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Salvaging a lipo pack. Removing the bad cell


#1

I’ve got a 3s pack that has 3.6,3.6, and 3.0. It was damaged because it was just velcroed to the bottom of the board and got banged and almost cut through the foil.

Any of u removed bad cells before? I’m tempted to run it as is and just keep all the cells in the pack under 4 VoLTE and hurry up with my li-ion pack in the meantime. I’m sure someone will tell emthwts a bad idea.


#2

Someone here has, I just can’t remember who.

Edit: Oh, here’s the thread


#3

Hummina, please categorise your posts. It helps to keep everything sorted out and easy to find.


#4

The categories are all possible though. I didn’t know what to pick


#5

Well, it’s related to lipos and they are batteries so it could go under electronics. That’s alright though.


#6

Yes I have swapped out many bad lipo cells and revived dead cells. As long as they don’t read 0 volts.

Do you have replacement cells?


#7

norhing the same mah. Maybe I can just cut it out without soldering(it’s on the end) and ride 11s?


#8

Oh yea if you don’t have a replacement you can just cut out the cell from the tabs. But if you take the cell out then there will be a gap in connection so you’ll have to just run a wire from the previous cell to the following cell. Negative to positive accordingly
You’ll also need a new 11s balance lead and hammwire that up which is easy I’m sure you know how to do it


#9

@Hummie I’ll raise my hand here and say what you already know, that is a terrible idea! Remove it or replace it, but don’t just leave a damaged lipo in use. Were it me, I’d replace the entire pack; if the trauma to the cell was significant enough it might have damaged the other cells in less apparent ways. I’d consider it a serious fire hazard.


#10

I ran it just a couple more times to see. It would end up .5 lower voltage than the others but I’d stop before it got below 3 volts. But then it got warm and won’t show any voltsge…and I’ll cut it out. Had to see what would happen


#11

Stumpy the rare 11s board

Too bad the 3s balance lead won’t fit in the 2s port. Maybe I’ll exacto knife it

Thanks barajabali. I woundnt have tried otherwise.

U can see another hole on another corner of another pack! Stickers aren’t enough! Gota get my 18650 done pronto


#12

that will work. I do it all the time.
for some reason I always have the wrong size JST connector and I’m constantly doing a cut and shut.


EU/Belgian eBoard | 149kV | 12S LiPo -- Checklist & Buildlog
#13

Donate to Radioshack for Recycling :slight_smile:


#14

I’m still laughing thinking about that idea dexter. Dark humor.
I’m thinking of planting the cell in the yard. I’d read that putting a dead cell in water is a good way to discharge it and then u can put it I the trash…and then I found when doing this the tabs just get coated in some oxidation in the water and they insulate and it still has juice.

What should I do to save the neighbor cell that’s at 3.46 while its brother is 4.05? Simply balance or is it screwed forever from the trauma?