Is my LiPo pack bad?

[sgtbham]

This is a brand new pack, I was running 2s and I decided to step up to 3s - bought a pack and hooked it up to the charger (dynamite passport ultralite), put it on 3s, and all it says is "cell error - voltage invalid". This is a brand new pack, straight out of the box and onto the charger. What am I doing wrong? Ive charged 2s fine and I charged a 3s pack for my buddy once.... I searched and im still stumped.

[wings_of_fire]

What brand battery is it?

1] The cell error can come because the chargers are usually programmed to work between a set lower and higher limit of voltage. If the cell voltage does not lie between the voltage limits then probably you get that error.
2] Another issue can be a mismatch between the positive and negative terminal of the battery pack and charger port. Check you battery connector leads if they match with the charger port.
3] Lithium based batteries loose their efficiency with time. In case the battery had not sold for a long time and was lying with the retailer, then there are chances that it exhausted pretty much of its life.
4] Manufacturing error.

Try connecting the battery to a different charger, it might work.

[Constant Threat]

Also sometimes the balance plug can have a bad connection. Wiggle the wires around to make sure the pins are making good connection. If your charger has a screen that shows each cells voltage look at that and make sure all cells are reading.

[sgtbham]

I put it on Nimh for about 40 seconds and now its charging on the 3s balance setting....I wonder how screwed this pack is now.

[jaloos]

Originally Posted by sgtbham

I put it on Nimh for about 40 seconds and now its charging on the 3s balance setting....I wonder how screwed this pack is now.

One cell had probably dropped below the wanted voltage. I have had this and charged at 50ma on NiMh mode till the voltage was at the acceptable level. It didn't seem to hurt the pack any.

I do however recommend doing the charging in NiMh mode outside away from combustibles in the even something does go wrong.

[wings_of_fire]

You had your charger set on Nimh and that is why it gave you an error. The charger was seeking a cell voltage of 1.2 volt to 1.5 volt and your lithium battery must have given it a reading of over 3 volt per cell.
Don't worry, the charger never charged the battery in Nimh mode. Your battery is totally fine.

PS :- You are using a Lithium based battery right?

[jaloos]

Originally Posted by wings_of_fire

You had your charger set on Nimh and that is why it gave you an error. The charger was seeking a cell voltage of 1.2 volt to 1.5 volt and your lithium battery must have given it a reading of over 3 volt per cell.
Don't worry, the charger never charged the battery in Nimh mode. Your battery is totally fine.

PS :- You are using a Lithium based battery right?

Pretty sure he was smart enough to try and charge the pack in LiPo mode to begin with and then bumped charged it in NiMh mode after that.

[WHITE-TRASH]

Originally Posted by sgtbham

I put it on Nimh for about 40 seconds and now its charging on the 3s balance setting....I wonder how screwed this pack is now.

It'll be fine. The pack didn't have enough voltage left in it due to age etc and you bumped up the surface voltage so the charger would recognize it. I've had older packs do the same thing. A few seconds on nimh/nicd and they took off and have been just fine since.

[SmokeScx10]

yea like white trash said you should be fine... just make sure you balance charge i dont recommended charging lipos without it...

[sgtbham]

Thanks a lot for the help guys, it was reading 6.7 initially and Im guessing the threshold for 3s is 9v? At any rate it didnt take too long to bump it up to the min and seems to be balance charging fine....so time to find out what 3s breaks in my rig? haha

[jaloos]

Originally Posted by sgtbham

Thanks a lot for the help guys, it was reading 6.7 initially and Im guessing the threshold for 3s is 9v? At any rate it didnt take too long to bump it up to the min and seems to be balance charging fine....so time to find out what 3s breaks in my rig? haha

I would stick to 9.6 volts (3.2v per cell) for the 3s packs.

[JokersWild]

Originally Posted by SmokeScx10

yea like white trash said you should be fine... just make sure you balance charge i dont recommended charging lipos without it...

Balancing isn't required every charge.... Batteries that have sat loose balance.... Batteries that have had full drain become out of balance. A rule of thumb is 1 balance every 5 charges.

As for being in safe...... It's really only un safe if the person never balances and somehow a cell has enough to start charge but will not accept a charge resulting in over volting the other cells/ cell.

Racers see more cycles than anyone...... Known many that never balance ever.