What amazes me is that Boeing admit that they still don't really know what caused the problem and in the same breath, say they've fixed it. Classic cognitive dissonance.
Well... "ish". They never said they "fixed" it. What they have said is that when it happens again, it will not take the aircraft down.
I suspect that all of the engineers who understand Lithium-Ion technology "know" what the cause is, but they cannot PROVE it because the occurrence of the problem vaporises the evidence.
I suspect that everyone believes that the proximal cause was dendrites on the battery electrodes. These can occur spontaneously: the root cause may very well be "choosing Lithium-Ion batteries".
We and everyone else could guess that the dendrites were caused by high charge or discharge amperage. But they can occur simply through cycling the battery. Whatever: by the time thermal runaway occurs, the original dendrites have been vaporised long ago.
OK, so the Boeing 787 becomes the first form of locomotion since steam trains to have a fire-box!
Now we have some questions for the Flight Crew among us.
Whether the batteries in their fire boxes are on fire or not, they are not producing electricity. Just above them are the same type of battery that provides the 10-minute backup of last resort for the flight controls. Those batteries are apparently not getting fireboxes.
So: If you were in Sully's position -- both donks failed and APU not running -- are you safe enough? Can you get us back on the ground undamaged?
