Boeing said the problem on a Japan Airlines 787 was discovered during scheduled maintenance. No passengers were on board. The company said it appears that a single battery cell 'vented,' or released gas.

Washington: Battery problems resurfaced on Boeing's 787 today, after gas was discovered coming out of a battery on a plane parked in Tokyo.

Boeing said the problem on a Japan Airlines 787 was discovered during scheduled maintenance. No passengers were on board. The company said it appears that a single battery cell "vented," or released gas.

The incident comes a year after a fire in a lithium ion battery aboard a Japan Airlines 787 parked at Boston's Logan International Airport. That was followed nine days later by another battery incident that forced an emergency landing in Japan by an All Nippon Airways 787.

Those problems prompted the FAA and other authorities to ground all 787s for more than three months. The planes began flying again after Boeing changed the battery system, adding a tougher box to hold the battery and measures to contain any short-circuit or fire.

Boeing said those changes appear to have worked as designed in the battery incident today. It said it's working with Japan Airlines to get the plane flying again.

Because the incident happened in Japan and involved a Japanese airline, Japanese authorities would take the lead in any investigation. If the Japan Transport Safety Board opens an investigation, the US National Transportation Safety Board "would certainly participate," NTSB spokesman Peter Knudson

said.

The NTSB expects to finish its investigation of the 787 fire in Boston by the end of March, and present findings at a public meeting this fall.

"Anything we can learn about the (latest) battery failure would be helpful" to the ongoing investigation, Knudson said. Representatives for Japan Airlines did not respond to requests for comment.

AP