ROBBE PROFI Notice D'utilisation page 28

Self-discharging
LiPoly cells have an extremely low self-charging rate (approx.
0.2% per day) and can therefore be stored over long periods
of time without any problems.
Storage
However, before long periods of storage they should be
charge to about 50-80 %. They should be recharged again
after approx. 4-6 months.
Service life
With low discharge currents, the theoretical service life of a cell
is about 500 charge/discharge cycles. With higher discharge
currents of approx. 3-5 C, the service life is lower at only
approx. 300 cycles. With even higher discharge currents the
cycle number is reduced even more noticeably.
After this the battery is used up and must be disposed of in an
appropriate manner.
Different capacity
If several cells are processed into a battery pack and dischar-
ged with a higher current, then the cells will heat to differing
temperatures as the inner cell cannot release heat easily.
This changes the internal resistance and the release capacity
is lower. This cell is then discharged earlier and there is a risk
that this cell is discharged with a charge end voltage of 2.5
volt.
Strong capacity differences occur in particular with very low
external temperatures. For example, if LiPoly batteries are
flown in an electro-helicopter, then the front cell is cooled gre-
atly by the drive wind while the internal cells are considerably
warmer. As a result of this, the cold cell has a lower capacity
and there is a risk that the colder cell is discharged under the
charge end voltage.
For this reason, we recommend you discharge the LiPoly cells
only to about a 3 volt discharge end voltage to avoid any per-
manent damage to the cells.
Memory effect, cell capacity
Since LiPoly cells have no memory or lazy battery effect, the
discharge-charge (cycles, matches) necessary for NC and
NiMH batteries is not necessary here.
Discharging before charging is also avoided.
Since the capacity of the LiPoly battery is slightly reduced
with each charging, this would cause the cell to lose capa-
city unnecessarily.
Interconnecting battery packs
Interconnection of LiPoly cells in a row or parallel, to increase
voltage or capacity is problematic because of the charge vol-
tage and capacity differences.
Only selected cells can be interconnected into a battery
pack.
Discharge end voltage
Cells with nominal voltage 3.6 V = 2.4 volt
Cells with nominal voltage 3.7 V = 2.5 volt
This is automatically determined by the Profi Homecharger
by setting the battery type and the cell count.
Profi-Home-Charger
28
Important note:
If the charge or discharge end voltages are exceeded or fall
short, the cells will be damaged in the form of permanent
capacity loss. If the boundary value is exceeded the cell is
destroyed, can explode or start to burn.
Safety notes for lithium-ion polymer batteries
This charge device operating manual can only give a general
overview of charging and handling of rechargeable LiPoly bat-
teries; individual instructions from the corresponding battery
manufacturer cannot be replaced by this.
For this reason, you must also observe the notes provided
by the battery manufacturer.
- You must place the battery on an inflammable sur-
face when charging or discharging, and do not leave unatten-
ded.
- Do not submerge the battery in water or any other liquid as
the control module can be damaged in this way and the
battery will be charged with abnormal currents or voltage.
- Do not heat the battery, throw it into fire or place in a micro-
wave.
- Do not charge it when it is short-circuited or if the poles are
reversed
- Do not subject the battery to any pressure, deform or throw
it
- Do not solder directly on the battery
- Do not alter or open the battery
- Do not charge batteries over 4.1 or 4.2 volt per cell
- Do not discharge batteries below 2.4 or 2.5 volt per cell
- Only charge batteries with charge devices suitable for them,
never connect directly to a power supply unit
- Never charge or discharge the battery in open sunlight of in
proximity to heating or fire as the control module can be
damaged in this way
- Do not use the battery in places which are subject to high
static discharge.
- All this can lead to the battery being damage by explo-
ding or catching fire.
- Keep the battery out of the reach of children.
- Do not allow contact between secreted electrolyte and fire;
it is easily combustible and can ignite.
- The electrolyte fluid should not come into contact with
eyes; if it does, rinse immediately with lots of water. Then
find a doctor.
- The electrolyte fluid can also be rinsed off or out of clothes
and other objects with plenty of water.
Order No.
8194