the most promising anode materials for next-generation lithium-ion batteries. However, well-designed silicon anodes often require elaborated synthesis methods requiring the use of toxic chemicals, making it difficult to embrace these methods for widespread applications of silicon anodes. This award will address this deficiency by investigating a novel, simple and scalable nanomanufacturing method to produce silicon anodes with well-designed hierarchical structures at low cost and with no involvement of toxic chemicals. The research work leads to a nanomanufacturing method that is scalable at industry level and that can fabricate silicon/carbon nanocomposites with well-designed internal structures and unprecedented performance for next-generation lithium-ion batteries. The availability of new anode materials paves the way to enable broad market penetration of electric vehicles, extend cell phone working hours to multiple days before recharging, broaden the application areas of batteries including military usage, and make the technology greener and more energy efficient. The project offers undergraduate students opportunities to participate in research through a semester long Inter-professional Project. Presentations on "Roles of Chemistry in Lithium-ion Batteries" with hands-on demonstrations are planned in the science classes of high schools with high percentage of under-represented minority students. These activities are designed to inspire high school stucents to pursue careers in science, engineering and technology.
This project is the first to investigate a simple and scalable nanomanufacturing method that can fabricate Si anodes with a well-designed hierarchical structure that combines features of nanoscale Si building-blocks, conductive coatings and engineered void space plus in-situ formation of graphene. This well-engineered hierarchical structure offers Si anodes with large specific-capacity, high specific power and long cycle life as well as high areal capacity. This nanomanufacturing method starts with commercially available micron-sized Si and graphite particles, which are subjected to high-energy ball milling during which graphene is produced in situ. The entire nanomanufacturing process and powder handling is carried out in ambient environment except during the high-energy ball milling and carbon coating processes, making this nanomanufacturing method easily scalable at industrial levels. The project leads to a nanomanufacturing method to fabricate hierarchical silicon/carbon nanocomposite anodes with unprecedented properties and performance at low cost and without the use of toxic chemicals.
