Local Cation-Ordered Superlattice Stabilizing Ni-Rich Single-Crystalline Cathodes.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Ni-rich single-crystalline cathodes offer high energy density but suffer from structural heterogeneity due to high sintering temperatures.
• This heterogeneity leads to poor electrochemical performance and limits practical applications of advanced lithium-ion batteries.

Purpose of the Study:

• To develop a novel presintering strategy for synthesizing cation-ordered single-crystalline LiNi0.83Co0.12Mn0.05O2 (S-NCM83) with improved structural stability and electrochemical properties.
• To address the intrinsic lattice chemical heterogeneity and defect formation in Ni-rich single-crystalline cathode materials.

Main Methods:

• A lithium-deficient presintering strategy was employed to synthesize S-NCM83.
• Characterization of the material's structural integrity, cation ordering, and Li+ migration pathways.
• Electrochemical testing was performed to evaluate cycling stability and rate performance at various temperatures.

Main Results:

• The proposed strategy successfully minimized lattice chemical heterogeneity and defect formation, creating a cation-ordered percolation network.
• The S-NCM83 material exhibited enhanced structural stability, reduced Li+ migration energy barriers, and stabilized diffusion pathways.
• Exceptional rate performance (206 mAh g-1 at 0.1 C, 170 mAh g-1 at 5 C) and improved cycling stability were achieved without surface coatings or doping.

Conclusions:

• The lithium-deficient presintering strategy is a universal approach to overcome structural instability in single-crystalline cathodes.
• This method enables simplified and scalable production of long-life, high-energy lithium-ion batteries.
• The findings pave the way for next-generation battery technologies with enhanced performance and durability.