German scientists have made a significant step towards the development of a new generation of rechargeable batteries. A research team from the Technical University of Darmstadt has developed a special material that allows for repeated charging of zinc-air batteries, which were previously considered to be one of their biggest technological limitations. According to a press release from the university, the new catalyst was able to withstand up to 500 charge and discharge cycles under laboratory conditions. This discovery opens up further possibilities for the development of high-energy density accumulators.
Zinc-air batteries are not a new technology. They have been used for decades, for example, in hearing aids, where they have proven their ability to store a significant amount of energy in a relatively small space. However, they have a major disadvantage: conventional versions cannot be recharged and therefore end up as waste after being discharged.
This problem is now one that German scientists are significantly closer to solving. The research team, led by Professor Jörg J. Schneider from the Technical University of Darmstadt, has developed a new catalyst consisting of a combination of iron, nickel, and carbon nanomaterials.
The results of the research were published in the scientific journal Advanced Science at the end of September 2026. The university announced this on October 9th, and the scientific server Tech Xplore also reported on it on October 11th.
Batteries with up to five times the theoretical potential
Zinc-air batteries are attracting the attention of scientists primarily due to their high theoretical energy density. According to researchers, they can theoretically store up to five times more energy than lithium-ion accumulators commonly used today.
However, this figure represents the theoretical potential of the technology, not the result achieved with the newly developed battery.
One advantage of zinc-air cells is their operating principle. While conventional accumulators use active materials stored inside the cell, zinc-air batteries also work with oxygen from the surrounding environment.
During discharge, a chemical reaction involving oxygen occurs, while during charging, the reverse process must take place. Ensuring both reactions is one of the biggest technical challenges.
Previous technologies have had difficulty repeating these processes without losing efficiency and stability.
The key to success lies in tiny particles
German researchers focused on special materials known as spinels. These are a group of substances that also occur in nature and find applications in chemistry, electrical engineering, or materials science.
The scientists created extremely small particles of an iron, nickel, and oxygen compound, with dimensions reaching only a few nanometers. They then firmly attached these to carbon nanomaterials.
In addition, they incorporated nitrogen and phosphorus into their surface. The result is a composite material that can simultaneously conduct electric current, maintain chemical stability, and promote oxygen reactions.
It is precisely the combination of these properties that is crucial for the development of rechargeable zinc-air batteries.
According to a press release from the Technical University of Darmstadt, the new catalyst enabled up to 500 charge and discharge cycles under experimental conditions. The university also states that the operating time reaches up to 300 hours.
New technology may open the way to more efficient accumulators
An important part of the discovery is also ensuring the stability of the location where the three components meet inside the battery: the solid catalyst, the liquid electrolyte, and oxygen from the air.
This area, technically known as the three-phase interface, is essential for the proper functioning of the cell. If it loses stability during repeated charging, battery performance deteriorates.
The newly developed material creates conditions that allow the necessary chemical reactions to be maintained over a long period.
This research represents another step towards practically usable rechargeable zinc-air batteries.
In the future, similar technologies could expand the possibilities for storing electrical energy. However, in order to compete with current lithium-ion batteries, it will be necessary to verify not only their lifespan, but also their actual energy density, efficiency, cost, and reliability during long-term operation.
Although the results of the German research are encouraging, scientists have not yet presented a battery ready for mass commercial use. The new material has been tested under laboratory conditions, and its further practical application will require continued research.
However, it is crucial that progress has been made in an area that has so far hindered the wider use of rechargeable zinc-air batteries.
The discovery by German scientists shows that the future of energy storage may not depend solely on improving current lithium-ion technologies. New materials and chemical processes can gradually open the way to other types of batteries, which today remain largely in research laboratories due to technical limitations.