On the joint dynamics of potentials and currents in porous electrodes: Model reduction

Abstract

The dynamic behavior of potentials and currents in porous electrodes is crucial for optimizing the computational speed of lithium-ion battery models. Pseudo-two-dimensional (P2D) models, based on partial differential equations, offer insight but pose computational challenges. P2D equations are tackled with iterative algorithms, like the Newton or the shooting method. Yet, initiating the algorithm with random guesses for solid and electrolyte potentials can cause diverging ionic current values inside the electrolyte phase, increasing the computation time required to converge to the final solution. This study proposes a novel model order reduction using a galvanic pseudo-potential to prevent the occurrence of diverging currents. By sidestepping infinite values for ionic current inside the electrolyte phase, the method streamlines math and speeds up the shooting method used for solving battery model equations.