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Investigators examine Boeing’s lithium-ion batteries


By Matt Tomsic
mtomsic@scbiznews.com
Published Jan. 21, 2013

Lithium-ion batteries have created startup issues in other industries that are similar to the problems now faced by the Boeing Co. and its Dreamliner program, which has been grounded while investigators look into issues with the batteries.

“The lithium-ion batteries are a thorn in the side of a number of people who are trying to use them,” said Paul Czysz, professor emeritus of aeronautical engineering at St. Louis University. “I just hope they can find the problem and isolate it. It’s not the airplane; it’s that one piece of hardware that is causing the problem.”

The Federal Aviation Administration, National Transportation Safety Board, Boeing and others are investigating a fire that damaged one of the batteries aboard a Japan Airlines 787 in early January, and investigators are also looking into an emergency landing by an All Nippon Airways 787 in Japan. The crew received messages in the cockpit about the battery before landing. Since then, the FAA has grounded Boeing’s newest plane to investigate the incidents and have already found that the battery damaged in the Japan Airlines fire was not overcharged.

Czysz said the batteries are the backup power system for the 787 and provide power while the 787 is on the ground. On older airplanes, like the 777, Boeing used lead-acid batteries, which were heavier and provided less power.

“They attempted to find the highest power-density batteries they could find that have the lowest weight for the power that they had to generate,” Czysz said.

The boost in electricity and power creates a hazard, though, making energy management more important because the batteries can overheat, said Eric Dietz, professor of computer and information technology at Purdue University.

The batteries have cells that provide power and a power-electronics circuit, Dietz said. The circuit monitors and ensures the battery’s health, and it also helps protect against overcharging the battery and overdrawing energy from it. Both ends of the spectrum can be failure points for lithium-ion batteries, he said.

The more often the batteries go from a 0% charge to 100%, the quicker they age and the more wear they receive. Users need a middle ground between drawing all the energy from a battery then overcharging it.

“There can be a little bit of a challenge to get this right,” Dietz said. “And that would be my guess of what we’re seeing with Boeing. I’m sure Boeing extensively tested this, but then there’s actually how people use things and that could be one of the things we’re seeing right now.”

Dietz said car companies have had similar issues with lithium-ion batteries on electric vehicles.

“There’s several pieces it could be,” he said, adding the answer to the issues could also be found in the batteries’ manufacturing process. “The things we’re seeing now, you hate to see them. It’s also not uncommon for anyone with a lithium battery system to have some startup challenges.”

Contact Matt Tomsic at 843-849-3144.

Previous coverage

NTSB to analyze auxiliary power unit controller aboard 787
U.S., European regulators ground Boeing 787
Federal aviation agency to review the Dreamliner
NTSB releases details on Monday’s 787 fire


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