Electrochemical studies of the Si-based composites with large capacity and good cycling stability as anode materials for rechargeable lithium ion batteries

The Si-C and Si-M-C (C, the disordered carbon) composites prepared from pyrolysis reaction and high-energy mechanical milling process have a significant enhancement in the electrochemical cycling stability over pure silicon. The introduction of the hard co-milling components (M, such as TiB2 and TiN) in the Si-C composite before pyrolysis reaction brings an improvement in the charging rate and cycling performance, but it leads to a slight loss in the reversible capacity. The full cell with the composite anodes and the LiCo0.2Ni0.8O2 cathode was fabricated to show large anode capacity over 600 mAh g−1 within a potential range of 2.3-3.9 V that might result in a high energy density. The Si-based composites appear to be the promising anode candidates for Li-ion batteries.