Li₄Ti₅O₁₂ Nanoparticles Embedded in a Mesoporous Carbon Matrix as a Superior Anode Material for High Rate Lithium Ion Batteries

A mesoporous Li 4 Ti 5 O 12 /C nanocomposite is synthesized by a nanocasting technique using the porous carbon material CMK‐3 as a hard template. Modified CMK‐3 template is impregnated with Li 4 Ti 5 O 12 precursor, followed by heat treatment at 750 °C for 6 h under N 2 . Li 4 Ti 5 O 12 nanocrystals of up to several tens of nanometers are successfully synthesized in micrometer‐sized porous carbon foam to form a highly conductive network, as confirmed by field emission scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, Raman spectroscopy, and nitrogen sorption isotherms. The composite is then evaluated as an anode material for lithium ion batteries. It exhibits greatly improved electrochemical performance compared with bulk Li 4 Ti 5 O 12 , and shows an excellent rate capability (73.4 mA h g −1 at 80 C) with significantly enhanced cycling performance (only 5.6% capacity loss after 1000 cycles at a high rate of 20 C). The greatly enhanced lithium storage properties of the mesoporous Li 4 Ti 5 O 12 /C nanocomposite may be attributed to the interpenetrating conductive carbon network, ordered mesoporous structure, and the small Li 4 Ti 5 O 12 nanocrystallites that increase the ionic and electronic conduction throughout the electrode.