Battery (electricity)

Quantum mechanics

Engineering

Oxide

Electrochemistry

Metallurgy

Materials science

Cathode

Spinel

Power (physics)

Inorganic chemistry

Chemical engineering

Physical chemistry

Thermodynamics

Physics

Nanotechnology

Organic chemistry

Specific energy

Manganese

Energy storage

Aqueous solution

Chemistry

Electrode

Aluminium

Electrolyte

Nature Communications

Aluminum is a naturally abundant, trivalent charge carrier with high theoretical specific capacity and volumetric energy density, rendering aluminum-ion batteries a technology of choice for future large-scale energy storage. However, the frequent collapse of the host structure of the cathode materials and sluggish kinetics of aluminum ion diffusion have thus far hampered the realization of practical battery devices. Here, we synthesize Al x MnO 2 · n H 2 O by an in-situ electrochemical transformation reaction to be used as a cathode material for an aluminum-ion battery with a configuration of Al/Al(OTF) 3 -H 2 O/Al x MnO 2 · n H 2 O. This cell is not only based on aqueous electrolyte chemistry but also delivers a high specific capacity of 467 mAh g −1 and a record high energy density of 481 Wh kg −1 . The high safety of aqueous electrolyte, facile cell assembly and the low cost of materials suggest that this aqueous aluminum-ion battery holds promise for large-scale energy applications.

Electrochemically activated spinel manganese oxide for rechargeable aqueous aluminum battery