Electrochemical effects of annealing on atomic layer deposited Al2O3 coatings on LiNi0.5Mn0.3Co0.2O2
Journal of Power Sources(2017)
摘要
This study investigated the annealing of atomic layer deposited (ALD) Al2O3 coated onto Li-ion battery cathodes to enhance their electrochemical properties. LiNi0.5Mn0.3Co0.2O2 (NMC) cathode powders were coated with 5 ALD cycles at 100 °C, annealed between 300 and 700 °C, cast into electrode sheets and assembled into coin cells. Cells were characterized using charge-discharge cycling, electrochemical impedance spectroscopy, pre-casting and postmortem X-ray photoelectron spectroscopy, and charge endpoint slippage measurement. Diffusion of Al into bulk NMC was observable at ≥500 °C, and extent of diffusion increased with increasing temperature. Un-annealed ALD-coated cathodes showed exceptional capacity retention at high charge-discharge rates, while annealed cells showed recovery of initial charge capacity lost upon ALD coating. High quantities of LiF forming surface species were detected in cells annealed at 500 °C. This study approaches post-deposition annealing as a parameter that may be used to explore the electrochemical properties of ALD-coated battery cathodes.
更多查看译文
关键词
Atomic layer deposition,Diffusion,Aluminum oxide,Cathode,Annealing,Charge slippage
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要