Temperature Range - ROBBE POWER PEAK ULTIMATE 2 Manual De Uso

USEFUL LIFE:
The theoretical useful life of a cell when discharged at a low discharge current is around
500 charge / discharge cycles. However, if the discharge current is relatively high - around
3C - 5C - the cell's useful life is reduced to around 300 cycles. If even higher discharge
currents are used, the cycle life suffers a further significant reduction.

TEMPERATURE RANGE:

Charging: -> 0° ... +45°C
Discharging -> -20° ... +60°C
TEMPERATURE BEHAVIOUR
Lithium cells feature a pronounced temperature index which means that the full nominal
capacity is not available at very low and very high temperatures. The external cell tem-
perature should not exceed certain limits during charging (45°C) and discharging (60°C),
Temperature curve
unable to dissipate heat effectively.
This results in changes to the cells' internal resistance, which in turn reduces their disch-
arge capacity. The cell concerned will then be discharged more quickly, with the danger
that it will eventually be discharged below the permissible final discharge voltage of 2.5
Volts.
Considerable differences in capacity can occur when external temperatures are very low.
For example, if a Li-poly pack is flown in an electric helicopter, the front cell will be coo-
led very effectively by the normal airflow, while the inner cells become significantly war-
mer. The colder cell will lose effective capacity, with the danger that it will be discharged
below the permissible final discharge voltage.
To avoid the danger of permanent cell damage we recommend that Li-poly cells should
only be discharged down to a final discharge voltage of about 3 Volts. It is also essential
to ensure that the cells are charged up to the same level next time the pack is recharged.
STORAGE
Li-poly cells feature an extremely low rate of self-discharge (approx. 0.2% per day), and
can therefore be stored for long periods without problems. However, before a protracted
period of storage they should be charged up to about 50 - 80% capacity. They should be
topped up again after about 4 - 6 months.
Operating instructions
POWER PEAK ULTIMATE 2
Temperature °C
otherwise the cell will be damaged, with a
permanent loss of capacity.
If the limit values are exceeded for a pro-
tracted period, the cell will be ruined, and
may explode and start a fire.
CAPACITY DIFFERENCES
If several cells are assembled to form a bat-
tery which is then discharged at a fairly high
current, the cells will heat up to different
extents as the cell or cells on the inside are
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