4
2.2 Battery charger
Adaptive 4-stage charging characteristics: bulk – absorption – float – storage
The microprocessor-driven adaptive battery management system can be adjusted for various
types of batteries. The adaptive function automatically adapts the charging process to battery
use.
The right amount of charge: variable absorption time
In the event of slight battery discharge, absorption is kept short to prevent overcharging and
excessive gas formation. After deep discharging, the absorption time is automatically
extended in order to fully charge the battery.
Preventing damage due to excessive gassing: the BatterySafe mode
If, in order to quickly charge a battery, a high charge current in combination with a high
absorption voltage has been chosen, damage due to excessive gassing will be prevented by
automatically limiting the rate of voltage increase once the gassing voltage has been
reached.
Less maintenance and aging when the battery is not in use: the Storage mode
The Storage mode kicks in whenever the battery has not been subjected to discharge during
24 hours. In the Storage mode float voltage is reduced to 2,2V/cell (13,2V for 12V battery) to
minimise gassing and corrosion of the positive plates. Once a week the voltage is raised
back to the absorption level to ‘equalize’ the battery. This feature prevents stratification of the
electrolyte and sulphation, a major cause of early battery failure.
Two DC outputs for charging two batteries
The main DC terminal can supply the full output current. The second output, intended for
charging a starter battery, is limited to 4A and has a slightly lower output voltage.
Increasing service life of the battery: temperature compensation
The temperature sensor (supplied with the product) serves to reduce charging voltage when
battery temperature rises. This is particularly important for maintenance-free batteries, which
could otherwise dry out by overcharging.
More on batteries and charging
Our book ‘Energy Unlimited’ offers further information on batteries and battery charging, and
is available free of charge on our website (see www.victronenergy.com -> Support &
Downloads’ -> General Technical Information). For more information on adaptive charging,
please also refer to the General Technical Information our website.
