Sol-gel synthesis of 5 v LiCuxMn2-xO4 as a cathode material for lithium rechargeable batteries

Spinel LiCuxMn2-xO4 (0.025 <= x <= 0.1) has been synthesized using oxalic acid as the chelating agent using a sol-gel method to obtain submicrometer-sized particles, good surface morphology, homogeneity, agglomeration, and high crystallinity involving, short heating time. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and thermogravimetric and differential thermal analysis were carried out for the physical characterization of the synthesized powder. The XRD patterns of LiCuxMn2-xO4 show the single-phase spinel product, which is in good agreement with the JCPDS card (35-782). SEM images show that the particles, on the average, are of 50 nm in size and are present as agglomerated clusters at all dopant levels. Electrochemical cycling studies of the compound were carried out between 3 and 5 V to understand the redox behavior Of CU2+ ions. The charge-discharge cycling studies of spinel material with Cu stoichiometry of x = 0. 1 calcined at 850 degrees C exhibit an initial discharge capacity of 130 mAh g(-1) and stabilized at 120 mAh g(-1). (C) 2008 The Electrochemical Society.