High-Performance Layered Ni-Rich Cathode Materials Enabled by Stress-Resistant Nanosheets

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Layered O3-type transition metal oxides are key for high-energy-density lithium-ion batteries.
• Challenges include structural instability during delithiation and slow kinetics at full lithiation.

Purpose of the Study:

• To develop a novel synthesis approach for Ni-rich cathode materials with improved structural integrity and ion transport.
• To enhance the electrochemical performance and cycling stability of lithium-ion batteries.

Main Methods:

• Facile synthesis of secondary particles with aligned nanosheet primary grains.
• Characterization of structural evolution and electrochemical properties.
• Testing of a LiNi0.75Co0.14Mn0.11O2 cathode in a full cell with a graphite anode.

Main Results:

• Aligned nanosheet grains reduce internal stress and facilitate Li+ transport, preventing particle cracking.
• The synthesized Ni-rich cathode achieved a high reversible capacity of 206 mAh g-1.
• Demonstrated ultrahigh cycling stability with 98% capacity retention over 500 cycles.

Conclusions:

• The nanosheet grain alignment strategy effectively addresses structural instability and kinetic limitations in Ni-rich cathodes.
• This approach offers a promising pathway for developing next-generation high-energy-density and long-lasting lithium-ion batteries.