Imagine an electric car that could travel across the country without stopping to recharge, or a drone that could stay in the air for hours instead of minutes.
These possibilities may come closer to reality thanks to a new catalyst that could help unlock the enormous potential of lithium–oxygen batteries.
Lithium–oxygen batteries, also known as lithium–air batteries, have attracted scientists for years because they could theoretically store up to 10 times more energy than today’s lithium-ion batteries.
Such a leap in energy storage could dramatically extend the driving range of electric vehicles and improve many other battery-powered technologies.
However, one major challenge has prevented these batteries from reaching the market. The chemical reactions involving oxygen that occur when the battery charges and discharges are extremely slow and inefficient.
This wastes energy, reduces battery performance and shortens the battery’s lifespan.
To solve this problem, researchers led by Professor Takahiro Ishizaki at Shibaura Institute of Technology in Japan developed a new type of catalyst that helps speed up these oxygen reactions.
Their findings were published in the journal RSC Advances.
A catalyst is a material that helps chemical reactions happen more quickly without being consumed in the process. In this study, the team combined two different metal oxides—lanthanum cobalt oxide and cobalt oxide—to create a single composite material.
Although each of these materials already showed good catalytic properties on its own, the researchers suspected that combining them could produce an even better result. They created the new material using a manufacturing process that could potentially be scaled up for larger production.
The team then carefully examined the catalyst using a variety of advanced laboratory techniques to study its structure, chemistry and performance.
The results were impressive. The new composite catalyst outperformed either material used alone and showed excellent performance during both charging and discharging.
One key measure of battery efficiency is the difference in voltage between these two processes. The smaller this gap, the less energy is wasted. The new catalyst reduced this gap to just 1.14 volts, representing a major improvement.
One surprising discovery was that the catalyst performed exceptionally well even though it had a smaller active surface area than the comparison materials. This suggests that the arrangement of atoms and the electronic properties of the catalyst are more important than simply having more surface available for reactions.
The researchers believe the outstanding performance comes from the interaction between the two metal oxides. Together, they create tiny defects called oxygen vacancies and produce an electronic structure that allows oxygen reactions to occur much more easily.
The new catalyst also performed better than commercial ruthenium oxide during one of the battery’s key reactions while approaching the performance of expensive platinum-based catalysts during the other. Because it relies on relatively inexpensive materials such as lanthanum and cobalt rather than large amounts of precious metals, it could offer a more affordable solution for future energy technologies.
Although the immediate goal is to improve lithium–oxygen batteries, the researchers say the catalyst could also be useful in other clean energy applications. It may help produce green hydrogen through water splitting, improve metal–air batteries and enhance reversible fuel cells used to store renewable energy from solar and wind power.
While lithium–oxygen batteries still require further development before they become commercially available, this new catalyst addresses one of the technology’s biggest obstacles.
If future research continues to build on these results, it could help create safer, longer-lasting batteries capable of powering electric vehicles, drones and renewable energy systems far beyond the limits of today’s lithium-ion technology.
