以四氧化三钴、碳酸锂为原料, 尿素为燃料, 用自蔓延高温合成法制备层状正极材料LiCoO 2, 并考察了尿素与钴摩尔比、预制炉温、热处理温度、热处理时间及锂与钴摩尔比等工艺条件对合成产物的结构、微观形貌和电化学性能的影响. 结果表明, 制备LiCoO2的工艺条件为: 锂与钴摩尔比1.05:1.00、尿素与钴摩尔比1:1、预制炉温和热处理800℃、热处理时间2h. 所得LiCoO2的放电比容量达155mAh/g, 循环10次后容量保持率为95%.
Lithium cobalt oxides (LiCoO2) powders were synthesized by self-propagating high temperature synthesis using urea as fuel. XRD, SEM and electrochemical method were used to investigate the effects of mole ratio of urea to Co, mole ratio of Li to Co, combustion temperature, annealing temperature and the annealing time on the performance of LiCoO2. The results show that self-propagating high temperature synthesis is beneficial to form the layer structure of LiCoO2. The optimum condition is obtained as follows: molar ratio of urea to Co is 1:1, molar ratio of Li to Co is 1:1, combustion temperature and annealing temperature are 800℃ and annealing time is 2h, Under the optimum condition, the discharge capacity of LiCoO2 is 155mAh/g, and its capacity retention is 95% after 10cycles.
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