Before you read further, CONFIRM WITH YOUR MANUAL FIRST BEFORE TRYING ANYTHING!
from what I can tell based on the pics of the charger and what is included, there appears to be some sort of power port next to where the AC wire plugs in, correct?
That appears to be where you would run that one cable that has the banana plugs on it into a DC based power source like a power supply unit.
Now, since you want to hook to a marine battery, you would need clamps that the banana plugs would plug into, or just make a jumper of sorts that will plug into the banana plugs and have the clamps attached to that.
Again, CONFIRM WITH YOUR MANUAL!
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