Towards High‐Voltage Aqueous Metal‐Ion Batteries Beyond 1.5 V: The Zinc/Zinc Hexacyanoferrate System

A new aqueous zinc-ion battery based on a zinc anode and a zinc hexacyanoferrate cathode is demonstrated. It relies on two reversible electrochemical reactions: zinc deposition/dissolution at the anode side and Zn2+ intercalation/extraction at the cathode side. Its average operating voltage is as high as 1.7 V.