Improved capacity and rate capability of Ru-doped and carbon-coated Li4Ti5O12 anode material

Pure Li4Ti5O12, modified Li4Ti5O12/C, Li4Ru0.01Ti4.99O12 and Li4Ru0.01Ti4.99O12/C were successfully prepared by a modified solid-state method and its electrochemical properties were investigated. From the XRD patterns, the added sugar or doped Ru did not affect the spinel structure. The results of electrochemical properties revealed that Li4Ru0.01Ti4.99O12/C showed 120 and 110 mAh/g at 5 and 10 C rate after 100 charge/discharge cycles. Li4Ru0.01Ti4.99O12/C exhibited the best rate capability and the highest capacity at 5 and 10 C charge/discharge rate owing to the increase of electronic conductivity and the reduction of interface resistance between particles of Li4Ti5O12.It is expected that the Li4Ru0.01Ti4.99O12/C will be a promising anode material to be used in high-rate lithium ion battery.

► By using a simple one-step solid-state reactions method synthesizes Li4Ru0.01Ti4.99O12/C anode material.
► Combining the Ru-doped and carbon-coated techniques to fabricate Li4Ru0.01Ti4.99O12/C effectively enhance the diffusion rate of Li+ and significantly reduce surface electronic resistance of Li4Ti5O12.
► Li4Ru0.01Ti4.99O12/C delivers 120 and 110 mAh g−1 at 5 and 10 C charge/discharge rate, respectively, after 100 charge/discharge cycles.