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        Discussion Battery in 787 swollen from overheating, official says

#1 jrb Jan 17, 2013 07:36 AM

Battery in 787 swollen from overheating, official says
1 Attachment(s)
Ugh: http://www.foxnews.com/world/2013/01...official-says/ .



#2 The Tug Jan 17, 2013 07:52 AM

Possibly they were using HK equipment.

#3 WCB Jan 17, 2013 07:59 AM


Originally Posted by The Tug (Post 23841385)
Possibly they were using HK equipment.

I hear Boeing has been attempting to contact HK ''customer service.'' :D

#4 Elios000 Jan 17, 2013 08:06 AM

this the 3rd battery issue they have had im betting a bad batch or some one ordered from HK lol

but really seems like a bad batch of batteries
any one know what chemistry they are using?

DERP its in the story

they are Li-Ion huh im going to say its a bad batch OR there charging circuit sucks

#5 The Tug Jan 17, 2013 08:10 AM

i read in the news Lithium Ion

#6 The Tug Jan 17, 2013 08:12 AM

looks like they were in a cannister to contain the fire,they must be reading RC Groups as well.

#7 Beckler Jan 17, 2013 08:37 AM

How big are the servos on the 787 anyway, that they would draw that much current...

#8 rampman Jan 17, 2013 08:43 AM

Sounds like several of us should submit a resume to Boeing. LOL
My guess is they under sized the pack or are charging it too fast over a bad design or a bad batch of cells. That would not slip through QA...or would it? :popcorn:

#9 bzfrank Jan 17, 2013 09:12 AM

The 787 has two rather large Li-Ion batteries, one in the forward EE compartment, one in the rear with the APU. Since the plane does not use engine bleed air for air conditioning / heating / de-icing (except for the engines themself), but does almost everything electric the needed power levels are rather high. The APU has two 225 kVA generators and the batteries have to compensate in case of failure.

The batteries are made by Yuasa:

Spec sheets: http://www.s399157097.onlinehome.us/...s/LVP10-65.pdf

From their spec sheet they seem to use a lithium cobalt cathode based cell chemistry. I don't know about the electrolyte but I suspect it to be lithium hexafluorophosphate based. (Rather similar to lipos for hobby purposes btw Good energy density but its comes with a price...)

The trouble - so I believe - is that this type of battery chemistry is not known to be self limiting in case of failure. In case of separator failure, overcharging or overheating it can sustain a thermal runaway resulting in the self destruction of the battery with fire and (toxic) smoke.

In hindsight maybe it would have been better if they had used LiFePO4/ LiFeYPO4 batteries. Maybe not quite the energy density but safer.

#10 Dan Baldwin Jan 17, 2013 09:15 AM


Originally Posted by jrb (Post 23841275)



Hmm. This is making me rethink my commute. I drive a Nissan Leaf, so I'm sitting on about 500 pounds of LiIon batteries. The car has seat warmers, but now I'm wondering if they could go into turbo mode. Why didn't someone warn me that Lipos could go up in flames before I bought this car? :D


#11 Elios000 Jan 17, 2013 09:17 AM

using APUs for primary power where have i heard that be for...

OH RIGHT the shuttle and they had all kinds of issues with the APUs (mind you Shuttles APUs ran on Hydrazine lol) but using an APU as primary power seems to be asking for trouble
not sure whats worse hydrazine fire or Li fire?

yes i know the 787s APU runs on JP-1

from that site that was linked

[B]attery management electronics which guarantees multiple levels of safety features.
lol sounds like the safety features need some bugs worked out... Boeing must be LIVID

#12 pilotpete2 Jan 17, 2013 10:08 AM

The 787 has twice the number of generators as traditional designs and they're double the wattage of those on a 777. Each engine has 2X 250kW generators, as does the APU, for a total of 6 generators. The total of four generators on the engines are the primary power source and provide a lot of redundancy.
The battery that caught fire in Boston was the starter battery for the APU.

#13 bzfrank Jan 17, 2013 10:57 AM

The batteries in the 787 are backup power, thats right.

But this is not a just puffed battery with a little discoloration of its paint. If the battery company say this is just "swollen" I would not want to see what a burnt one looks like:


In case of a fire in the forward EE compartment no amount backup power will help you. One of the Common Core Resource cabinets is a few inches away (the "brain" of the plane). The SOP in this case will be to land as fast as possible.

#14 JohnathanSwift Jan 17, 2013 10:58 AM

Did Boeing send (1) a photo? (2) a video? (3) a signed letter from "mother?"

#15 sparklet Jan 17, 2013 12:53 PM

I told them to go with Turnigy from Hong Kong.

Did they listen... ?

The results say they didn't !

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