Submicro-sized porous SiO2/C and SiO2/C/graphene spheres for lithium ion batteries

In order to improve electrochemical performance of inert SiO 2 anode for lithium ion batteries, submicro-sized porous SiO 2 /C and SiO 2 /C/graphene spheres with the same SiO 2 content (43 wt.%) have been synthesized through a simple suspension nebulization and spray pyrolysis method followed by carbonization, where the components of the spheres are mixed uniformly. The addition of graphene results in mesoporous structure of the SiO 2 /C/graphene spheres. The electrochemical performances of the porous SiO 2 /C and SiO 2 /C/graphene spheres have been evaluated, which indicate that the SiO 2 /C/graphene spheres exhibits much higher cyclic capacity and stability than SiO 2 /C with reversible capacity retention of 97% over 100 cycles. The graphene additives display very strong effects in reducing charge transfer resistance and improving structural stability of the porous spheres simultaneously. The mesoporous SiO 2 /C/graphene spheres are promising anode candidate for high energy-density lithium ion batteries. Graphical abstract ᅟ