The airline industry wants passengers to be careful when travelling with lithium ion batteries.

Ben Wodecki is used to travelling the globe and is used to seeing airline crew at work. But flying into Las Vegas in June, the technology journalist saw something he'd never seen before, as worried looking flight crew dashed to the rear of the plane. "There was a glint of fear. They were dour. This was something more than someone being ill. It was something that affected them." As smoke, then distressed passengers emerged from the rear of the plane, it because clear what had happened. A passenger had been using a battery pack during the flight, and it had overheated before bursting into flames with a seat catching fire. Flight crew dropped the device into a container of water, Wodecki says. The plane then landed "fast and aggressively" at Harry Reid International Airport in Las Vegas, he explains, where it was met by fire crews on the runway. It was a dramatic end to a routine flight – and it illustrates why flyers are hearing more frequent and more insistent warnings about the dangers of bringing battery powered devices and specifically lithium-ion batteries on flights. These include warnings about trying to retrieve devices that slip into seat and pleas not to put lithium-ion devices in checked luggage. According to Jonathan Nicholson at the UK's Civil Aviation Authority (CAA), for the airline industry, lithium-ion batteries are "if not number one, within the top three risks for a good few years now". A US recent study showed, external the industry was affected by two lithium-ion battery related incidents a week worldwide, he adds. Those incidents could range from passengers belatedly realising they'd left a device in checked baggage, to devices smoking or catching fire in airport baggage halls, or on flights.