Battery Failures: Beware Lithium-ion Dangers

Onboard lithium-ion batteries present a growing danger to operators of business aircraft, John Cox, CEO of Safety Operating Systems, told attendees at the recent FSF-NBAA Business Aviation Safety Summit (Bass).

In fact, the lithium-ion battery-overheat threat cuts across all industry boundaries, including military and general aviation, said Cox, also a fellow of the Royal Aeronautical Society (RAeS). “We must [learn to] deal with battery fires aggressively or the issue could grow dramatically to present a serious threat to all airplanes,” he warned.

“What are we going to do with an overheating device on the flight deck?” Cox asked. “How do you fight the fire and fly the airplane? How do we protect crewmembers from the molten materials that can be spewed from a lithium-ion fire?” Containment of the device in a temperature-resistant pouch or dousing it with water have been identified as the best avenues for tackling such an overheat, but “What’s the collateral damage from dumping all that water on or near sensitive cockpit electronics?”

Fire from an overheated lithium-ion-powered device can quickly create enough smoke and hazardous fumes to overcome a pilot or cabin crewmember, Cox explained. The FAA says its research shows that smoke volume and density can easily reach a 50-percent concentration in less than five minutes, but Cox showed a video that proved the 50-percent level can be reached in as little as 35 seconds.

Problem Can Keep Growing

“Between 2007 and 2015, there were 18 accidents attributed to smoke and fire and about 900 events related to smoke and fire recorded in the U.S. alone,” said Cox, citing RAeS research initiated in 2007 and updated twice since. That’s about three a day. “The Association of Flight Attendants in 2009 reported just over 1,000 smoke events,” he noted, and that number climbed 20 percent the following year. “These numbers are headed in the wrong direction.” Between 1991 and October 2012, Cox said, there were 132 battery fires reported; 20 more have been documented since. “The industry is beginning to come to grips with the lithium-ion battery problem, but slowly,” he said.

To illustrate the magnitude of the threat, Cox explained that the airline industry worldwide carried 3.3 billion passengers in 2013 and that everyone on board carries between three and four battery-powered devices. The battery manufacturing industry claims a reliability rate of one defect per 10 million units. That alone translates into 330 potential overheats annually. Cox thinks the battery industry’s numbers are too conservative and sit closer to one in 200,000. That translates into the potential for some 16,000 battery overheats annually, a deeply disturbing number, especially in light of the lack of on-board equipment to douse such a blaze. “And how do we cope with the panic in the cabin when a device overheats and begins spewing smoke and toxic fumes?” Cox asked.

The risk of a lithium-ion-powered device overheating rises significantly when the device is crushed or broken, left sitting in the sunlight or is charged improperly. Cox pointed to the threat of cheap chargers that are often missing important overcharge protections. “When people see a $50 Apple charger or one at the local store for $10, which do you think they will choose? Airlines are now offering generic chargers on board and creating their own problems,” he pointed out.

“The likelihood of an event is greater today than [it was] yesterday and will become greater tomorrow,” he concluded. The FSF, NBAA and other industry groups are trying to create a consensus statement to use when they approach the FAA about a formal response plan to lithium-ion fires.