Your points are interesting, Freckly, but the issue here is personal responsibility as Ed's Dad has so carefully said. There are lots of products on the market that are tested to within an inch of their lives. Everything from aircraft to the humble toaster is tested, yet things still go wrong. The issue is what are you doing to make sure that risks are mitigated or avoided, not what someone else is doing.
If you are worried about using LiPos and 'untested' products then I suggest you find another hobby. Distributors and importers state on their products exactly what they will and will not do, so none of this should come as a surprise to anyone. Never, anywhere has anyone claimed that LiPo sacks will contain the fire absolutely. As Ed's Dad says, without the sack the risks were higher.
May I point out the error of fact in your last posts? LiPo sacks do not claim to contain debris or to spread debris. They simply claim to be able to hold a LiPo during charging and that doing so reduces risks. This is true for both types in the fires we have. Our experience is that one type does it better than the other. Since no degree of containment is claimed, no degree of performance can be deduced from the manufacturer's description. Please state your evidence that these all these containers are made in China - I have not found anything to support that.
There is no evidence that these incidents were caused by charging issues or charging above 1C. The problem is that once the incident occurs, one of the first casualties is the charger and the second thing is that it is usually disconnected by someone in the false belief that this will stop the fire. Once the incident is over, the information the charger might give us is lost from one of these two causes.
(Another tip - don't waste any time disconnecting the charger. A LiPo fire is a thermal runaway caused by the burning of the lithium. When it starts a short circuit inside the battery is inevitable at which point the charger is doing nothing to help or hinder the incident. In some case that sort circuit might blow a fuse in the charger, or damage its internal circuits. Lithium reacts with oxygen, so once started the fire is self-fulfilling. Until all the lithium is consumed, or the oxygen supply cut off (hence the sand) the fire will not go out on its own.)
If you would like to set up a qualified testing regime please go ahead. Otherwise we cannot reasonably test these products since we do not have a qualified set of circumstances that they are supposed to be tested against. I am sure that distributors and manufacturers would be pleased to accept your results providing they were scientifically researched and carried out.
I appreciate what you are trying to achieve here, but your posts are not in the least helpful to those of us trying to get the right advice to racers. Assumptions are useless and most unhelpful, bad facts even worse. It is not the manufacturers, distributors, retailers or BRCAs problem, it is our problem and we as users have to deal with it ourselves as best we can.
Xtreme - like you we have no evidence that leads to the root cause of the fires we saw. Like you both were using chargers that were not at the bottom end of the market, and like you the cells were of good specification from known manufacturers/ distributors. As stated above, any help from charger settings were lost when the incidents (and not a small quantity of sand!) wrecked the chargers.
My only clue to what might be happening was unearthed during the Sony/Dell/Apple computer fires of 2006. During that investigation it was revealed that the manufacturing process cannot prevent tiny metal fragments being in the lithium/polymers. It was speculated that if these migrate when the batteries get warm, they can puncture the separators and short circuit.
I stress I have no evidence for this but it does fit with the random nature of these incidents. We are pushing things way beyond a simple domestic-usage cell. Even at 1C we are charging modern cells at 6A to 7A!
We still cannot say what causes these incidents, so we have to mitigate the risks. LiPo pouches are the best means we know at present for charging at the races. Storing in a ventilated tin at home helps with any storage concerns. Making sure your charger is on a LiPo program with the right cell count and charge rate before you start charging, as well as closing the pouch as well as possible, all reduce risk. Finally, make sure you know where the sand bucket is.
I hope Ed gets better soon and is not put off our sport. If you do find out anything more about your incident I would be grateful if you could share information.
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