Improving the Cycling Stability of Si/Ni Negative Composite Through Introducing the SiOC Skeleton.

ABSTRACT

A Si/Ni/SiOC (SNS) composite structure with high efficiency and long-term cycling stability was synthesized by a cost-effective and scalable method. In this structure, a SiOC net with favorably physical and chemical stability acts as a skeleton to support and segregate Si-Ni mixed powders. The electrochemical performance of Si-Ni as a negative for Li-ion battery had been largely improved through introducing a stable SiOC skeleton structure as buffer base. Compared with Si-Ni mixed powders, the SNS composite negative exhibits excellent long-term cycling stability and capacity. Such SNS composite negative shows excellent cycling stability with a specific capacity of 505.5 mA· h · g(-1) and 84% capacity retention over 25 cycles at 0.2 C rate, which has the perspective application in the future high energy density li-ion batteries. In the meantime, the design and fabrication of this structure has the potential to provide a way for the other functional composite materials in the semiconductive field.