Life Prediction Methods for Lithium-Ion Batteries Derived from a Fatigue Approach

A methodology for predicting the capacity loss of a battery under a complex current profile is provided. The prediction is based upon a set of elementary aging experiments, which are herein generated by a physics-based model featuring a surrogate battery, for which the source of aging is the growth of a solid-electrolyte interphase at the anode. Empirical correlations of the capacity loss as a function of the aging time and of the aging time as a function of the capacity loss are developed based on 12 dummy elementary aging experiments under different conditions of state of charge and current. Those correlations are used together with the relationship for loss accumulation over time or the Palmgren–Miner rule (both introduced in Part I) to predict the aging of a complex current profile. The prediction accuracy is assessed by a direct simulation of the complex profile by using the physics-based model featuring the surrogate battery.