Deposition characteristics and behaviour of high-pressure cold-sprayed silicon powder

Abstract

The high-pressure cold spraying technology was adopted to deposit silicon particles on the copper substrates for preparing the silicon-based electrode of lithium-ion batteries. The deposition of silicon powder was accomplished at two spray process parameter sets by impacting the particle stream or individual particle. The microstructure and the morphology of the silicon coatings were characterised by scanning electron microscopy. A single-silicon particle represents three different deposition behaviours. The mass gains of as-sprayed samples are negative over multiple spray passes, but the thin silicon coating with the particular covered structures is formed. Increasing the number of spray pass cannot cause the obvious increase in the coating thickness. The interfacial morphology of the silicon coatings indicates that, except for the plastic deformation of the copper substrate, both the mechanical interlock effect among the deposited silicon particles and even the chemical binding contributing to the effective bond of silicon particles to the substrate.