Si/Ni3Si-Encapulated Carbon Nanofiber Composites as Three-Dimensional Network Structured Anodes for Lithium-ion Batteries

Si/Ni3Si-encapulated carbon nanofiber composites are synthesized by a facile one-pot electrospinning method and employed as three-dimensional network structured anode materials for lithium ion batteries. It is demonstrated that the composite exhibited increased cycling performance with a reversible capacity of 1132.4 mAh g−1 after 200 cycles, which is 45% higher compared to the bare Si. The improved battery performance is attributed to the alloying of Si with Ni, which could effectively alleviate the volume expansion during lithium insertion/extraction. In addition, the formation of one dimensional nanofiber in which Si/Ni3Si nanoparticles are well distributed not only increases the electronic conductivity, but also enhances the mechanical strength of the electrodes, resulting in increased cycle stability.