Well I had my first LiPo mis-hap. Blew the pack right apart...my fault, but no damage done.
I've been using LiPos since about 2004ish.

This was a partially charged pack from last season. I put it on my Astro charger to top it off. The charger first thought it was a 3cell pack (Which it was), but apparently switched to 4 cell. With this charger you are SUPPOSED to stick around and check to make sure it stays on the number if cells where it is supposed to on a partially charged pack. As this has never been a problem before, and since it was my first time out this year, I kinda forgot. We were all sitting on a bench about 20 foot from the thing, and heard what sounded like a muffled shotgun. We all immediately looked over, and I paid particular attention to my charging packs. No smoke, no flame. Nothing. Curiosity got the better of me so I eventually walked over. That's when I discovered the blown pack. I grabbed it and tossed it in the gravel turn-around. It hissed like mad, and balooned up, but never really got all that hot. After it was done with it's hissey fit, it was back to normal....well except for a hole blown out of the side of it.

Ended up being a blessing in discuise. The pack was about 5 years old and I use it in my Cularis glider, well used to. Climb was pretty decent, about a 35 degree angle, and took about a minute to get to altitude. Well since that pack was no longer usable, I put in a newer pack. It is a bit lighter so the CG is back a bit, and apparently more powerful. Now it climbs out at about a 65 degree angle, and I was at my normal altitude in about 20 seconds. The slightly aft CG also made it react better to lift. WIN, WIN, Loose ( the lose was a blown battery) Apparently it was well past time to replace the pack. Just glad no damage was done. Attached files

 

Normally this is not the case. BUT still I NEVER charge my batteries in the house, or even store them in my house. In all the years I have done this, and all the countless packs I have charged this is the first incident I have had. It still makes me cringe when I see someone charger their packs in the back of their cars, or under the hood; even more so now. Actually right after my pack blew up, a flying buddy went and hooked up two 4 cell 5000mah packs up to charge under the hood of his car....

This case was with an Astro charger. It was one of the first LiPo chargers; actually the one I have was a Nicad charger, that I swapped out a chip to make it a LiPo charger. It will auto sense the number of cells, and charge accordingly. No real safety features like the modern chargers have. I have used this charger since 2004ish with no problems.

The issue this time was I attached a partially charged pack as I put storage charges on my packs at the end of the season. It is a known issue with the Astro chargers that in some cases a partially charged pack will initially show the proper number of cells, but a short time later, it will bump up the number of cells by 1. I'm certain this is what happened as when I put the pack on the charger, it said 3 cells... As it was the first time this year that most of us were out at the field, we had a lot of catching up to do so to speak, so I forgot to check and make sure that the charger was still at 3 cells. After the incident, the charger said 4 cells, and had an over voltage error.

 

Pickpockets also frequented the crowds who gathered to watch men being hanged for pick pocketing.
Some people just have to learn the hard way

I used to use a Pyrex dish for charging. But now I use a safe to charge my lipos in and that seems to work good. After seeing one go up you have a greater respect for what they could do.
Mark and Trish