Si/SiC/C in-situ composite microspindles as anode materials for lithium-ion batteries

Abstract

Si/SiC/C in-situ composite microspindles are fabricated through the magnesiothermic reduction of the Zn2SiO4/C nanowire bundles obtained from a one-pot hydrothermal synthesis. The SiC and C components in the composite are generated in situ and thus uniformly distributed within the microspindle particle at the nanoscale level. SiC strengthens the structure of the composite microspindle, and amorphous carbon acts as a highly efficient conductive and buffering medium. As anode materials for lithium-ion batteries, the Si/SiC/C composite microspindles deliver a reversible charge capacity of 1510 mAh g-1, an initial coulombic efficiency of 78.7% as well as a capacity retention of 89.9% after 200 cycles when tested at the current density of 100 mA g-1, and also exhibit superior rate capability. The significantly improved electrochemical performance over pure Si microspindles indicates that the composition and structural design of Si/SiC/C composite microspindles are quite efficient.