Synthesis and storage performance of the doped LiMn2O4 spinel
- 化学化工－已发表论文 
A series of spinel-doped lithium manganese oxides, LixMnyTizO4.00 (0.973 <= x <= 1.018, 1.893 <= y <= 1.959, z approximate to 0.050), LixMnyTizNimO4.00 (0.981 <= x <= 1.010, 1.903 <= y <= 1.951, z approximate to 0.050, m approximate to 0.030), LixMnyTizComO4.00 (0.953 <= x <= 1.004, 1.912 <= y <= 1.968, z approximate to 0.050, m approximate to 0.009), have been prepared using the solid-state reaction of a titanium-doped electrolytic manganese dioxide, lithium hydroxide, and doping agents. The oxides have been characterized using several advanced techniques, such as X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared analysis, Raman spectroscopy, thermogravimetric analysis, differential scanning calorimetry, cyclic voltammograms and charge/discharge cycles. The experimental results show that the Li0.973Mn1.893Ti0.048O4.00 sample, prepared at 600 degrees C, showed the best electrochemical performance during the charge/discharge tests and storage process in all samples. In the voltage region of 4.6-2.5 V, the initial capacities of the fresh, discharge-storage, and charge-storage cell for the Li0.973Mn1.893Ti0.048O4.00 sample are 206, 144, and 175 mA h g(-1), respectively. In the voltage region of 4.3-3.4 V, the capacity fade of the sample was 5.3% in 150 cycles. After being doped by titanium ions, the spinel Li0.973Mn1.893Ti0.048O4.00 exhibits a lower lattice constant and stronger Mn-O bond than a pure spinel does. (C) 2007 The Electrochemical Society.