SiO2@C Hollow Nanospheres As Anode for Lithium Ion Battery

Abstract Carbon-coated SiO 2 hollow nanospheres with different thickness of carbon layers have been synthesized using PAA as template and phenolic resin as carbon source. The hollow structure provides space for the bulk expansion of SiO 2 when it works in lithium ion batteries. The carbon layer on the surface of SiO 2 hollow nanosphere significantly inhibits the bulk expansion of SiO 2 and improves the lithium ion transfer rate. By comparing silica materials coated with carbon layers of different thicknesses, it was found that HSiO 2 @C-2 used as anode material in lithium-ion batteries exhibited the best electrochemical performance. It achieves a reversible capacity of 748.1 mA h g –1 after 250 cycles and shows excellent rate capability and excellent cycling stability. This is attributed to the improved diffusion conditions of lithium ions due to the suitable thickness of carbon layer, which effectively increases the electronic conductivity of the anode material.