Preparation of manganese oxide with high density by decomposition of MnCO3 and its application to synthesis of LiMn2O4

Manganese oxide with high tap density was prepared by decomposition of spherical manganese carbonate, and then LiMn2O4 cathode materials were synthesized by solid-state reaction between the manganese oxide and lithium carbonate. Structure and properties of the samples were determined by X-ray diffraction, Brunauer-Emmer-Teller surface area analysis, scanning electron microscope and electrochemical measurements. With increase of the decomposition temperature from 350 degrees C to 900 degrees C, the tap density of the manganese oxide rises from 0.91 g cm(-3) to 2.06 g cm(-3). Compared with the LiMn2O4 cathode made from chemical manganese dioxide or electrolytic manganese dioxide, the LiMn2O4 made from manganese oxide of this work has a larger tap density (2.53 g cm(-3)), and better electrochemical performances with an initial discharge capacity of 117 mAh g(-1), a capacity retention of 93.5% at the 15th cycle and an irreversible capacity loss of 2.24% after storage at room temperature for 28 days. (C) 2008 Elsevier B.V. All rights reserved.