Method of Lines for flexible coupling of the Single Particle Model for Lithium-Ion Batteries demonstrated by thermal modelling

Abstract

Electrochemical models like the Pseudo-two-dimensional (P2D) model and the Single Particle Model (SPM) are widely used in the field of battery simulation. The SPM provides accurate results for small currents with low computational costs. However, commonly used solving strategies limit the applicability of the SPM to certain physical effects. This work introduces a universal solving strategy using Method of Lines (MOL) that allows the integration of several electrochemical and thermal effects without changing the basic mathematical model structure. The model can be easily extended, which was demonstrated by including thermal effects and dynamic diffusion coefficients. The MOL-SPM is compared to a P2D model and experimental data of galvanostatic discharges and a dynamic current profile. The MOL-SPM calculates up to 400 times faster than the P2D model for the dynamic current profile while producing a similar small model error with an RMSE difference of only 0.9 mV compared to the P2D model.