volts per cell difference

[crustysphinkter]

Hi I've just got my eighth turnigy 6 cell 5000mah pack. When charging, cell 6 gets up to 4.15 volts then thats it. the other 5 all ballance out around 4.2. None of my other 7 packs are like this, some of them are in to 50-60 cycles. I do parallel charge my packs with an icharger 306b but when new i usually charge them on there own for 5 cycles or so. is there a problem with this pack? shall i put a few more cycles in to it or do I need to send it back? the IR is 1 on all cells

[BenScoobert]

how far out is it after discharge?

[crustysphinkter]

It s only had one cycle and all cells came out around 3.8v
So i put the pack on with 3 others, discharged them to 3.9v per cell, then charged them again. Checked the pack it was spot on. Discharged the one pack to 3.9v per cell again then charged it on its own, all 6 cells 4.2v :-)
Sent from my GT-I9100 using Tapatalk 2

[cjcj1949]

There are a lot of balance options on the icharger. You may have selected one that didn't keep charging until all cell were balanced. This assumes that cell 6 was low when you started. Parallel charging is brute force balancing with no current limit, so you may have gone from one extreme to the other. Now that it is balanced your normal balanced charge can manage to keep it balanced. It is strange though that cell 6 ended up the same voltage as all the others at 3.8V. To find out what is going on you need to measure things more accurately and measure cells when you get them and before you charge them. The ir values on the icharger are not as accurate as they need to be to sort out what is going on. On the other hand, even if you had all the information, it wouldn't help that much as we don't know why cell 6 was low when delivered. It may be a fault with the original charger or the cell may be losing charge quickly or may have been stored for a long time. Hopefully the cell never had a problem, but it would be worth keeping a check on it. You could mention the problem to HobbyKing and ask for their advice. You could say that you don't want to accept it as it wasn't fit for purpose when delivered and it looks as though it has a fault that is draining charge. If it has a fault, it will only get worse. I think you can return items to the German warehouse now.