title: Improvement of electrochemical performance of nickel rich LiNi0.6Co0.2Mn0.2O2 cathode active material by ultrathin TiO2 coating.
abstract: LiNi0.6Co0.2Mn0.2O2 cathode material has been surface-modified by coating with ultrathin TiO2via atomic layer deposition (ALD) technology to improve the electrochemical performance of LiNi0.6Co0.2Mn0.2O2 cathodes for lithium ion batteries. Within the cut-off voltage of 2.5-4.3 V, the coated sample delivers an initial discharge capacity of 187.7 mA h g(-1) at 0.1 C and with a capacity retention about 85.9% after 100 cycles at 1 C, which provides a significant improvement in terms of discharge capacity and cyclability, as compared with those of the bare one. Such enhanced electrochemical performance of the coated sample is ascribed to its high-quality ultrathin coating of amorphous TiO2, which can protect the active material from HF attack, withstand the dissolution of metal ions in the electrode and favor the lithium diffusion of oxide as proved by electrochemical impedance spectroscopy (EIS) tests. TiO2 coating via the ALD process provides a potential approach for battery factories to surface-modify Ni-rich electrode materials so as to realize improvements in electrochemical performance.
authors.affiliation: National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210093, China. yftang@nju.edu.cn.
authors.forename: CanCan
authors.initials: C
authors.lastname: Qin
authors.forename: JiaLi
authors.initials: J
authors.lastname: Cao
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: GaoLe
authors.initials: G
authors.lastname: Dai
authors.forename: TongFu
authors.initials: T
authors.lastname: Wu
authors.forename: Yanbin
authors.initials: Y
authors.lastname: Chen
authors.forename: YueFeng
authors.initials: Y
authors.lastname: Tang
authors.forename: AiDong
authors.initials: A
authors.lastname: Li
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Chen