Boosting Zinc-Ion Batteries with Innovative Ternary Electrolyte for Enhanced Interfacial Electrochemistry and Temperature-Resilient Performance

The practical application of Zn-ion batteries (ZIBs) faces several challenges, particularly regarding poor reversibility and the reactivity of water in the electrolytes across a wide temperature range. Herein, this study presents the design of a ternary electrolyte with significant intermolecular interactions based on tetrahydrofurfuryl alcohol (THFA), H2O, and Zn(OTf)(2) to address these challenges from -40 to 60 C-degrees. The ether alcohol compound THFA effectively mitigates the side reactions about water, by disrupting and suppressing the reactivity of the dominant water-based clusters. Through experimental and theoretical investigations, the structural and mechanistic insights of ternary solvation clusters are uncovered. The hydrogen-bond-induced interactions of THFA facilitate the participation of OTf- in solvation clusters and bidentate chelation coordination with Zn2+ ensures the formation of lean-water solvation clusters. Furthermore, the interfacial electrochemistry on the Zn surface is also regulated to exhibit a preferential layer-by-layer (0 0 2) oriented deposition with a stable solid electrolyte interface (SEI). As a result, The Zn||VO2 battery using ternary electrolyte maintains a capacity of 237.5 mAh g(-1) with an 86.71% retention after 500 cycles at 60 C-degrees and 3 A g(-1), while it exhibits stable cycle even at -40 C-degrees over 200 cycles with almost no capacity decrease.