Nanomaterials (Sep 2020)

Protective Spinel Coating for Li<sub>1.17</sub>Ni<sub>0.17</sub>Mn<sub>0.50</sub>Co<sub>0.17</sub>O<sub>2</sub> Cathode for Li-Ion Batteries through Single-Source Precursor Approach

  • Andrey Shevtsov,
  • Haixiang Han,
  • Anatolii Morozov,
  • Jesse C. Carozza,
  • Aleksandra A. Savina,
  • Iaroslava Shakhova,
  • Nellie R. Khasanova,
  • Evgeny V. Antipov,
  • Evgeny V. Dikarev,
  • Artem M. Abakumov

DOI
https://doi.org/10.3390/nano10091870
Journal volume & issue
Vol. 10, no. 9
p. 1870

Abstract

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The Li1.17Ni0.17Mn0.50Co0.17O2 Li-rich NMC positive electrode (cathode) for lithium-ion batteries has been coated with nanocrystals of the LiMn1.5Co0.5O4 high-voltage spinel cathode material. The coating was applied through a single-source precursor approach by a deposition of the molecular precursor LiMn1.5Co0.5(thd)5 (thd = 2,2,6,6-tetramethyl-3,5-heptanedionate) dissolved in diethyl ether, followed by thermal decomposition at 400 °C inair resulting in a chemically homogeneous cubic spinel. The structure and chemical composition of the coatings, deposited on the model SiO2 spheres and Li-rich NMC crystallites, were analyzed using powder X-ray diffraction, electron diffraction, high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and energy-dispersive X-ray (EDX) mapping. The coated material containing 12 wt.% of spinel demonstrates a significantly improved first cycle Coulombic efficiency of 92% with a high first cycle discharge capacity of 290 mAhg−1. The coating also improves the capacity and voltage retention monitored over 25 galvanostatic charge–discharge cycles, although a complete suppression of the capacity and voltage fade is not achieved.

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