Noncovalent Interactions‐Driven Self‐Assembly of Polyanionic Additive for Long Anti‐Calendar Aging and High‐Rate Zinc Metal Batteries

Abstract

Abstract Zinc anodes of zinc metal batteries suffer from unsatisfactory plating/striping reversibility due to interfacial parasitic reactions and poor Zn2+ mass transfer kinetics. Herein, methoxy polyethylene glycol‐phosphate (mPEG‐P) is introduced as an electrolyte additive to achieve long anti‐calendar aging and high‐rate capabilities. The polyanionic of mPEG‐P self‐assembles via noncovalent‐interactions on electrode surface to form polyether‐based cation channels and in situ organic–inorganic hybrid solid electrolyte interface layer, which ensure rapid Zn2+ mass transfer and suppresses interfacial parasitic reactions, realizing outstanding cycling/calendar aging stability. As a result, the Zn//Zn symmetric cells with mPEG‐P present long lifespans over 9000 and 2500 cycles at ultrahigh current densities of 120 and 200 mA cm−2, respectively. Besides, the coulombic efficiency (CE) of the Zn//Cu cell with mPEG‐P additive (88.21%) is much higher than that of the cell (36.4%) at the initial cycle after the 15‐day calendar aging treatment, presenting excellent anti‐static corrosion performance. Furthermore, after 20‐day aging, the Zn//MnO2 cell exhibits a superior capacity retention of 89% compared with that of the cell without mPEG‐P (28%) after 150 cycles. This study provides a promising avenue for boosting the development of high efficiency and durable metallic zinc based stationary energy storage system.

Keywords

• aqueous Zn‐ion batteries
• calendar aging
• electrolyte additive
• ion transfer
• self‐assemble