Al-substituted α-nickel hydroxide is modified by coating with pure β-nickel hydroxide in an attempt to improve its cycling performance. The crystal structure and morphology of the prepared samples are examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical performances of the bare and the β-nickel hydroxide coated Al-substituted α-nickel hydroxides are characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and charge/discharge tests. The results show that a β-nickel hydroxide coating on Al-substituted α-nickel hydroxide decreases the charge-transfer resistance and increases the specific discharge capacity. In particular, the enhancement of the capacity retention of β-nickel hydroxide coated Al-substituted α-nickel hydroxide is significant, maintaining 92.5% of the maximum capacity after 100 cycles at a charge/discharge rate of 0.5 C, whereas that of bare Al-substituted α-nickel hydroxide is only 53.6%.