Silicon-graphite composite anode materials with assembly structure by boron oxide auxiliary for high-performance lithium-ion batteries

Abstract

The assembly strategy for silicon-graphite composites is usually achieved by constructing weak interactions between silicon and graphite particles through various driving forces, which does not lead to the preparation of silicon-graphite composites with good interfacial compatibility. Inspired by the current application of boron oxide in the interface engineering of anode materials, this study proposes a novel assembly strategy with high efficiency and scalability. Substantial connections were formed at the interface between silicon and graphite by introducing boron oxide auxiliary in combination with high-speed fusion and low-temperature heating. The stability of the silicon-graphite assemblies was further enhanced by coating it with an additional layer of amorphous carbon. The resulting composite anode material exhibited a stable integrated structure. SiG@B₂O₃-C anode exhibits good long-term cycling stability with a high reversible capacity of 608 mAh·g⁻¹ at 0.1 A·g⁻¹ and a capacity retention of 87.10 % after 200 cycles. The results suggest that the novel assembly strategy using a boron oxide auxiliary is an efficient and promising approach for developing silicon-graphite anode material with stable structures at the silicon-graphite interface.