Modeling the capacity degradation of LiFePO4/graphite batteries based on stress coupling analysis

► Battery capacity degradation is affected by temperature, discharge rate, EODV, charge rate and EOCV. These factors are generally coupled. ► The coupling intensity is related to stress levels. There exists a critical stress level at which the coupling can be neglected. When the stress level exceeds the critical value, the coupling aggravates battery degradation exponentially. ► The capacity degradation model achieves an error less than 15% when the cycling goes into the stable decay period, and the error converges gradually as the cycling continues.