Boosting lithium ion storage of lithium nickel manganese oxide via conformally interfacial nanocoating
Boosting lithium ion storage of lithium nickel manganese oxide via conformally interfacial nanocoating
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通过共形界面纳米涂层促进锂镍锰氧化物的锂离子存储
DOI：
10.1016/j.jcis.2020.02.112
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发表时间：
2020-06-15
影响因子：
9.9
通讯作者：
Zheng, Shiyou
中科院分区：
文献类型：
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作者：
Gao, Jinhuo;Yuan, Tao;Zheng, Shiyou
在这项工作中，共形的界面纳米涂层的策略，以提高锂离子存储性能的LiNi0.5Mn1.5O4（LNMO）。LNMO的稳定循环是通过La 2 O3涂层在室温和高温下实现的。制备了一系列La 2 O3包覆的LNMO复合材料，并系统地研究了其电化学行为。其中，2wt%La2O3包覆的LNMO阴极表现出最好的综合锂离子存储性能;例如，其在室温下500次循环后保持超过75%的容量保持率，并且在55 ℃的高温下以1C倍率循环50次后保持93%的容量保持率。此外，在循环过程中，改性的样品显示出比原始样品更稳定的平台电位。认为La 2 O3纳米涂层的引入可以有效抑制电极与电解液之间的副反应，从而保持电极材料的稳定结构，并降低循环过程中的极化。本工作为提高LNMO高电位正极的电化学稳定性提供了一种有效途径，为未来大规模应用高能量密度、长循环寿命的增强型锂离子电池奠定了基础。(C)2020爱思唯尔公司All rights reserved.
In this work, a conformally interfacial nanocoating strategy is introduced to enhance the lithium ion storage performance of LiNi0.5Mn1.5O4 (LNMO). Stable cycling of LNMO is achieved through La2O3 coating at both room and elevated temperatures. A series of La2O3-coated LNMO composites with various coating contents ranging from 0 to 3 wt% is prepared, and their electrochemical behaviors are systematically investigated. Among them, the 2 wt% La2O3-coated LNMO cathode presents the best comprehensive lithium ion storage performance; for instance, it retains more than 75% capacity retention after 500 cycles at room temperature and 93% capacity retention after 50 cycles at an elevated temperature of 55 degrees C with 1C rate. Moreover, the modified samples show more stable plateau potential than the pristine one during the cycling process. It is believed that the introduction of the La2O3 nanocoating layer can effectively suppress side reactions between electrode and electrolyte, thus maintaining stable structure of electrode material and reducing polarization during cycling. Our work provides an effective approach to improve the electrochemical stability of LNMO high-potential cathode for future large-scale applications of enhanced lithium ion batteries with high energy density and long cycle life. (C) 2020 Elsevier Inc. All rights reserved.