D grim

I do a lot of overlanding and recovery work all the batteries are charged thru isolators with a heavy duty alt the way I have them set up is I can call on just one or two three or all four at once if I need the amps like to weld I was wondering if there is a easier way to charge them than using isolators

my question is how do you charge the batteries I know there is a few ways to do it I'm using battery isolators to charge four batteries. I'm wondering if there is a better way and seven relays to control witch and how many batteries I'm going to pull power from