Extending Li-ion battery lifespans with X-rays

Open the battery health tab on your phone, and chances are pretty high that you’ll be disappointed. And the amount of time squeezed from a full charge only decreases from there.

That depreciation might seem unstoppable. But new UNLV-led research may prove the contrary, adding years to the lifespan of battery-powered electronic devices.

“A Tesla can drive for on average 340 miles on a full charge, but after a decade, maybe it only goes 200,” said Michael Pravica, a professor of physics leading the study. “My lab is trying to regenerate the battery’s capacity so that it’s basically very close to new and usable for much longer.”

The regeneration is applicable to battery packs on electric vehicles, electric trains, power banks used by businesses, cellular phones and any other device dependent on lithium-ion batteries.

“Replacing battery packs on electric vehicles can cost tens of thousands of dollars. Instead of getting 10 years of use from these cars, drivers may now be able to get 15 or 20 years, and save money in the process,” Pravica said.

Modern battery technology sees lithium ions move from anode to cathode, or the reverse when recharging. Through repetition of this process, ions become stuck, reducing battery health.

This is where the secret ingredient of this technological breakthrough comes in: X-rays. Typically thought of as medical diagnostic tools, X-rays are a form of highly concentrated light called electromagnetic energy — essentially used as a chisel on the battery.

“We realized that X-rays would be a good way to force out lithium ions that get caught in microscopic fractures as these batteries degrade,” Pravica said. “And we would be able to free them back into conduction instead of being stuck and reducing capacity.”

Historically, high pressure and temperature are used to bring molecules together and initiate this sort of chemical change. Pravica observed that X-rays are capable of doing the same, and have become a third mechanism for transforming chemicals.

“With X-rays, we can realise novel states of chemistry using very high energy,” he said. “As X-rays ionise, they strip electrons from molecules and atoms. But they’re so much higher energy that they can access new regions to achieve what we can’t through conventional chemistry.”

Video caption: Pravica talks about his upcoming research that could extend the lifespan of your devices. Video credit: John Domol.

Charging the economy

“The tech will allow electric vehicles and battery-powered products to hold their value for longer. If articulated well to business owners, I think they’ll come around to seeing X-ray regeneration as a win-win,” Pravica said. “Moreover, regenerating batteries will have enormous environmental impacts because it will delay, if not obviate, the need to dump them into landfills.”

The Environmental Protection Agency says that battery dumping can cause intense lead or acid leaks, and there are increasingly more detailed protocols for handling, recycling and disposal as pollution becomes a growing concern.

Pravica says any technology that could potentially slow the replacement of batteries is of high value to both the environment and economy, and he is working with the UNLV Office of Economic Development (OED) to bring it to life.

His lab plans to finish fundamental experiments needed to demonstrate that X-rays have positive effects on battery capacity in the fall. These include toying with the brightness or intensity, and energy of the X-rays to see what changes those factors present to the value proposition of resurrecting batteries.

“There are always going to be hurdles, but to have a feeling that I did something useful for humanity is just priceless,” he said. “I’m hoping the tests are all going to work, and that I’m able to make a good contribution to this community soon.”

Top image credit: iStock.com/MarioGuti