The NTSB has since called for a limit to be place on the quantity of the batteries permitted on cargo flights. It has also highlighted a need to separate the batteries from any hazardous material as they represent an ignition source, a fuel to any existing fire and can create an explosive environment (when subjected to overheating).
The Federal Aviation Administration (FAA) has also stressed that current procedures for dealing with fires on planes were incapable of controlling a lithium-ion battery blaze, and that a fire involving lithium-ion batteries would result in ‘potential risk of catastrophic aircraft loss’.
In previous tests, the FAA filled a cargo container with 5,000 lithium-ion batteries and a cartridge heater, which was added to simulate a single battery overheating. The heat from the cartridge triggered a chain reaction in other batteries, with temperatures reaching about 600°C.
This was followed by an explosion, which blew open the container door and set the cargo box on fire. A second test produced similar results, despite the addition of a fire suppression agent.
US senator Bill Nelson now plans to introduce legislation that would allow the FAA to ban lithium-ion shipments.
“If FAA testing has found that fires or explosions caused by lithium-ion batteries can lead to a catastrophic loss of an airplane, then why on Earth would anyone want to prohibit safety regulators from banning large shipments of these batteries on passenger airliners,” he said.
Lithium-ion batteries are used in many portable devices and production is forecast to reach eight billion by 2025. However, early last year, both United Airlines and Delta Airlines announced the cessation of bulk shipments of lithium-ion batteries.