A graphene coating used to “wrap” a lithium battery can stop oxygen from escaping and this could prevent lithium battery fires. Graphene sheets are impermeable to oxygen atoms. Without the oxygen – combustion risk is reduced.
“Lithium batteries are what allow electric vehicles to travel several hundred miles on one charge. Their capacity for energy storage is well known, but so is their tendency to occasionally catch on fire—an occurrence known to battery researchers as “thermal runaway.”
These fires occur most frequently when the batteries overheat or cycle rapidly. With more and more electric vehicles on the road each year, battery technology needs to adapt to reduce the likelihood of these dangerous and catastrophic fires.
Researchers from the University of Illinois at Chicago College of Engineering report that graphene—wonder material of the 21st century—may take the oxygen out of lithium battery fires. They report their findings in the journal Advanced Functional Materials.
“The wrapped cathode battery lost only about 14% of its capacity after rapid cycling compared to a conventional lithium metal battery where performance was down about 45% under the same conditions,” Sharifi-Asl said.
“Graphene is the ideal material for blocking the release of oxygen into the electrolyte,” Shahbazian-Yassar said. “It is impermeable to oxygen, electrically conductive, flexible, and is strong enough to withstand conditions within the battery. It is only a few nanometers thick so there would be no extra mass added to the battery.
Our research shows that its use in the cathode can reliably reduce the release of oxygen and could be one way that the risk for fire in these batteries—which power everything from our phones to our cars—could be significantly reduced.”
Read the full article at Graphene coating could help prevent lithium battery fires
Source: Phys Org News
Image: Lithium cobalt oxide particles coated in graphene. Credit: Reza Shahbazian-Yassar.