Not sure what internet you're using that says a single 24v. You need a 2 bank 12vdc, preferably 10a per bank or more.

I don’t know, might be kinda cool to see what happens when he puts 26+v’s through a 12v battery.

It is preferred to charge them independently with 1 bank each, especially if you are running lithiums. It's not dangerous or risky to charge them at -in series- at 24v, the charger , it's just better for the charger to be able to allow each battery to balance without getting cut off.

Two 12-volt batteries linked in series is effectively one 24-volt battery system. You absolutely can charge the batteries this way. It's just not clear to me if this is in any way better or worse than charging them independently on a two-bank system. like I said the internet doesn't seem clear on the matter. Some sites say it's the better way other say it's not, nothing is saying its in anyway dangerous.

First I had heard of it being possible. After googling it last night, definitely lots of conflicting info. I guess I don’t grasp in my head how you can put 24volts into 12v batteries. I understand the series puts 24+ out at the end, but there’s still 2 - 12v batteries receiving 24v when on the charger.