Lithium-rich layered nickel–manganese oxides as high-performance cathode materials: the effects of composition and PEG on performance

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• 作者：Meifeng Chen ; Wan Ren ; Yijia Shao ; Ting Shu ; Lina Liu ; Shijun Liao
• 关键词：Polyethylene glycol ; Lithium ; rich layered oxide ; Cathode materials ; Lithium ; ion battery
• 刊名：Ionics
• 出版年：2016
• 出版时间：November 2016
• 年：2016
• 卷：22
• 期：11
• 页码：2067-2073
• 全文大小：861 KB
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Chemistry
  Electrochemistry
  Materials Science
  Physical Chemistry
  Condensed Matter
  Renewable Energy Sources
  Electrical Power Generation and Transmission
  
• 出版者：Springer Berlin / Heidelberg
• ISSN：1862-0760
• 卷排序：22

文摘

Lithium-rich layered nickel–manganese oxide (LRL-NMO) as a cathode material for rechargeable lithium-ion batteries was successfully prepared using an oxalic acid co-precipitation method, with polyethylene glycol (PEG1000) as an additive. The effects of the Ni/Mn ratio and of PEG on the phase purity, morphology, and electrochemical performance of LRL-NMO were investigated with X-ray diffraction, scanning electron microscope, electrochemical impedance spectroscopy, and charge/discharge testing. Li[Li_0.167Ni_0.25Mn_0.580]O₂ delivered the best electrochemical performance among the various Li[Li_1/3−2x/3Ni_xMn_2/3−x/3]O₂ (0 < x < 0.5) materials. Furthermore, the sample to which an appropriate amount of PEG had been added showed much smaller and more uniform particle size, higher discharge capacity and energy density, better cycling stability, and lower resistance. The material prepared by adding 9 wt% PEG exhibited high discharge capacity and stability; after 100 cycles at 2 C, it still delivered a discharge capacity of 125.6 mAh g−1, which was 50 % higher than that of a sample prepared without PEG.