Royal Society of Chemistry, Journal of Materials Chemistry A: materials for energy and sustainability, 24(3), p. 12709-12717, 2015
DOI: 10.1039/c5ta00964b
Full text: Download
Silicon is one of the most promising anode materials for lithium ion batteries due to its high-specific capacity. However, its poor cycling stability and rate capability limit its practical use. Herein, we report scalable fabrication of unique three-dimensional porous silicon/TiOx/carbon (Si/TiOx/C, 0<x<2) binder free composite electrode for lithium ion batteries. The TiOx/C frameworks were incorporated by a slurry coating method followed by heat treatment, resulting in well-connected three dimensional framework structure consisting of Si nanoparticles conformably embedded in conducting TiOx/C matrix. The porous TiOx/C conductive framework effective alleviates the volume change of Si during cycling and substantially improves the structural stability of electrode materials. Moreover, the amorphous TiOx/C conductive matrix provides high electrical conductivity and electrochemical reaction between Li and Si. As a consequence, the Si/TiOx/C exhibits a stable reversible specific capacity of 1696 mAh g-1 at 0.1 A g-1 after 100 cycles with 87% capacity retention, and superior rate capability (754 mAh g-1 at 15 A g-1). The exceptional performance of Si/TiOx/C electrode combined with the facile synthesis technique makes it promising for high energy lithium ion batteries.