Finished the 24 Volt deep-cycle system ON HOLD !!!THESE TWO BATTERIES NEED TO BE IN PLASTIC BATTERY BOXES - DESIGN BEING REVISED DO NOT BUILD AS SHOWN . Ordered 2 at Walmart for $8 each.
I finished my project which is a charging system based on two group 24 Maine deep cycle storage batteries. PM me and I will send you the details to build it. This system meets the needs for many of us but provides nowhere near the daily output of a gasoline generator setup.
The system will provide the charger [in this case a Powerlab 6] with 25 amps at 24 volts. It can be pushed to 40 amps if necessary. Ideally it should be used to 50% of capacity, meaning the open-circuit voltage of the deep-cycles is about 12.2 volt per battery. They can be discharged to 80% or about 12 volts. However each cycle run at 40 amps, or each 80% discharge is equivalent to two cycles. If you did both, it would be equivalent to running 4 cycles at 25A and 50% capacity.
I re-charge at home using a digital charger on the 10-amp setting, or 5 amps per battery. In the off-season or periods of low use they are on a 1.5 amp "maintainer", the Schumacher XM1-5. Just don't leave them unattended on an old analog 10 amp charger. PM me and I will send you the details to buy the parts and build it. The parts are: heavy-duty DPDT center-off toggle, 10 position terminal strip and 10 gauge primary wire and terminals. Note the catch tray ! I already had a brand new Exide 24 EV belch acid on a 1 amp initial charge. The parts dealer replaced it and the replacement is OK but these things CAN for unknown reasons, expel acid. Add a box of baking soda to the parts list. A very useful tool is a DC clamp-on current meter such as the UNI-T #204, $52 on Amazon.
I will add more photos soon. I added the "details of construction"; they were in pdf but I found an online service that converted it to jpg, unfortunately it only converted the first page of 3, gak ! write me for the entire thing.
Also, if I had it to do over again, I would seriously consider using AGMs ,[probably the larger size 31] because they are sealed & unlikely to spill acid and should be able to supply 40 amps without degradation.