Alpha Technologies Lomain Ni-Cd Pocket Plate Battery - Manual (Page 24)

745-680-B10-001 Rev. A 24
6.0 Charging
The Lomain Ni-Cd battery can generally be charged by all normal methods. Usually, batteries in
parallel operation with charger and load are charged with constant voltage. For operations where the
battery is charged separately from the load, charging with constant current is possible. Overcharging
will not damage the battery but will lead to an increase of water consumption.
6.1 Constant voltage charge
The common method to charge a battery in stationary applications is carried out by a
constant voltage system and the recommended solution is to use a two-rate type that is
able to provide a constant voltage charge and a lower floating voltage or single rate floating
voltage. The two level charger has an high voltage stage to charge the battery properly after
a discharge followed by a lower voltage float level charge. This results in a quick charge of
the battery and in relatively low water consumption due to the low level float charge.
Two level charge
Boost charge: 1.45 Floating 1.40 – 1.42 V/cell
A high voltage will increase the speed and efficiency of recharging the battery.
In reality often single level charger can be found. This is surely a compromise
between a voltage high enough to charge the battery and low enough to have
adequate water consumption.
Single level charge
1.43 – 1.45 V/cell
For commisioning the batteries, please see Section 7.0, “Commissioning”.