Graphene and Carbon Nanotube Dual-Decorated SiOx Composite Anode Material for Lithium-Ion Batteries

In this study, a three-dimensional graphene- and carbon nanotube (CNT)-decorated SiO x composite material (SiO x -Gr-CNT) was synthesized. The dual carbon components were introduced by a simple one-step method of high-energy ball milling. The corresponding SiO x -Gr-CNT composite electrode exhibited superior lithium storage performance because the graphene and CNT components form a flexible network with high conductivity decorating on SiO x . The network is beneficial for the improvement of the conductivity of SiO x particles. The mechanical flexibility of the graphene and CNT components had a negligible volume effect, which could effectively suppress the volume expansion of SiO x and assist to form a durable solid electrolyte interphase film by separating SiO x particles from the electrolyte. Thus, the electrochemical properties of the corresponding SiO x -Gr-CNT composite electrode were effectively enhanced with a large reversible specific capacity of 1015.1 mA h g –1, which was maintained at 1046.6 mA h g –1 after cycling of 100 cycles with a capacity remaining exceeding 100% under a current density of 100 mA g –1 . The SiO x -Gr-CNT composite electrode also exhibited outstanding cycling performance under a large current density of 1 A g –1 with more than 800 mA h g –1 reversible specific capacity even after 200 cycles. The method used for the combination of the SiO x -Gr-CNT composite anode material is simple and mass productive and thus is promising for practical application.