Preparation of silicon/carbon hybrid anodes for high performance lithium-ion batteries

Abstract

The design of Si carbon hybrid material with clever structure is considered to be an effective method to improve the performance of Si based anode of lithium-ion battery. Herein, we prepared a Si@SiO₂@C (SSC) composite materials by using Si nanoparticles (Si NPs) as Si source and Neoprene as carbon source. On the one hand, SiO₂ generated during calcination can effectively buffer the volume expansion of Si NPs. On the other hand, the Si@SiO₂ NPs are uniformly encased in flexible and conductive carbon derived Neoprene which can effectively buffer the volume change of Si NPs and accelerate the transport of electrons and ions across the whole electrode scale. After electrochemical testing, the reversible capacity of SSC electrode is 1042 mAh g^-1 after 500 cycles at a current density of 2 A g^-1, and the excellent rate performance of 798 mAh g^-1 can be achieved at a current density of 12 A g^-1. When matched with the LiFePO₄ cathode, the full battery can achieve excellent cycle stability and rate performance.