bstract: 5 V cathode material LiNio.5Mn1.5O4 was synthesized by the self-propagating combustion method with citric acid as the complexing agent. The effects of excess lithium and excess nickel on the structure, morphology and electrochemical properties of LiNio.5Mn1.5O4 were investigated. The results show that: the optimum excess amounts of lithium and nickel for LiNio.5Mn1.5O4 preparation are 9% and 7% (in mole ratio), respectively, when the calcination temperature is 820 "C, the calcination time is 12 h, the annealing temperature is 600 ℃ and the annealing time is 24 h. For the LiNio.5Mn1.5O4 synthesized under the above optimal conditions, its initial discharge capacity reaches 122.7 mAh · G-1, 98.5% of which is still remained after 20 cycles, and there is only one voltage plateau at around 4.7 V found in its initial charge/discharge curve.%采用柠檬酸络合自蔓延燃烧方法制备了5V正极材料LiNi0.5Mn1.5O4.分别考察了不同锂过量和镍过量对LiNi0.5Mn1.5O4材料结构、形貌和电化学性能的影响.结果表明:当焙烧温度为820℃,焙烧时间为12h,退火温度为600℃,退火时间为24 h时,制备LiNi0.5Mn1.5O4的最佳锂过量为9％(摩尔分数,下同),最佳镍过量为7％,在此条件下所制样品的首次放电比容量达到122.7 mA·hg-1,20次循环后的放电比容量保持率为98.5％,且只存在单一的4.7V平台.
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