I got another reminder how potent these packs are, fortunatelly in my household it is a "LAW" to charge all lipos outside in safe enviroment. Almost brand new pack '4S/5000/50C' with no sign of swelling badly puffed up during charge at only 1.6amps. After quick disconnection and placing it on pavement it exploded just as I was going to pick it up and chuk it in bucket of water. It shot 4 feet high jetstream of flame for 4-5 sec. and continued burning. Hate to to think about result if it happened indoors, Joe.

This is not common and either the pack had a problem or it was not charged correctly. I have test failed many battery packs on purpose, to destruction, and I know it takes a lot to get one to go.

Was it new?

To begin with why was the initial charge rate 1.6A? It should have been set to 5A, a standard 1C setting.
Your using bullet plugs, are you sure you had the polarity correct at the charger and pack?

Just curious, who makes this pack?

You got lucky this time for sure. You should charge in a metal container or a LiPo Sack and have easy access to the cables at all times.

I was wondering the same thing. This pack should be charged at 5amps which is 1C. I have no knowledge if charging at a lower amp would cause problems but I was always taught you charge a pack at what it's designed to be charged at.

Likely had charger in wrong setting. Perhaps a higher cell count charge setting in other than balance mode. Had a similar event caused when charging a 3S battery and charger set to 4S. Wouldn't have happened if I was in Balance mode.
Ever since I always use balance mode to reduce chance of error.

This area looks suspicious to me. Maybe some impact damage that didn`t look bad on the outside, had shorted out the layers. Cells that are just over stresses usually fail over the whole cell and not at just one point.

Hi Jofro! First, glad you and yours are ok!

Next, lipo's have lots of potential as, you have documented. I have yet to have one go off for NO reason. That being said, I have had bad lipos direct from the factory, bad soldering or bad assembly. Usually, these lipos give some type of warning. Anyway, user beware and glad your ok!

Michael (if your not fryin, your not tryin!)

I'm with Knife, something fishy here; I too noticed what looks like a cut in the pack that has been circled in red.
This story sounds too incomplete and dramatic. (Like Chris Nicastro I have test failed or otherwise purposely abused quite a few packs and have NEVER had a "4 foot high jet stream of flame") ......,,,they puff, they vent, then smoke, then burn.....and leave a lot of residue (which residue I do not see in the picture by the way)..

Just my observation

Something is fishy with that picture indeed. And please use proper safety procedures when charging.

I have a theory,

lipo had damage across 2 cells.
voltage was below safe limits to balance charge
Stuck the charger on nicad/nimih settings to try to bring them back up.
without watching it carefully, you end up with the above pic.

Just a theory.....

Originally Posted by Knife Liddle

This area looks suspicious to me. Maybe some impact damage that didn`t look bad on the outside, had shorted out the layers. Cells that are just over stresses usually fail over the whole cell and not at just one point.

4mm bullets on a battery? Why

I use bullets on all of my packs so I do not see a problem.

I have done quite a bit of testing lipo packs at work and the only way I could get a 4 foot flame was to pierce the pack with a sharp metal probe to fully short out the packs. (do not try this at home, it was done in a controlled environment)

So yes some could claimed that this thread is not up to snuff. Somebody my be trying to get get attention.

If chargers are properly used with balance tabs most lipo accidents would be prevented.

Everybody makes mistakes and very seldom will accept the responsibility for the actions. (Believe me I have made plenty of mistakes)

Originally Posted by Xflyfun

Attachment 5426583
4mm bullets on a battery? Why

Nothing wrong with that if you use it within tollerance. I've used 4mm a bunch of times without problem. Even in higher amp instances. Not to say 5mm isn't a whole lot better.

Originally Posted by jofro

After quick disconnection and placing it on pavement it exploded just as I was going to pick it up and chuk it in bucket of water. It shot 4 feet high jetstream of flame for 4-5 sec. and continued burning. Hate to to think about result if it happened indoors, Joe.

Joe, was it similar to this?

Lithium Polymer Cell - Catastrophic failure (1 min 35 sec)

Originally Posted by bzfrank

Joe, was it similar to this?

http://www.youtube.com/watch?v=5J96ywv7yAM

All this does is sensationalize a very unlikely scenario. Look at what you had to do to make it do that.

Hi Guys, idea to load up my Thread was to make people more aware! We could analyze why it happened FOR EVER AND EVER. I had the same scenario happened inside my shed few years ago, thanks to my alarm system I managed to stop the fire and totaly changed my approach to handling lipos, Joe.

Originally Posted by jofro

Hi Guys, idea to load up my Thread was to make people more aware! We could analyze why it happened FOR EVER AND EVER. I had the same scenario happened inside my shed few years ago, thanks to my alarm system I managed to stop the fire and totaly changed my approach to handling lipos, Joe.

This has happened to you twice now?
Best evaluate the "change your approach to handling LiPos" again

Touch wood, I guess I have been lucky, never yet had a LiPo go off unintended.......
-Mike