The US National Transportation Safety Board has confirmed that it has asked Boeing to provide a full operating history of the lithium-ion batteries which have been used in the 787 Dreamliners owned by Japanese airline All Nippon Airways (ANA).
The request follows news from ANA that it changed the batteries ten times prior to the airline's 787 Dreamliners being grounded.
Speaking at a news conference, Megumi Tezuka, a spokeswoman for ANA, said that the replacements were partly due to the batteries failing to charge properly.
The New York Times reported that ANA had confirmed it told Boeing about replacing the batteries. These replacements occurred before the incidents which led to the aircraft being grounded.
ANA said that it wasn't required to report the issues to safety regulators as the problems were not deemed to be a safety concern.
On January 28th, Japan's transport ministry reported that airline safety inspectors had failed to find fault with the batteries themselves, indicating that the problem may be more far-reaching.
Shigeru Takano, a transport ministry official, said: "We have found no major quality or technical problem. We are [therefore] looking into affiliated parts makers. We are looking into possibilities."
This latest news follows a series of problems for Boeing's Dreamliners which began on January 7th when a fire started in a lithium-ion battery pack on a 787 owned by Japan Airlines after the plane landed at Boston airport.
On January 15th, a Dreamliner operated by ANA was forced to make an emergency landing at Takamatsu
in Japan after a smoke alarm sounded.
Both ANA and Japan Airlines grounded their Dreamliners on January 16th and this was followed closely on January 17th when all 787s were grounded.
Jim McNerney, CEO of Boeing, said on Wednesday (January 30th): "Our first order of business for 2013 is to resolve the battery issue on the 787 and return the airplanes safely to service with our customers."
Related news stories:JAL suggests it will ask for compensation from Boeing for grounded fleet (6th February 2013)All Nippon Airways and Japan Airlines ground 787 Dreamliners (16th January 2013)Japan Airlines Boeing 787 Dreamliner catches fire at Boston airport (8th January 2013)Japan Airlines expansion takes off with Boeing order (15th February 2012)