Improving the electrochemical cycle stability of LiNi0.8Co0.1Mn0.1O2 via Al(H2PO4)3 treatment on its precursor

• Published in: Materials letters Vol. 364; p. 136278
• Main Authors: Li, Shidong, Dai, Shuhan, Guo, Xingbo, Wang, Wenhui, Yang, Guiling
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-06-2024
• Subjects: Al(H2PO4)3; Al3+ doping; Deposition; Interfaces; Li3PO4-LiAlO2 coating; Ni-rich layered cathode; Interfaces; Al(H2PO4)3; Ni-rich layered cathode; Al3+ doping; Li3PO4-LiAlO2 coating; Deposition
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2024.136278

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•Al(H2PO4)3 flakes are deposited on Ni0.8Co0.1Mn0.1(OH)2 by evaporating the solvent.•Al3+ doping and Li3PO4-LiAlO2 coating for NCM811 are synergistically achieved.•The electrochemical cycle stability of the modified NCM811 is greatly improved.
Ni-rich layered transition-metal oxides are important cathodes for lithium-ion batteries (LIBs). Unfortunately, they still suffer from capacity fading arising from structure transformation and side reactions. Cation doping and surface coating with a protective layer can alleviate the problem. Herein, a synergistic strategy of Al3+ doping near the surface and Li3PO4-LiAlO2 coating is adopted to modify LiNi0.8Co0.1Mn0.1O2 (NCM811), and it is carried out by using a simple Al(H2PO4)3 wet deposition method on its precursor. Structure and surface analysis show that Li3PO4-LiAlO2 is formed on the NCM surface and some Al3+ ions enter the near-surface lattice of cathode particles. Compared to NCM811, the modified-NCM811 exhibits slower impedance growth and better capacity retention (from 55.55 % to 75.09 % after 100 cycles) during cycling, which shows the strategy can effectively stabilize the interface and crystal structure.