# Can I have 2 batteries hooked together for 12V system?



## donovan612 (Mar 25, 2010)

I wanted to hook two batteries together so I don't have to switch all the wires when one dies. Is this possible?


----------



## Troutman3000 (Mar 25, 2010)

Yeah - look into the electrical section. I believe you run them in parrallel.


----------



## poolie (Mar 25, 2010)

Oh yea. A pretty good number of people here have two (or more) batteries running in parallel. The simple approach is just to wire pos to pos and neg to neg. A little fancier way is to install a switch, a quick google search found this one https://www.pirate4x4.com/tech/billavista/dual_battery/my_dual_battery_setup.htm 

The switch allows you to use battery A only. Both batteries A & B (in parallel) or battery B alone.


----------



## bAcKpAiN (Mar 25, 2010)

Yes, I have two batteries that are connected into essentially one large 12V battery. I got some 6Guage wire and attached battery terminals to each end and connected the two batteries Positive to Positive, and Negative to Negative. I treat the set as oe large battery. I connect positive leads to the positive of one battery and the negative leads to the negative terminal of the other battery.

There are a few things to make sure of if you want this setup to work for you. #1 make sure you have as close to identical batteries as possible. At the very least have the same size. #2 Make sure you keep your batteries on some sort of maintanance charger. I use a Guest 6A single cell charger and it keeps my batteries at 13.1V. If you for some reason can't keep some sort of a charger/maintainer on the circuit make sure to disconnect the batteries from one another during storage. One will feed off of and ruin the other if this percaution isn't followed.
If I can get some pics of my setup I will post them for you. I run everything off of this 2 battery bank for my boat and have never had a problem.


----------



## donovan612 (Mar 30, 2010)

Thanks for the tips. That will help a lot.


----------



## russ010 (Mar 30, 2010)

If you have them sitting side by side, use the largest gauged wire you can find. The larger the wire, the more juice you can get and they are more efficient.

I would use atleast 4ga wire, but I would personally go with 2ga or larger


----------



## MeanMouth (Mar 30, 2010)

This also might help along with the other good information that has been posted; this is a diagram I made showing a 12 Volt motor, using two batteries which are wired in parallel for double the fishing time


----------



## captclay (Apr 11, 2010)

One thing to watch for is if you have electric start and one of the batteries is for starting you dont want to run them both down and not have enough power to start the motor when its time to go home.If thats the case you will want to put in a battery isolator or a switch to keep your starting battery from draining.


----------

