Rational design of an organic–anionic electrolyte additive for zinc-ion batteries

Abstract

Zinc-ion batteries (ZIBs) have drawn a lot of attention due to their high safety and cheap cost. Nevertheless, Zn dendrite growth and the hydrogen evolution reaction have prevented the large-scale application of ZIBs. To address these issues, herein, an acrylamide (AM) and sodium p-aminobenzenesulfonate (SABS) composite electrolyte additive has been added into ZIBs. The theoretical calculations reveal that SABS can not only access the solvation shell of Zn²⁺ ions, but also diminish the interaction of H₂O molecules. The combination of AM and SABS can attenuate the formation of Zn dendrites. The electrochemical tests manifest that the Zn‖Zn battery using the AM and SABS electrolyte additive can be stably charged and discharged for over 1600 h at 2 mA cm⁻², which is much longer than that of the Zn‖Zn battery using pure electrolyte. Moreover, the Zn‖KMO battery using the AM and SABS electrolyte additive exhibits a 90.6% capacity retention after 1200 cycles at 1 A g⁻¹. Given the stellar modification effect and the simple preparation method, this work can provide notable guidance for improving the cycle life of ZIBs.