Concerning regular batteries (non lithium), I see the starter batteries generally have the “MS” designation while the deep cell gave the “DC” designation and then you have dual purpose. Which would you use as starter and which for trolling motor only? Just want to make sure when replacing my bad batteries I replace with the correct battery.

Just keep it simple.

Marine starting battery for starting.

Marine deep cycle for trolling motor.

On the cranking battery, be sure it has enough Cold Cranking amps for your motor.  On the deep cycle, reserve capacity reflects how long it will provide power to the trolling motor the larger the number the longer it will last.

We’ll, my meager electronics, a Lowrance Hook 4 Hdi and my dash including the bilge/live well are also wired to the starter battery…can/should a starter battery handle this as well as the starting process or would I be better off with a dual purpose battery?

A marine starting battery will be fine running that stuff, but if you are thinking of upgrading to bigger electronics, it'd be worth looking into a dual purpose. 

Or,  if you have the room, get a house battery to run accessories !!  On my boat, I have a dedicated start only battery, and then a group 31 house battery for all accessories....then two group 31 batteries for the trolling motor !!  Then always carry a set of jumper cables just in case.  Never wirhout power where needed.  

4 hours ago, Brett's_daddy said:

We’ll, my meager electronics, a Lowrance Hook 4 Hdi and my dash including the bilge/live well are also wired to the starter battery…can/should a starter battery handle this as well as the starting process or would I be better off with a dual purpose battery?

A single battery for your outboard starter, one graph, and pumps/lights will be plenty. I have one cranking size 27 battery for more than that and my last one went for 6 years. Just make sure you keep it adequately charged, and don’t let it sit there all winter in cold temps.

 

Dual purpose or cranking will work. Deep cycles are better used for a trolling motor.

 

As @airshot indicated, jumper cables are always a good backup plan. Or a boost pack like a noco.

Bass boats and batteries have always been an issue.

Today use Marine deep cycle AGM’s, they are maintenance free and hold a charge longer then wet cell plus no corrosive gases.

If you have a 24V TM you should be using 2 each group 29’s minimum prefer group 31’s for longer daily usage.

Cranking battery the Marine AGM cranking battery size 24 should be adequate for your amp draw.

Always add a battery switch to isolate the electronics when charging.

Tom