Achieving Highly Stable Zn Anode via Regulating the Solvation Sheath Structure of Electrolyte with a Maltodextrin Additive

Aqueous zinc-ion batteries (AZIBs) as a new category of energy storage system display a distinct prospect in achieving the aim of carbon neutrality on account of the features of desirable safety, abundant reserves, affordable cost, and low environmental impact. However, the Zn anode always suffers from water corrosion, interface side reactions, and dendritic growth, which greatly hinder its practical application in AZIBs. Herein, a simple and effective strategy is proposed to achieve stable Zn anode through using maltodextrin (MD) as an electrolyte additive. The MD additive is rich in polar functional groups, which can effectively enable the desolvation of Zn2+ in electrolytes by removing H2O molecules from the solvated {Zn(H2O)6}2+, inhibiting the occurrence of side reactions and dendritic growth. As a result, the Zn anode demonstrates long cycle-life (2100 h at 1 mA cm–2, 1 mAh cm–1, 1200 h at 2 mA cm–2, 2 mAh cm–1) and enhanced Coulombic efficiency [99.7% upon 600 cycles (1200 h) at 1 mA cm–2, 1 mAh cm–1]. In addition, a full cell with sodium vanadate as the cathode is assembled, which shows a high reversible capacity of 166.6 mAh g–1 over 1100 cycles at 2 A g–1. This exploration develops a promising alternative to achieve high-performance AZIBs using effective and low-cost electrolyte additives.