Engineering Ternary Deep Eutectic Solvents for Stabilizing Zinc Anodes and Eutectogel Electrolytes in Zinc-Ion Batteries

Zinc-ion batteries (ZIBs) offer intrinsic safety, cost-effectiveness, and environmental sustainability, making them highly promising for next-generation energy-storage applications. However, the severe side reactions on the Zn anode hindered their practical utilization. Herein, we designed a ternary deep eutectic solvent (TDES) to stabilize the fabrication of zinc anodes while also utilizing it for the synthesis of eutectogel electrolytes. In contrast to conventional aqueous electrolytes, TDES facilitates the easy in situ formation of a CuZn4 alloy phase at the electrode interface through electrochemical deposition, enabling the successful fabrication of stabilized Zn@CuZn4 anode. Moreover, the eutectogel material obtained by introducing zwitterionic polymers into TDES can also be successfully used as an electrolyte for ZIB systems. The full-cell configuration using the Zn@CuZn4 anode paired with the eutectogel electrolyte demonstrates improved electrochemical performance compared to traditional zinc anode-based ZIB systems. The findings of this study highlight the significant potential of DES in optimizing ZIB systems.