Engineering iron sulfide/carbon co-coated silicon nanoparticles as lithium-ion battery anode displaying stable capacity and rate-performance

Abstract

Engineering optimal Si-based composites for Li-ion battery is significant. Here, we develop an iron sulfide (FeS) and carbon co-coated Si (Si@FeS/C) as high-performance anode. The Si@FeS/C structure reduces the formation of non-stable solid electrolyte interface, enabling good capacity and stability. The Si@FeS/C anode maintains 809 mAh g-1 at 0.1 A g-1 along with a Coulombic efficiency of 98% after 50 cycles, and displays a capacity of 669 mAh g-1 after 100 cycles at 0.2 A g-1. In addition, it displays a good stability at 50 °C. These findings provide a potential strategy for engineering coatings on Si to achieve high performances.