Enhanced electrochemical performances of LiNi0.5Mn1.5O4 spinel via ethylene glycol-assisted synthesis
Enhanced electrochemical performances of LiNi0.5Mn1.5O4 spinel via ethylene glycol-assisted synthesis
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DOI：
10.1016/j.electacta.2009.12.001
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发表时间：
2010-02
影响因子：
6.6
通讯作者：
Xianfa Zhang;Jing Liu;Haiying Yu;Guiling Yang;Jiawei Wang;Zijia Yu;Haiming Xie;Rongshun Wang
中科院分区：
文献类型：
--
作者：
Xianfa Zhang;Jing Liu;Haiying Yu;Guiling Yang;Jiawei Wang;Zijia Yu;Haiming Xie;Rongshun Wang
采用了一种简单有效的合成LiNi0.5Mn1.5O4尖晶石的方法--乙二醇辅助共沉淀法。乙二醇络合剂能实现金属离子在原子尺度上的均匀分布，防止LiNi0.5Mn1.5O4颗粒长大。X射线衍射分析表明，所制备的材料为纯相的立方尖晶石结构(Fd3m)，没有任何杂质。扫描电子显微镜照片显示其为团聚结构，一次粒径小于100 nm。电化学测试表明，所制备的LiNi0.5Mn1.5O4具有高容量和优异的倍率性能。在0.1C倍率下，其放电容量为137mAhg−1，约为理论容量(146.7mAhg−1)的93.4%。在5C的高倍率下，它仍能提供117mAhg−1的放电容量，50次循环后的容量保持率超过95%。这些结果表明，所制备的LiNi0.5Mn1.5O4是一种很有前途的高功率锂离子电池正极材料。
A simple and effective method, ethylene glycol-assisted co-precipitation method, has been employed to synthesize LiNi0.5Mn1.5O4spinel. As a chelating agent, ethylene glycol can realize the homogenous distributions of metal ions at the atomic scale and prevent the growth of LiNi0.5Mn1.5O4particles. XRD reveals that the prepared material is a pure-phase cubic spinel structure (Fd3m) without any impurities. SEM images show that it has an agglomerate structure with the primary particle size of less than 100nm. Electrochemical tests demonstrate that the as-prepared LiNi0.5Mn1.5O4possesses high capacity and excellent rate capability. At 0.1C rate, it shows a discharge capacity of 137mAhg−1which is about 93.4% of the theoretical capacity (146.7mAhg−1). At the high rate of 5C, it can still deliver a discharge capacity of 117mAhg−1with excellent capacity retention rate of more than 95% after 50 cycles. These results show that the as-prepared LiNi0.5Mn1.5O4is a promising cathode material for high power Li-ion batteries.