Synthesis and upscaling of silicon nanoparticles for lithium-ion batteries in a hot-wall reactor

Small amounts of silicon are currently used to partly replace graphite as anode material in lithium-ion batteries to increase their energy density and fast charging capability. Ensuring mechanical integrity during charging and discharging as well as the production of suitable silicon-based materials on a large scale at acceptable costs still remains a challenge. In this work, the formation of silicon nanoparticles from the gas phase is analyzed to understand the process, identify key parameters regarding a suitable process technology, and resolve upscaling issues for transfer to the industrial pilot scale. The experimental findings are supported by simulations of fluid dynamics. Process conditions regarding the formation of pure as well carbon containing nanoparticles are studied and a successful transfer to an industrial pilot plant reactor is demonstrated.