Enhancing Li-ion Battery Performance through the Integration of Si@TiO2 Core-Shell Nanoparticles with Natural Graphite

In this study, Si@TiO2 core-shell nanoparticles are synthesized using the peptization technique, resulting in a thin and uniform TiO2 coating layer over silicon nanoparticles. This coating layer serves the purpose of controlling the structural degradation of the silicon nanoparticles. These core-shell nanoparticles are then reinforced into the natural graphite with the potential to be used as a composite anode material (Graphite/Si@TiO2) for Li-ion batteries. The developed composite material exhibits an initial specific capacity of approximate to 675 mAh/g at 0.5 A/g, and after 100 cycles it retains the capacity of 75 %. Compared with Graphite/Si composite anode, the developed composite anode material shows improved cyclic stability. The pre-and post-cycling morphological analysis of Graphite/Si and Graphite/Si@TiO2 composite anode reveals the degradation behavior. It is assumed that the TiO2 coating provides a protective shield for the silicon particles, preventing their interaction with the electrolyte and causing less material to deposit over the anode surface. Electrochemical Impedance Spectroscopy (EIS) analysis supports these findings, with the Graphite/Si composite anode exhibiting higher resistance than the Graphite/Si@TiO2 anode. In conclusion, the study demonstrates the potential of using Si@TiO2 core-shell nanoparticles as a reinforcing agent for natural graphite to develop high-performance composite anode material for Li-ion batteries.