Puff of smoke from LIPO battery...

[liamcaff]

Hi guys,

I have a 20s LIPO battery made up of 10 x 4s Turnigy LIPO batteries 5s2p...

I was changing the position of some of the batteries and short circuited 2 of the batteries momentarily... There was a large puff of smoke from one of the LIPO batteries.

Do you think it's safe to still use it?

 

[Alan B]

Depends what the smoke was from. If the wires, they might be repaired. If the cells, probably not going to be safe.

In any case proceed with care and fully test the two batteries for full discharge capacity and inspect/repair all the internal wiring. Or be safe and just replace it.

I had this happen once and it was just the main connectors that failed. The two batteries involved continued to work fine. I replaced the connectors and it was fine.

The battery connectors aren't very safe if they can be plugged together this way. The 4mm dual plugs have this problem. It is easy to make this error when plugging a stack together.

 

[liamcaff]

Depends what the smoke was from. If the wires, they might be repaired. If the cells, probably not going to be safe.

In any case proceed with care and fully test the two batteries for full discharge capacity and inspect/repair all the internal wiring. Or be safe and just replace it.

I had this happen once and it was just the main connectors that failed. The two batteries involved continued to work fine. I replaced the connectors and it was fine.

The battery connectors aren't very safe if they can be plugged together this way. The 4mm dual plugs have this problem. It is easy to make this error when plugging a stack together.

Thanks Alan,

I'll take you advice and have a very close look at the batteries before I try to use them... And probably order some replacements just in case

 

[dogman dan]

If you misconnect at the mains, it will usually melt a tab on a cell, acting a bit like a fuse. That pack with the melted tab won't work now. It usually is possible to move the red wire, and then have a 4s pack where you had a 5s before, or whatever. But the cell with the tab melted off is not usable. You can peel off that cell, but I tend to just use it with the dead cell bypassed but in place.

Roached packs like this, I use to run my 24v lawnmower.

 

[liamcaff]

If you misconnect at the mains, it will usually melt a tab on a cell, acting a bit like a fuse. That pack with the melted tab won't work now. It usually is possible to move the red wire, and then have a 4s pack where you had a 5s before, or whatever. But the cell with the tab melted off is not usable. You can peel off that cell, but I tend to just use it with the dead cell bypassed but in place.

Roached packs like this, I use to run my 24v lawnmower.

Thanks for the tip dogman! I have some old 4s packs with good cells so I might try to replace the dead one

 

[dogman dan]

Or just stack on a new cell, bypassing the cell with no tab with a thick wire.

Peeling those things apart can damage the good cell, so I just leave it there in place. Discharge that cell if there is enough tab left to get a contact temporarily.

Still the risk of damaging the old 4s cells unsticking them, but in that case you have three chances to try it without damage to the cell.