South Korean researchers have designed a power pack that reliably provides energy using salt and air, both abundant or free ingredients that could lower the cost of batteries.
Part of the sodium/air breakthrough is unlocking the ability to use the atmosphere around us instead of pure oxygen. Ambient air includes moisture and elements that typically degrade batteries as they operate, according to the research team at Pohang University of Science and Technology. The findings were published in Nature Communications.
"Utilizing ambient air as a fuel source, we constructed Na-air cells based on NASICON solid electrolyte," the researchers wrote, referring to the element symbol for sodium, Na.
NASICON, or Na Super Ionic Conductor, is a class of solid-state electrolytes with high conductivity and electrochemical stability, per the journal. Solid-state power packs are touted by many experts as the future industry standard because of their high energy density and low fire risk. The latter is a rare yet potentially serious concern for common batteries with liquid electrolytes, the substances where ions cycle between electrodes during operation.
But, as TopSpeed noted, developing a reliable solid electrolyte and manufacturing process has been a hurdle in development.
Pohang's findings are a possible answer to multiple challenges.
"NASICON … delivers a much higher discharge potential … than other metal-air batteries, resulting in high energy density and achieves [greater than] 86% energy efficiency at [more than] 100 cycles," the experts wrote in Nature Communications.
The chemistry "takes advantage of moisture in ambient air," forming a reversible reaction that creates a charge/discharge cycle. The method creates a catholyte, acting as both an electrolyte and an electrode, or active material.
"Our results demonstrate the reversible use of free ambient air as a fuel, enabled by the reversible electrochemical reaction of carbonates with a solid electrolyte," the experts wrote.
The team used a screen printing technique to apply the crucial NASICON layer to the "dense" solid electrolyte.
The lengthy lab summary in Nature Communications includes diagrams, formulas, and high-tech descriptions about the breakthrough.
If it all results in a better power source for our devices, electric vehicles, and even large-scale energy storage, the research could help transform our electricity generation system to use primarily renewable energy.
About 20% of U.S. electricity is made by renewable sources, including the wind and sun, according to the U.S. Department of Energy.
In the meantime, you can better use energy at home with some simple cost-saving moves. By choosing the cold cycle on your washing machine, you can eliminate 90% of the energy required to complete the load, simply by not heating water. If you wash a load per day, this can save about $250 a year.
Smarter energy use, combined with better battery tech from experts at Pohang and elsewhere, can help reduce planet-warming air pollution that is impacting even the depths of our oceans. Rising sea temperatures are contributing to weather pattern changes, according to the U.S. Environmental Protection Agency.
For now, the team in South Korea is going to try to stay ahead of battery demand with cutting-edge science, opening new alternatives to costly, lithium-based packs.
Lithium-ion battery demand "will overwhelm the pace of their development as the thermodynamic limits … are reached," the experts wrote in their report.
Join our free newsletter for weekly updates on the coolest innovations improving our lives and saving our planet.
Cool Picks
