Charging 2 battery setup?

[Capt Sully]

my set up is too simple, I have a smart charger on 2 batteries and I bring along a jump box.

[RonKMiller]

As long as your batteries are the same brand and age there is no reason you can't charge them at the same time, your charger will simply think that they are one "large" capacity battery.

I have my boat parked remotely with a 15 watt solar panel and a charge controller. The panel is in shade all the time yet still produces enough current to keep two rv house batteries fully charged - along with a heavy duty deep cycle combine battery I use for the boat's electrical system. I have quite a few extra lights on my boat that are frequently used over night, hence the choice of a deep cycle.

While being towed or under way I have 90 watts of on board solar panels mounted on the roof - also connected to a charge controller - to charge everything up during the day, when demand is limited.