An Investigation of Titanium/Silicon Oxide‐CNTs Anode Material for Lithium‐Ion Batteries

Abstract Discovering a high‐performance (high rate capability, high specific capacity, and good stability) anode material for automobile battery applications is a great challenge. A titanium/silicon oxide‐CNTs (Ti_mSi_nO_l‐CNTs) is synthesized and tested as anode material for lithium‐ion batteries. High specific capacity (278 mAhg⁻¹ at 100 mA g⁻¹), high rate capability (156 mAh g⁻¹ at 4000 mA g⁻¹), and good stability (maintains 278 mAhg⁻¹ after 200 cycles) are reached over Ti_mSi_nO_l‐CNTs. The as‐synthesized Ti_mSi_nO_l‐CNTs has a particle structure that Ti_mSi_nO_l encapsulates CNTs with CNTs ends stretching out of the particles. In the Ti_mSi_nO_l phase, the TiO₂ crystal seeds are formed and encapsulated in amorphous SiO_y boundaries, which have sub‐nano pores. The high performance properties of Ti_mSi_nO_l‐CNTs could come from the synergetic combination of (1) the excellent electronic conductivity of CNTs and the amorphous carbon in Ti_mSi_nO_l‐CNTs, (2) the high Li⁺ intaking capability of the TiO₂ crystal seeds, (3) the high electrochemical activity of SiO_y, (4) the high Li⁺ insertion/extraction kinetics in the small TiO₂ crystal seeds and the amorphous SiO_y with sub‐nano pores, and (5) the high volume change tolerance offered by the CNTs binder and the amorphous SiO_y.