A particle packing electrode model for microstructure optimization of lithium-ion batteries

Abstract

The microstructure of porous electrodes has a significant impact on the performance of lithium-ion batteries (LIBs). The critical challenge in theoretical research of porous electrodes is to construct an electrode model that properly describes its microstructure while ensuring solving efficiency. In this work, a particle packing electrode (PPE) model is used to analyze the charging dynamics of LIBs, which is constructed based on the randomness distribution of the active materials. After accurately predicting the experimental data, the PPE model illustrates two key factors governing the C-rate performance: The C-rate performance depends on the Li+ transfer in active material at low C-rate and depends on Li+ transfer in the electrolyte at high C-rate. By optimizing the uniformity of the particle size and the orderliness of the pore structure, LIBs achieve improved performance. This model offers novel possibilities for designing and optimizing electrode microstructures of LIBs.