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8. General Information
For further understanding of the charger function, a few explanations of terms and some infor-
mation is required:
Battery capacity (mAh)
This describes the theoretic energy volume that a fully charged rechargeable battery may emit.
A rechargeable battery with a capacity of 2500 mAh may, e.g., theoretically emit a current of
1000 mA (= 1 A) across 2.5 h (or a flow of 250 mA across 10 h).
Charging/discharging rate (C)
The charging or discharging rate marks a ratio between charging/discharging current and the
battery capacity.
For a rechargeable battery with a capacity of 2500 mAh, a charging/discharging rate of 0.1C
means a charging/discharging current of 250 mA. At a rechargeable battery with 1000 mAh, 0.1C
represents a charging/discharging current of 100 mA.
Usually, the charging rate for a modern NiMH rechargeable battery should be between 0.33C
and 1C.
If the charging rate is too high, the charger may switch off early, which will prevent the
rechargeable battery from being fully loaded. A too-high charging rate also leads to too
much heating up of the rechargeable battery, which may lead to safety deactivation
of the charger.
Therefore, it is recommended for AA/Mignon or AAA/Micro rechargeable batteries to
choose a value of up to about 0.5C for the charging rate and calculate a maximum
charging current from this.
Example: rechargeable battery capacity = 2500 mAh, charging rate 0.5C -> charging
current 1250 mA
Set a charging current of 1200 or 1300 mA at the charger here.
The discharge rate must not be above 1C. In a AAA/Micro rechargeable battery with a capacity
of 700 mAh, the discharging current should not exceed 700 mA.
If too high a discharge rate is chosen, the rechargeable battery is not fully discharged
since the voltage at the rechargeable battery drops too strongly.
Observe that the charger offers a maximum discharge current of 1000 mA (= 1 A).
