New airline safety worry: lithium-ion batteries

it causes may not be as easy to extinguish as a normal combustion fire.

FAA data show that from 20 March 1991 through 3 August 2010, batteries and battery-powered devices were involved in 113 incidents with “smoke, fire, extreme heat or explosion” on passenger and cargo planes. The data are for lithium and non-lithium batteries and are not a complete list of such incidents, the agency says.

In January, the U.S. Department of Transportation (DOT) proposed stricter rules for companies that ship lithium batteries in cargo holds. “The frequency of incidents, combined with the difficulty in extinguishing lithium-battery fires, warrants taking strong action,” Representative Jerry Costello (D-Illinois), chairman of the House aviation subcommittee, said of the Transportation Department’s proposal.

Stoller writes that lithium-battery experts, security analysts, and flight attendants wonder, though, whether stricter rules are also needed in airline passenger cabins to prevent fires or worse: a possible attempt by a terrorist to bring down a plane by rigging a large number of batteries together to start a fire. “Right now, there’s no limit to how many small lithium-ion batteries a passenger can carry aboard a flight,” Soller notes.

Some scientists who have studied the batteries raise doubts about the safety of the ones passengers carry on board flights in their electronic devices, even those as small as those used to power cellphones.

• Jian Xie, a mechanical engineering professor at Purdue University School of Engineering and Technology in Indianapolis, says portable electronic devices are “pretty safe” for consumers. He says, however, that they could be rigged together for a bomb. Xie, who is doing lithium-ion battery research for the military, says it is “scary” that a passenger with fifty or so electronic devices, including numerous lithium-ion batteries for cellphones and laptops, boarded an aircraft (as the passenger on the 23 June American Airlines New York flight to Buenos Aires did). “I would be very uncomfortable on that flight,” he says.
• Amy Prieto, a Colorado State University chemistry professor who also is a lithium-battery expert, told Stoller that several batteries could start fires that would be difficult to put out. She says, though, that even fifty batteries rigged together “wouldn’t be like a bomb that would take down a plane.”
• Dan Abraham, a materials scientist at the Argonne National Laboratory in Illinois, says even a single cellphone battery could start a fire. “A smart terrorist can start fires with these things,” he says. “Any energy-storage device packs a lot of energy in a small space and can be used for good or evil.”

The FAA, which regulates flight safety, classifies lithium batteries as hazardous materials because they “present chemical and electrical hazards” and are a fire risk — but the FAA and its parent agency, the Transportation Department, do not limit the number of lithium-ion batteries for laptops, cellphones, and some other portable electronic devices that passengers carry aboard. There is a limit for other lithium batteries with higher lithium content.

Stoller notes that the FAA concerns about the fire risks of lithium-ion and lithium-metal batteries are so great that passengers aren’t allowed to put spare ones in checked bags. They can, however, put them in checked bags if they are attached to an electronic device.

The Transportation Department in January proposed that shipments by manufacturers and distributors of batteries for laptops, cellphones, and many other portable devices be included in stringent hazardous materials rules for cargo holds.

Battery manufacturers must retain results of design and safety tests, and their batteries must be more safely packaged and more safely stored on aircraft, the DOT rule says.

In passenger planes, they would have to be stored in more fire-resistant cargo compartments with fire-extinguishing systems. In FedEx and other cargo planes, they would have to be stored in areas accessible to pilots in the event of a fire.

Battery and electrical equipment makers oppose the proposed Transportation Department rules. They say the rules are costly and more onerous than those of the International Civil Aviation Organization, which sets standards for 190 countries’ aviation authorities.

A restriction on storage of batteries in cargo planes may result in greater quantities being shipped on passenger planes, says George Kerchner, executive director of the Portable Rechargeable Battery Association.

The Airline Pilots Association, which represents nearly 53,000 pilots at U.S. and Canadian airlines, says the proposed rules will make flying safer for passengers and flight crews.