How far out of balance can a Lipo get befor I should worry ?

[Bondonutz]

I checked on one of my E-Revos today that I hadn't run in a month or so. I couldn't remember what state the Lipos were in since I used it last, anyway looks like I put it up with fully charged 2s packs (TrueRC 15C -20C burst)
I've had these packs for nearly 2 yrs and have served my very well so if they are on the way out I'm fine w/that.

One pack is even across the board and the other the #1 cell is 0.5 volts lower than #2. It stays this way regardless using the DUO3 to discharge or running them down via driving and when charging it falls 0.4-0.5 short still. The pack is still hard as a brick, no puffiness at all.

I never had a Lipo start to go like this, they usually start to swell or a cell just falls completely. Should I be prepared to chuck it or just run the dam thing till it starts to puff or not worry at all ?

EDIT, Now that I have a DOU3 I plan on doing the "storage" thing, Is 80% still the prefered percentage to doing this ?

[sikeston34m]

Originally Posted by Bondonutz

I checked on one of my E-Revos today that I hadn't run in a month or so. I couldn't remember what state the Lipos were in since I used it last, anyway looks like I put it up with fully charged 2s packs (TrueRC 15C -20C burst)
I've had these packs for nearly 2 yrs and have served my very well so if they are on the way out I'm fine w/that.

One pack is even across the board and the other the #1 cell is 0.5 volts lower than #2. It stays this way regardless using the DUO3 to discharge or running them down via driving and when charging it falls 0.4-0.5 short still. The pack is still hard as a brick, no puffiness at all.

I never had a Lipo start to go like this, they usually start to swell or a cell just falls completely. Should I be prepared to chuck it or just run the dam thing till it starts to puff or not worry at all ?

EDIT, Now that I have a DOU3 I plan on doing the "storage" thing, Is 80% still the prefered percentage to doing this ?

Time for a balance charge. Or even a balancing discharge.

It seems like you should be able to make those cells come back in line with each other.

I would run it till it puffs.

I usually store my lipos at 3.8 volts per cell.

[Bondonutz]

Originally Posted by sikeston34m

Time for a balance charge. Or even a balancing discharge.

It seems like you should be able to make those cells come back in line with each other.

I would run it till it puffs.

I usually store my lipos at 3.8 volts per cell.

I've run it down to LVC and recharged, then balanced discharged and she still 0.5 below #2. Then I started the thread because I didn't know what to think ?
Maybe it'll get better after a few more cycles?

If not, I guess I'll do exactly what you said. Run it till it looks like a MaxAmps packs

[DCastaneda]

I've had a similar experience with a Zippy pack. Storage charge the pack so all cells reach the same voltage, and then raise your cutoff voltage a tad. chances are the individual cells vary in capacity to some extent, and if your LVC is too low, the smaller cells dump out and you end up with a severely unbalanced pack. Let me know if it works

[Bondonutz]

LVC is set at 3.40 and the charger has the same reading on display for the #1 cell when charging cycle starts. Should I consider a higher VC amount even though it's at 3.40 ?

[pinkpanda3310]

Have you thought about charging the cells individually through the balance tap? Maybe do a cycle on each to see if there is a mah difference like mentioned.

[Bondonutz]

PP3310,

Fine suggestion , one I def will consider if this problem persists after a couple more cycles.
Thanks