Enhanced electrochemical properties of vanadium-doped titanium niobate as a new anode material for lithium-ion batteries

摘要

The Vanadium-doped TiNb2O7 (TNO) samples have been investigated as novel anode active materials for application in lithium-ion batteries. The samples are characterized by X-ray diffraction patterns (XRD), raman spectrum, scanning electron microscopy (SEM), transmission electron microscopy (TEM), galvanostatic charge-discharge tests, and cyclic voltammetry (CV) tests. The XRD results indicate that V-doping expands the lattice parameters of TiNb2O7 samples and facilitates the enhanced lithium ion diffusion. SEM and TEM results show that lattice expansion caused by V-doping doesn't significantly change the particle size distribution of TiNb2O7 samples. The electrochemical measurements indicate that the TiNb1.98V0.02O7 anode material displays a highly reversible capacity and excellent cycling stability. The initial discharge capacities of TiNb1.98V0.02O7 are 298.48 mAh g(-1) and 171.99 mAh g(-1) at 0.3C and 10C, respectively, indicating that the TiNb1.98V0.02O7 material can be utilized as a promising anode material for lithium-ion batteries. (C) 2015 Elsevier Ltd. All rights reserved.