Atomic-scale tuned interface of nickel-rich cathode for enhanced electrochemical performance in lithium-ion batteries

Yongqiang Liu^1,2，Xin Wang²，Jiyu Cai²，Xiaoxiao Han²，Dongsheng Geng¹，Jianlin Li³，Xiangbo Meng²

1. Beijing Advanced Innovation Center for Materials Genome Engineering, Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, School of Materials Science and Engineering, University of Science and Technology Beijing2. Department of Mechanical Engineering, University of Arkansas3. Energy and Transportation Science Division, Oak Ridge National Laboratory

摘 要：The Ni-rich layered LiNi_0.6Mn_0.2Co_0.2O₂（NMC622） is one promising cathode for lithium-ion batteries（LIBs）, but suffers from poor cycling stability under high cutoff potentials. The performance degradation was reflected as capacity fading and voltage drop, having their roots in instable interface of NMC622.Aimed at improving interfacial stability, in this study, we deposited nanoscale ZrO₂ coatings conformally over NMC622 cathodes using atomic layer deposition（ALD）. We found that, under a high cutoff voltage（4.5 V）, the ALD ZrO₂ coatings evidently improved the performance of NMC622 cathode, showing better cyclability and higher sustainable capacity. In addition, the ALD coatings dramatically boosted the rate capability of NMC622. All these compelling performance results are ascribed to the atomic-scale tunable ZrO₂ coatings via ALD, which create stable interface and thereby inhibit unfavorable evolutions. In the study, we utilize a suite of characterization tools and various analyses to clarify the effects of ALD ZrO₂ coatings. This study will be helpful for improving the performance of nickel-rich cathodes via interfacial engineering using ALD.

关键词：