Functioning
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Before starting to use the rechargeable battery, it is necessary to charge it
completely.
Battery Capacity at the Delivery
The supplied rechargeable battery is delivered in a partially discharged state, as it
takes considerable time from the complete charge at the manufacturer’s plant.
The spontaneous discharge of the rechargeable battery at the room temperature
achieves 5% per month. It means that the battery can half discharge in 9-12 months
after its complete charge.
Life Time of Rechargeable Battery
The life time of battery is defined by the number of complete “charge-discharge”
cycles. In real use conditions the number of cycles varies from 500 to 1000 depending
on the discharge depth, at that the battery capacity decreases to 60-80% from the
nominal value. The number of cycles corresponds to 2-4 years of real operation (in
average, 5-6 “charge-discharge” cycles per week).
The life time of battery is not indicated. Usually the storage life before the operation
start is 2 years.
Important Note Concerning the Correct Use and Charge of Li-Ion Battery
The battery is exposed to wear because of its construction. The life time of the battery
depends also on the correct technical servicing. The charge and the discharge are
the most important wear-out factors.
As far as the Li-ion battery have no “memory effect”, it is allowed to charge/discharge
the battery at any charge level. Though once every several months it is recommended
to discharge the device completely, i.e. wait for the device switching off and then
charge it completely.
Often complete discharge of the battery is not recommended. If the battery is
discharged completely, charge it as soon as possible.
The overcharge is even more harmful for the Li-ion battery than the over-discharge.
The controller limits the maximal charge level but there is one peculiarity. It is well
known that the battery capacity depends on the temperature. Thus, for example, we
charged the battery at the room temperature and obtained 100% charge, the battery
charge level may decrease to 80% and more when going out to the frosty weather and
device cooling down. The reverse situation may also happen. The battery charged
100% at room temperature may warm to 105% what is rather bad for it. Such situations
may occur if the device operates with the connected power supply unit during the long-
term period of time. During the operation the temperature of the device and also
the battery increase and as far as the charge is complete, the over-charge takes place.
That is why if you intend to work with the mains supply, disconnect the device from the
