The layered LiCo1−yNiyO2 microcrystalline powders were synthesized by a sol–gel method using citric acid as a chelating agent in the range 0.2≤y≤0.8. Submicron-sized particles of the precursor were obtained at temperature below 400°C and microcrystalline powders were grown by thermal treatment at 700°C for 5h in air. The carboxylic-based acid functioned such as a fuel, decomposed the homogeneous precipitate of metal complexes at low temperature, and yielded the free impurity LiCo1−yNiyO2 single-phases suitable for electrochemical applications. The synthesized products were characterized by structural, spectroscopic and thermal analyses. FT-IR measurements provide information on the growth process and the final local environment in the cationic sublattice of LiCo1−yNiyO2 solid solution. The electrochemical performance of the synthesized products in rechargeable Li cells was evaluated using non-aqueous solution 1M LiPF6 in EC-DMC as electrolyte. The electrochemical features of a series of LiCo1−yNiyO2 compounds (0.2≤y≤1.0) are discussed in relation with their synthesis procedure and substitutive amount. The substitution of Ni3+ for Co3+ in LiCo1−yNiyO2 for y=0.75 shows improvement of the specific capacity at ca. 187mAh/g upon 32 cycles.