GRAUPNER ULTRA TRIO PLUS 16 Instructions D'utilisation page 41

13. Lithium programs (Output 1)
These programs are only suitable for charging and discharging LiFePO batteries with a voltage of 3.3 V
4
/ Cell, Lithium-Ion batteries with a voltage of 3.6 V / cell, and Lithium-Polymer and Lithium-Manganese
batteries with a voltage of 3.7 V / cell. The outstanding feature of Lithium batteries is their much higher
capacity compared to other battery types. However, this important advantage is offset by the need
to adopt different handling strategies: they must be charged and discharged using specifi c methods,
otherwise they will be damaged, and can be dangerous. The directions in these instructions must be
observed at all times when handling these batteries. Specifi c information and safety notes will also be
found in the battery manufacturer's technical information.
The fundamental rule is that Lithium-based batteries may ONLY be charged using spe-
voltage
cial chargers, and the charge program must be set up correctly in terms of fi nal charge
voltage and capacity for the battery type in use. The charge process is fundamentally
current
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
charge time
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).
Because some types can be charged with upt to 2C or 4C charging current, the charging current and the
capacity of the battery must be set seperately. When the battery on charge reaches the specifi c fi nal voltage
which is appropriate to the battery type, the charger automatically reduces the charge current in order to prevent
the battery exceeding the fi nal 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 balancer connector, 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
LiFePO
even exploding. If the fi nal charge voltage of 3.6 V / cell ( ), 4.1 V / cell (Lithium-Ion) or 4.2 V / cell
4
(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 fi nal 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 and burn! Never connect a
Lithium-based battery to the charger if it features an integral charge circuit! Always place your Lithium
batteries on a non-fl ammable surface for charging.
Lithium
Lithium Lithium
MODE MODE
Lithium
MODE MODE
type
MANUAL- discharge
storage
select
program program
program
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