High rate capability performance of ordered mesoporous TiNb 6 O 17 microsphere anodes for lithium ion batteries.

We report the synthesis and application of ordered mesoporous TiNb6 O17 microspheres (M-TNO) using a one-step solvothermal method for the first time in lithium-ion batteries. The diameters of TiNb6 O17 microspheres are in the range from 2.2 to 2.4 μm with a mesopore size of about 35 nm, which promotes the electron and ion migration in charge/discharge processes. M-TNO shows a high specific capacitance (307.2 mA h g-1 ) at a low current density of 0.2 C and a long-term cycle life over 500 cycles as an electrode. The retentive capacity of the batteries is 77% of the initial cycle after 500 cycles. It is worth noting that M-TNO exhibits excellent rate capacity, which decreases slowly from 265.7 to 172.4 mA h g-1 with the current density increasing from 1 C to 30 C. The retentive capacity at a current density of 30 C is 65% compared to that at 1 C.