The battery unit sustained severe fire damage, the safety board said, adding that it had sent two additional investigators to Boston.
Boeing said the fire was traced to a battery unit that helps to power electrical systems when the engines are idle -- typically while a plane is being serviced or cleaned.
Boeing said in a statement that the fire was traced to a battery unit that helps power electrical systems when the engines are idle -- typically while a plane is being serviced or cleaned.
The 2100mAh battery powers the unit for about 16 hours of use (60 hours on standby) and can be charged to 70 percent capacity in about an hour.
Richard Walsh, a Massport spokesman, said the jet's auxiliary power unit battery, which is housed in a small compartment known as the aft electrical equipment bay, exploded after crews believed the fire was extinguished.
According to Dr Tamanaha, the laboratory has developed a portable, battery-powered unit the size of a shoebox, and has licensed its technology to Seahawk Biosystems, a firm based in Austin, Texas, for food-testing and environmental applications.
The battery powers the auxiliary unit and provides electricity for ground operations.
Officials found that the battery for the aircraft's auxiliary power unit was incorrectly connected to the main battery that overheated.
The battery charger maker, a unit of Britain's Meggitt, said it would fully support the US investigation.
The ELR will run on an electric propulsion system made of a T-shaped lithium ion battery, an electric drive unit and a four-cylinder engine generator.
The next step for the safety board will occur on Tuesday in Tucson, Arizona, where the battery charger and power starter unit will be tested and relevant data downloaded.
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For example, you shut off the unit or the battery dies, and you have to start at the beginning or go through a medieval process of physically recording track numbers.
It said it would now widen its probe to look at the battery charger and the auxiliary power unit.
They were also digging its capable audio player -- with support for MP3, WMA and AAC files -- along with the unit's decent battery life, which clocked in at just around four hours.
Mr Leonard patrols regularly with the local commando unit, and maintains a battery-powered radio link with his white neighbours.
When detached from the PC, the small receiver unit, which has a rechargeable battery, stores whatever you write with the pen.
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On the plus side of things, the battery is a generous 1, 050 mAh unit, and there's a pleasingly instant access scheme for the camera's most regularly used functions.
Packed in their 7-by-2-foot titanium-framed fiberglass bodies are terabytes of cellphone flash storage, a dual-core ARM processor running open Linux software, a battery pack, sensor arrays, a GPS unit, and wireless and satellite communications systems.
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For this reason battery performance is usually measured in watts (a unit of energy calculated by multiplying voltage x amperage) per liter or watts per kilogram.
Japanese inspectors have cleared the maker of the battery, GS Yuasa, of any defects before the unit leaves the factory.
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The main investigation, which also involves the FAA and Boeing, focuses on the 787's cutting-edge lithium ion battery system that powers the plane's auxiliary power unit.
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In 10 hours of daylight charging the unit gathers up to 20 hours worth of battery power for use in the low-power 8 LED mode, or 10 hours of life if used in 16 LED mode.
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The unit is powered by a standard 120V or Ridgid 18V battery, and if you're curious as to just how hardcore this thing is, there's an enlightening video embedded just after the break.
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It also has a clever little display screen on the top of the unit for displaying caller ID information, the time of day, battery status and message alerts.
Furthermore, the whole back flips open to expose the 1, 050mAh battery (same as before), as well as the microSD card (a 4GB unit included is in the box).
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The unit has an LCD panel for status indication including record mode, frame rate, timecode and battery and media remaining time.
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The battery pack provides up to 16 hours of life on a single charge and will re-charge itself within the unit when external power is detected.
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The battery and car manufacturer, backed by United States billionaire Warren Buffett, plans to cut the workforce at the sales unit to 800 from 2, 600, according to a post from an unidentified laid-off employee on the Weibo.com microblogging site.
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