Preparation of Li4Ti5O12/C composites using gel-cast method and its electrochemical performance

• Gel-cast method was used for the first time to synthesize Li4Ti5O12/C composite.
• Gel-cast method can control the particle size at sub-micrometer level.
• Li4Ti5O12/C composite synthesized with 10 wt.% AM shows the best performance.
• Its specific capacity reaches 157.5 mAh g− 1 at 0.1 C.
• The electrode shows good stability especially at a higher current rate.

Spinel Li4Ti5O12/C composites were synthesized using gel-cast technique with acrylamide (AM) as monomer and NN-methylenebis-acrylamide as crosslinking agent. Effects of the amount of AM on the performances of the as-prepared materials were investigated. SEM photographs show that the primary particle size decreases gradually with the increase of AM content from 5 wt.% to 15 wt.%. When the AM content reaches at 15 wt.%, the agglomeration of the particles becomes obvious. Electrochemical measurements show that the Li4Ti5O12/C composite prepared with 10 wt.% AM presents relatively higher specific capacity (157.5 mAh g− 1) and better cycling stability, especially at a higher current rate. Impedance measurement shows that its resistance is substantially lower than that of the other two, suggesting the improvement of the charge transfer process over the electrode surface.