The high-nickel cathode material of LiNi 0.8 Co 0.15 Al 0.05 O 2 (LNCA) has a prospective application for lithium-ion batteries due to the high capacity and low cost. However, the side reaction between the electrolyte and the electrode seriously affects the cycling stability of lithium-ion batteries. In this work, Ni 2+ preoxidation and the optimization of calcination temperature were carried out to reduce the cation mixing of LNCA, and solid-phase Al-doping improved the uniformity of element distribution and the orderliness of the layered structure. In addition, the surface of LNCA was homogeneously modified with ZnO coating by a facile wet-chemical route. Compared to the pristine LNCA, the optimized ZnO-coated LNCA showed excellent electrochemical performance with the first discharge-specific capacity of 187.5 mA h g −1 , and the capacity retention of 91.3% at 0.2C after 100 cycles. The experiment demonstrated that the improved electrochemical performance of ZnO-coated LNCA is assigned to the surface coating of ZnO which protects LNCA from being corroded by the electrolyte during cycling. Graphical abstract

中文翻译：

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ZnO涂层改善高镍正极材料的长期循环性能

LiNi 0.8 Co 0.15 Al 0.05 O 2（LNCA）的高镍阴极材料因其高容量和低成本而有望在锂离子电池中应用。然而，电解质和电极之间的副反应严重影响锂离子电池的循环稳定性。在这项工作中，进行了Ni 2+预氧化和优化煅烧温度以减少LNCA的阳离子混合，固相Al掺杂改善了元素分布的均匀性和层状结构的有序性。另外，通过简便的湿化学路线，用ZnO涂层对LNCA的表面进行了均匀的改性。与原始LNCA相比，经过优化的ZnO涂层LNCA具有出色的电化学性能，其首次放电比容量为187.5 mA h g -1，100次循环后，在0.2C下的容量保持率为91.3％。实验表明，将ZnO涂层LNCA的电化学性能提高归因于ZnO的表面涂层，该涂层可保护LNCA免受循环过程中电解质的腐蚀。图形概要