Multiple charge controllers off one panel, different battery types and voltages

[bcjohnso99]

I've searched for and read many articles and forum posts about multiple charge controllers on one panel/array but have not found any that discussed what I am trying to do.

I would like to create a "charge station" at the dock at our new cabin. The dock is about 300 feet from the cabin, so I intend to install a second array dedicated for this purpose.
The batteries to be charged will be:
1) a 12V lead acid deep cycle battery for a water pump and dock lights
2) a 12V AGM deep cycle battery for a small fishing boat
3) a 24V Li-ion battery for a trolling motor on a larger fishing boat

#1 will always be connected, the other two will be connected only when the boat is at the dock.

Given the difference in voltage, it seems PWM charge controllers will not work.

I have not seen a discussion about parallel MPPT controllers for an application like this. Anyone know if they will work?

If so, what voltage would be best for the panel? The higher the better? A multiple of each target voltage (i.e. "24" or "48"?)

And for sizing, would each controller have to be rated for the full output of the panel/array since there may only be one active at a time (i.e. honour the controller rating for the Max PV short circuit current)?

Or is this just pushing the envelope too far?

Thanks in advance,

Brian

[Mike90250]

When you are asking for charging other batteries, your solar array will have to be able to supply that demand. if you can charge the other batteries in the daytime, you won't need to size the permanent battery to be large enough to charge the other 2.

If I was doing this, I would consider :
the permanent battery to be 24V (4 GC2 batteries in series)
and inverter to power a battery charger for the other 2 batteries. Li batteries need special charging conditions, usually only met with their AC charger.