Synthesis of LiNiO2 by heat-treatment of Li(OH). H2O and Ni(OH)(2) is reported. The influence of synthesis conditions on the electrochemical performance of the resulting LiNiO2 is investigated. Thermal analysis of the synthesis process shows that LiNiO2 formation proceeds through the transformation of Ni(OH)(2) to a layered compound Ni1-x(OH)(2-x), followed by solid reaction with LiOH. The most favorable condition is heating a mixture of Li(OH). H2O and Ni(OH)(2) at 650 degrees C, and then at 720 degrees C in oxygen. The resulting LiNiO2 exhibits a considerably high discharge capacity of 145 mA h g(-1) and a sufficiently long cycle-life when cycled over a lithium composition range of 0.2 less than or equal to x less than or equal to 0.65.