A modified-electrochemical impedance spectroscopy-based multi-time-scale fractional-order model for lithium-ion batteries

•A MEIS-based multi-time-scale FOM to capture LIB dynamics in time-frequency domains.•The proposed MEIS accurately characterizes LIB internal dynamics in multi-time-scales.•The developed MEIS-based FOM significantly boosts the modeling accuracy by above 44%.•The proposed modeling methodology is independent of material chemistry and is generic.•Reveal the structural composition of the time-domain 1s impedance for the first time. The accurate prediction of battery dynamics in short and long time scales is essential for advanced battery management and precise systems simulation. A modified-electrochemical impedance spectroscopy-based multi-time-scale fractional-order model is thus proposed to reproduce battery dynamic behaviors both in time and frequency domains. It is first found that the conventional measurement electrochemical impedance spectroscopy (EIS) is pseudo-EIS due to the relatively high open-circuit-voltage variation. The modified EIS is developed to accurately characterize battery internal dynamics in short and long time scales. Noticeably, there is no perfect straight line in the modified EIS at low frequency, and a parallel circuit involving the fractional-order element and resistance is thus adopted to capture battery low-frequency dynamics. Model simulation results show excellent agreement with the experimental data under different dynamic conditions in multi-time-scales, where the maximum relative error is below 0.86%. Model comparison confirms that the proposed model can achieve a higher fidelity. Model validation with three battery chemistries indicates that the proposed modeling methodology showcases good adaptability. Ultimately, the structural composition of the time-domain 1s impedance is theoretically revealed using the proposed model for the first time, allowing to develop the approximate relationship of time-frequency-domain impedances. [Display omitted]