6s also need high voltages to get them truly full. Regular RV converters cannot do the required voltages.
I am able to look after my batteries- any brand, any type, because I have an adjustable voltage charger that can do the specified voltages and has enough amps to keep generator time to a minimum when off grid.
It is a nuisance that you have to get a second charger, but it also gives you redundancy while camping, which is a "good thing."
I use the PowerMax "adjustable" which several forum members are also using, but there are other makes of adjustable voltage chargers that some fellows have that get it done too.
