So i posted a thread a little while ago about my trolling motor going dead on me i replaced the piece i thought was the issue turns out that was not the problem the problem was the battery. So this is my first boat that doesnt run a small trolling motor off one battery i recharge so i really didnt know anything about it all electrical isnt my profession i specialize in highway and superstructure. So after another day on the lake with my friend when the trolling motor slowed again so after messing on the lake we realized the battery was the problem, when i bought the boat from the dealer he told me that the starting battery was the right one an the left one was a deep cycle. the way he made it sound the starting marine battery cranked or charged the deep cycle. When the outboard isnt running the volts read 12.4 on my fish finder when it is running 14.5 avg. So we switched and ran the trolling motor off the full smaller battery for the day and put the deep cycle on the finder and motor and it read 9.0volts but after running the motor it was up to 11.0. SO now the help i need is there anyway i can connect them into a battery bank? so that they are connected so when the motor is running it cranks or charges the batteries? the motor charges the battery since it went from 9-11 after only a few min of running. IS there anyway to connect them and how and the motor and trolling motor both have their own pos an neg connections. would i connect them both to the same battery and then attach the second battery to the first so they draw power of both. I have no idea here and so far the internet has been more confusing i dont want to have to charge the trolling battery every time i bring the boat home especially if i take a week long trip out of state camping.