SmPO4-coated Li1.2Mn0.54Ni0.13Co0.13O2 as a cathode material with enhanced cycling stability for lithium ion batteries
SmPO4-coated Li1.2Mn0.54Ni0.13Co0.13O2 as a cathode material with enhanced cycling stability for lithium ion batteries
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SmPO4包覆Li1.2Mn0.54Ni0.13Co0.13O2作为正极材料，增强锂离子电池的循环稳定性
DOI：
10.1016/j.ceramint.2017.01.052
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发表时间：
2017-04-15
影响因子：
5.2
通讯作者：
Zhang, Yuheng
中科院分区：
文献类型：
--
作者：
He, Lei;Xu, Junmin;Zhang, Yuheng
采用沉淀法制备了SmPO4包覆Li1.2Mn0.54Ni0.13Co0.13O2阴极材料，并在450℃下进行了煅烧。采用x射线衍射、扫描电镜、高分辨率透射电镜、电子衍射谱、恒流循环、循环伏安法和电化学阻抗谱（EIS）研究了原始样品和包覆样品的晶体结构和电化学性能。研究发现，表面涂覆SmPO4后，富锂正极材料的电化学性能得到了显著提高。其中，2 wt%的smpo4包覆样品表现出最佳的循环性能，在1℃速率下循环100次后，容量保留率为88.4%，大大优于原始样品的72.3%。SmPO4涂层不仅通过减少氧的损失稳定了阴极结构，而且保护了富锂阴极材料不与电解质发生副反应，提高了锂离子在阴极界面的迁移速率。
SmPO4 coated Li1.2Mn0.54Ni0.13Co0.13O2 cathode materials were prepared by the precipitation method and calcined at 450 degrees C. The crystal structures and electrochemical properties of the pristine and coated samples are studied by X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, electron diffraction spectroscopy, galvanostatic cycling, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). It has been found that the electrochemical performances of the Li-rich cathode material have been substantially improved by SmPO4 surface coating. Especially, the 2 wt% SmPO4-coated sample demonstrates the best cycling performance, with capacity retention of 88.4% at 1 C rate after 100 cycles, which is much better than that of 72.3% in the pristine sample. The improved electrochemical properties have been ascribed to the SmPO4 coating layer, which not only stabilizes the cathode structure by decreasing the loss of oxygen, but also protects the Li-rich cathode material from side reaction with the electrolyte and increases the Li+ migration rate at the cathode interface.