Skip to main content

Boeing announces changes to Dreamliner battery system

By Madison Park and Steve Almasy, CNN
updated 1:06 AM EDT, Fri March 15, 2013
STORY HIGHLIGHTS
  • Boeing says batteries in 787 Dreamliners will be housed in new enclosure
  • The batteries also were upgraded to prevent combustion, failure
  • Company president says he will fly on next Dreamliner flight

(CNN) -- Boeing spent more than 60,000 hours testing changes to the lithium-ion battery system for the 787 Dreamliner, which has been grounded in the wake of incidents on two planes, the chief project engineer for the project said Friday.

At a news conference in Tokyo, Mike Sinnett said the company "may never get to the single root cause" of the battery issues, which included a small fire on the front of the battery box of a plane that was on the tarmac at Boston's Logan International Airport on January 7. He said he believes improvements to the system will prevent problems.

One of the changes is a new fireproof, stainless steel enclosure around the batteries, which Sinnett said will prevent fires. He said engineers also minimized potential combustion sources in the lithium-ion batteries, and if there were a release of gas from the batteries, the enclosure would keep it from the rest of the airplane and vent vapors outside the airplane.

Dreamliner, A380: Headaches?
Dreamliner allowed to make 1 flight

Boeing has also proposed several solutions to prevent the battery malfunction, including limiting the voltage range to reduce the energy in the batteries, adding four additional tests for the batteries, and changing the charging unit.

"I get asked if the airplane is safe," Sinnett said. "My answer is absolutely. This airplane is among the safest airplane our company has ever produced."

There are 50 grounded Dreamliners worldwide, and Boeing has orders for several hundred more.

Boeing President and CEO Ray Conner apologized to passengers, the airlines and the Japanese people for the problems plaguing the company's newest and most advanced commercial jetliner.

Conner also repeated assurances that the plane is safe: "When the plane returns to the skies, I plan to fly on the very first flight."

Boeing executives could not give a definitive time frame for Dreamliner's return to service, as it is contingent on safety approvals.

The fleet has been grounded since January following the two battery-related incidents in Boston and in Japan. No passengers or crew were hurt in either incident.

"In neither event was the airplane structure damaged," Sinnett said.

The Federal Aviation Administration must approve the redesign before the Dreamliner can carry passengers again.

Earlier this week, the agency approved a proposal for the battery system. The company will have to successfully complete all required tests and analysis.

A group of engineers and technical experts examined potential causes for battery failure and identified about 80 possible factors such as overcharging and overheating, Sinnett said.

When the lithium-ion battery overheats, the cell's contents vaporize. The vaporization looks like smoke, he said.

Boeing has suggested an electrical insulator that wraps around each battery cell to isolate each cell from each other and the battery case.

"In the design changes we made to the battery, we've minimized potential ignition sources, we have eliminated the ability for oxygen to begin or sustain combustion. If a battery fails, I'm very, very confident we will not have a fire as a result," Sinnett said.

The batteries are not essential during flight as they are mainly used on the ground during maintenance activity, Sinnett said, such as providing navigation lights and braking while the airplane is towed.

ADVERTISEMENT
Part of complete coverage on
CNN recommends
updated 11:53 AM EST, Wed February 12, 2014
Are abandoned buildings urban blight or historic relics? Photographers love them, in either case.
updated 12:00 PM EDT, Fri March 14, 2014
The lush Emerald Isle is easy on the eyes.
updated 1:49 PM EDT, Fri April 4, 2014
Usually, a ride on an elevator involves pushing a button and zoning out until the ding for your floor. It's so much more on these lifts.
updated 8:17 AM EDT, Wed March 12, 2014
From swimming pool slides and oversized LEGO stations to Plinko walls and Wii consoles, hotels all over the world have committed to having fun.
updated 5:25 PM EST, Fri January 17, 2014
Earth never stops surprising us. Every corner of the planet offers some sort of natural peculiarity.
For 24 hours, we made the world's busiest airport our destination and found a world unto its own. Join us on our journey. What you see will surprise you.
updated 3:21 PM EST, Tue February 11, 2014
Some roadside attractions have become kitsch institutions. You might even make a trip just to see them.
updated 11:27 AM EST, Mon February 4, 2013
Check out daily travel photos from CNN.com readers and share your best shots.
updated 10:02 AM EST, Thu January 2, 2014
The coasts get all the glory in the United States, but there's something fun to do in each and every state. Yes, every state.
updated 3:34 PM EDT, Tue August 13, 2013
Beaches along the coasts of the United States call to shoreline explorers year-round.
updated 9:01 PM EDT, Fri July 27, 2012
When five teenagers sat down and posed for a picture at Copco Lake in 1982, they didn't plan on making it a tradition. But that's what it became.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT