Modifying for 2 batteries
I want to add a second battery. The current one is a 12 V 60 Ah, so I wanted to add another one of same type, in parallel, which would bring it to 12 V 120 Ah. The dealership told me to use instead 2 batteries of 6 V, in series. Those batteries are 130 Ah.
I am wondering why? What is the benefit? If I go with their solution, I will have to buy 2 new batteries, instead of 1. And those batteries cost over 200 $ each. And at the end, the same power output.
Anyone knowledgeable about this?