@ Turin...Yes, I understand that in an emergency, you MIGHT want to pull the last dregs out of the MAIN battery....but isn't that why it carries 2 apparently identical units?
Even allowing for the extra cost of certifying these units, they really don't come into the realms of "disposable"...at the price, I suggest that , presently,(grounding excepted) the saving on fuel and space has been wiped out several-fold by the sheer cost of these constant swap-outs
At a couple of thousand dollars each (still a lot of jet-fuel) I'd go along with it.
BUT they're tens of thousands of dollars a pop and at that price, if I were a "punter" I.E. a Boeing customer, I'd expect my Lithium batteries to be effectively managed to give me COST-EFFECTIVE Emergency power
It's not beyond the wit of smart engineers to design a proper, effective battery-management system,possibly with automatic sensing to accass that final, destructive reserve of energy.
It hasn't been done and I'd imagine the owners of these White Elephants feel well and truly shafted......save 20% on fuel, but spend multiple times that on batteries....free Russian Roulette every time your pilots switch on....will it work or will it burn?.......Yea! brilliant sales-pitch....NOT.
I'm with the majority of the last few posters.....faulty management...both in Boeing and in the Battery-system.
I've been saying it all along,- modellers have been using lithium cells for a long time now, they have fires, cell-failures and crashes...but you have to be careful playing with a 2-metre diameter flying scythe and I'm certain the lithium cells have had a lot harder use, with a far longer time between failures than the Thales item.
These modellers are NOT professionals, but they understand the care of their motive-power and subject them to very heavy currents-by the nature of R C helicopters, EVERY cycle is using the maximum safe capacity.
If they can do it,as hobbyists, why can't the might of Boeing, Thales and Securaplane , manage a "floating " emergency battery and an APU starter-battery. Even making the (probably wrong) assumption that the APU is used at every start to give start power for the main engines, there's still the pushback, engine -warm-up and taxiing times for the APU battery to recharge.
To suggest that it's not possible to operate this battery well within it's safe operating parameters is codswallop.
defective management (human and charging/monitoring.
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