Nanosized double substituted LiNi gamma Co1-2yMn1+yO4 (Y=0.05, 0.1, 0.25 and 0.45) spinels have been synthesized by a single-step combustion-aided procedure, which use sucrose as fuel. The as prepared samples contained some amorphous organic impurities that were removed after a short heating at 400 degrees C. The samples have been characterized by X-ray diffraction, thermal analysis and transmission electron microscopy. Lattice parameter of the spinels increased with nickel content, and decreased from 400 to 600 degrees C, at which temperature stoichiometric spinets with particle size of approximate to 20 nm were obtained. The electrochemical properties of the 600 degrees C-treated samples in the 5 V region have been studied. The sample with composition LiNi0.45Co0.1Mn1.45O4 has shown the best electrochemical performance, with redox potential of 4.6V, capacity of 129.6mAh g(-1), cyclability of 99.6% per cycle, and retained the capacity up to 1C rate. (c) 2006 Elsevier B.V. All rights reserved.