2 batteries for a 12v trolling motor

[stratos bandit]

I had a 24v TM that kicked the bucket and for financial reasons, replaced it with a smaller, 12v TM.  Now I have 2 trolling motor batteries. 

Is it possible to wire the 2 batteries together and function as 1 "big" 12v battery?

Are there pros/cons to this?

[Ron Fogelson]

Yes but make sure you know what wires are running to what battery

24 volt is one wire running from one of the batteries positive terminal and one wire running from the negative terminal of the other battery with a jumper wire running from the negative wire from the 1st battery to the positive of the 2nd battery


When running two batteries for a 12 volt just run both wires from one battery and have jumper wires running from the 2nd battery one from positive to positive and one running from negative to negative

This will give you longer run time than doing one battery alone but still not as long as running a 24 volt system as the 12 volt will need more power and work as efficient as the 24v

I used to do this on my 1st bass boat worked fine, god luck   

[bassadict69]

That is how I have mine ran...with only one battery, my "too small" trolling motor would drain it after about a half day fishing because I was having to run it on higher speeds.

I ended up running two batteries in parallel with each other as Ron said, & can now fish for 2 days with the same charge!

[stratos bandit]

I have either 6ga or 8ga wire at home, can't recall which at the moment.  Is this sufficient for connecting the 2 batteries to run them parallel?

[BassBUFF]

Ethe should work fine. Just make sure you get good solid connections on the erminals you crimp on.

[Flyrodder]

My new Tracker has 2 batteries, one for the trolling motor and one for the engine. I've heard some people connect the 2 together and are able to use the trolling motor for a much longer time.  Is it wise do do this since? My only drawback is I dont have easy access to electricity where I park my boat.

[stratos bandit]

I bought to battery terminal cables that are 4ga.  I figured the heavier gauge would lose less current between the 2 batteries.  If it ever stops raining......I'll go wire the 2 batteries.

[caddobass]

Wish I had read this before screwing up my 12v. Now it is costing me $160 to repair my 12v. "Of all the things I've lost I miss my mind the most", my son told me I was doing it incorrectly. Father knows best, I don't think so.

[Ron Fogelson]

My new Tracker has 2 batteries, one for the trolling motor and one for the engine. I've heard some people connect the 2 together and are able to use the trolling motor for a much longer time.  Is it wise do do this since? My only drawback is I dont have easy access to electricity where I park my boat.

I wouldn't because 1 your cranking battery isn't a deep cell 2 even if it was a deepcell if you should happen to use the TM more that you thought you could end up not having the juice needed to crank the big motor when needed.

When I had my 640 with a 12v I changed out the crank for a deep cell and added a deep cell for the TM, when I got my 929 with a 24v TM I swapped the crank for a deepcell as well gves me more piece of mind when running light/depth finder/live well.

[Donald Garner]

I've often wondered why there is only (1) battery to supply cranking power to the Outboard and all the electronics and livewells.   

I was thinking of adding another battery and just having my outboard hooked to
the cranking battery only. 

I know there is the added weight but it would beat having a outboard that wouldn't crank when needed after a long hot day on the water.

[Creel Limit Zero]

I know what you mean Donald, this time of the year, I pretty much run the livewells non-stop.  Heat is so much, I don't want to lose any of those  in my live wells.  I've been thinking about moving the live well wires to the deep cells, as I never run out of juice from the Trolling motor, no matter how much wind there is.  Those AGM batteries running the Minnkota 80 just never seem to run out of juice...  I'll get home after a full day on the water with plenty of wind and the batteries will read 70% when I check them. 

[BassBUFF]

I'm with Ron on the Dual-purpose for the cranking battery!

[garland7]

Running 2 batteries on a 12 volt system will give you juice for a longer time. Keep in mind that batteries get a memory, so charge them just after use, or run them way down.

[traveler]

Garlin,  not on lead/acid batteries.