Minimize the Electrode Concentration Polarization for High-Power Lithium Batteries

High-loading electrode is a prerequisite for achieving high energy density in industrial applications of lithium-ion batteries. However, an increased loading leads to elevated battery polarization and reduced battery power density, which presents a significant technical bottleneck in the industry. The present study focuses on designing a rapid electrolyte diffusion pathway to diminish lithium concentration polarization for the high-loading LiNi_0.83Mn_0.12Co_0.05O₂ (NMC83) electrode by employing two layers of NMC83 materials with different sizes. This innovative architecture demonstrates exceptional rate performance even under challenging conditions with high-loading and high-rate. Additionally, the interrelationships between electrode structure, process route, porosity, and optimal thickness ratio between layers are discussed, providing valuable guidance for industrial promotion and application. The designed L-Dry-S electrode structure (coating large particles first and then small particles) effectively mitigates concentration polarization in the thick electrode, which is attributed to the fast electrolyte diffusion channel and the differential reaction speeds of NMC83 particles with varying sizes. The knowledge from this work is broadly applicable to other material systems.