Trolling motor battery run times

[Pikebreath]

I just purchased an 80 lb Minn Kota Terrova. It's a 24 volt system so I will need two 12 volt deep cycle batteries hooked in series.

All my current lead acid batteries are group 29 and 31 types with 90 - 105 amp hour ratings and reserve capacities of 185 - 205 minutes. A couple are about 5- 6 years old so I am thinking of replacing them.

I notice that similar group size AGM batteries such as the Optima Bluetop D31M have 75 Ah and 155 minutes.

As we camp and do a lot of fishing off the grid, battery run time is more important to me than battery life and the number of discharge cycles. My concern is getting maximum number of trolling minutes per charge / outing.

For those of you have run both types of batteries (lead acid vs AGM) do you find that a similar sized lead acids run longer before needing charging than the equivalent group size AGM batteries?

If you go by battery ratings, that should be the case, but does experience bear that out?

[fish99]

Originally Posted by Pikebreath

I just purchased an 80 lb Minn Kota Terrova. It's a 24 volt system so I will need two 12 volt deep cycle batteries hooked in series.

All my current lead acid batteries are group 29 and 31 types with 90 - 105 amp hour ratings and reserve capacities of 185 - 205 minutes. A couple are about 5- 6 years old so I am thinking of replacing them.

I notice that similar group size AGM batteries such as the Optima Bluetop D31M have 75 Ah and 155 minutes.

As we camp and do a lot of fishing off the grid, battery run time is more important to me than battery life and the number of discharge cycles. My concern is getting maximum number of trolling minutes per charge / outing.

For those of you have run both types of batteries (lead acid vs AGM) do you find that a similar sized lead acids run longer before needing charging than the equivalent group size AGM batteries?

If you go by battery ratings, that should be the case, but does experience bear that out?

i purchased the highest amp hour rating I could find.

[Coiloil37]

I had the same trolling motor and a pair of agm group (31?) batteries in my Lund. They never got drained in a day or two of fishing, not even enough to notice any drop in performance and there were many days they saw 10+ hours of use. That said both my 90 and 9.9 outboards charged them so I didn’t worry about it anyway. I always took the boat out of the water and usually remembered to charge it at night but there were many nights I didn’t worry about plugging them in.

Your going to charge off your outboard(s) aren’t you?

[Pikebreath]

Originally Posted by Coiloil37

Your going to charge off your outboard(s) aren’t you?

Thanks for the reply.

The jury seems out on whether deep cycles should be charged from the outboard or not ,,, so I have always kept my trolling motors separate my outboard.

I run a separate battery for starting and have my sonar hooked up to it as well.

Are your batteries dual purpose, that is do you use the same battery(s) for starting and trolling? Is your trolling motor running 24 volts? If so are you using some kind of isolator or combiner?

[fish99]

separate battery for each 150 hp and 9.9 , then 2 - 12 volts for altera . 4 batteries in total for the boat

[Coiloil37]

Originally Posted by Pikebreath

Thanks for the reply.

The jury seems out on whether deep cycles should be charged from the outboard or not ,,, so I have always kept my trolling motors separate my outboard.

I run a separate battery for starting and have my sonar hooked up to it as well.

Are your batteries dual purpose, that is do you use the same battery(s) for starting and trolling? Is your trolling motor running 24 volts? If so are you using some kind of isolator or combiner?

I just ran a 3 bank digital charger. The alternator topped up my starting battery first which my sonar was run off then charged the 24v side by individual battery. When I had ac power I just plugged the cord into the charger and all three were topped up simultaneously.