锂离子蓄电池正极材料LiMn_2O_4的研究进展

Research progress on cathode material LiMn_2O_4 for lithium-ion batteries

从制备方法、比容量、循环性能、高温性能等几方面对近年来有关LiMn2 O4尖晶石的研究作了综述。烧结温度、氧分压及冷却速度是影响高温固相反应产品性能的关键因素 ,软化学合成方法具有一些固有的优点 ;合成高n(Li)∶n(Mn)比的Li1 +xMn2 O4、对LiMn2 O4进行化学嵌锂、或同时利用 3V +4V两个平台的容量可以提高比容量 ;以低价金属离子掺杂、阴 /阳离子同时掺杂、或合成非整比化合物可以改善循环性能 ;过渡金属的掺杂还将改变充放电曲线 ,导致容量向高电位区转移 ;锰的溶解及其引起的结构变化是导致高温下锂锰尖晶石容量衰减的原因。

Recent research progress on LiMn 2O 4, including its synthesis, specific capacity, cycleability and the high-temperature performance were reviewed. Sintering temperature, partial oxygen pressure and cooling rate are the key factors affecting the performance of the samples prepared by solid state reactions. The soft chemistry methods provides some additional advantages. Li 1+xMn 2O 4 synthesized with slightly high n(Li)∶n(Mn) ratio, chemical lithiation of LiMn 2O 4, or simultaneous utilization of 3 V+4 V plateaus can deliver high capacity. Partial substitution of Mn and/or O by other elements improves cycleability of LiMn 2O 4, and also modifies its operating curves, which leading to its capacity transfer to higher potential than 4 V. Dissolution of Mn and resultant structural change causes capacity fading at high temperature.