SiO2/Carbon Composite Microspheres with Hollow Core–Shell Structure as a High‐Stability Electrode for Lithium‐Ion Batteries

Abstract

AbstractThe SiO2/carbon composite material used as a lithium‐ion battery (LIB) anode was synthesized by aerosol spraying a mixture of polyvinyl alcohol (PVA) solution and SiO2 nanoparticles, followed by coating polyacrylonitrile (PAN) on the SiO2/PVA surface and an annealing treatment at 800 °C. The as‐prepared SiO2/po‐C@C has a hollow core–shell structure. The hollow section contributes to accommodate the volume expansion of SiO2 nanoparticles; the skeleton of porous carbon in the core not only enhances the electronic conductivity, but also provides the lithium‐ion diffusion path; the PAN‐based carbon shell benefits for forming a stable solid electrolyte interphase (SEI) film. This core–shell structure could partly alleviate the pulverization of the SiO2/po‐C@C particles and also perform excellent electrochemical performances. Compared with the SiO2@C composite, the SiO2/po‐C@C composite possesses a high specific charge capacity of 669.8 mA h g−1 at a current density of 100 mA g−1 after 100 charge and discharge cycles with a high capacity retention of 98.6 %. Therefore, the SiO2/po‐C@C composite with a hollow core‐shell structure shows great potential as an anode material for future LIBs.