| 초록 |
Silicon (Si) has been considered as one of the most promising anode materials for next-generation Li-ion batteries (LIBs) due to its high theoretical capacity (4200 mAh/g), which is about 11 times higher than that of graphite. However, Si anode suffers from extreme expansion/contraction when charging/discharging, resulting in electrical contact loss with current collector and degradation of electrochemical performances. Moreover, silicon has poor electrical conductivity to receive the electrons from current collector. To solve these problems, silicon needs supportive materials that can relieve huge volume change and improve electrical conductivity of silicon. Herein, Si@graphene nanoflakes (GF) composite was prepared by electrostatic interaction between aminated SiO2 layer on Si and GOF and following thermal annealing and HF treatment makes Si@SiO2@GOF into targeting material. Furthermore, GF coated on Si core improved the rate performance of silicon-based cell and cycling stability of the anodes due to buffering effect for volume change of anode material. As a result, the Si@GF composite realized the significantly superior capacity and capacitive stability. |
