Battery (electricity)

Quantum mechanics

Engineering

Electrochemistry

Metallurgy

Materials science

Potassium hydroxide

Power (physics)

Alkaline battery

Inorganic chemistry

Chemical engineering

Physical chemistry

Thermodynamics

Physics

Energy storage

Composite material

Corrosion

Chemistry

Electrode

Anode

Aluminium

Electrolyte

Energy storage materials

Alkaline aluminum-air batteries show great potential for energy storage applications because of their high theoretical energy density and low cost. However, they are suffering from severe anodic self-corrosion and the gelation of electrolyte which greatly reduce the practical energy density and shelf life. Herein, we firstly construct an efficient high-energy alkaline Al-air battery based on high-concentration potassium acetate-potassium hydroxide electrolyte and prototype optimization. The self-corrosion of Al anode is greatly suppressed owing to the special hydrate structure in such electrolyte. The Al-air battery with optimum electrolyte demonstrates remarkable increased discharge capacity of 2324 mAh g−1, and the constructed miniaturized Al-air battery enables an outstanding system energy density of 436.1 ​Wh kg−1 (compared with 85.8 ​Wh kg−1 of normal electrolyte) after integrating a discharge product removing system. This work opens up a new direction for the practical realization of high-energy, low-cost, and high-efficiency alkaline Al-air battery and other aqueous metal-air batteries.

Hybrid high-concentration electrolyte significantly strengthens the practicability of alkaline aluminum-air battery