Synthesis of sub-10 nm copper sulphide rods as high-performance anode for long-cycle life Li-ion batteries

•Copper sulfide (CuS) nanorods were successfully synthesized.•A facile sol–gel method without using template and complicated treatment was used.•The as-prepared CuS nanorods as anode achieve great electrochemical performance.

Copper sulfide (CuS) nanorods with the size of sub-10 nm are synthesized via a facile sol–gel method without post–thermal treatment. The as-prepared CuS nanorods are characterized by X-ray diffraction, transmission electron microscope, and energy dispersive X-ray spectroscopy as hexagonal covellite CuS. The as-prepared CuS nanorods utilized as anode material exhibit a high reversible capacity and excellent cycling stability up to 250 cycles, as well as high Coulombic efficiency. The unique structure of the CuS nanorods should be responsible for their excellent electrochemical performance.