Reaction kinetics in rechargeable zinc-ion batteries

Rechargeable zinc-ion batteries (ZIBs) hold great potential for energy storage applications due to their cost-effectiveness, high safety, and high theoretical capacity. However, divalent zinc ions suffer from strong electrostatic interaction with their host materials during the charge/discharge process, resulting in the sluggish reaction kinetics. Improving the reaction kinetics of ZIBs is thereby of great significance to boost the electrochemical performance. Herein, we provide a comprehensive review on the energy storage mechanisms in ZIBs within the context of reaction kinetics including ion-diffusion coefficients, pseudocapacitive behaviors, theoretically computational Zn-ion migration paths and energy barriers, as well as ion transference in electrolyte and anode. Moreover, the advanced electrochemical measurements and theoretical calculation techniques for characterizing the kinetic parameters are also introduced. This review elucidates the correlations between and among electrode/electrolyte characters, reaction kinetics, reaction mechanisms, and electrochemical performance of ZIBs, and includes a perspective to highlight the challenges and promises in improving the performance of battery materials toward enhancing the reaction process kinetics, which can offer deep insights into the charge-storage process of ZIBs and provide valuable guides for the future design of fast-kinetics ZIBs.