I have been testing Powerex 2700 mAH AA and Powerex 1000mAH AAA cells all week. Decided to do a forming charge at 200mA on the 2700's and a 80mA forming charge on the 1000's. First, what I used to test them.
Cadex 7400ER battery analyzer
LaCrosse BC900 battery analyzer
Maha MH-C401FS charger (AAA)
ZTS battery tester
Fluke 179 True RMS multi-meter
First the Powerex 2700mAH AA NiMH cells
Forming charge of 200mA was performed by the LaCrosse BC900 battery analyzer Version 32
Cadex 7400ER battery analyzer
0.2C charge and 0.2C discharge rate (540mA) Two cycles
0.92V voltage cut-off
97 to 99% on twelve batteries (2619mAH to 2673mAH)
Loaded 8 of them in series for a 9.6V 2700mAH pack with 0.2C charge/discharge and 1.0V cut-off two cycles
Tested at 1 amp charge 1.75 amp discharge 1.0V cut-off two cycles (four batteries tested)
93 to 94% (2511mAH to 2538mAH)
The reason for the odd 1.75 amp discharge rate is to see how they would perform when loaded down with my MillerMods U bin L1P helmet light. An hour twenty minutes of runtime rocks!
Testing with BC900 battery analyzer 1000mA charge and 500mA discharge 0.9V cut-off
2.81 to 2.91 Ah with all twelve batteries tested.
Powerex 1000mAH AAA cell testing (four cells)
Two cells formed on Cadex at 80mA charge and two cells formed at 200mA on a Maha MH 401FS
0.2C charge/discharge rate (200mA) two cycles
97 to 99% (970 to 990mAH)
0.5C charge (500mA) 1.3C discharge (1.3 amps) 0.92V cut-off two cycles
91 to 93% (910 to 930mAH)
Oddball rate due to testing for a Peak Baltic Super Ultra Power AAA Luxeon flashlight to determine runtime.
0.5C charge (500mA) 1.0C discharge (1 amp) 1.0V discharge rate two batteries in series (2.4V) Two batteries that gave equal 92% rate at 1.3 amp discharge were chosen since they were balanced.
Reason for testing in a series pair is to check estimated runtime for a Peak Baltic Super Ultra Power 2xAAA Luxeon flashlight.
Overall, the Powerex 2700mAH AA cells have the highest capacity I've ever seen. Very impressive that they hold up under the 1.75 amp discharge testing and do fine with 8 of them in series (upcoming Quad XR-E Mag) The BC900 testing was done after the 8 in series testing to see how far out of balance they became (2.84 to 2.91 Ah with the 8 cells)
What really, really impressed me was the Powerex 1000mAH AAA cells. My guessimate was 750mAH at 1.3 amp discharge but they grunted out at least 910mAH. Having them hold 940mAH at a 1C discharge with two in series was icing on the cake.
Since I only had two Cadex channels available at the time, I went with testing how well the Maha MH 401FS forms them at C/5. The Maha formed batteries actually outperformed the Cadex formed batteries at C/13 The sample size was way to small but the rest of the guys at work saw my results and went with the Maha.
There you go... my first major battery testing. Can't hold a candle to SilverFox but I figured somebody might find my results interesting.
EDIT: The Powerex 1000's were discharged at 1.3 amps (C1.3) and not 1.25 amps. Was recharging one of the cells and noticed the battery label stated 1.3 amps.
ADDED 21 October
One of the guys at work took two of his Powerex 1000mA AAA batteries and connected them to the Cadex to try something different. He ran them at a 80mA charge/condition/200mA discharge rate for two cycles and after 56 hours (and still recharging) his results were 98% and 100% on one battery and 99% and 97% on the second battery.
This is the long slow charge with termination at 1.53V the Cadex performs. I am not aware it will allow you to dumb charge the battery as I have check the many functions it performs in the last few months.
Checked two of my AAA batteries in the BC-900 that were rated 97 and 99% on the Cadex. They returned 983mAH and 1039mAH with a 200mA charge (C/5) and 100mA discharge (C/10) rates. Although the BC-900 reads slightly high, it does point out which battery is the strongest so I can keep an eye on battery balance across packs.
My co-workers results with four 1000mA Powerex cells on the Cadex 7400ER 80mA charge/recondition/200mA discharge are 97%, 99%, 99% and 100% so after 8 batteries tested, they all read 97 to 100% with about a 99% average across 8 cells.