ROBBE POWER PEAK MAXAMP 8121, Руководство по эксплуатации

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Order No.
8121
Supplementary Instructions
POWER PEAK MAXAMP LI
Final charge voltage:
Cells of 3.6 V nominal voltage = 4.1 Volt
Cells of 3.7 V nominal voltage = 4.2 Volt
Final discharge voltage:
Cells of 3.6 V nominal voltage = 2.4 Volt
Cells of 3.7 V nominal voltage = 2.5 Volt
Important note:
If the stated limits for final charge or disch-
arge voltage are exceeded, the cell will be
damaged; the damage takes the form of
permanent capacity loss. If the limit values
are exceeded for a protracted period, the
cell will be ruined, and may explode and
start a fire.
Effective cell 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 relati-
vely 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 tempe-
rature index which means that the full nomi-
nal capacity is not available at very low and
very high temperatures.
9
The external cell temperature should not
exceed certain limits during charging (45°C)
and discharging (60°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.
Variations in capacity
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
unable to dissipate heat effectively.
This results in changes to the cells’ internal
resistance, which in turn reduces their
discharge capacity. The cell concerned will
then be discharged more quickly, with the
danger that it will eventually be discharged
below the permissible final charge 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
warmer. 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.
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.
C
a
p
a
c
it
y
in
%
Temperature °C