Multifunctional Electrolyte toward Long-Life Zinc-Ion Batteries: Synchronous Regulation of Solvation, Cathode and Anode Interfaces

Rechargeable aqueous zinc-ion batteries (ZIBs) are threatened by the cathode dissolution and anode corrosion/dendrites, resulting in poor reversibility. Here, a multifunctional electrolyte is developed to regulate the cathode, anode interface, and solvation by introducing a low-cost diethylene glycol monomethyl ether (DGME). The DGME can modulate the primary solvation sheath (PSS) of the hydrated Zn2+ and destroy the original hydrogen bond network of water, while the electric double layer (EDL) interface is reconstructed by the adsorption of DGME, which guides the uniform deposition of Zn2+ on the (002) crystal plane. Simultaneously, the DGME also effectively inhibits the dissolution of VO2 and enhances the reaction kinetics. As a proof of concept, the Zn//Cu cells deliver 2000 cycles with an ultrahigh coulombic efficiency (CE) of 99.6%. Additionally, the multifunctional electrolyte significantly improves the multiple performance of Zn//VO2 full cells. The low-cost and multifunctional electrolyte can be readily applied to ZIBs, demonstrating its practical versatility. In this study, the use of a low-cost diethylene glycol monomethyl ether as an effective electrolyte additive to optimize the cathode, anode/electrolyte interface, and the primary solvation structure is explored. This multifunctional electrolyte additive significantly achieves a long-life aqueous zinc-ion battery of Zn//VO2.image