A long time RC'r. Excellent builder, good, safe pilot. Guy got into electrics a few years ago. The fire started in the hobby room. House was fully involved when the trucks rolled up. A friend who works for the Fire Department told me it was an L-Poly battery explosion. Cost him a 400K house and everything in it. They just barely made it out of the house with their lives. Be careful with that stuff.
Best thing to do is get a tiny fireproof safe. Then charge and store the Li-Polys in there. Those safes are a $10-$15 item from Walmart. Well worth the small investment.
Wiz
Bill wrote:
If this is true, I feel very badly for the man. For this to happen, the batteries would have have to been damaged or charged improperly. On top of that they would also have to be unmonitored and NOT in a fireproof container. It doesn't sound like he was being very safe IMO, unless there are some very unusual circumstances here.
Frank I assure you, it's a true story. He has been using these batteries since they became available. Knowing him, I get the feeling that he probably plugged the pack into the wrong charger and went to bed. The fire happened in the middle of the night. He was fully aware of the safety issues concerning these batteries. As far as I know, he had a fireproof box. I will find out more details later.
I bought a couple of these, and I have a problem with that method. One way of turning a fire into an explosion is to confine it. Although the covers are not tight, I worry about multi-cell packs generating enough force to blow the lock and hinge apart. My pack is 18 1500 mAH cells, and I will soon have three of them.
Just for grins, I drilled a 9/16 hole through the top of one and installed a cardboard tube used by Great Planes as a wing screw guide. Applying a shop vac to the hole did convince me that there is quite a bit of leakage around the edge of the closed top, but - is it enough? Any better ideas?
I am seriously considering a test using the drilled safe with wires going down the paper tube to overcharge the pack, and sealing the tube with silicon seal. (One pack got severely over-discharged, and the only thing I can think of to do with it is use it as a test article.) However, if someone has already done this, I would rather not.
As far as charging at home - I will charge an 18-cell pack in the fireplace with the damper open and a metal shield between the battery being charged and the screen and doors on the fireplace. I plan to leave the pack unattended or at least not closely attended while charging.
-- Mike Norton
I got a bit of a warning myself not long ago - I put a tiny (230 mAh), brand-new LiPoly on the Potensky, then went about my business around the house. Later, I realized I'd better check on it before I went to sleep and returned to find it completely ballooned out, much like a pan of Jiffy-Pop.
I had failed to configure the tiny dip-switch charge block for a single cell, from my usual two-cell pack. I became complacent about charging, since the charger had worked fine on the two-cell pack without incident for years...
I was afraid to get near the thing to unplug it.
Dan.
These things can be scary. I have seen some new charge limiter devices being advertised for about 25 bucks. Might be a good investment.
Geez. You guys got me thinking it might just be best to chrage them at the field only.
Think how mad your buddies would be if you burned down the flying field!!!! ;-)
Good flying, Bob Scott
We may need to bring back the back yard bomb shelters they were pushing in the 60's as a place to charge our lipo's! :-)
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