Synthesis, structural, magnetic and electrochemical properties of LiNi sub(1/3)Mn sub(1/3)Co sub(1/3)O sub(2) 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 LiNi sub(1/3)Mn sub(1/3)Co sub(1/3)O sub(2). X-ray diffraction (XRD) shows that the powder adopts the [alpha]-NaFeO sub(2) layered structure with space group R3m. 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 3.0-4.2V in which only the Ni is electrochemically active. This fatigue, however, has no sizeable impact on the capacity: the initial capacity [approximate]150 mAh g super(-1) was retained at the 10th cycle (ca. 97%).