Battery

[Rob Lee]

Does your cranking battery and trolling motor batteries have to be identical? All of mine are 12 volt AGM 31M. The only difference is the CCA, Reserve Minutes, MCA are more on the cranking battery. Thanks.

 

[trbr81]

no they do not need to be identical but trolling motor batteries should be same age and capacity

 

[Rob Lee]

Thanks

 

[ChooChooSnakeMan]

I'll post what I believe to be the best practice. A cranking battery needs to be just that, a marine cranking battery is constructed to provide the sudden high amps needed to start an outboard. Trolling motors on the other hand need deep cycle batteries. I undestand that a cranking battery is not constructed to be discharged over a long period of time like a deep cycle battery is. A compromise is to use the dual purpose batteries which are a hybrid construction for cranking or deep discharge. What I'm saying applies to wet cell or AGM, I have no experience with Lithium. My practice the last several years is to use a dual purpose as big as I can afford AGM for my cranking battery since it also powers electronics. I use wet cell deep discharge for the trolling motor. I second the post that you shouldn't mix trolling motor batteries. If you have a strong battery and a weak battery on a 24v or 36v system then the weak battery will pull the other batteries down.