A nearly stoichiometric LiNiO2 (ca. 1% nickel on Li site disorder! was synthesized using a particulate sol-gel approach. The oxide exhibits a high capacity of 205 mAh/g under a moderate C-rate of C/2. By maintaining the defect concentration and eliminating any impurity phases during synthesis, it was possible to quantitatively investigate the influence of crystallite size alone on the electrochemical properties of LiNiO2. The electrochemical capacity was reduced by approximately 10% when the average crystallite size of the chemically synthesized oxide was increased from ca. 0.3 to 0.8 mum. Using the success of estimating the influence of crystallite size on the electrochemical properties of the nearly stoichiometric LiNiO2, an analytical study on the factors affecting the electrochemical properties of defective LiNiO2 was further conducted. The analysis indicates that the electrochemical properties of the oxide are more strongly influenced by the presence of defects on Li sites and impurity phases than by the crystallite size.