Abstract：MnO₂ and MnO₂-Graphene composites as anode material for lithium-ion batteries were synthesized by a conventional hydrothermal route. The samples were investigated by X-ray diffraction, scanning electron microscopy, galvanostatic charge-discharge, cyclic voltammetry and AC impedance methods. The present results indicated that the synthesized MnO₂ is β-MnO₂, which is a length of 1 ~2 μm, and the diameter of the nanorods within 200 nm. The β-MnO₂-GNs composites present a good discharge specific capacity of 659.8 m A·h/g at a current density of 0.1 C after 60 cycles,the retention rate of discharge capacity is 46.4% and have a excellent rate capability of418 m A·h/g at a current density of 5 C.

Keywords: graphene; manganese dioxide; lithium-ion batteries; electrochemical properties