Physics

Nanotechnology

Electrode

Organic chemistry

Potassium carbonate

Potassium

Anode

Endocrinology

Engineering

Physical chemistry

Power (physics)

Inorganic chemistry

Chemistry

Salt (chemistry)

Metallurgy

Materials science

Lithium (medication)

Layer (electronics)

Cathode

Metal

Battery (electricity)

Quantum mechanics

Electrolyte

Passivation

Chemical engineering

Electrochemistry

Medicine

Potassium-ion battery

Lithium vanadium phosphate battery

National Science Review

Electrolyte anions are critical for achieving high-voltage stable potassium-metal batteries (PMBs). However, the common anions cannot simultaneously prevent the formation of 'dead K' and the corrosion of Al current collector, resulting in poor cycling stability. Here, we demonstrate cyclic anion of hexafluoropropane-1,3-disulfonimide-based electrolytes that can mitigate the 'dead K' and remarkably enhance the high-voltage stability of PMBs. Particularly, even using low salt concentration (0.8 M) and additive-free carbonate-based electrolytes, the PMBs with a high-voltage polyanion cathode (4.4 V) also exhibit excellent cycling stability of 200 cycles with a good capacity retention of 83%. This noticeable electrochemical performance is due to the highly efficient passivation ability of the cyclic anions on both anode and cathode surfaces. This cyclic-anion-based electrolyte design strategy is also suitable for lithium and sodium-metal battery technologies.

Cyclic-anion salt for high-voltage stable potassium-metal batteries