Silicon/Carbon Nanoparticles Assembled with Multifunction Carbon Nanotubes/Sheets as High-Performance Anode of Lithium-Ion Batteries

Abstract

Silicon as an electrode material in the lithium-ion battery application scenario has been hindered by its significant volumetric expansion and intricate synthesis processes. In this research, we have successfully synthesized Si@C/carbon nanotubes/carbon sheets (Si@C-CNTs/CS) composites by employing a simple one-pot method along with modified magnesium thermal reaction, which involves melamine to prevent high temperature. The resulting multifunctional Si@C-CNTs/CS composites demonstrate enhanced stability during volume change in silicon, resulting in both higher capacity compared to conventional carbon coating layer and improved conductivity of the materials. The results indicate that the Si@C-CNTs/CS composites exhibit a high discharge-specific capacity of up to 2981.64 mAh g−1 at 0.5 A g−1 current density and retain a discharge-specific capacity of 1487.71 mAh g−1 even after 300 cycles. Therefore, the double-layer carbon network structure of carbon nanotubes/carbon nanosheets can provide an efficient and simple preparation method for high-performance Si-base anode materials in practical applications.