I was distracted and didn't check the cell count and lost lipo battery. Fornately I charge them in a fireproof safe and saved my workshop and house.

I smelled a sweet smell and I turned to the safe. Just then the smoke poured out the slightly open safe top. I diconnected the battery from the charger and shoved in the connector and locked the safe and just after that another puff of smoke.

After it was all over I opened the safe outside there was only charred and burnt cells.

My mistake but by using a fireproof safe I saved my bacon.

I use a ASTRO 109 but the battery must have been fully chqrged and as a result miscounted the cells .

John F. Clarke

BE SAFE VERY SAFE.

I have a battery bunker and a fireproof safe, but I use the battery bunker for charging and storing batteries when I go to the flying field. Does anyone know if the battery bunker (ceramic container) does a good job during a Lipo fire?

Thanks,
Glenn

I would say that the fact the lid was closed it contained any fire if any. That being been said if the well is deep enough any fire will go up and most likely not hurt anything.

You can be rest assured I will use the safe each and ever time from on. In fact I always use the safe, however this time I was distracted and doing two things at a time and it cost me.

John F. Clarke

What size and cell count battery was that? And are you talking about the $18 Sentry firesafe?
Thanks!

I use a Brinks box for keys (about 6"x6"x3") as a charge container but after reading some of the tests on various containers plus this thread, I know deep down I should get something more substantial.

I charge in a safe that has the key lock removed. I run the wire through the opening.

The problem I have is that I do not want to store other cells in there while charging in case I do have a problem. I would hate to ruin hundreds of dollars worth of batteries. I guess I'll have to get another one for storage.

Tim

Double check your 109 before using it again. I had an IC fail on mine and it sent the power supply DC directly to the battery, doing it much harm.

It would look a little like it was charging, but the charge voltage was the same as the power supply voltage reading before you plugged in the battery.

Because I am paranoid, I charge and transport lipos in a $18 Sentry 1100 fireproof safe, aka "Arm Stretcher".
It is good to know they work as intended.
Sorry to hear of your loss but glad your house is still there.
Crash
P.S. About 2 hours ago I dropped a 1S4P 7.8Ah stack in salt water to neutralize them. One cell was punctured in a crash - that pack rode home inside the fireproof safe by itself! One electrode immediately started streaming bubbles as the electricity passed thru the salt water. And bigger bubbles are still streaming out of the punctured cell! Tomorrow I should be able to flush the contaminated water and toss the neutralized cells in the trash. Ouch! $$

Originally Posted by JohnC

I was distracted and didn't check the cell count and lost lipo battery. Fornately I charge them in a fireproof safe and saved my workshop and house.

John F. Clarke

BE SAFE VERY SAFE.

I am SOOOOOO glad you posted this, sorry about your pack but glad to hear the firesafe did the job.

I had Li pack explode about a year ago, I was not too smart about charging, and set the wrong (manual) cell count in my Li charger. Resulted in a fire in my hobby room. Picture of cell that blew is attached. Since then I have religiously kept my Li packs in a "firesafe" and have always wondered if the firesafe would contain an exploding pack....

Thank you - thank you for posting the results of a real-world experience.

Originally Posted by glennhl

I have a battery bunker and a fireproof safe, but I use the battery bunker for charging and storing batteries when I go to the flying field. Does anyone know if the battery bunker (ceramic container) does a good job during a Lipo fire?
Thanks,
Glenn

See post#7 here



Charles

Originally Posted by JohnC

I was distracted and didn't check the cell count and lost lipo battery. Fornately I charge them in a fireproof safe and saved my workshop and house.

.

Thanks for the report John. You are the first to my knowledge to have an unplanned lipo fire in a safe. As such, we would be very interested in the size of the pack. 3s2000? 2s2p4000? 3s600?

Ok it was a 2 cell 1500 Kokam pack and was in a small First Alert firesafe. I take all the packs out of the safe and only keep the cell being charged in the safe. That being said I believe I had checked to see if it was reading correctly and I did so as I noted in my log with the voltage. I log every pack I use. What plane, what pack number, charging current, starting voltage. At the field I note the temp of the pack and the motor after the plane has landed. I like the fact I can get a running idea if a problem is occuring or not with my planes and how many times I have used a pack.

I now believe the problem was caused by a voltage tranient or momentary power drop that caused the cell miscount to happen between stage 1 and 2. I use the Astro power Supply and I had charged a number of cells since the problem occured without any problems. Perhaps a change can be made to halt the charging process if a tranient happens or surge.

Thanks for posting and happy I have helped some people. I try to be safe but.... things can still happen.

John F. Clarke
AMA 9473

Thanks John - That's a good data point.

OK,

What do your store and charge 10S3P cells in? The Brinks type portable boxes you can buy here in the UK won't hold even one of these large packs and I need to store and transport at least 3 plus all my other smaller batteries.

Malcolm

Old pressure cooker is not bad with holes for the wires and for venting in case of fire...

GF