Electrochimica Acta, Vol.113, 313-321, 2013
Synthesis, structural, magnetic and electrochemical properties of LiNi1/3Mn1/3Co1/3O2 prepared by a sol-gel method using table sugar as chelating agent
Table sugar (sucrose) was used as a new and cheap chelating agent to prepare LiNi1/3Mn1/3Co1/3O2. X-ray diffraction (XRD) shows that the powder adopts the alpha-NaFeO2 layered structure with space group R(3) over bar m. The high value of c/a above 4.97 indicates a well-ordered rhombohedral lattice. The refined degree of cationic mixing of 2.4% remains fixed upon cycling. The fatigue of the material used as a positive electrode of a Li-cell has been investigated by scanning and transmission electron microscopy (SEM and TEM) as well as the magnetic measurements in the initial, charged and discharged state at low C/10 rate over the 10th first cycles. Small cracks are observed after cycling, despite the low C-rate and the voltage range limited to 3.0-4.2 V in which only the Ni is electrochemically active. This fatigue, however, has no sizeable impact on the capacity: the initial capacity approximate to 150 mAh g(-1) was retained at the 10th cycle (ca. 97%). (C) 2013 Elsevier Ltd. All rights reserved.