SYNTHESIS OF LITHIUM-MANGANESE OXIDES AS A CATHODE FOR LITHIUM SECONDARY BATTERIES.

研究了用自己研制的熔融浸渍法制备二次锂电池正极材料（锂锰氧化物）的工艺。主要研究了尖晶石LiMn_2O_4和Li_<0.33>MnO_<2'>两种材料。发现熔体浸渍法制备了两种锂化合物：LiNO_3和LiOH。在研究过程中，明确了熔融浸渍法具有以下优异的特点，使我们能够制备用于各种用途的理想陶瓷材料。a)产品成分易于控制。b)产品粒度可通过原料的选择来控制。c)产品比表面积可控制。d)产品出丝密度可控制。我们还发现化学计量LiMn_2O_4在循环过程中转变为可充电容量为120 mAh/g的稳定化合物。结果表明，化学计量LiMn_2O_4是一种有用的锂离子电池正极材料。

We have developed the preparation procedures of cathode materials(Lithium Manganese oxides)for lithium secondary batteries by melt-impregnation method developed by us. Two types of materials, 1)spinel LiMn_2O_4 and 2)Li_<0.33>MnO_<2'> were mainly studied. It is found that two types of lithium compounds, LiNO_3 and LiOH,are available to the melt impregnation method. In the course of study, it is clarified that the melt-impregnation method has following excellent features, which allow us to prepare desirable ceramic materials used for various purpose. a)Composition of product is controlled easily. b)Particle size of product can be controlled by the selection of raw material. c)Specific surface area of product can be controlled. d)Tapping density of product can be controlled.We have also found that stoichiometric LiMn_2O_4 is transformed to stable compound with rechargeable capacity of 120 mAh/g during the cycling. It shows that stoichiometric LiMn_2O_4 is useful materials as a cathode of Lithium-Ion batteries.