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Electric Stunt => Gettin all AMP'ed up! => Topic started by: Andrew Borgogna on July 30, 2012, 03:12:20 PM

Title: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: Andrew Borgogna on July 30, 2012, 03:12:20 PM
I was doing a really dumb @$$ move today and got some minor burns to prove it.  One of the balance wires pulled out of a battery I had, so (read dumb @$$ move #1) I decided to cut the skin back and see if I could reattach it.  As I was walking through my house the battery went off like a Roman Candle.  It seems that the Xacto knife I was also holding (Dumb @$$ move #2) poked into the battery and bad things happened.  I know this is what happened because the tip of the Xacto knife is black and burned. 

I got the battery out of the house before anything bad happend other than some very minor burns on my hand.  It sure scared the hell out of me and my wife's cat.  The battery is now sitting in the yard far away from anything that can burn.  It will stay there until I am completely sure no more bad things can happen.

Let the flaming begin, heaven knows I deserve it. HB~> HB~> HB~>
Andy
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: Tim Wescott on July 30, 2012, 03:27:16 PM
Let the flaming begin, heaven knows I deserve it. HB~> HB~> HB~>

Uh, I thought the flaming was over...

Chuck that thing in a bucket of salt water & let it sit for 24 hours.

Or better yet, Google on "Disposing of damaged LiPo batteries" or some such, and see what it comes up with.

I would criticize you, but then I'd have to fess up to all the incredibly dumb things I've done lately, and explain why I shouldn't be criticized for them.
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: Bill Little on July 30, 2012, 03:39:10 PM
Hi Andrew,

No way I can "flame" you since I have done some really stupid things over the past 50 years of flying toy airplanes!   And I haven't had very much to do with the batteries, yet, so the jury is still out on what stupid things I can STILL pull off!!

Glad no lasting damage was done to you are anything else.

BIG Bear
RNMM/AMM
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: John Hammonds on July 30, 2012, 05:29:24 PM
Yup, me too.  :-[

One thing which I have found repeatedly is the shrink wrap around pack forces the leads into such a position that they just won't "Quite" fit into the fuselage. In this case I usually trim the shrink wrap back around where they exit the pack until I can "Fold" them back along the pack. (I know how this all sounds now). Once (And once was enough) I trimmed them while holding them in my hand. Never again. Still not sure what happened (Other than I obviously pierced the pack). It all happened very quickly, fortunately I was outside and dropped the pack, no burns but shook me up a lot. The financial loss paled into insignificance while I was counting my fingers.

TTFN
John.


 
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: Dennis Adamisin on July 30, 2012, 05:53:26 PM
That sounds like running in the house with scissors (not that I know anything about that)  Glad to hear you & house are OK.  Cats are tough too. 

QUESTION ABOUT THE SALT WATER BATH:  It would seem that this will only work if the casing of the lipo is pierced?  Is this a case of first driving a wooden stake through the lipo's heart?  (I HATE vampire movies)
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: Tim Wescott on July 30, 2012, 06:59:22 PM
QUESTION ABOUT THE SALT WATER BATH:  It would seem that this will only work if the casing of the lipo is pierced?  Is this a case of first driving a wooden stake through the lipo's heart?  (I HATE vampire movies)

I dunno -- it's from an article I read ten years ago or so in FM or MA, or maybe Silent Flight, when LiPos were just getting popular.  Which is why I suggested Googling, 'cause the information is old and may not have been right even then.

I have done it, and it does seem to discharge the battery.  Putting the whole shebang under water means that if the pack does go off it's in a medium that's going to deny any fire enough heat to do any damage.
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: dennis lipsett on July 30, 2012, 07:06:38 PM
My knowledge of Lithium and Sodium is that they will burn in water as water has Oxygen in it. nasty stuff. If you don't want a fire then you have to put it under something that won't feed it.

Dennis
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: Wynn Robins on July 30, 2012, 07:07:56 PM
yes you have to pierce the case or it doesnt work.....

I put one in a bucket of salt water without piercing it and after a week it was still almost fully charged.....I thought it would short out - but it didnt.......WEIRD man - just plain weird.

And Andy - i once touched both wire with my soldering iron (without realising as I melted through the heat shrink on the previosly soldered terminal)  that made some nice sparks!!!!  

Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: Andrew Borgogna on July 30, 2012, 08:05:57 PM
Well I did the salt water thing and the cell that was pierced produced all kinds of nasty stuff.  There was bubbles coming from both the main wires and the balance connector wires.  Anyway the battery is sitting my my block wall waiting for disposal.  I got to admit I like Denny's idea about driving a wooden stake through its heart.  Man when these things go off, it can be scary! Check out the pictures I am including of the battery and what it looked like in the salt water.
Andy
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: Larry Renger on July 30, 2012, 11:52:37 PM
Double, double toil and trouble, fire burn and cauldron bubble, eye of newt, ear of bat, Lipos burn, and that is that.   LL~
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: john e. holliday on July 31, 2012, 08:29:22 AM
Well Andy, I see you are still learning things.  Glad you and everything is okay. H^^
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: John Cralley on July 31, 2012, 10:18:07 AM
Andy,

If the Deans plug still shows voltage, you might try plugging in an old ESC and let sit for a day or so. The ESC will gradually bleed off the battery until it is dead (don't ask how I know this!!). I don't know if it will still catch fire if you puncture the dead cells that are still intact (maybe that would be good to try  ;D or NOT).

John
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: Andrew Borgogna on July 31, 2012, 10:59:30 AM
John
The battery connector is totally corroded from the electrolysis.  This thing was bleeding electrons while in the salt water, my wife the chemist said water was being converted back to hydrogen and oxygen hence all the bubbles.  The bubbles were coming off the main connector and the balance connector.  I got to believe the salt brine was conduction electrons or there would not have been electrolysis.  But I am the dumb one in the family, thank God my wife is smart and beautiful and as Doc will tell you she can bake cookies with the best of them. y1
Andy
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: John Cralley on July 31, 2012, 01:47:35 PM
Wow Andy,

A wife that is smart, beautiful, and bakes cookies!!! If she does windows too she is a keeper!!!  y1

Heck, I bet she is a keeper in any case!!!   ;D

I would guess that the cells are dead given the salt water acting as a conductor. That is probably the rational for soaking the battery in salt water. Now is time to get out your nail gun and fire a nail through the battery to see what happens.  #^  S?P   Nail it to a board and get out your marshmallow fork (or just use an old coat hanger) in case you get a nice fire.  VD~
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: Larry Renger on July 31, 2012, 06:47:22 PM
"I got to believe the salt brine was conduction electrons or there would not have been electrolysis."   Why do you think the salt was specified?  Pure (distilled) water is an isulator!
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: Andrew Borgogna on August 01, 2012, 12:55:28 PM
Yes Zen Master.  I have so much to learn.   ::)
Andy
Title: Re: Do not stick a Xacto knife into a LiPoly battery. Duh!
Post by: john e. holliday on August 02, 2012, 08:58:46 AM
Not only does Andy's wife make great cookies,  she helps take planes from the circle and is good looking.   Andy has a great one there. H^^