Co-Inlaid Carbon-Encapsulated SiO_x Anodes via a Self-Assembly Strategy for Highly Stable Lithium Storage

SiOx is a promising anode material for next-generation lithium-ion batteries, with high energy density and low cost. However, several issues, such as poor cycling stability, should be overcome before practical application. Here, gum arabic, a well-known natural gum with low cost, is used as a carbon source to form a uniform Co-inlaid carbon coating on SiOx by a facile and scalable self-assembly method using Co2+ as a “bridge”, during which Co2+ plays a key role. After carbonization treatment, the Co-inlaid carbon coating can effectively mitigate volume effects, enhance electrical conductivity, boost deep delithiation processes, and guarantee the structural integrity of SiOx-Co@C. Because of the unique Co-inlaid carbon coating, the SiOx-Co@C electrode displays much improved lithium-storage properties. The charging capacity of the SiOx-Co@C electrode at the 250th cycle is 1010.8 mA h g–1 with 84% capacity retention at 200 mA g–1. This work presents a facile and efficient strategy to construct a uniform multifunctional coating for improved electrochemical properties.