I have a 12 foot aluminum v-bottom with a new 40lbs thrust Minn Kota trolling motor.  I also have a 3 horse johnson but until i finish fixing it up, the Kota will be my primary propulsion system for me.  I fish on a local 199 acre lake.  What size battery should i use for the 40lbs thrust trolling motor to maximize my time on the water?  Thanks much

The biggest one you can find and since it's the only way you got to move you better get a second one as a backup, and a paddle. 

Hello from up in Otsego County and Welcome to Bass Resource ~

 

I agree with @cfalco - I run two Mod 31's in this Old Town.

And just as important as the battery is a decent charger - I use a couple of these, they work well

Charge yours back to full as soon as possible and you'll be good to go.

A-Jay

One of the 500Ah from a electric pallet jack, probably only weighs about 300 pounds.

 

1 minute ago, Way2slow said:

One of the 500Ah from a electric pallet jack, probably only weighs about 300 pounds.

 

A-Jay

Actually, the biggest you feel like you can handle, but no matter what you get, you will need to learn how to manage its use or plan on doing some paddling.