CoTiO3-reinforced TiO2 composite hollow microspheres for high-capacity and long-cycle-life lithium ion battery anodes

Titania (TiO 2 ) is widely recognized as an intercalation-type anode material with favorable parameters of low cost, abundant reserves, high safety, and long life. However, electrode kinetics within TiO 2 is limited, resulting in a theoretical capacity below 335 mAh g −1 . Here, CoTiO 3 was fused with anatase (A)/rutile (R) biphasic TiO 2 to construct multi-scale hybrid CoTiO 3 /A/R-TiO 2 –2 hollow microspheres with a TiO 2 content of about 90 % in this work. The average particle size of the CoTiO 3 /A/R-TiO 2 –2 anode was about 1.97 μm, with a high specific surface area of 76.67 m 2  g −1 , a pore volume of 0.16 cm 3  g −1 , and a large pore size of 8.55 nm. When deployed as an anode in a lithium-ion battery, it provided a high reversible specific capacity of 455 mAh g −1 after 500 cycles at 0.5C. After repeated charge/discharge cycles, a solid electrolyte interphase (SEI) film rich in conducting LiF was formed on the surface of the electrode. Therefore, the high capacity of the anode was mainly attributed to the stable multi-scale hybrid CoTiO 3 /A/R-TiO 2 hollow microspheres and the thin, uniform SEI film. This strategy provided a viable solution for the design of long-life, high-capacity conventional oxide semiconductor anodes.