Facile preparation and electrochemical properties of amorphous SiO2/C composite as anode material for lithium ion batteries

An amorphous SiO2/C composite anode material is synthesized via a sol–gel route combining with mechanical milling and post heat-treatment processes. The synthesized amorphous SiO2/C composite presents a nanostructure composing of amorphous SiO2 cluster and coating carbon layer. The amorphous SiO2/C electrode exhibits high reversible capacity (∼600 mA h g−1), stable cycling performance and excellent rate-capability. Mechanical milling causes SiO2/C composite amorphization which makes the active material possess good electrochemical activity. The coating carbon layer can not only increase electronic conductivity, but also accommodate part of the volume expansion occurred during discharge/charge process. [Display omitted] ► Amorphous SiO2/C composite was prepared via a facile route. ► SiO2/C electrode exhibits high specific capacity and stable cycling performance. ► SiO2/C electrode displays excellent rate-capability. ► Amorphous SiO2 shows higher electrochemical activity than crystalline one.