A sample text widget

Etiam pulvinar consectetur dolor sed malesuada. Ut convallis euismod dolor nec pretium. Nunc ut tristique massa.

Nam sodales mi vitae dolor ullamcorper et vulputate enim accumsan. Morbi orci magna, tincidunt vitae molestie nec, molestie at mi. Nulla nulla lorem, suscipit in posuere in, interdum non magna.

Boeing Discloses Fixes for Lithium-Ion Batteries

¶ Boeing officials have detailed for the first time their proposed fixes for the lithium-ion batteries aboard its 787 planes, and the changes include better insulation between the eight cells in the battery, gentler charging to minimize stress and a new titanium venting system.
Enlarge This Image

One change proposed for the Boeing 787 is to seal its batteries in a steel box, which would contain any smoke and fire.
A Rocky Path for the 787 Dreamliner
Add to Portfolio

Boeing Company

Go to your Portfolio »

¶ But to prevent any new fire and smoke episodes like the ones that have grounded its fleet, Boeing proposed the crudest tool in its considerable technological arsenal: the battery itself will be sealed inside a steel box that would serve as the last safety rampart if everything else fails.

¶ The Federal Aviation Administration approved these changes on Tuesday, and Boeing has since begun a series of 20 certification tests that it expects to wrap up in one to two weeks. Most of the tests will be conducted inside Boeing labs, with only a single test flight planned since the plane’s two batteries are not used while in normal flight.

¶ The 50 787s delivered to airlines so far have all been grounded since mid-January after two planes developed battery problems; one battery ignited while a plane was parked in Boston and another forced an emergency landing in Japan when it began to smoke. With significant commercial and financial stakes in the balance, Boeing is keen to rapidly resume passenger flights, though government officials have been more cautious about the timing.

¶ But the new safety features, made public late Thursday, were an admission that despite its substantial resources, Boeing might never determine what went wrong with the batteries. Still, the changes are intended to reassure regulators and the public that the planes are safe and should be allowed to fly again soon.

¶ “This enclosure keeps us from ever having a fire in the beginning,” Mike Sinnett, the 787’s chief engineer, said during a news conference in Japan along with Ray Conner, the president and chief executive of Boeing’s commercial airplane division. “It eliminates the possibility for fire.”

¶ Mr. Sinnett said that Boeing engineers had identified 80 different ways that the batteries could fail and modified the batteries as a result. But if, for whatever reason, a cell did overheat and combust, the steel casing would contain the smoke and fire, the venting tube would open, and the smoke would be pushed outside the plane instead of venting inside the cabin.

¶ Donald R. Sadoway, a materials chemistry professor at M.I.T., was not persuaded that Boeing’s plan went far enough. He said Friday that the proposals seemed intended to mollify the F.A.A. to lift the grounding of the planes, but the approach seemed to focus more on dealing with a battery failure rather than preventing one. He pointed out that automakers had developed large-format lithium-ion batteries without encountering the problems Boeing has had.

¶ “It doesn’t have the look and feel that they are going to extreme measures to make sure this thing is robust,” he said


Leave a Reply