Low-temperature Plasma Synthesis and Processing of Next-generation Battery Materials

Our society is experiencing a pressing need to transition from a traditional fossil-fuel-based economy to a renewable energy one. Developing more energy-dense Li-ion batteries is important and critically needed for such a transition. Energy density breakthroughs would enable more efficient utilization of intermittent renewable sources (wind and solar) and the production of improved electric vehicles (rapid charge and extended range). While this transition is anticipated to bring enormous societal and environmental benefits, current Li-ion battery technology has reached maturity. Incremental and insignificant improvements in battery energy density will not satisfy the growing customer demand nor enable the renewable energy future we desire. The need for new and improved battery materials is widely recognized within the energy industry and research communities as the main bottleneck towards realizing next-generation electrochemical energy storage solutions. The proposed solution is to develop silicon-based battery materials with energy density levels that substantially exceed the standard graphite anode material. Most importantly, the silicon-based material described in this SBIR proposal is carefully engineered so that it can be (a) processed on a large scale so that it can meet the demand of the rapidly growing battery market and (b) introduced into current anode formulations without the need of any change to current battery manufacturing schemes. In other words, the proposed new battery material is a “drop-in” additive that can be easily integrated into current battery architecture to provide an immediate boost in performance. The performance of silicon-based additives for batteries is strongly dependent on the quality of feedstock silicon powders. It has been found that silicon nanoparticles produced via a low-temperature plasma process are superior to commercially available ones, as they enable significant improvement in various battery performance metrics. The applicant proposes to develop its own pilot-scale low-temperature plasma reactor, primarily based on proprietary technology developed by the University of Minnesota. A critical novelty in this approach will be using trichlorosilane (SiHCl3) as the chemical precursor, as this is significantly less expensive and safer to handle than the most commonly utilized silane (SiH4). Completing this project will provide the applicant with silicon particles that are superior in quality and significantly less expensive than currently commercially available. This will, in turn, allow the applicant to make significant progress towards a minimally viable product and enter the commercialization phase.