Low-cost heterogeneous dual-carbon shells coated silicon monoxide porous composites as anodes for high-performance lithium-ion batteries.

To develop low-cost, high-capacity and long-life anode materials for lithium-ion batteries, glucose-C and F-doped C coated SiO composites with adjustable pore structure (p-SiO@gl-C@F-doped C) are synthesized by facile and scalable methods. The combination of the heterogeneous dual-carbon shells and porous structure significantly promotes the reaction kinetics of the electrode, effectively suppresses and buffers the volume expansion of SiO, and largely enhances the stability of solid electrolyte interface of the electrode. In a half cell, the optimized p-SiO@gl-C@F-doped C (7:3) composite shows a stable discharge capacity of 785 mAh g−1 at a current density of 200 mA g−1. The discharge capacity is maintained at 772 mAh g−1 after 200 cycles. At a current density of 400 mA g−1, the electrode shows a discharge capacity of 633 mAh g−1 after 500 cycles, with a capacity degradation of ∼0.0096% per cycle from the 2nd cycle to the 500th cycle. The full cell which is composed of the commercial LiFePO4 as a cathode and the optimized composite as an anode, exhibits high capacity and good cycling stability.