Decoupled measurement and modeling of interface reaction kinetics of ion-intercalation battery electrodes

•The reaction and diffusion kinetics of active particles are decoupled via time-resolved potential measurements with an interval of 1 ms.•The classical Butler-Volmer equation is demonstrated to deviate from the actual relation between current density, overpotential, and Li+ concentration.•An interface ion-intercalation model is developed which enables accurate prediction of charging/discharging at both particle and electrode scales for various active materials.•The kinetic limitation processes from single particles to composite electrodes with specific areal capacities are systematically revealed, promoting rational designs of high-power batteries.