It's our battery cousins that are flaming out on Boeing 787s

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jray3

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GS Yuasa is the exclusive battery supplier for the Boeing 787, which just did an emergency u-turn to Tokyo after smoke in the cockpit, days after a lithium battery went thermal in a parked 787. :shock: I haven't been able to find any detail on which cells they are using in the planes, but this is the first use of lithium ion cells in a commercial airliner. Hard to believe that all the rest of those big birds are still lugging around nicads, like my EV conversion, but at least those are full of water and don't self-sustain a fire. (I should know, after loose/corroded connections have sent slag into the pack on more than one occasion!)
Wonder how much similarity our cells and BMS have to the Boeing batteries?
 
Okay. Point one. Why are they even using lithium's on a jet? The way the batteries are used on a plane keeps the lithium's at or near full charge all the time, which we know kills their lifetime capacity. That, and the thermal runaway issues that affect nearly all lithium chemistries would not be good sitting on the hot tarmac in the blazing sun in parked planes, although I would hope that the battery packs would have a half-decent thermal management system. NiMH batteries or even the NiCad's they use now are better suited to the application.

And point two. It's no wonder the batteries are having problems. From what I've heard, they are throwing these planes together so poorly that windows are falling out of them. Correct me if I'm wrong.
 
PV1 said:
It's no wonder the batteries are having problems. From what I've heard, they are throwing these planes together so poorly that windows are falling out of them. Correct me if I'm wrong.

:shock: Ouch, watch those rhetorical flames. You sound like a Boing Machinist: badmouthing my rebel bretheren when the strike-happy union prompted construction of a plant in South Carolina. I guarantee that local Seattle news will be asking whether the two planes in question were built in Washington or S. Carolina... (and the window cracked, but didn't fall out)
 
PV1 said:
Okay. Point one. Why are they even using lithium's on a jet?
Maybe because they're lighter and smaller for a given capacity? Every pound you shave off an aircraft equates to a significant fuel savings every hour you fly . . . . and after a few hundred thousand hours, that computes to some real $$$

Don
 
PV1 said:
Why are they even using lithium's on a jet? The way the batteries are used on a plane keeps the lithium's at or near full charge all the time, which we know kills their lifetime capacity. That, and the thermal runaway issues that affect nearly all lithium chemistries would not be good sitting on the hot tarmac in the blazing sun in parked planes.

Agreed with Don, weight savings are one obvious answer, and flooded nicads are rather maintenance-intensive, requiring watering and cleaning. The corrosive and conductive KOH electrolyte that they mist during charge (along with hydrogen gas) tends to create current leakage within the pack and to the case.
It would also seem fairly easy to configure a lithium pack for aerospace that is oversized and managed so that it never goes over 80% SOC, yet still provide significant savings on weight and maintenance. Regarding hot tarmac, I'd expect it to be far kinder service than our battery packs; which can 6" over broiling asphalt while locked inside a greenhouse.
 
Sorry, should have researched a little first. But still, these are serious problems that should have been worked out in testing before releasing the jet to the airlines.

I have no affiliation to the aircraft industry, ;) .
 
No doubt part of their problems are related to the fact that the Dreamliner is the most electrically 'intensive' aircraft that has ever been built - The wiring and the demands and loads on the electrical system are akin to those of a small town . . . . there are more neat electrical devices on the plane than you can shake a stick at - Even the huge windows (65% bigger than on any other plane) are translucent panels which require electricity to dim them

"The dimming effect is the result of an electrified gel sandwiched between two thin pieces of glass. As the electric current increases, the gel darkens and as it drops, the gel lightens. The system is brilliant in its simplicity."

My Dad worked for Boeing in Everett building 747's for nearly 30 years. What we're seeing is just the expected tech glitches you see with any all new plane . . . . and since nearly everything about this plane is completely new, there are likely to be a few more of them than usual. They'll all be flying again safe as ever in a week or two

Don
 
To me it looks like replacing their Battery Management Unit with a Flight Engineer might solve the burning batteries problem at least. :roll:

Battery Management systems are costly because of their proprietary nondisclosured patented horsemanure. They are so costly that it is worth the money to sue everybody who dares not believing in them and wording that disbelief. So every battery burnt by a battery management system will be declared killed by the Almighty or Darth Vader but the BMS was without fault because the team researching the fire is afraid of the lawyers.

It is like those may people who died of a heart attack - after they were hit by a bullet.

The plane looks nice and I trust it. It never has lost engines who tried to destroy the wings when they gave up their ghost like another very new plane has done.

Did you know the the airline with the most returned airplanes back to the airport because of technical issues is actually the safest airline with the fewest accidents?

So keeping an airplane down on the ground means they dont want to risk our lives and not the planes are bad.
 
http://www.greencarreports.com/news/1081753_boeing-787-batteries-same-as-those-in-electric-cars-umm-no

So they're using lithium cobalt chemistry. :roll:
Can't imagine why, other than the long development schedule for this bird may have locked in the battery before better options were available. Besides, Tesla has proven success managing a relatively unstable lithium chemistry. I know an engineer who was on the prototype flight test crew and is a DIY EV converter. Will be real curious to see if he is willing to express any opinions.
 
Here's some wisdom from EV Guru Bill Dube on the EV Discussion List...

I think this is the spec sheet for the cells used:
http://www.s399157097.onlinehome.us/SpecSheets/LVP10-65.pdf

The specific energy is less than LiFePO4, so they were not very
bright in choosing these. They could have picked LiFePO4, avoided the
fires, and kept the battery boxes the same size.

The specs on the GS batteries:
http://www.s399157097.onlinehome.us/SpecSheets/LVP10-65.pdf

I was looking at the photos of the remains for the battery boxes.
There is no thermal management. I also saw no internal disconnect,
but I could be mistaken.

The metal oxide (cobalt, for example) release the oxygen once they
reach a critical internal temperature. Since they have flammable
electrolyte, they have everything they need internally to burn. Like
a rocket. I

LiFePO4 don't have available internal oxygen. They release flammable
electrolyte, and that is it. If you exclude oxygen, they don't burn.
Big difference. If LiFePO4 do catch fire, they burn more like a
couch, not a rocket.

It is not due to simply the energy contained, it is a whole different
kind for fire. You simply cannot put out a metal oxide cell, once it
has ignited.

Bill D.
 
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