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Shorted lipo! Now DEAD


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Well, I finally did it, and shorted out a lipo, only for a fraction of a second, but now its showing as totally dead..

 

I put it on the battery meter, and nothing, no power at all, battery meter doesnt even come on.. Tested the meter with other Lipo's and its fine.

 

I will say too, I did this testing a custom made switch setup for my FPV groundstation, and accidentally plugged in cables into the switch the wrong way round as they are all blue crimp connectors, but I did it in the garden just to play it safe, and sure enough, the fraction of a second it was switched on and sparked, the lipo and its cables, and the EC5 on the end of it got VERY warm indeed, so I unplugged it and left it outside..

 

It happened in the blink of an eye, the time it takes to flick a switch on and immediately off again..

 

No puffing at all, it just got instantly hot...

 

Am I right in assuming it simply discharged EVERYTHING it had, all at once in that shorting out, hence it being dead, and the heat?

Whats the best way to dispose of it, as I wouldnt even consider trying to recover it for the sake of £10..?

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Surprised its completely dead, maybe one of the wires is broken or disconnected? Still I would chuck it anyway

 

Sent from my MB525 using Tapatalk 2

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If I remember correctly, I believe you're supposed to soak dead LiPos in salty water for 24 hours to make them inert before disposing of them. I'm sure google will tell tell you for sure.

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Thanks guys... I've give overlander a call tomorrow and ask them :-)

For the sake of £10, its not worth prodding about with it and find 1 or 2 cells are live and go bang on me..

 

Needless to say, once I got the wiring the right way round, my groundstation power system is now working, and each battery is switchable, with a pretty green light and a voltmeter to monitor it :D

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If I remember correctly, I believe you're supposed to soak dead LiPos in salty water for 24 hours to make them inert before disposing of them. I'm sure google will tell tell you for sure.

 

That is after you rupture it with a pin or nail.

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If I remember correctly, I believe you're supposed to soak dead LiPos in salty water for 24 hours to make them inert before disposing of them. I'm sure google will tell tell you for sure.

 

That is after you rupture it with a pin or nail.

lol, if you rupture the pack, salt water is the least of your worries :lol:

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Well I was wrong, you don't rupture pack and salt water does nothing apart from slowly corroding the alu tabs, it does not discharge it.

 

Good job I do mine the mans way, fully charge it put the +&- together a chuck it whilst saying "FIRE IN THE HOLE" and watch it slowly ballon until it ruptures and then it lets loose with the fire works, this method won't work on half charged packs the must be fully charge as it need quite a bit of energy for them to pop themselves.

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I'd suggest ThunderPower should know, and they say:-

 

http://thunderpowerrc.com/PDF/DISPOSAL- ... TERIES.pdf

 

This concurs with other advice I have read elsewhere.

 

Its IMO very unlikely the pack is fully dead, just that its serial connections have severed somewhere.

 

I have had three cell LiPo packs turn into two cell measured at the main output, i.e. one cell has shorted. This has been sudden and with no visible symptoms.

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Hmm, thanks Dave... How exactly do I discharge a lipo that has zero voltage at any of its power connectors, both the main cable and the balance leads?

 

I'm not keen on trying to dismantle the thing, and it is likely that it is still juiced up, but has a busted connection somewhere after the short-out..

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Well, the idea behind the salt water bath is twofold, it's in water, always helpful in case it tries to ignite, and it's in a slightly conductive medium which acts as if a resistor has been gently and safely placed across ALL the output terminals and any electrical contact point, external or internal where the water will penetrate.

 

What I usually do is to run the battery down as far as I can (without being too anal over it), then, outdoors, I cut off the leads, power and balance, one at a time carefully avoiding short circuits of course, then I put an old washing bowl of salty water in a corner of the garden out the way and lob it in. Usually you can see the gassing at the terminals starting within a minute or so after the initial trapped air escapes as the battery starts discharging. A couple of weeks later, no bubbles, so I throw into normal refuse.

 

When I started doing this FIVE YEARS back I did check battery voltages before, during and after, as before I lobbed it in I cut open the PCB end of the battery so I could meter prod the cell terminals...............it had ALWAYS flattened the cells, so now I don't bother.

 

Again way back, I tested two cell packs as above EXCEPT I didn't attempt to discharge them at all, they went into the salt water as near fully charged, no drama, a bit more gassing evident at the terminals as you would expect, and two weeks later they were flatter than a flat thing.

 

SO, if your cell set has charge "trapped" in some cells, as I suspect, the salt water bath should from this experience eliminate that.

 

Your call!

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