Loose lithium batteries require careful handling. They’ve been blamed for an

Another kind of energy crisis

While no one will stop you from stowing batteries on your own aircraft, the U.S. Department of Transportation has banned all loose batteries from checked baggage on airline and charter flights for reasons that seem just as applicable to privately owned jets.

"If a battery is in an electrical device that it's rated for, you can place it into checked baggage," explained Gordon "Joe" Delcambre Jr., a public affairs specialist at the Department of Transportation. "Everything else can go into carry-on baggage. So you can carry nearly all the devices that people use now-cellphones, laptops, PDAs, iPods." Delcambre added that a special limit-two spare batteries per carry-on per person-applies to unusually large rechargeable lithium batteries.

Why the restrictions? Since February 2006, the Consumer Product Safety Commission  has recalled more than nine million rechargeable lithium batteries in laptop computers and other products because of design problems. CPSC and FAA records show that rechargeable lithium batteries are causing an increasing number of fires and that incidents involving nonrechargeable lithium batteries have also begun to increase. (See "Battery Trouble.")

One problem with nonrechargeable lithium batteries is that people try to recharge them, explained consultant Jeff Hare, president of J. Hare Safety & Survival Systems, Inc. of Jamaica, N.Y. "That's just looking for trouble," he said. Also, if you accidentally drop the battery, causing internal damage, the resulting short circuit will lead to what's known as thermal runaway. With thermal runaway, heat builds, slowly destroying insulation inside the battery until it self-destructs and potentially causes a fire. Just having a few lithium batteries banging around in a suitcase could result in thermal runaway-reason enough to not have them in the cargo hold.

But that's not the only concern. "A nonrechargeable battery, such as lithium sulphur dioxide or lithium magnesium dioxide, poses a more significant potential problem than even most flight crews realize," Hare said. "A fire caused by that type of battery requires a Class-D fire extinguisher, and aircraft don't carry those, so you don't have the means to extinguish the fire in-flight."

One way to avoid trouble is to keep extra batteries in their original blister packages. "None of the incidents involve consumer-type batteries in their retail packaging," said Bill Wilkening of the FAA's Office of Security and Hazardous Materials. If you have loose batteries, Wilkening suggested, simply put a piece of tape on each end to prevent metal-to-metal contact.

Battery Trouble

Why all the fuss about batteries? Some recent incidents:

• A news crew aboard a JetBlue flight departing from a New York airport stored its audio/visual gear in an overhead compartment. A fire broke out in one of the equipment bags, forcing the aircraft to make an emergency landing shortly after takeoff. The subsequent investigation found the most likely source of the fire to be a nine-volt lithium battery.

• A UPS aircraft crewmember packed a flashlight purchased in China in his flight bag, which he stowed in the cockpit. The flashlight began to smoke, and its lithium batteries later were confirmed to be counterfeits.

• A lithium battery exploded when an airline passenger accidentally dropped it during a flight from Buenos Aires to Miami.

• A laptop and spare lithium-ion battery stowed in an overhead bin on a transatlantic flight began burning minutes before pushback from the gate. The computer was removed from the aircraft to the ramp, where ground personnel extinguished the fire.

• Several incidents have occurred involving lithium batteries that powered personal air filters worn around the neck. Inappropriate charging of nonrechargeable lithium batteries is suspected as the cause in two of these incidents, which manifested themselves in flaming necklaces.