Preparation of fine single crystals of spinel-type lithium manganese oxide by LiCl flux method for rechargeable lithium batteries. Part 1. LiMn(2)O(4)

Uniform ne single crystals of LiMn(2)O(4) spinel were synthesized by a LiCl-Mn(NO(3))(2) flux method. The effects of reaction temperature and time on the composition, size and morphology of lithium manganese oxide were investigated by chemical, X-ray diffraction and selected area electron diffraction analyses, and SEM observation. The composition and size of the single crystals depended strongly on the heating temperature. Stoichiometric LiMn(2)O(4) single crystals were yielded at 850degreesC, whereas lithium-rich and lithium-poor crystals were obtained at 650-750degreesC and 950degreesC, respectively. Plate-like Li(1.18)Mn(2)O(4.28) single crystals with a thickness of less than 0.1 mum, showed a high first discharge capacity of 112 mAh g(-1) with a good cycle feature. The increase in the size of single crystals resulted in a decrease of the capacity at the first cycle, but did not accelerate the capacity fade over the following cycles.