Classification of spatio‐temporal patterns in charging and discharging of Li‐ion batteries

Abstract

AbstractWe classify the dynamic patterns that emerge in charging or discharging of Li‐ion batteries, under galvanostatic conditions, using simulations of the two‐phase one‐dimensional (1D) porous electrode model. This work examines the effect of the exchange current function, R0(X), which expresses the nature of kinetics. This extends our previous study with R0 = 1 where the same pattern emerges in charging or discharging, whether as a homogeneous or a step‐wise process made of multiple symmetry breaking events. With commonly‐used asymmetric R0(X), the emerging patterns may be one of the two above or as fronts that follow single SB event and the lithiation/delithiation behaviors are different. These effects are clear when parameters are uniform; nonuniformity leads to noise that mask the behavior. The full four‐variable model exhibits SB, even in absence of noise, since the liquid potential gradient () works like a perturbation. This similarity allows us to derive approximations to the full model behavior.