Self-adaptive Si/reduced graphene oxide scrolls for high-performance Li-ion battery anodes

Abstract

A Si/C composite with Si nanoparticles (nSi) uniformly dispersed in the interlayers of reduced graphene oxide scrolls (rGS) is successfully developed for high-performance Li-ion battery anodes. The rGS can deform reversibly with the repeated expansion/contraction of nSi to maintain contact between the nSi and the conductive rGS network, which can effectively buffer large volume changes and maintain continuous large-area core-shell electrical contact. Additionally, the continuous electrical network of rGS greatly enhances the electrical conductivity, and the open structures at the ends and sides of rGS provide paths for rapid diffusion of Li ions, thus enhancing the rate performance. By virtue of the rational design, the composite shows a high reversible specific capacity of 2030 mA h g(-1) at 0.2 A g(-1), high cycling stability of 1200 mA h g(-1) at 4 A g(-1) with 99.2% capacity retention after 200 cycles, and an excellent rate performance of 1000 mA h g(-1) even at 8 A g(-1).