batteries for trolling motor

[skipg]

Hi,
I have a new 22ft Suncatcher pontoon. Just ordered a MinnKota 24 volt trolling motor.
My problem is that I will need two 12v batteries and the Suncatcher only has room for one in the battery compartment.
I had a friend look at it and he said I could possibly stack one battery on top of the other if I could separate them. I don't know if this will work or not. Also, I'm trying to find smaller batteries with enough power to work.
Any suggestions would be appreciated.
Thanks,
Skip

 

[alldodge]

Not knowing exactly how yours is laied out

If your mounting the troller on the stern, Might thing about adding a bat box and place your start bat in it. Most I've seen mount it on the bow, and then place the bats under the forward seat.

 

[skipg]

it's a bow mount, and if I can figure out a way to squeeze 2 batts in the compartment I'll do that.

 

[fishrdan]

Pictures?... What is the trolling motor going to be used for, positioning while fishing all day, moving at the dock, trolling all day long?

The problem with squeezing in 2 batteries is that you'll probably have to go with smaller batteries, less battery capacity, something you don't want to do with a trolling motor.

Putting the batteries as close to the TM as possible is the best option, but you could put a battery at the stern and use heavier battery cable to compensate for the voltage drop. I have a 24V TM on my Crestliner and it's bow battery locker is only big enough for 1 battery, so I put the other battery in the stern, and ran heavier wire for the batteries, 6ga.

Use this voltage drop calculator to find out what size wire you need.

Buy the marine wire and connectors from genuinedealz.

 

[roscoe]

If you have enough "freeboard" (space between deck and water) you could mount a box below the deck, and put an access hatch above it.

But that depends on the diameter of your logs, how fast you cruise abound, and how rough the water is that you boat in.

 

[skipg]

Thanks for all the replies. Much to think about.
Also, I have a 24v 80lb thrust trolling motor, what is the minimum size battery I can use? I already have a D34m Optima battery but I see it is only 35AH. So even with two of the same batteries I may be under-powered. Should I look for batteries with a larger AH rating?
Thanks

 

[skipg]

correction: it's 55AH on the Optima battery

 

[alldodge]

You should be ok. If you start running out then need to get something bigger

 

[skipg]

To Fishrdan,
Your post got me to thinking about setting up my batteries the way you have; one in the bow compartment and one in the transom compartment. I also went to the wiring site and applied the voltage drop calculator. My question is:
How much voltage drop is acceptable for a 24 volt system?
I have about 22-24 ft to run the wires and need to decide.

Thanks

 

[fishrdan]

I shoot for 3% voltage drop, which will only occur at the TM's max draw, with the proper sized wire. Under normal operating conditions the voltage drop will be less. 3% of 25V (about the voltage of series TM batteries) is around .75V

22-24' run is 44-48' of wire, be sure to put the total length of wire into the calculator.

I play with the numbers in the calculator to see if I can use thinner wire, or if I need to use what was recommended...

Be sure to fuse both batteries + terminals with a 50 or 60 amp fuse/breaker, for protection. I use the cheap $5-10 breakers without issues. Be sure it use manual reset breakers. DON'T use auto-reset breakers.