A long-life aqueous Fluoride-ion battery based on Water-in-salt electrolyte

Due to the high electronegativity and low weight, fluorine is an ideal element to design ion shuttle battery system. However, most fluoride-ion batteries apply solid electrolytes (SEs), it seems difficult to adopt water-based electrolyte in fluoride-ion batteries because of the narrow voltage window. In our work, we propose a method to apply KF water-in-salt electrolyte in Cu-Zn battery, construct a battery system based on the shuttle of fluoride-ion. Due to the new anode conversion mechanism, the discharge platform is improved to 1.9 V and the battery work steady for 1600 cycles. The battery takes the advantage of high conversion voltage of metal fluoride, while remains the Cu-Zn batteries' characteristics: low price, environmentally friendly etc. Our work not only avoid the generation of zinc dendrites, but also provide a new strategy to make Cu-Zn battery rechargeable.

Automated summary

In this study, a method of applying KF water-in-salt electrolyte in Cu-Zn battery was proposed, and a battery system based on the shuttle of fluoride-ion was constructed. Due to the new anode conversion mechanism, the discharge platform was improved to 1.9 V and the battery worked steadily for 1600 cycles. The battery takes advantage of the high conversion voltage of metal fluoride, while retaining the characteristics of Cu-Zn batteries such as low price and environmental friendliness. This work not only avoids the generation of zinc dendrites, but also provides a new strategy to make Cu-Zn battery rechargeable.