Zinc-Reduced Mesoporous TiOx Li-Ion Battery Anodes with Exceptional Rate Capability and Cycling Stability

摘要

We demonstrate a unique synthetic route for oxygen-deficient mesoporous TiOx by a redox-transmetalation process by using Zn metal as the reducing agent. The as-obtained materials have significantly enhanced electronic conductivity; 20 times higher than that of as-synthesized TiO2 material. Moreover, electrochemical impedance spectroscopy (EIS) and galvanostatic intermittent titration technique (GITT) measurements are performed to validate the low charge carrier resistance of the oxygen-deficient TiOx. The resulting oxygen-deficient TiOx battery anode exhibits a high reversible capacity (similar to 180 mA h g(-1) at a discharge/charge rate of 1 C/1 C after 400 cycles) and an excellent rate capability (similar to 90 mAh h g(-1) even at a rate of 10 C). Also, the full cell, which is coupled with a LiCoO2 cathode material, exhibits an outstanding rate capability (>75 mA h g(-1) at a rate of 3.0 C) and maintains a reversible capacity of over 100 mA h g(-1) at a discharge/charge of 1 C/1 C for 300 cycles.