Low-Cost Encapsulation of Silicon-Based Nanopowders

As battery performance demands increase, manufacturers are pushing the limits of what conventional materials can achieve in higher and higher drain electronic devices; incremental improvements and cost reduction efforts are perpetually underway to allow the vehicular battery industry to meet and exceed the energy, power and lifecycle targets set forth by the auto industry. Simply stated, the stability of higher capacity silicon-based materials is insufficient. Surface coatings on battery materials (cathodes, anodes and separators) can provide generational gains to cell performance (lifetime, safety, etc.), oftentimes at lower adoption cost to the battery manufacturer, providing a unique value proposition that allows for a holistic approach toward achieving the 2022 cost and performance targets of $125/kWh. Hybrid organic-inorganic surface coatings on primary silicon-based nanopowders can permit robust cycling of these high-volumetric expansion materials, providing the needed generational gains to anode energy density, and new coatings will be developed to ensure the surface resistivity of the materials is not increased commensurately.
This SBIR program is optimizing the Molecular Layer Deposition (MLD) process for robust silicon-based nanoparticles, to put these materials on a pathway to scale-up using PneumatiCoat Technologies’ innovative and proven high-rate manufacturing systems. A successful Phase I project will demonstrate a low-cost pathway to achieving the EV Everywhere goals and establish a roadmap to allow for anodes that can surpass 1,000 cycles while exceeding capacities greater than 1,000 mAh/g. The MLD processes will be implemented in high-rate manufacturing systems required to meet the aggressive price targets at the required throughput goals of the auto industry. Coated high capacity anode materials will demonstrate > 99% efficiency in > 200 mAh full pouch cells. New surface coatings of strategic materials will be designed and applied via ALD in scalable systems, while even lower cost plasma-enhanced processes are developed. A scalable roadmap to surface-protected battery materials will be realized for vehicular and high-drain portable electronics products, alongside many military, aerospace and down-well oil and gas applications that increasingly benefit from adopting high performance Li-ion battery systems. This nanotechnology-driven solution will be manufactured domestically to achieve U.S. nanomanufacturing initiative goals.
Key Words – Silicon Anodes, Molecular Layer Deposition, Lithium Ion Battery, Robust and Safe Battery Materials, Nanomanufacturing, Stabilizing Coatings