Controllable Multilayer of High-performance Si/C Anode Materials Synthesized at Low Temperature from Industrial Ca-Si Alloy and CCl4 for Lithium-ion Batteries

Abstract

A simple and energy-saving synthesis process for the high-performance Si/C anode material of lithium-ion batteries is advantageous for application. In this paper, the layered Si/C composite was synthesized by a low temperature one-pot synthesis from industrial Ca−Si alloy and CCl₄. The effect of synthesis temperature on the structure and performance of the products was investigated. We found that low temperature favors to the multilayer structure of Si/C. Taking the advantage of the layered structure, the Si/C-300 anode material prepared at the temperature of 300 °C has good electrochemical performance of a reversible capacity of more than 1000 mAh g⁻¹ at a current density of 2 A g⁻¹ for 300 cycles, with a capacity retention ratio of 82.8 %, and an ICE of 77.0 %. At a high current density of 6 A g⁻¹, the specific discharge capacity of 721.6 mAh g⁻¹ can be achieved. The synthesis method provides a promising route to high performance silicon-carbon anode materials.