锂离子电池正极材料LiMn2O4的制备及其电化学性能的研究

锂离子电池具有比能量高、质量轻、体积小、电压高、安全性好和无记忆效应等特点,而正极材料是其研究的重点.采用溶胶-凝胶法合成了锂离子电池的正极材料,结果表明,其初始容量高,循环性能理想,并且整个合成过程也较为简单,合成的温度相对较低,样品的颗粒比较均匀.

Preparation of LiMn2O4 as Cathode Materials of Lithium Ion Batteries and Its Electrochemical Properties

Lithium ion batteries were intensively used in the field of portable computer and communication. If one doubles the specific capacity of the positive electrode, e.g. by using an oxide that could reversibly intercalate 1 Li instead of 0.5 Li per 3d-metal, one could increase the specific capacity of the cell by 68%. In contrast, if one doubles the specific capacity of the negative electrode, one could increase the overall specific capacity of the cell by only 12%. Thus, to improve the specific capacity of lithium ion batteries, we should dedicate our effort to the synthesis of new positive electrode materials, i.e.. Vacious lithiated oxides that could reversibly intercalate one Li atom per 3d-metal atom at about 4 V versus Li. LiMn 2O 4 is a promising candidate for cathode because of its high voltage, low coat and nonpolluting for environment. Sol-gel method is used to synthesize the cathode materials recently. The material has a high first-discharge capacity and long cycle life, and the synthetic process is simple: it reacts at a low temperature and the sample particle is uniform in size.