Carbon-coated nitrogen doped SiOx anode material for high stability lithium ion batteries

Due to the inherent volume expansion effect and low conductivity of silicon monoxide (SiOx, 0 < x < 2), its cycling performance is seriously decreased at high rates. To solve this, SiOx was first doped with ammonium sulfate, then it was carbon coated with glucose. Finally, carbon-coated nitrogen doped SiOx (N doped SiOx@C) was successfully obtained. This strategy can enhance the electronic conductivity, ionic conductivity and solve the serious volume expansion problem of silicon-based anode materials to a great extent. This synergistic effect brings up greatly improvement on its electrochemical performance, N doped SiOx@C anode exhibits a high specific capacity retention rate of 91.4% after 100 cycles at a high rate of 1.05 A g(-1). The method adopted is characterized by its flexibility, simplicity and efficiency.