Silicon cages with tailored mesopores as anodes for high rate performance lithium ion batteries

Abstract

Silicon (Si) with high energy density is identified as the most promising candidate for commercial lithium-ion batteries anodes. Unfortunately, the volume expansion severely damages the battery cycle life during cycling, resulting in fast capacity fading during the battery operation. Herein, a facile design was proposed for the preparation of novel tailored mesoporous Si cages (TMSC) to mitigate this issue. The TMSC material, with mesoporous anamorphic spherical shells and nano-sized Si cores, consists of numerous interconnected channels and forms a half open three-dimensional network. When evaluated as electrode material for lithium-ion batteries, it exhibits the reversible capacity of 931.1 mAh/g after 200 cycles at 1 A/g, which is more stable than that of Si pomegranates with intact shells. Moreover, it displays a high rechargeable capacity of 552.3 mA h/g over 500 cycles at 4 A/g and the capacity decay ratio is only 0.11% for each cycle.