I thought some of you might find the below link interesting. It applies only to connecting multiple 12v.
batteries (NOT 6v. golf cart batteries). Since most probably won't run more than 2 batteries, of particular
note is the 6th paragraph from the bottom regarding connecting in a "criss cross" manner.
I made the following to illustrate the "criss cross". The battery positives are connected together, as are the battery negatives. This is referred to as "wired in paralel"; which keeps the voltage the same (12V.), but increases the amp/hours available. The "load" (and charging source) are connected - positive to one battery and the negative to the other. This will allow the batteries to discharge equally and yield better performance.