A team of scientists at UNIST (Ulsan National Institute of Science and Technology) has made an exciting discovery that could lead to electric car batteries that are safer and last much longer.
Their work could help future electric vehicles drive up to 1,000 kilometers on just one charge—almost double the distance most EVs can go today.
The researchers focused on a new type of battery material called quasi-lithium.
This material can store 30% to 70% more energy than current battery materials, thanks to its ability to handle high-voltage charging above 4.5 volts.
However, there’s been a serious problem—when charged at such high voltage, the material can release oxygen gas.
This happens because the oxygen inside the material gets oxidized (a chemical reaction), which can cause pressure to build up and even lead to dangerous explosions.
Led by Professor Hyun-Wook Lee from UNIST’s School of Energy and Chemical Engineering, the team found that this oxygen release starts around 4.25 volts.
At that point, the battery material begins to change its structure slightly, and gas is released.
To solve this, the researchers designed a new version of the material by replacing some of the “transition metals” (a type of element in the battery) with other metals that have lower electronegativity—which means they hold on to electrons less tightly.
This clever change keeps more electrons available around the transition metals, preventing the oxygen from oxidizing and turning into gas.
First author Min-Ho Kim, a Ph.D. student at UNIST and postdoctoral researcher at UCLA, explained that most past studies tried to stabilize oxidized oxygen.
But their team focused on preventing the oxygen from being oxidized in the first place.
This approach has another benefit too: it boosts the battery’s voltage and energy density. Since energy storage depends on both the number of electrons and voltage, this design allows the battery to store much more energy without extra weight—like a dam storing more energy with more water and greater height.
The team tested their idea using powerful X-ray machines and computer models. By replacing part of the metal ruthenium with nickel, they successfully reduced the amount of oxygen gas released.
Their findings, published in Science Advances, could help battery makers build longer-lasting, safer batteries for electric vehicles and beyond.
Professor Lee said this research gives other scientists helpful tools to design better battery materials in the future.
