RE: Over rated batteries?
OK, here are the results of the tests:
Five cell NIMH AA size battery rated at 2560 MAH comparison:
First test: using 5 volt cutoff and 1000 MAH discharge rate, results = 1932 MAH which translates to 75.4% of the rated value.
Second test: using 4.5 volt cutoff and 500 MAH discharge rate, results = 2006 MAH which translates to 78.4% of the rated value.
I used the same charger and charging method for both tests. I talked to the charger mfg. who gave me additional information on how to charge batteries with their charger to get the maximum capacity. I also used the same precision instrument for discharging the batteries. The test equipment mfg guarantees his equipment is accurate to 1% or less.
As you can see, lowering the cutoff voltage and discharge rates only slightly improved the test results.
I now have used seven different chargers and three different test instruments on six different NIMH batteries from two different distributors. I have been testing batteries for over a month and all of these tests fell far short of the distributors rated value. I can only conclude that at least some of these battery mfg/distributors are over rating their products. Test yours and see.
Best wishes, good luck and good flying.
Heli-NuBee (Roger)