Why Are 'Hoverboards' Literally Catching On Fire?

One of the hottest gifts of the season is a little too hot — hot enough to catch fire.

Hoverboards have been burning up because of problems with their lithium-ion batteries.

From smartphones and laptops, to Teslas and Boeing 787s, lithium-ion batteries are in a lot of our everyday tech.

Jay Whitacre, a Professor of Materials Science & Engineering at Carnegie Mellon University, says that by nature, all lithium-ion batteries have a flammable electrolyte in them. And while most hoverboards are made safely, Whitacre points to two reasons for why this gadget in particular is having these kind of problems. Their batteries are more powerful than those in a smartphone or laptop, and some of those are poor quality.

"I think a lot of them are using second-tier battery sources which are going to have probably a higher rate of defects," he says. "These things have more lithium-ion batteries in them than most things because they're used to move you around. It takes more batteries to get you the power energy to do that and as such there's just more energy in a small space and so if something does go wrong, it's a bit more catastrophic."

Because of that danger, he offers two precautions: Don't overcharge your hoverboard, and don't use or charge indoors.

While this issue is even more uncommon in cellphones and laptops, big brand names have not been immune. Sony saw a lot of failures in its battery recall in 2006. But most of them, says Whitacre, "the Apple, the computer suppliers that we typically buy from in the United States, usually have top quality batteries inside of them."

But in the case of a fire with any device, he advises to put it in a non-flammable container like a bathtub and completely submerge it in water, as "they burn very hot and very fast."

While low, how does this threat fare on airplanes, with all the laptops and cellphones?

"Usually on an airplane you can contain it and it will maybe force a landing, but certainly not down the airplane," Whitacre says. "Both the U.N. and the North American Transportation Authority have been very focused on increasing the scrutiny on lithium-ion battery air shipment and making the rules more stringent. And I think for good reason. If it's in an unmanned cargo holder that holds lots of cells next to each other and something goes wrong it can be a real problem."