LiCoO2 reacts with the electrolyte above 130°C and decomposes approaching 200°C, giving off oxygen in the process.
My understanding is that any oxygen recombines with the anode material as it is produced, with heat and non-combustible byproducts; if the anode is graphite, which I conjecture is the case, that would be CO2 for a large part.
Any good sources on the exact chemistry in the battery, and how it degenerates in case of thermal runaway ?
Also, independently
(2) Design of the lithium ion batteries must preclude the occurrence of self-sustaining, uncontrolled increases in temperature or pressure
(..)I do wonder how they're going to get round this provision: either the FAA will have to retract the offending paragraph or Boeing will have to use a different type of battery. I suppose the third way will be to argue "we don't know what caused it but we've changed lots of things so it's OK now"; depends on how much spine the regulator has that morning(..)
This is from
http://www.gpo.gov/fdsys/pkg/FR-2007...df/E7-8186.pdf
Any advise on how this could be worked around by Boeing from a legal standpoint? Especially since the
design of the cells remains apparently unchanged (only their testing is), and experience has proved that self-sustaining uncontrolled increase in temperature is a real possibility.
Edit: Perhaps
uncontrolled is a solution: now that there is the fire box/enclosure, any self-sustaining increase in temperature or pressure is arguably controlled. Or perhaps Boeing can waive the special conditions and re-certify according to general rules.