ORIGINAL: Ross Kean
ORIGINAL: Heli-NuBee
I am using 1000 MAH discharge rate and a cutoff voltage of one volt per cell which is the equipment mfg's recommendation.
You are discharging at too high a rate (C/2) to compare to the manufacturer's ratings. To check the ultimate capacity, you should probably discharge at a c/5 or c/10 rate to around 0.9V. If you are trying to determine the practical capacity, you need to discharge at the same rate you will be using the cell and to the lower voltage limit you will use the cell. Especially for lower quality AA's, the discharge rate can have a significant effect on the measured capacity.
Ross
The difference in capacity between C/2 and C/5 is quite small, while the difference between 1.15 (where many dis chargers cut off) is somewhat larger. The C/2 vs. C/5 difference is smaller than the variation in capacity one would see from lot to lot production of the same design.
Those that expect to get rated capacity at 20C also expect to get the published mileage on their SUVs when pulling a boat at 75 mph.