Engineers at Monash University in Australia have developed a new catalyst they say could bring zinc-air batteries “closer to real-world, grid-scale and transport uses.”
Monash University researchers have developed a cobalt-iron catalyst that significantly improves the performance and enhances the lifespan of zinc-air batteries, achieving remarkable stability over “thousands of cycles.”
Zinc-air batteries have long been heralded as a potential solution for large-scale energy storage and transport applications. They have high theoretical energy density, are made from abundant and inexpensive materials, and are considered safer than many conventional alternatives.
The path to commercialization for the technology has however been challenging with key obstacles including the slow kinetics of oxygen reduction and oxygen evolution reactions at the air cathode that leads to high charge/discharge overpotential, low efficiency, reduced energy capacity, and shorter cycle life.
Researchers from Monash University’s Department of Chemical and Biological Engineering have now engineered a cobalt-iron catalyst, dubbed CoFe-2DSA, that makes the battery’s oxygen reactions much faster and more efficient.
Using a heat treatment, they turned a 3D material into ultra-thin carbon sheets and added individual cobalt and iron atoms to create a catalyst that co-lead author Saeed Askari said outperformed standard commercial catalysts made from expensive metals like platinum and ruthenium.
“By engineering cobalt and iron as individual atoms on a carbon framework, we achieved record-breaking performance in zinc-air batteries, showing what is possible when catalysts are designed with atomic precision,” he said.
“Our advanced simulations revealed that the cobalt-iron atom pairs, combined with nitrogen dopants, enhance charge transfer and optimise reaction kinetics, solving one of the biggest bottlenecks for rechargeable zinc-air batteries.”
The researchers reported the CoFe-2DSA battery had “outperformed commercial and reported catalysts,” achieving a power density of 229.6 milliwatts per square centimetre and an energy density of 997 Wh per kilogram.
Additionally, the electrocatalyst exhibited exceptional cycling stability, maintaining consistent performance over 74 days and 3,552 cycles.
The researchers said the results pave the way for scalable innovations, including for grid-scale energy storage applications and as an alternative to current lithium-ion batteries in electric vehicles.
“Running a rechargeable zinc-air battery continuously for more than two months is a milestone for the field,” co-lead author Dr Parama Banerjee said. “It demonstrates that this technology is ready to move beyond the laboratory and into practical applications.”
The results appear in the research paper Synergistic electronic interplay between Co-Fe single atom and nitrogen on 2D carbon boosts bifunctional oxygen redox in metal-air batteries, published in the Nature Communications.
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