d) Discharge Current
Normatively, the battery capacity is determined at a discharge current of 0.2 C. For the
example batteries, this means:
1000 mAh x 0.2 = 200 mA
2700 mAh x 0.2 = 540 mA
The discharge current must be chosen that comes closest to the calculated value. For the
1000 mAh battery, these are 250 mA, and for the 2700 mAh batteries, a discharge current
of 500 mA results.
Long-term determination of a battery's capacity leading to the same discharge current
every time can be used to determine its current condition (capacity loss).
The delivered capacity depends strongly on the discharge current: The lower the
discharge current the higher the capacity that can be delivered.
Since the rechargeable battery is discharged via resistors, the actual discharge
current depends on the current battery voltage. Of course, this is considered in the
capacity calculation (DCAP) of the "Charge Manager 420".
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