GRAUPNER 6442 Instructions D'utilisation page 27

The fundamental rule is that Lithium-based batteries may ONLY be charged using
special chargers, and the charge program must be set up correctly in terms of final
charge voltage and capacity for the battery type in use. The charge process is
fundamentally different to that required for Ni-Cd or Ni-MH batteries, and is termed
a constant current / constant voltage method. The charge current required varies
according to the battery capacity, and is set automatically by the charger. Lithium
batteries are usually charged at the 1C rate (1C charge rate = half capacity as charge current. Example:
battery capacity 1500 mAh: 1C charge current = 1500 mA = 1.5 A). For this reason it is essential to set
the charger to the battery capacity instead of the charge current. When the battery on charge reaches
the specific final voltage which is appropriate to the battery type, the charger automatically reduces the
charge current in order to prevent the battery exceeding the final permissible voltage. If the battery
manufacturer states a charge current lower than the 1C rate, then the capacity (charge current) must be
reduced accordingly.
We recommend the use of the LiPo Balancer 6 plus, Order No. 3065, which ensures that your
Lithium batteries are charged optimally, and therefore increases safety and their useful life.
Problems caused by mistreating batteries:
It is very dangerous to overcharge Lithium-Ion batteries, as they tend to react by gassing, overheating
and even exploding. If the final charge voltage of 3.6 V / cell (
V / cell (Lithium-Polymer and Lithium-Manganese) is exceeded by more than 1%, the lithium ions in the
cell start to change into metallic lithium. This material reacts very violently with the water in the electrolyte,
and this can result in the cell exploding. On the other hand it is also important to avoid terminating the
charge process before the final charge voltage is reached, since this reduces the effective capacity of
the Lithium-Ion cell markedly. Stopping the charge at just 0.1 V under the threshold means a capacity
loss of around 7%. Lithium batteries must not be deep-discharged, as this leads to a rapid loss of
capacity. This effect is irreversible; it is absolutely vital to avoid discharging the batteries to below 2.5 V
/ cell.
Caution: the cell type, cell capacity and cell count set on the charger must always be correct for
the battery to be charged; if you make a mistake, the battery could explode! Never connect a
Lithium-based battery to the charger if it features an integral charge circuit! Always place your
Lithium batteries on a non-flammable surface for charging
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
L i P o m a n u a l
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
C : 2 5 0 0 m A h
+
-
INC DEC
The charger automatically sets the charge current of 1C based on this information.
When you connect the pack to the charger and start the charge process, the charge current
starts at 0.00 A and slowly rises to the set limit.However, please do not be surprised if the
charger does not reach the current you have set, because the charge program constantly
monitors the battery voltage in order to prevent the pack inflating, provided that the voltage of
the individual cells in the pack is the same.When the charger automatically reduces the charge
current, the screen displays the message „END", alternating with the reduced charge current.
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
L i P o d i s c h a r g e
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
1 . 0 0 A 2 . 5 V / c e l l
+
-
INC
DEC
ENTER
Lithium manual program
This program charges the battery using the capacity
(charge current) which you set.
Before you initiate the actual program you must set the
capacity of the pack (and thus the maximum charge
current - range 50 ... 10000 mAh) using the INC / DEC
buttons.
Lithium discharge program
The purpose of this program is to determine the residual
capacity of a Lithium pack which has not been fully
discharged.
The program discharges the pack using the set discharge
+
-
current (0.10 ... 5.00 A, left of screen) down to the set final
INC DEC
discharge voltage (2.5 ... 3.7 V per cell, right of screen). It
is not possible to set a final discharge voltage below 2.5 V
per cell, otherwise the battery will suffer permanent
damage.
LiFePO
), 4.1 V / cell (Lithium-Ion) or 4.2
4
voltage
current
charge time
27