Co3O4 nanorods are prepared by a facile calcinations of the Co-composites, which is synthesized with the precursors of CoCl2, 1,3,5-Benzenetri carboxylic acid (H3BTC) and phenanthroline (PHEN). The Co-composites nonorods are about 1 um long and 50nm wide. After calcinations, the Co3O4 nanorods are composed of nanoparticles of 20–40nm in queue and possesses a surface area of 23m2 g−1 owning to the release of the organic molecules. The electrochemical properties are examined by cyclic voltammetry, electrochemical impedance spectroscopy and cyclic charge-discharge tests. The results show that the Co3O4 have the highest specific capacity of 262Fg−1 at 5mVs−1 in the range of 0.2–0.7V (vs. Ag/AgCl) and have a good cycle life with nearly no decrease after 500 cycles at 50mVs−1. The asymmetrical Co3O4//AC button cell is also tested by two-electrode system with a large potential testing window of 1.5V and the results show the high energy density with a value of 42.81Whkg−1 at the discharge current of 1.5Ag−1.