We report the fast charge–discharge Li ion battery based on the nanostructural controlled Na0.44MnO2 wires with high aspect ratio. The good fast charge–discharge property is observed because the single crystalline Na0.44MnO2 nanowires have a high electronic conductivity as electrode active materials of lithium ion battery due to the one-dimensional single crystalline nanowire. Moreover, such nanosize structure could reduce the required lithium diffusion length in the active materials to the several tens of nanometer, also reduce the effective specific current density by high surface area, and increase the stability of cycle performance by the one-dimensional single crystalline structure.