After draining with Battery Amnesia, I was watching EMMpathy while charging the battery. We might possibly not be getting to full charge --OR-- we may not be using all of the capacity before the PB thinks the power is too low.
As charging begins, Measured Total Capacity remains at 1752mAH. The remaining capacity starts building up from 0 (basically how much mAH the software feels has been pushed back into the pack) and the % of charged increases accordingly. I noticed the Current Temperature also starts rising.
At around 79% I noticed the Current Temperature is sitting around 54C and rising. This is above what EMMpathy shows as the Max Charge Temperature which is 50C. The % keeps toggling between 79%, 79.5%, 80% as the temperature continues rising all the way to 58C. At this point the Remaining Capacity has gotten up to 1400mAH (which again is what the charging has put back into the pack -- not necessarily how much the pack has -- although if Battery Amnesia drained the battery, the capacity in the pack should be fairly low). Then as the temperature hits 59C, the pack shows Calibrate as the Charge State... and then shortly after the Remaining Capacity jumps to 1752mAH, the Measured Capacity is still 1752mAH, and it stops charging. The Charge State then keeps flipping between Maint Charge (maintenance/trickle charge) and Wait EMM. Right now, it's still doing this and the temperature has gotten up to 60.5C and stopped there.
I'm curious if it's stopping the charge due to the temperature? This is a 2100mAH pack. It's put in 1400mAH.
Most of the determination on pack charge I believe is done via the voltage. I did read somewhere (mentioned this on my PB160 battery thread) that outside of capacity differences between A, AA, and AAA, there's another difference which is the potential for voltage drop during load. This is why I was trying to remember if the stock cells were A size cells or AA. I think they may have been A. If the voltage is less consistent on load with the AAs than the As, I'm curious if it's possible that my pack has about 1/3rd of a charge remaining (+/- a few hundred mAH) but due to voltage fluctuations, it's treated as empty?
The temperature is finally coming down ... now at 59.5C as I'm writing this (and the charge state is still flipping between the maintenance charge and waiting for emm states).
I also read somewhere that trickle charging (ie. maintenance charge?) aren't good with modern NiMH packs after they are fully charged. I think they said any cell with a listed capacity over 2000mAH doesn't have enough headroom to properly handle trickle charging or top off charging continuously after a full charge?
EDIT: additional thing that's interesting. On a full pack, when I fire up Battery Amnesia, it reports that there's only 47-50% left to drain. Even on a full pack. Hmm.
EDIT2: Battery Amnesia is supposed to almost fully discharge a battery by disabling all the system warnings and continuing to put load on the battery to drain it as fast as it can. The last packed I drained was at around 90% charge (based on what System 7 is telling me) and it took 74 minutes for Battery Amnesia to drain it.
