Highly Reversible Zn Metal Anode Securing by Functional Electrolyte Modulation

Abstract

AbstractThe stability of the Zn metal anode is significantly affected by the various parasitic reactions during plating/stripping. Here, sodium 4‐aminobenzenesulfonate (SABS) is a functional electrolyte additive to modulate the electrode/electrolyte interface to protect the Zn metal. An electrical double layer (EDL) reconstruction of the interface is affected by providing hydrogen bond sites through nitrogen and oxygen elements with lone pair electrons in SABS molecules. These strong hydrogen bonds not only limit the corrosion of free H2O molecules on the surface of Zn anode but also promote the desolvation process. Besides, the SABS can be further in situ decomposed into a solid electrode/electrolyte interface (SEI) layer to regulate the plating/stripping behavior of Zn2+. As a result, based on the synergism of organic–inorganic hybrid SEI layer and the EDL reconstruction, the Zn//Zn symmetric cells exceptionally survive lasting for 6500 hours at 1 mA cm−2 and 1 mAh cm−2, and over 900 cycles even at 40 mA cm−2 and 10 mAh cm−2. The Zn‐I2 full cell maintains excellent cycle stability of 92.4% after 20000 cycles. Remarkably, the pouch cell maintains a capacity retention of over 99.1% (63 mAh) for 820 cycles at 5 mA cm−2.