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Discharge (C)
Discharge is the amount of power the battery can 'push' out and the number shown '20C' is an multiplication of the capacity. For example; A 20C battery can discharge at 20 x 2,000mAh which is 40,000mAh or 40Amps.
This is an important number if you know your motor requires a certain power level.
In addition to this, batteries have a 'Burst' rate, which is the amount of power the battery can discharge for a short period, usually 10-20 seconds. A typical battery label may show 20-30C, this would mean a 1,000mAh battery can discharge 20,000mAh constantly or give a sudden and short 10-20 second 30,000mAh (30A) burst of power.
Tip: A higher 'C' rated battery will last longer if run at a lower 'C' rate. Example: a 30C battery run at 20C maximum will have a longer cycle life than a 20C run at 20C each flight.
