Nanostructured SiOx/Si composite confined by carbon layer as anode materials for high-performance lithium-ion battery

Abstract

Owing to its extremely high capacity, availability, and abundant resources, silicon anode is an excellent option for the future generation of high-energy-density lithium-ion batteries. Nevertheless, because of its significant volume expansion and low conductivity, it is less applicable in practical applications. Herein, we constructed a SiOx/Si with good dispersion obtained by hydrolytic polymerization and aluminothermic reduction, then the SiOx/Si/C (SSC) composite was prepared by carbon coating. The as-prepared samples have a thin layer of carbon which can improve electrical conductivity and buffer the volume expansion of Si. The optimized SSC-14 anode material has a high specific capacity and excellent cyclability (1355 mA h g−1 at 0.2 A g−1 after 350 cycles). Additionally, the SiOx/Si/C-14 composite has exceptional structural stability and may preserve 78.11 % of its original shape after 350 cycles. The SiOx/Si/C-14 composite material synthesized in this work might offer a new idea for design of future lithium-ion battery anode materials.