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Lipo Testing Procedures
The only way to really tell the TRUE capacity, "C" ratings of a lipo battery is to test it.
To test capacity, simply charge the battery and discharge over a 1 or 2 "C" amp discharge rate
To test "C" rating, one must discharge the battery under a given load until the voltage begins to drop to 3volts per cell.
Defintions:
"C Rating"A standard measurement often used to determine the safe maximum discharge, expressed in amps. To find "1C", divide the (mah)MiliAmpHours of your battery by 1000. In this example, A 1C battery of 1000mah would be 1amp. If this same battery were a "15C" battery, its maximum discharge would be 15 * 1C or 15*1 amp = 15amps.
To actaully find tbe "C" discharge rate of a given battery, we need to
Charge the battery
Discharge at a known rate, such as 15C for the given battery
Chart Amps, volts, watts, temperature of the pack.
We are looking for a maximum discharge rate that allows the pack to stay cool (Under 120 degrees) and allows a
nearly constant amp discharge over the life of the test. The test ends if the pack overheats, can't hold the amps, or the voltage drops below 3volts per cell. (9v for a 3s1pxxx pack for example)
This is a picture of a lipo testing setup.
It consists of:
Battery
Load (Automotive Carbon pile battery tester)
Eagle Tree data aquisition tool
Temperature probe taped to battery.
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