Battery (electricity)

Quantum mechanics

Engineering

Oxide

Electrochemistry

Metallurgy

Materials science

Cathode

Power (physics)

Inorganic chemistry

Chemical engineering

Vanadium

Zinc

Dissolution

Physical chemistry

Cathodic protection

Physics

Energy storage

Aqueous solution

Galvanic anode

Corrosion

Chemistry

Electrode

Anode

Electrolyte

Vanadium oxide

Nature Communications

Aqueous zinc ion batteries are receiving increasing attention for large-scale energy storage systems owing to their attractive features with respect to safety, cost, and scalability. Although vanadium oxides with various compositions have been demonstrated to store zinc ions reversibly, their limited cyclability especially at low current densities and their poor calendar life impede their widespread practical adoption. Herein, we reveal that the electrochemically inactive zinc pyrovanadate (ZVO) phase formed on the cathode surface is the main cause of the limited sustainability. Moreover, the formation of ZVO is closely related to the corrosion of the zinc metal counter electrode by perturbing the pH of the electrolyte. Thus, the dissolution of VO 2 (OH) 2 − , the source of the vanadium in the ZVO, is no longer prevented. The proposed amalgamated Zn anode improves the cyclability drastically by blocking the corrosion at the anode, verifying the importance of pH control and the interplay between both electrodes.

Corrosion as the origin of limited lifetime of vanadium oxide-based aqueous zinc ion batteries