Preparation of dual-shell Si/TiO2/CFs composite and its lithium storage performance
(1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Hunan Provincial Key Laboratory of Electronic Packaging and Advanced Functional Materials,
Changsha 410083, China)
2. Hunan Provincial Key Laboratory of Electronic Packaging and Advanced Functional Materials,
Changsha 410083, China)
Abstract: A dual-shell Si/TiO2/CFs composite was synthesized through a simple method to deal with the intrinsic drawbacks of silicon-based anode, in terms of huge volume change, unstable SEI films, and low electronic and ionic conductivity. The inner rigid TiO2 shell alleviates the huge volume expansion of the nano silicon, and the outer resilient carbon fiber, which is porous and staggered, is beneficial to the rapid transport of electrons and ions. The as-prepared Si/TiO2/CFs composite displays a superior reversible specific capacity of 583.4 mA·h/g, high rate capability and decent cycling performance. The dual-shell encapsulation method provides a guideline for other anode materials with huge volume expansion during the cycling process.
Key words: dual-shell; Si-based anode; electrospinning; sol-gel method; lithium-ion batteries