The Ca-3(PO4)(2) coating was attempted to improve the oxygen evolution of Ni(OH)(2). The Ca-3(PO4)(2) and Co(OH)(2) coated Ni(OH)(2) was prepared by coating of Ca-3(PO4)(2) on the surface of Ni(OH)(2), followed by coating of Co(OH)(2) on its surface. The cyclic voltammetry analysis showed that the oxygen evolution potential increased after the coating both at room temperature and 60 degrees C, indicating that the coating could effectively enhance the oxygen evolution potential in the charge process. The difference between oxygen evolution potential and oxidative potential increased from 26 mV to 47 mV at 60 degrees C, leading to the improvement of charge acceptance at 60 degrees C. (c) 2006 Elsevier B.V. All rights reserved.