Strengthening the interfacial stability of single-crystal LiNi_0.88Co_0.09Mn_0.03O₂ cathode with multiple-function...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Ni-rich layered cathode materials (LiNi$_{x}$Co$_{y}$Mn$_{1-x-y}$O$_{2}$, NCM) face structural instability due to interfacial issues, hindering commercialization.
• Addressing these drawbacks is crucial for developing advanced lithium-ion batteries.

Purpose of the Study:

• To propose a novel surface modification strategy for Ni-rich NCM using cerium (Ce) doping and in-situ coating.
• To enhance the structural stability and electrochemical performance of LiNi$_{0.88}$Co$_{0.09}$Mn$_{0.03}$O$_{2}$ (NCM).

Main Methods:

• Single crystal structure-based surface modification.
• In-situ construction of a Li$_{x}$CeO$_{2}$ coating layer and Ce surface doping.
• Comprehensive electrochemical testing and analysis.

Main Results:

• Ce-O bonding stabilized the oxygen framework, inhibiting lattice oxygen evolution and enhancing conductivity.
• The Li$_{x}$CeO$_{2}$ coating alleviated surface side reactions and reduced electrode polarization.
• The modified NCM@Ce material showed a high initial discharge capacity (196.3 mAh g$^{-1}$) and 79.7% capacity retention after 200 cycles.

Conclusions:

• The surface modification effectively suppresses the H2-H3 phase transition and improves conductivity.
• The Ce-modified NCM cathode exhibits superior electrochemical performance and high energy density (574.3 Wh kg$^{-1}$), making it promising for next-generation batteries.