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Rhondas
12-10-2005, 03:25 AM
what is the peak voltage when fully charged on a 7 cell pack an 8 cell pack and a 6 cell pack ,both Nicads and nimh

Twmaster
12-10-2005, 03:35 AM
It will vary. There are no 'standard' numbers. They will almost always be higher than the cell's rated voltage. For example an 8 cell 9.6V pack may measure over 10 volts after a charge.

savydad
12-10-2005, 05:47 AM
closer to 12v for an 8 cell "peaked" and after resting a few minutes more around 11.5v . Most nickel cells rated at 1.2v will peak @1.45-1.55v depending on type of cell and how good they are. Off the charger voltages will vary, but most are in this range. So, baseline, 6 cell is 8.4-9v, 7 cell is 9.8v-10.5v, and 8 cell is 11-12v. If the rated voltage is all you can get with a fully charged pack i.e. 7.2v on 6 cells, the pack is either gone or you have a bad cell in the pack.

Todd

BillB
12-10-2005, 08:56 AM
Yep, 1.45 (or a bit more) volts per cell is a good figure.

Matt Kirsch
12-10-2005, 09:09 AM
Yep, just don't freak out if it's a bit higher or lower than that.

Rhondas
12-10-2005, 11:15 AM
Yep, just don't freak out if it's a bit higher or lower than that.Thanks ,thats what Im getting with my new 959 brain charger.:cool:

slipstick
12-10-2005, 11:28 AM
But don't think higher voltage is better. The old rule of thumb with NiCds was if the charged voltage gets higher than about 1.6-1.7V/cell the pack will soon be dead. NiMH are similar.

Steve

savydad
12-10-2005, 10:23 PM
Yes, from what I've read, this is the reason that the sensitivity peak detection is different on nimh, they tend to keep climbing and climbing til bam...unless the peak detect circuitry is setup for them. Nicds if allowed to keep charging on a non-peak charger will actually swell up after about 1.7, I know because I've done it in my early days. I was 14 y/o so I didn't know better, but it would have been funny to watch me in those days...found out what happens when you take a knife through both wires on a charged pack quickly. All good lessons learned, just glad I didn't burn anything down or hurt myself in my experiments.

Todd