Chelation-Assisted Formation of Carbon Nanotubes Interconnected Yolk-Shell Silicon/Carbon Anodes for High-Performance Lithium-ion Batteries.

As a viable replacement to commercial graphite anodes, silicon (Si) anodes have gained much attention from academics because of their considerable theoretical specific capacity and appropriate reaction voltage. Nevertheless, some limitations still exist in developing silicon anodes, including significant volume expansion and poor electrical conductivity. Herein, the carbon nanotubes (CNTs) interconnected yolk-shell silicon/carbon anodes (YS-Si@CoNC) were prepared via the chelation competition induced polymerization (CCIP) approach. The YS-Si@CoNC anode, designed in this study, demonstrates improved performance. At the current density of 0.5 A g-1 and 1 A g-1, a capacity of 1001 mAh g-1 and 956.5 mAh g-1 can be achieved after 150 cycles and after 300 cycles, respectively. In particular, at the current density of 5 A g-1, the reversible specific capacity of 688 mAh g-1 is realized. The exceptional outcomes are mainly attributed to the internal voids that adequately alleviate the volumetric expansion and the CNTs and carbon shells that provide an efficient conducting matrix to fasten the diffusion of electrons and lithium-ions. Our research presents a convenient way of designing Si/C anode materials with a yolk-shell structure to guarantee impressive electrical conductivity and robust structural integrity for high-performance LIBs.