What factors should I consider
when choosing a battery
How many battery banks will you be
charging? Take into account service
battery, starter, bowthruster, etc. Also
consider any possible future extension
of your system
(= sufficient battery
The battery charger must have the
same voltage as the battery, i.e. 12 V
battery voltage = 12 V battery charger.
And 24 V battery voltage requires a
24 V battery charger.
Charging the batteries safely and
quickly requires sufficient charge
(measured in amps). See the
battery charger specifications in this
Powerbook for the recommended
For the simple and often cheaper battery
chargers, the charge current is specified
for the nominal battery voltage (= 12
or 24 V). Charging a battery requires a
higher charge voltage, namely 14.4 or
28.8 V. If the charge current drops at this
(higher) charge voltage, it will take much
longer for the battery to be charged. This
results in a shorter lifespan of the battery
or a longer generator time (if the battery
charger is powered by a generator).
Battery chargers from Mastervolt
provide a full charge current, even at
a high charge voltage and high
ambient temperatures. This ensures
short charging times and an optimal
lifespan for your batteries.
What type of battery can I charge?
Mastervolt battery chargers are suitable
for all types of batteries. Full details can
be found in the battery charger specifi
cations under ‘Charge characteristic’.
Mastervolt recommends choosing a
battery charger with sufficient capacity
and, if possible, connecting it to a battery
temperature sensor and battery voltage
sense. Always connect Lithium Ion bat-
teries in accordance with the supplied
instructions and follow the installation
guidelines carefully (temperature com-
pensated charge is not needed).
Can I charge different types
of Lithium Ion batteries?
Most Mastervolt battery chargers can
charge Lithium Ion batteries. When
using the modern Mastervolt Lithium
Ion batteries (MLI and MLS series), free
downloadable configuration software
(MasterAdjust) allows you to simply
adjust the battery charger. Other charge
characteristics can also be easily installed.
Do note that all Lithium Ion batteries
should be installed in accordance with
the manufacturer’s instructions.
Can a Mastervolt battery
charger remain connected
throughout the winter?
Yes, that’s not a problem. Mastervolt
battery chargers are safe to use and it is
even better for the batteries themselves.
The charge voltage is regulated in accor
dance with the battery temperature to
ensure the batteries remain in optimum
condition, increasing their lifespan.
The 3-step+ charging method ensures a
monthly absorption cycle so the battery
I sometimes have a limited fuse
rating via the AC grid. Can I still
use a large battery charger?
Yes, you can
All Mastervolt battery
chargers and Combis are fitted with the
latest electronics, reducing their power
consumption by about 40 % compared
to conventional battery chargers. For
example, the power intake of Mastervolt
12-volt battery chargers is summarised
below for 230 V models. The levels of
current specified are relevant to maximum
capacity operation, i.e. at the moment the
battery charger supplies its full capacity.
In addition, each battery charger with
a charge current higher than 15 A (12
V) can be equipped with a remote
control panel. This is not useful for
smaller battery chargers as the current
consumption will be minimal. Using
a remote control panel allows you to
further reduce the outgoing charge
current, as a result of which the battery
charger uses even less power from the
grid. This prevents fuses from blowing,
but will slightly increase the charge time.
EasyCharge Portable 1.1A
EasyCharge Portable 4.3A
A 200 Ah Gel battery requires a battery
charger of at least 25 amp. When
multiple loads are connected during the
charging process (e.g., heaters, refri
gerator, lighting) a battery charger of
50 amp is needed. If the battery charger
is powered via a generator instead of
the grid, a battery of 100 amp would be
recommended. A larger battery charger
shortens the charge times and allows
the generator to operate for shorter
periods. This enhances comfort levels
and is better for the environment.