Julien, C.Amdouni, A.Castro-García, SocorroSelmane, M.Rangan, S.2015-02-092015-02-092006-03Julien CM, Amdouni A, Castro-Garcia S, Selmane M, Rangan S. LiCo1-yMyO2 positive electrodes for rechargeable lithium batteries: II. nickel substituted materials grown by the citrate method. Materials Science and Engineering B: Solid-State Materials for Advanced Technology 2006;128(1-3):138-500921-5107http://hdl.handle.net/2183/14031[Abstract] 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 5 h 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 1 M 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. 187 mAh/g upon 32 cycles.engLithium nickel–cobalt oxidesLithium diffusivityLithium secondary batteriesCitric acidChelating agentSol–gel methodjournal articleopen access