The P2D model for a lithium-ion cell with particle radius distribution of the active materials

The assumption of constant electrode particle radius used in the classic pseudo two-dimensional model cannot meet the requirements for simulation accuracy. This work introduces the electrode particle radius distribution while maintaining the homogenization characteristics of the pseudo two-dimensional model, thereby improving simulation accuracy. The theoretical method of introducing electrode particle radius distribution into the pseudo two-dimensional model was mathematically derived, as well as the correction method for the specific surface area of electrode particles after introducing the electrode particle radius distribution. Finally, simulation verification was carried out on the pseudo-two-dimensional model without and with expanded electrode particle radius distribution based on experimental data. The results indicate that this method can more accurately simulate the polarization changes inside the battery, especially for the simulation of relaxation processes, with higher simulation accuracy.