KL809 diversion/Li Battery thermal runaway
 

Well done KL crew for handling this effectively... but it could have been a lot worse. Li batteries - an acceptable risk, within the tolerances of safety? Or the next metal fatigue?

https://www.independent.co.uk/travel...-a8346866.html

We are at least five years away from battery tech that can step into a Lion's shoes. While we are trained and equipped to prevent such fires from spreading in the passenger cabin, the smoke can be problematic, if the fire is not quenched quickly. The real threat to safety is batteries carried down below (and of course, the freight boys that haul them regularly).

The ICAO has moved to ban bulk shipments in the belly of passenger aircraft two years ago, but while the Obama administration wanted immediate action from Congress to join the global community on this, Trump rescinded the move, put it on executive hold, allowing US aircraft carriage of these batteries in commercial bulk shipments on passenger aircraft.

A curious move considering Trump's own twittered thoughts on Lion batteries back in 2014:

The trouble with new battery developments is that the driving force is increased power density. That is the opposite of safety. With lithium batteries, the power density is already similar or even higher than some explosives. The time will come when the power storage capacity of devices has to be limited and not just for aviation safety. So manufacturers will have to do more work on efficiency. Maybe future mobile devices will have to be plugged to an external supply to realise their full potential in terms of processing speed and screen brightness. That would be progress :O

The ICAO has moved to ban bulk shipments in the belly of passenger aircraft two years ago, but while the Obama administration wanted immediate action from Congress to join the global community on this, Trump rescinded the move, put it on executive hold, allowing US aircraft carriage of these batteries in commercial bulk shipments on passenger aircraft.

So Trump, in previous utterances, claims to have improved aviation safety since the start of his presidency; a happy coincidence by all accounts, and then flies in the face of general worldwide policy and possibly endangers pax on US a/c. Where have we heard that attitude before?? I wonder if the citizens of USA realise their safety is being compromised by their on chief. And then again; why would he do this? Is there some lobby that has said there is a huge cost increase if Lion batteries can not be bulk shipped by pax a/c? Changes in these kind of policies are often due to money. Or is this being too simplistic?

Cynical Sid maybe built in a circuit that isolates the battery when an external power supply is available so pax on aircraft don't need to run their devices on battery?

airplane mode should reduce maximum charge level to 90% and charging speed. now that would be easy to implement but you run the risk of people switching off airplane mode to get a full charge. still seems like a good idea because people already don't care about their GSM and other phone radiofrequency emissions.
people who are nice which is a bunch will still put the phone in airplane mode therefore reducing charging rate/max charge level reducing the likelihood of thermal runaways.

How about a Wifi frequency detection system in the cabin? No? well it was too easy.

IG

Some posters seem to be commenting on one of three separate scenarios:
a) a phone battery fire in the passenger cabin
b) fire among bulk cargo of lithium-ion batteries in the hold
c) fire in the 787 main battery.

The original post is about a), of which several occurrences have been reported - usually resolved successfully by dropping the offending phone into a bucket (or other convenient container) of water.

b) should not happen if ICAO recommendations are followed. I suppose an alternative solution would be to build in "bomb doors" so that burning cargo, of any description can be dumped (avoiding, of course any schools, hospitals or other socially sensitive establishments).

c) has been mitigated by putting the battery in a steel box, vented to the outside. Two batteries, well separated would provide additional security, but I believe all eggs are still contained in a single basket.

Correction, the battery system was completely redesigned (although still using Li technology) with better control of the battery charging along with better isolation between cells (to prevent a single cell failure from propagating to the adjacent cells). The steel box provides additional protection to contain any future battery failures. Last I heard, there had been one battery failure since the redesign, it contained to a single battery cell.
The 787 has always used two separate battery systems.

So, in one corner of the ring, we have approval for ETOPS 180 or even more on the aircraft (just my assumption for KLM 777)
and in the opposite a diversion because of a single passenger's phone thermal runaway.

I do not understand this sport. More importantly: where was the bucket? :sad: But perhaps we are not hearing what actually happened - the chances of that are about what, 86% ? :E

Stay safe and do not let the beancounters remove the fire gloves from the cockpit.

Being a proper, civilised, grown-up, full-service European airline, KLM still serve champagne to revenue-generating pax in the front; and that champagne sits in an ice bucket. Maybe that was the one?

Long time lurker - first time poster. Although mere PAX and a frequent user of various European airlines due work, one thing I always find alarming is the practice (mainly on LoCos) of tagging cabin bags for the hold at the gate - whenever I witness this I seldom see any effort from gate staff to check whether any potential Lion nasties are removed from what is now effectively checked baggage. If something similar to what befell KL809 above, was to happen in someone's checked bag, couldn't the results have been far worse? Sometimes I wonder if this isn't the 'next big thing to go wrong' and whether it will take the loss of 000s of lives before something is properly done.

There's more to this than energy density...A typical candle that you might put on your dinner table stores more energy than a stick of dynamite, but the rate at which it can deliver that energy is limited. Batteries with a huge energy storage capacity are not inherently dangerous, until they try to deliver all of that energy in a hurry, in which case they become extremely dangerous. Rate limits can be imposed by circuitry external to the battery itself (the simplest example being a fuse), but that doesn't address the question of internal malfunction. The safest batteries would be ones in which the internal chemistry somehow imposed an inherent limit on the rate at which the battery's stored energy could be delivered.

Why do you think ETOPS is relevant? If you have an uncontrolled cabin fire and you're 180 minutes from an airport, I don't think having more than two engines is going to make much difference...

Cabin luggage in the hol
 

Had this happen ten days ago. All our cabin bags were tagged to go into the hold. I asked the ground crew: shouldn't we remove laptops etc? She looked at me sheepish and said, yeah, well sure you should.... So we were the only family stepping on board with our hands full of laptops, phones, loose li-ion batteries (I put them in a special plastic holder so they can't short), powerbanks, mobile speakers etc. With the five of us that's quite a big load of battery power that's not allowed to be in checked bags but was going to be put into the hold anyway. It didn't make me very comfortable on the flight.

​​​​​​Genuinely surprised more isn't done about this..maybe I'm over estimating the risk but be interesting to hear what crew think

I just checked with my newish Xiaomi 4X. I activated the airplane mode and by using the company charger it went to 97% and that because I unplugged it. And ISTR that using the airplane mode it charges in less time - not sure if the charging is faster or much less energy is used from the mobile. However the temperature of the mobile did remain on the cool side.

i should have stated more clearly that i was proposing a feature to reduce the likelihood of a thermal runaway.
no phone i know of has the mentioned features implemented.

don't really know what the cirumstances of these thermal runaways are, maybe it's just using the device so modifying charging behavior would not even help.

Regarding runaway thermal events, there is unfortunately no amount of electronic control nor digital sophistication on the outside that can stop the sudden internal short circuits that are the hallmark of these lithium battery failures and fires. The battery structure itself requires a redesign. For now, better manufacturing QC is the focus.

The official line is to ensure a steady supply of Li batteries to "remote areas" for "medical devices" etc which seems a bit far fetched in the overall scheme of things considering if a passenger aircraft with room for substantial belly cargo can get there, so could a freighter (or a truck). Perhaps Trump's choice of ignoring the ICAO is simply contrarian, his logic being "if Obama wanted it, it must have been bad" - reality be damned.