WASHINGTON (AP) - International aviation officials are trying to quickly come up with safer packaging for cargo shipments of lithium-ion batteries on passenger planes, after U.S. testing confirmed that aircraft fire suppression systems can't prevent overheated batteries from causing a powerful explosion.

WASHINGTON (AP) International aviation officials are trying to quickly come up with safer packaging for cargo shipments of lithium-ion batteries on passenger planes, after U.S. testing confirmed that aircraft fire suppression systems can't prevent overheated batteries from causing a powerful explosion.

The International Civil Aviation Organization's committee on hazardous cargo met this week in Montreal. Officials familiar with the discussions say the panel heard a detailed presentation by aircraft manufacturers and pilot unions on the potential for the batteries to cause an explosion and fire capable of destroying a plane.

If a working group cannot come up with packaging capable of containing an explosion or fire, union officials said they will consider offering a formal proposal at a meeting in October to ban bulk battery shipments.

The batteries are used in devices from cellphones to electric cars. It's not unusual for as many as 80,000 batteries to be carried on board a plane.

Federal Aviation Administration tests over the past year and a half show that a single short-circuiting battery in a large shipment of batteries can cause overheating to spread to other batteries. Fire suppression systems have been able to put out the flames, but do not stop the spread of continually increasing temperatures known as thermal runaway.

The overheated batteries emit a mixture of explosive gases, of which hydrogen is the most abundant. As the gases build up, they eventually explode and ignite a fire.

An FAA test in February resulted in a powerful explosion despite an atmosphere of 5 percent halon, the main gas used to suppress fires in passenger aircraft.

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