Enhanced electrochemical performances of 5 V spinel LiMn1.58Ni0.42O4 cathode materials by coating with LiAlO2
Enhanced electrochemical performances of 5 V spinel LiMn1.58Ni0.42O4 cathode materials by coating with LiAlO2
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DOI：
10.1016/j.jpowsour.2013.03.143
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发表时间：
2013-10-01
影响因子：
9.2
通讯作者：
Zhang, Xinxiang
中科院分区：
文献类型：
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作者：
Cheng, Fuquan;Xin, Yuelong;Zhang, Xinxiang
通过在Mn0.79Ni0.21CO3前驱体上包覆Al 2 O3，然后与Li 2CO 3在900 ℃下烧结，制备了LiAlO 2表面改性的LiMn1.58Ni0.42O4尖晶石正极材料。X射线衍射和红外光谱分析表明，在煅烧过程中，铝离子不仅与Li 2CO 3反应形成了一层强化的LiAlO 2包覆层，而且还从包覆层表面迁移到球形颗粒内部。LiAlO 2表面修饰的LiMn1.58Ni0.42O4样品在倍率性能和循环性能方面表现出比裸样品更优异的电化学性能。特别地，1摩尔%的LiAlO 2表面改性样品在4C倍率下的放电容量为100.6mAh g（-1），而裸样品的放电容量仅为49.5mAh g（-1）。在55 ° C下，1摩尔% LiAlO 2表面改性的LiMn1.58Ni0.42O4样品显示出优异的循环性能，在150次循环后容量衰减小于5%。基于这些结果，在前驱体上涂覆以制备增强的LiAlO 2涂层将是提高5 V尖晶石正极材料电化学性能的有前景的方法。(C)2013 Elsevier B. V.保留所有权利。
LiAlO2-surface modified LiMn1.58Ni0.42O4 spinel cathode materials have been prepared by coating Al2O3 on Mn0.79Ni0.21CO3 precursors, followed by post-sintering with Li2CO3 at 900 degrees C. X-ray diffraction and FTIR analyses indicate that during the calcination process aluminum ions not only react with Li2CO3 to form a strengthened LiAlO2 coating layer but also migrate from the surface into the spherical particles. The LiAlO2-surface modified LiMn1.58Ni0.42O4 samples exhibit excellent electrochemical performance compared to that of the bare one in terms of rate capability and cyclability. In particular, the 1 mol.% LiAlO2-surface modified sample can deliver a discharge capacity of 100.6 m Ah g(-1) even at a high current density of 4 C-rate, while the bare one only has a discharge capacity of 49.5 m Ah g(-1). At 55 degrees C, the 1 mol.% LiAlO2-surface modified LiMn1.58Ni0.42O4 sample shows outstanding cyclability with less than 5% capacity fade after 150 cycles. Based on these results, coating on the precursors to prepare a strengthened LiAlO2 coating layer would be a promising method to enhance the electrochemical performance of 5 V spinel cathode materials. (C) 2013 Elsevier B.V. All rights reserved.