Scientists at a German university have developed a new battery chemistry for zinc-air batteries based on an innovative, non-alkaline, aqueous electrolyte.
The full zinc-air batteries can reportedly operate stably for 320 cycles and 1,600 hours under ambient air atmosphere.
An international research team led by scientist Dr. Wei Sun at MEET Battery Research Center at the University of Muenster say they have overcome the technical obstacles that hindered the chemistry.
Until now, conventional zinc-air batteries have struggled with a high chemical instability and parasitic reactions rooted in the usage of alkaline electrolytes, which led to electrochemical irreversibility.
The scientific team published the detailed results of their research project in the journal Science.
The research included work by scientists from Fudan University in Shanghai, the University of Science and Technology in Wuhan, the University of Maryland and the US Army Research Laboratory.
Dr. Sun said: “Our innovative, non-alkaline electrolyte brings a previously unknown reversible zinc peroxide (ZnO2)/O2 chemistry into the zinc-air battery.
“Compared with the conventionally strong alkaline electrolytes, the newly developed non-alkaline aqueous electrolyte, which is based on the zinc trifluoromethanesulfonate salt, has several decisive advantages including the zinc anode is used more efficiently with a higher chemical stability and electrochemical reversibility.”
The mechanism of this ZnO2/O2 battery chemistry and the role of the hydrophobic trifluoromethanesulfonate anion were systematically revealed using electrochemical, analytical techniques and multiscale simulations.
The identified increased energy density has the potential to compete with lithium-ion batteries.
However, the technology requires further, intensive research and optimisation before it’s ready for commercialisation.