(UPDATED with information on control circuit, below the photos.)
From Yomiuri Shinbun (1/18/2013):
Reuters reports (1/17/2013) that the control circuits for the batteries in Boeing 787 are made by a French company Thales SA, and they are part of a power unit supplied by a US company UTC Aerospace, part of United Technologies Corp:
- Boeing's new 787 airliner uses two lithium-ion batteries made by the Japanese company GS Yuasa Corp (6674.T), with the associated control circuits made by Thales SA (TCFP.PA). They are part of an auxiliary power unit supplied by UTC Aerospace, a unit of United Technologies Corp (UTX.N), that provides power while the airplane is on the ground.
- Lithium-ion batteries can catch fire if they are overcharged, and once alight they are difficult to extinguish because the chemicals produce oxygen. But Boeing said it designed multiple systems to prevent overcharging, contain a battery fire and siphon smoke away before it reaches the cabin.
- Boeing said the battery it uses on the 787 is about twice as large as a car battery and has been extensively tested, both in the lab and in operation. The U.S. National Transportation Safety Board said the auxiliary power unit battery that caught fire on January 7 at Boston's Logan International Airport weighed about 63 pounds and measured 19 inches by 13 inches by 10.2 inches.
There is a speculation (not yet proven) that the controller was built on one of a bad circuit board batch produced in Mexico in both JAL and ANA planes.
(H/T reader netudiant)
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11 comments:
I wonder what caused these batteries to fail catastrophically. Was it improper installation? A flawed manufacturing process? Poor engineering? Corporate sabotage? I hope the answer that is eventually given is clear so that we can learn from this and make flying in this new airliner as safe or safer than anything that has come before it. I really hope the tech isn't flawed. Battery tech is still pretty crap as it stands. This would set things back a bit more if the safety of liion tech came into more question than it already has.
My guess would be wiring, Japanese can't wire properly or run nuke plants properloy.
RJ
That looks nasty!
I'M traveling on ANA back to the States next month. I've checked and we're not using one of the NightmareLiners.
But, I think it's the higher elevation thats causing these problems in connection with some defect in manufacturing, since it's not occurring in all them.
Check out LItium (LI) battery damage due to radiation...were the batteries MADE in Japan? Internet search shows interesting concerns and discussions....
Anon 5:30, this is not a place for "baseless rumors". Take it elsewhere.
Okay, so all these cellphones, laptops, Government Motor's Volt, Fiskr's Karma that have been catching fire for the past several years are also due to Fukushima radiation? That's quite a news.
http://www.aviationweek.com/Article.aspx?id=/article-xml/AW_01_21_2013_p22-537845.xml&p=1
From the article which much more on the events...
"...The problem lies with the lithium at the heart of the battery. Although this has twice the electrochemical potential of other materials, it also melts at a much lower temperature than other battery fuels, such as nickel. Energy experts in contact with Aviation Week say lithium melts at 357F—versus 2,800F for nickel—and acts “like molten sodium” in the process..."
The battery is most likely not the source of this problem. Lithium batteries are reliable and safe power sources, provided that their constraints are respected.
One of these constraints is that the charging be cut off once the battery reaches full charge, not an easy task as each battery contains several cells, each of which has to independently monitored and managed.
Finding the source of the problem is further complicated by the convoluted 787 supply chain. Participants producing this unit include battery power system by Thales, France, voltage controller by Meggit, UK, batteries by Yuasa, Japan, the overall power management by United Technologies, US. Boeing retains responsibility for the entire system. The actual manufacture of the parts involved is further spread into lower cost sites, so the list of contractors offers no clarity for an outside observer trying to determine what is produced where.
Obviously, that also complicates the troubleshooting process, so the grounding of the aircraft may be longer than Boeing and its customers would like. Moreover, the regulators will want to determine why the when the battery failed, the damage was not successfully contained and gases vented outside the airplane, as the design had specified.
My guess is that Yuasa will be found blameless, their gear did what it was supposed to, but that it was abused because of a manufacturing error. A design fault seems less likely, because the failures both happened in routine operations, which have been amply verified.
That said, the public impact is such that a battery replacemnt may be done anyway, just to show that corrective action was taken.
Interesting that there are two battery packs on 787 planes and both of them failed on different flights while in standby or idle mode. A charging problem?
As the young worldwide 787 fleet sits on the ground, it will take months for Boeing to convince the FAA that the design is sound or the plane will have to be re-certified using different battery packs.
So far, attention has been to possible physical defects (wiring, CPU, and other parts of the battery) and production issues (assembly errors, poor installation, etc.). But they should be also checking the software. I hear that battery chemistry is extremely dangerous and that managing it and keeping the chemicals in control (software function) is very difficult. Whey the battery reaches full charge during the flight, charging has to be cut off safely; when the plane is at the airport, this battery has to be turned back on and resume its function safely, all the while the battery chemicals have to be controlled carefully by software.
When one conceives the issue at hand, i have to agree with your endings. You
intelligibly show cognition about this topic and i have much to learn after reading
your post.Lot's of greetings and i will come back for any further updates.
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