We carry both a glove and a bag. If the battery does go on fire or start to smoke you will probably burn your hands badly if you try to throw it out withoutthe glove. At the same time the heat will pass through.the glove quickly if it reaches melting point, hence the bag.
Although for portable devices we tend to have a rule.of having it charged over 70% before any flight.
Peter wrote:
Posts moved to existing thread.
Sorry, I did a search first, but probably lacked patience (likely because I have to much time at hand!!). Thanks for redirecting it.
Doers anyone have any reccommended lithium fire bags for ipad sized items?
Thanks
An iPad sized lithium fire bag…🤪
I got this from Amazon.
I see these cheap ones along with some worth between 500 and 1.000 euros, so wonder whether the cheap ones are any good.
At that price, maybe worth testing one by setting an old phone on fire. May be educational.
Where are the 1k priced ones?
These bags exist primarily for the electric model plane business. Those batteries have no protection and the charging tends to be primitive e.g. no cell temperature monitoring. And mechanical damage is quite likely to set them off, and they burn really well (plenty of videos out there).
If you crash a LIPO powered model plane, there is a fair chance of a nice fire but it will be too late to use the bag 
But there seems to be a greater awareness of LIPO fire risk there.
A fairly big current risk seems to be e-bikes. They seem to combine the best ingredients:
Fire services report a lot of calls to e-bike fires, and it is always too late to save the bike.
One also cannot avoid in-flight charging of a tablet, except on very short flights. This takes us back to here where is seems clear that unless you are running a 10 year old (and low-performance) Samsung tablet, you need a mount with built-in fans.
This is an interesting read, claiming FAA certification is bogus..:
https://www.gleimaviation.com/2022/08/30/lithium-ion-battery-fires-and-containment-bags/
Where are the 1k priced ones?
OK, not quite 1k but maybe with shipping they would be 
claiming FAA certification is bogus
No surprise… portable equipment, how could it be?
Historically, portable equipment would need some kind of approval if it was mandatory-carriage. So e.g. an O2 system needs approved parts if it is in an AFMS – basically in most turbo engined planes, and that also leads to the max 18k cannula altitude and a mask above that. But a plane without a fitted O2 system has no such limitations.
So a certified lithium bag would be relevant to where it is mandatory-carriage. Probably on an airliner?
