Near Battery Disaster

[Mike Cavanaugh]

I recently finished a shoot late one night. The following evening, my wife asked me what the horrible smell was in my office where I keep my gear. By then, the smell had dissapated, and I couldn't really tell the source.

Today I went to pull my camera to get ready for a shoot later this week and found the camera covered in soot. Looking further, I noticed a large hole burned completely through my Petrol camera bag. I looked inside and found the inside compartment where I store spare batteries completely destroyed. Apparently, one of the batteries (from the looks of the damage, a Power 2000 BP-945 replacement) had caught fire, also destroying a Canon BP-915 and a LCD Hood.

The video gods must be looking out for me, because nothing else in the bag (my Canon GL-2, tapes, Rode Videomic, 3 lenses and most importantly, my home and family) was apparently damaged. The camera was within 2 inches, in the same half of the bag as the fire! I think that the Petrol bag was sealed tight, and in combination with being in a closed closet with tightly fitting shelves, there was not enough O2 for the fire to really take hold!
Be careful how you store your batteries and be sure there are smoke detectors near your gear!

Anyone else with similar experience with battery fires?

[Daniel Epstein]

Take these bunch of pictures and contact the manufacturers of the batteries because they may need to do a recall or at least offer you some replacement. Now you know why they are starting to restrict Lithium Ion batteries in luggage for airplanes

[Greg Boston]

I have made this thread a sticky for now... everyone needs to see this and heed the warning. Glad you didn't suffer any major damage, Mike.

-gb-

[Martin Catt]

Did you have the battery terminals covered, or did you just have it tossed in the bag? Canon provides a plastic snap-on cover with their genuine batteries, but none of the aftermarket brands I've bought do.

First suspicion would be a short across the battery terminals. Second suspicion would be an internal short across the charge monitoring board inside the battery housing. The only thing insulating the circuit board from the battery terminals is a piece of cardboard. I could see how vibration could either dislodge or wear through the cardboard.

ETA: See http://www.dvinfo.net/conf/showthread.php?t=119750
Aftermarket battery. The insulator's the white object behind the PC board. I suspect they're all pretty much the same across the brands.


Martin

[Mike Cavanaugh]

I have had 9V batteries get hot in my pocket when a coin shorts across the terminals, so I'm well aware of that possibility. I don't think it was the case in this instance.

I always place the batteries back-to back in the storage compartment and the metal terminals on the Canon style batteries are recessed, so I don't believe that they could touch. The pocket in the Petrol camera bag I store the batteries in is small enough that the batteries don't move around much. The only other thing I had in the pocket was a Hoodman LCD shade/hood. It has no metal, just cloth and velcro.

The fact that the Power 2000 battery was completely destroyed, while the Canon battery right next to it was only charred leads me to think that the Power 2000 spontaniously ignited - similar to the problems with the Dell Laptop batteries recently. I'm going to try to contact the manufacturer and also let B&H (where I purchased the battery) know about the problem.

[Alex Dolgin]

The common wisdom has it that the contacts if shorted can cause a fire like that. The truth is every Li-Ion battery has a safety circuit built in, preventing a short circuit disaster. The circuit is usually designed to trigger at about 3A (depends on the battery size and design), once activated it is reset by a charger.
Most likely the fire resuled from an internal short, either inside a cell, or in connection between the cells. Either of this defects relate to manufacturing quality control issues.

[Mike Cavanaugh]

By the way - the battery in question had not been used in the shoot, but was fully charged. It had never left the bag in the 48 hours previous to the fire.

[Giroud Francois]

got the same problem on a battery pack.
seems the electronic blown (cells were ok).
Ironically , this circuit was originally there to limit such problem.
since i try to store li-ion in metallic case, but when you got 7 laptops, each with spares batteries, 3 cameras, each with spare batteries and some big belt battery pack, you end up
with a big problem.

[Martin Catt]

The interesting point from my battery dissection was that the only thing insulating the battery leads from the pC board is a relatively cheap piece of cardboard tacked between the end of the cells and the copper traces on the board. It wasn't even glued well. I could pull it out with no damage to the paper. No trace of adhesive. If it managed to shift or wear through, then there's nothing between a direct short through the strap terminals spot-welded directly to the cells themselves. Not the most comforting of designs, as far as a safety factor goes.

Martin.

[Mitchell Skurnik]

My suggestion is to put gaff over the bottom of the battery or some blue painters tape. Every time I get batteries from the rental house there is tape over the terminals

[Ben Longden]

On the very day my new AB Ultralight arrived, my old light (using a shoulder bag battery) decided to have revenge.

The charger decided to go "Flambe' and was too hot to touch, and produced an acrid smell. I smelt it before the smoke started..

Ben