Regulating interfacial kinetics boosts the durable A h-level zinc-ion batteries†

Abstract

Aqueous zinc-ion batteries (AZIBs) with low cost and inherent safety have been viewed as crucial candidates for energy storage systems. However, their commercialization is hindered by interfacial instability, including the growth of dendritic zinc (Zn) and passivation on electrodes from H₂O-derived parasitic side-reactions. Herein, a type of adjustable-kinetics electrolyte containing tetramethylene glycol with rich ethers and hydroxyl groups as a co-solvent is designed to stabilize the Zn anode and achieve highly reversible and durable AZIBs. Lowering interfacial kinetics can effectively minimize the variations in faradaic current density, refining nuclei and homogenizing the electrodeposition of Zn metal. Moreover, it can be involved in the solvation reconstruction of Zn²⁺ to weaken the side reaction and passivation on the cathode. Consequently, Zn|Zn symmetrical cells with this low-kinetics electrolyte show high reversibility and an exceptional 7000-hour lifespan at 1.0 mA cm⁻². Moreover, the NH₄V₄O₁₀|Zn pouch cell exhibits a capacity of 110 mA h and maintains stable cyclic stability for 450 cycles without capacity degradation. As a proof of concept, the 1.3-A h NH₄V₄O₁₀|Zn AZIB lasts for more than 25 days in deep charge/discharge operation. In this study, low interfacial kinetics is confirmed as a new perspective to accelerate the commercialization of AZIBs with a satisfactory lifespan.