The dynamic process of ions transport in electrochromic WO₃ film is usually studied by electrochemical impedance spectroscopy. However, the detailed features are hidden since the ions insertion into WO₃ is a very complex process including structural deformation and phase transformations. Chronopotentiometry is an electrochemical characterization method that measures the response potential of a system under an imposed current. Compared to other dynamic characterization methods (impedance spectroscopy and CV), it allows direct access to the voltage contributions in different states of the solution-electrode system and has frequently been used to investigate kinetic effects such as adsorption and transport phenomena near electrode surface. In this study, chronopotentiometry is creatively applied to study ion transport kinetics and control ions insertion behavior in electrochromic WO₃ film. The results suggest that a large ions insertion flux at the interface of WO₃/electrolyte could broaden ions transport channels due to the fierce lattice expansion during Li⁺ions insertion process, which further improves the ions transportation kinetics and gifts a fast switching speed of optical performance. However, the repeating ions insertion/extraction behaviors at the interface of WO₃/electrolyte for the long-term cycle process can reduce the size of WO₃ grains as a “ball mill effect”. Especially, a large ions transport flux can aggravate the “ball mill effect”. Consequently, the structure of the WO₃ film becomes very dense, which is unfavorable for ions transport and electrolyte permeation. This dense structure also leads to an irreversible accumulation of Li⁺ ions and Li_xWO₃ in the WO₃ host structure, resulting in a decay of optical modulation ability and electrochromic activity. This work offers an efficient method to analyze ion transport kinetics in intercalation materials and a new understanding of the relationship between ion transport behavior and cyclic stability of electrochromic materials.