The V3O7 center dot H2O/CNT nanocomposite is synthesized by hydrothermal process with the induction of functionalized carbon nanotubes (CNTs). The analysis of X-ray diffraction (XRD) revealed that the crystal structure of the V3O7 center dot H2O nanobelts is orthorhombic. The X-ray photoelectron spectroscopy (XPS) results indicated that the mol rate of V5+/V4+ is 1.93. The field emission scanning electron microscopy (FESEM) images confirmed the V3O7 center dot H2O nanobelts have several micrometers in length and a few hundred nanometers in width. The electrochemical properties of the as-prepared V3O7 center dot H2O/CNT nanocomposite were studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge measurements as cathode material. Herein, the V3O7 center dot H2O/CNT nanocomposite exhibits excellent electrochemical properties and good cycling behavior with the 50th capacity of 183.8, 198.9 and 162.7 mAh g(-1) at the current density of 100, 200 and 500 mA g(-1), between 2.0 and 4.0 V, respectively. (C) 2013 Elsevier B.V. All rights reserved.