Core-Multishell-Structured Digital-Gradient Cathode Materials with Enhanced Mechanical and Electrochemical Durability

Area of Science:

• Materials Science
• Electrochemistry
• Chemical Engineering

Background:

• Ni-rich cathode materials offer high energy density but suffer from poor structural and thermal stability, limiting their practical application.
• Current manufacturing methods for concentration-gradient materials are not conducive to large-scale production.

Purpose of the Study:

• To develop a scalable manufacturing process for core-multishell Ni-rich cathode materials.
• To investigate the correlation between particle mechanical properties and electrochemical performance.

Main Methods:

• A digital-gradient cascade coprecipitation process was employed to synthesize core-multishell cathode materials.
• Mechanical properties (breaking force, elasticity) of particles were measured using a statistical approach.
• Electrochemical cyclability, rate performance, and thermal stability were evaluated.

Main Results:

• Core-multishell materials exhibited improved cycle life, rate performance, and thermal stability compared to homogeneous Ni-rich counterparts.
• The digital-gradient process enhanced productivity and quality consistency.
• A positive correlation was found between particle breaking force, surface stability, and electrochemical durability.

Conclusions:

• Heterogeneous particle engineering via core-multishell structures is a viable strategy for achieving long life and high thermal stability in Ni-rich cathode materials.
• The digital-gradient cascade coprecipitation process is suitable for large-scale manufacturing.
• Mechanical properties are critical indicators for predicting the electrochemical cyclability of cathode particles.