The present paper introduces a new method to prepare nano-NiOOH by oxidizing and cracking spherical Ni(OH)2 of nano-structure in NaClO–NaOH solution. The prepared samples were characterized by X-ray powder diffraction (XRD), field emission scan electronic microscope (FESEM) and transmission electron microscopy (TEM). Results indicate that the synthesized sample is nano-NiOOH rod of 60–150nm in width. The charge/discharge tests show that the nano-NiOOH cathode shows good cycling reversibility at high current density of 10,000mAg−1, provides a high capacity of 276mAhg−1 and reduces the charge time to as short as 1.83min. Furthermore, the nano-NiOOH still keeps a reversible capacity of 93.7% after 120 cycles at a super high charge/discharge current of 10,000mAg−1, showing a good charge/discharge property.