Effect of Antisolvent Additives in Aqueous Zinc Sulfate Electrolytes for Zinc Metal Anodes: The Case of Acetonitrile

Abstract

Aqueous zinc-ion batteries (ZIBs) employing zinc metal anodes are gaining traction as batteries for moderate to long duration energy storage at scale. However, corrosion of the zinc metal anode through reaction with water limits battery efficiency. Much research in the past few years has focused on additives that decrease hydrogen evolution, but the precise mechanisms by which this takes place are often understudied and remain unclear. In this work, we study the role of an acetonitrile antisolvent additive in improving the performance of aqueous ZnSO 4 electrolytes using experimental and computational techniques. We demonstrate that acetonitrile actively modifies the interfacial chemistry during Zn metal plating, which results in improved performance of acetonitrile-containing electrolytes. Collectively, this work demonstrates the effectiveness of solvent additive systems in battery performance and durability and provides a new framework for future efforts to optimize ion transport and performance in ZIBs.

Unlocking the potential of cadmium plating chemistry for low-polarization, long-cycling, and ultrahigh-efficiency aqueous metal batteries

“…2g provides a comparison between the Zn and Cd in terms of plating efficiency and cycling time. Although Zn metal has realized high efficiencies (99.18–99.95%) and good cycling life (200–2200 hours) in asymmetrical batteries, it has to rely on the use of concentrated electrolytes, 7,39,42–44 functional additives, 45–48 or delicate surface treatments. 49,50 By contrast, Cd exhibits an extraordinary CE (99.93%) and cycling time (3243 hours) in a regular testing condition, which suggests a super low manufacturing cost.…”

Solvation Sheath Regulation to Induce Sulfide Solid–Electrolyte Interphase on Zn Metal Anode

“…Nevertheless, the regulation of bulk electrolyte properties requires large amount of additives. In comparison, additives that adsorb on Zn surface and modify the interface environment can be applied with much lower content . Besides, artificial layers such as Sn, Cu, ZnO, ZnS, and Zn­(TCNQ) 2 are constructed on Zn electrode surface to shield water molecules and homogenize Zn 2+ flux.…”