The electrochemical behavior of chemically prepared alpha-phase Al-substituted Ni(OH)(2) was investigated in relation to its crystallinity. alpha-phase samples with 5-20% Al were prepared by precipitation and the crystallinity was tailored by changing the metal/alkali ratio or the aging temperature. A highly crystallized sample was obtained without controlling the reaction pH. Both the utilization and half-discharge potential increased as the sample crystallinity improved. A maximum capacity of 381 mAh/g and utilization of 190% were obtained. The crystallinity dependence of the cell performance was explained by the reduction of polarization because of a more ordered structure which led to a faster solid-state reaction.