AGM vs Deep cycle marine Trolling battery

[Keith6628]

I have been evaluating batteries myself the last week. I have Optima's and I am considering going back to regular 29's. My Optima 31's are done and are 17 months old. The Optima warranty does not mean they will replace if they go out in less than 2 years. They have to test them and if they are functioning correctly but have just hit the life cycle then get out another $1000 and buy 3 more. Ive been comparing the last few days with anglers I know (some pro's, guides etc.) that either use AGMs or use to use them. My initial info is that the AGMs are lasting about 30% longer than std batteries. If this holds true then AGMs are not worth the expense. I talked to a angler that use to be on Optima's Pro Staff and he said that when he was fishing 50 hours a week his std batteries would get replaced every 6 months. Then when he signed with Optima and went to AGM's they would get changed at 9-10 months. I'm still researching before I decide but initially its not looking good for AGMs

[CatFan]

I have been evaluating batteries myself the last week. I have Optima's and I am considering going back to regular 29's. My Optima 31's are done and are 17 months old. The Optima warranty does not mean they will replace if they go out in less than 2 years. They have to test them and if they are functioning correctly but have just hit the life cycle then get out another $1000 and buy 3 more. Ive been comparing the last few days with anglers I know (some pro's, guides etc.) that either use AGMs or use to use them. My initial info is that the AGMs are lasting about 30% longer than std batteries. If this holds true then AGMs are not worth the expense. I talked to a angler that use to be on Optima's Pro Staff and he said that when he was fishing 50 hours a week his std batteries would get replaced every 6 months. Then when he signed with Optima and went to AGM's they would get changed at 9-10 months. I'm still researching before I decide but initially its not looking good for AGMs

i won't say your numbers are 100% right, but they aren't crazy. I suspect there is a sweet spot where AGMs make $ sense, but it's probably not heavy users or light users.

[Keith6628]

i won't say your numbers are 100% right, but they aren't crazy. I suspect there is a sweet spot where AGMs make $ sense, but it's probably not heavy users or light users.

I wont say my numbers are 100% correct either, this is just a rough estimate from a small sample of 4 to 5 people. Keep in mind that this is heavy usage users also. IDK it's confusing because you try to make decisions that hopefully prevent any headaches during a tournament day regardless of cost.

[Jspell]

Here was my decision to make. I found a cheaper battery Everstart AGM, $122 at Wally world not ideal but will work, 3 year replacement 2 year prorated. Even if they wont honor the warranty and if I can get 18 months or 2 years I am ahead of the game at $122 Last set of tm batteries 14 months and I am sure they cost more than that.

[Duner]

Just my two cents...

First off automotive batteries are made to give you a large burst of amps for a short amount of time. Not good for stuff like trolling motors.

Second not all deep cycle batteries are the same. I'll splane.

Flooded batteries are wet and require service , but like mentioned they will give you the most bang in amps for the bucks spent. They can be used in marine applications if you have proper venting ( they do outgas)

Gel batteries don't require service and make good trolling motor batteries they can be drawn down to 80% of capacity without damage and are made for deep draws and recharging on a frequent basis. This is what I use on my boat.

AGM ( advanced glass matt ) batteries like these types https://under-the-open-sky.com/best-...tor-batteries/ were designed for UPS systems and like to be kept in a full state of charge, they can be drawn down like regular gels, but again like mentioned its good to get them on the charger right away. AGM's will be on the higher side of the price range.

When it comes to batteries you get what you pay for so get the best you can afford. The key to long battery life is not to neglect them. Batteries do have life cycles ( how many times they can be drained and recharged ) so keep that in mind when making your purchase.

[CatFan]

Just my two cents...

First off automotive batteries are made to give you a large burst of amps for a short amount of time. Not good for stuff like trolling motors.

Second not all deep cycle batteries are the same. I'll splane.

Flooded batteries are wet and require service , but like mentioned they will give you the most bang in amps for the bucks spent. They can be used in marine applications if you have proper venting ( they do outgas)

Gel batteries don't require service and make good trolling motor batteries they can be drawn down to 80% of capacity without damage and are made for deep draws and recharging on a frequent basis. This is what I use on my boat.

AGM ( advanced glass matt ) batteries were designed for UPS systems and like to be kept in a full state of charge, they can be drawn down like regular gels, but again like mentioned its good to get them on the charger right away. AGM's will be on the higher side of the price range.

When it comes to batteries you get what you pay for so get the best you can afford. The key to long battery life is not to neglect them. Batteries do have life cycles ( how many times they can be drained and recharged ) so keep that in mind when making your purchase.

The idea that gels and AGMs can be deeply discharged and flooded cells can’t is mistaken. All three battery types suffer large cycle life reductions at deep average discharge levels and on a percentage basis the decrease in cycle life is about the same in all of them. There is nothing magical about deeply discharging batteries. It’s simply the more you use them, the shorter their life. Battery engineers use a 30% or 50% depth of discharge as a design guide for choosing batteries to balance service life and cost, but some people have understood that to mean that those discharge levels are some kind of threshold. They are not. Discharging any of those batteries to 80% regularly is very feasible, but you will see a significantly shorter service life than if you limited the discharge. It’s not altogether different from saying if you only drive your car 10 miles a day it will last longer than if you drive it 75 miles a day.