Same one bad cell in 2 batteries??

[Cypher]

Hi.

I have 2x Spektrum smart 3s 5000mah 30C (G2) batteries, and both of them seems to drop the first cell down to 3.1v and cell 2 and 3 is around 3.5v when LVC kicks in. Could this be both batteries have the same cell gone bad?

They are fairly new, couple of months old, and have been like this from the start. Haven't thought much about it before now. I'm pretty new to this hobby, that's why I went with the smart batteries and such....

 

[gotnitro]

Coincidence maybe. Do they both charge to 4.2 on all cells?

 

[Cypher]

Coincidence maybe. Do they both charge to 4.2 on all cells?

Yes. Or, I have set them to stop at 4.15v. so they are balanced charged every time, since i have no choice with the G2 smart batteries. Can't "forget" the balance plug on these

 

[RedOctobyr]

I have a few (old) 6S LiPos that appear to have weak cell #1's. They'll be balanced when they finish charging, but you go use them, and cell #1 will be lower than the others.

Same brand, same capacity batteries, bought at the same time. Perhaps totally-random coincidence, or maybe something else? I don't think it's the charger, since I didn't see this with other 6S LiPos. I can't think of why cell #1 would be any different than the rest (nothing additional was connected just to that cell), so presumably it's just random. But still, it's weird.

LiPos (dumb ones, anyways) CAN be disassembled, and bad cells swapped. In theory, anyways. But I've never attempted it. It hasn't been worth it to me, and the risks are significant. Even if you run it down to a low voltage first, to reduce the stored potential energy, it could still do something unpleasant if you shorted a cell.

In your case, since it's been since-new, and since they're only a few months old, AND since Horizon is usually pretty good with warranty coverage, I would reach out and see if they're replace them. That might be more difficult from Norway? But it still seems worth reaching out, anyways.

 

[Cypher]

I have a few (old) 6S LiPos that appear to have weak cell #1's. They'll be balanced when they finish charging, but you go use them, and cell #1 will be lower than the others.

Same brand, same capacity batteries, bought at the same time. Perhaps totally-random coincidence, or maybe something else? I don't think it's the charger, since I didn't see this with other 6S LiPos. I can't think of why cell #1 would be any different than the rest (nothing additional was connected just to that cell), so presumably it's just random. But still, it's weird.

LiPos (dumb ones, anyways) CAN be disassembled, and bad cells swapped. In theory, anyways. But I've never attempted it. It hasn't been worth it to me, and the risks are significant. Even if you run it down to a low voltage first, to reduce the stored potential energy, it could still do something unpleasant if you shorted a cell.

In your case, since it's been since-new, and since they're only a few months old, AND since Horizon is usually pretty good with warranty coverage, I would reach out and see if they're replace them. That might be more difficult from Norway? But it still seems worth reaching out, anyways.

Yeah, I could try to return them to the supplier. Then again, if its something that can happen, maybe I'll just let this one go. I have ok runtime and I don't get fault on the battery history (overcharge or discharge) so I guess it's within limits. Bit I've read that 3.1v is very low end...

 

[hobo]

sounds like there on there way out had a lipo do that to me and it got slowly worse and it would take ages to charge. strange that they have been like that from new though

 

[Cypher]

sounds like there on there way out had a lipo do that to me and it got slowly worse and it would take ages to charge. strange that they have been like that from new though

I've had bad experience with these batteries. One I had to return after a couple of charges, since one cell had "disappeared". When I put it in the charger, it showed 7.4v and only cell #1 and #3.... When charging that battery(when it was "working"), when I looked at balance, it lost connection with all 3 cells for maybe 30sec, said 0.0v on all 3, then they reappeared......