Significant impact on cathode performance of lithium-ion batteries by precisely controlled metal oxide nanocoatings via atomic layer deposition
Significant impact on cathode performance of lithium-ion batteries by precisely controlled metal oxide nanocoatings via atomic layer deposition
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DOI：
10.1016/j.jpowsour.2013.08.042
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发表时间：
2014-02-01
影响因子：
9.2
通讯作者：
Sun, Xueliang
中科院分区：
文献类型：
--
作者：
Li, Xifei;Liu, Jian;Sun, Xueliang
商用锂离子电池中的LiCoO 2在高截止电压下循环性能较差。在这项研究中，我们采用原子层沉积（ALD）技术，表面改性的LiCoO2材料与各种厚度控制的金属氧化物（TiO 2，ZrO 2和Al 2 O 3）涂层，以提高其电池性能。研究了金属氧化物涂层对LiCoO2电极电化学性能的影响。结果表明，采用ALD法在LiCoO2粉体上形成均匀致密的包覆层，会明显降低锂离子的扩散和电子传输，从而降低电池性能。相比之下，它揭示了预制LiCoO2电极上的直接涂层比LiCoO2粉末上的涂层性能好得多。进一步公开了经涂覆的LiCoO2电极的改进的电化学性能高度依赖于涂层材料。在三种涂层材料中，Al2O3涂层的循环稳定性最好，而ZrO2涂层的倍率性能最好。因此，建议涂层材料是功能特定的，并且为了阴极的最佳改进，应该寻求特定的涂层材料。皇冠版权所有（C）2013由爱思唯尔B.V.出版保留所有权利。
LiCoO2 in the commercial lithium ion batteries has been suffering from its poor cycling performance at high cutoff voltages. In this study, we employ an atomic layer deposition (ALD) technique to surface-modify a LiCoO2 material with various thickness-controlled metal oxide (TiO2, ZrO2 and Al2O3) coatings to improve its battery performance. The effects of the metal oxide coatings on the electrochemical performance of LiCoO2 electrode are studied in detail. It is demonstrated that a uniform and dense coating via the ALD route on LiCoO2 powder can lower the battery performance due to an obvious decrease in lithium diffusion and electron transport with the coating layers. In contrast, it is revealed that a direct coating on prefabricated LiCoO2 electrodes performs much better than a coating on LiCoO2 powders. It is further disclosed that the improved electrochemical performance of coated LiCoO2 electrode is highly dependent on the coating materials. Of the three coating materials, the Al2O3 coating results in the best cycling stability while the ZrO2 coating contributes to the best rate capability. It is thus suggested that the coating materials are functionally specific, and for the best improvement of a cathode, a particular coating material should be sought. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.