The Development of a 3D Pore-Scale Lattice Boltzmann Model for 3D Microstructure Modeling and Design of Li-Ion Battery Electrodes

Abstract

Herein, the development of a 3D pore-scale lattice Boltzmann (LB) model for simulating the transport processes and electrochemical performance of the porous electrodes in Li-ion batteries is reported. The model captures the transport of ions, electrons, and liquid electrolyte species, coupled with the electrochemical reactions at the interface between the active material and the liquid electrolyte with complex boundary conditions. The model-predicted discharge curves of a realistic nickel–manganese–cobalt battery electrode are shown to be in good agreement with the experimental measurement on the same electrode, demonstrating the validity of the model prediction. The LB model is then applied to simulate a series of electrode structures generated using the discrete-element method, to understand the effects of particle size and distribution, porosity, pore size distribution, surface area, and tortuosity on the performance of the electrode. It is revealed that surface area and pore size distribution are the dominant factors for the performance, and electrodes with structured patterns are beneficial for achieving uniform local distribution of Li and current densities within the electrode. The LB model provides insightful understanding of spatial distribution of Li and local phenomenon in 3D electrode structures, and can be a useful tool for designing next-generation battery electrodes.