As mentioned in a recent newsletter, an electric heli crash at the field saw all the smoke get out of one of those dang LiPo batteries again. Among those present, was an innocent bottle of salt water, brought along specifically to battle the aforementioned smoke. And it did.
Unfortunately, it also ruined most of the electrics in the grounded heli, which subsequently required a major overhaul.
There are plenty of warnings around for LiPos and WPMAC has two metal boxes for charging these tempermental things, which must be used if you are charging LiPo batteries at the field.
Due to their chemical makup, LiPo batteries can go short circuit internally if overcharged, or overdischarged, and it's for these reasons and their potential to generate heat when they do go short circuit, that they have such a name for themselves. But I'm not telling most of you anything new.
This warning serves two purposes. To raise an awareness of the dangers, but also to point readers to some info about what to do in an emergency. ie After crashing a LiPo powered model. I would suggest the following.
First - do now throw salt water over the model. A fire extinguisher should be used - refer to our emergency management plan for the recommended type.
Remove the battery from the model. Precautions should be taken as a damaged battery could burst into flames. If you have to cut wires to remove a battery, do not cut both positive and negative at the same time. Not not put a crashed battery into your car for at least 10 - 15 mins after an accident. Let the battery cool and stabilise. If its bloated, punctured or has other obvious damage, consider it terminated. Dispose of as per below (this is where a bucket of salt water will come in handy).
The following article has the best description of LiPo disposal I've read. http://radiocontrol.wikia.com/wiki/Lithium_polymer
Dropping the battery into salt water, will also discharge it but whether the terminals corrode before the battery is discharged is anyones guess.
The above information is by no means a complete list - always follow your battery manufacturers instructions.
Some more infomation about LiPo use can be found here
