Best Group 31 AGM Starting Battery out there.

[STRETCH1]

I saw some older posts but I had a discussion with someone about what is the best AGM Starting battery out there (no Lithium), all sources point to the X2 31M Battery (SLI31AGMDPM X2Power BCI Group 31M 12V 100AH 1150CCA AGM Deep Cycle Marine & RV Battery).

Is anything out there better than this in Group Size 31?

SLI31AGMDPM X2Power BCI Group 31M 12V 100AH 1150CCA AGM Deep Cycle Marine & RV Battery

[catdude28]

Odyssey group 31. X2 is fussy about charging for some

[armond]

Odyssey 31

[DBolton]

My X2 has been a beast for the last year. Hope it continues to perform. No charging issues here. Used a Minn Kota 460PC and recent switched to a PowerHouse Lithium charger 12/36v and both have worked flawlessly. It runs 3 Helix 12's, all boat accessories, Mega 360, ethernet, etc. for 8 hours and cranks instant when you turn the key.

[06 SB]

The Northstar 31 has been great for me. I know it is either made by Odyssey or X2.

[STRETCH1]

thanks.

[STRETCH1]

Looks like the Odessey and the X2 and the Northstar are the same battery. They have the exact same specs which is very unusual unless they are the same battery. I looked at the X2 at Batteries + and the different stores near me have about a $100 price difference!

[MichaelJ3]

FWIW, I just warrantied a 46 month old X2 (Northstar) GRP 31.

Always charged it w/ my DualPro 15A Charger immediately upon return from any day on the water.

Guy at Batteries Plus said it was showing 702 CCA on their tester.

They replaced it free with a brand new one…so, if I get 4 more years out of this one, I’ll feel good about it.
It is a beast when new and can run my pumps and electronics all day and still start the engine when time to head in.

Ironically, my boat came factory with a flooded GRP 27 Interstate for starting/accessories, and two GRP 31 AGM interstates for the trolling motor. The starting battery got replaced after 3 years with the X2 Power Grp 31, replaced per above.

The trollers lasted 8 years, actually still test good, but I’m replacing them before the season, as I don’t want to wreck a good day on the lake.

By this experience…should go with AGM interstates again for the troller, but I’ve heard they are not good now. Replacing the trollers with Continental GRP 31 AGM’s as my dealer sells these and says they are fantastic, have a 36 mo non pro-rated warranty, and he said the warranty service is top notch from the distributor. Sometimes service is where it’s at…time will tell.

[mactlman]

FWIW, I just warrantied a 46 month old X2 (Northstar) GRP 31.

Always charged it w/ my DualPro 15A Charger immediately upon return from any day on the water.

Guy at Batteries Plus said it was showing 702 CCA on their tester.

They replaced it free with a brand new one…so, if I get 4 more years out of this one, I’ll feel good about it.
It is a beast when new and can run my pumps and electronics all day and still start the engine when time to head in.

Ironically, my boat came factory with a flooded GRP 27 Interstate for starting/accessories, and two GRP 31 AGM interstates for the trolling motor. The starting battery got replaced after 3 years with the X2 Power Grp 31, replaced per above.

The trollers lasted 8 years, actually still test good, but I’m replacing them before the season, as I don’t want to wreck a good day on the lake.

By this experience…should go with AGM interstates again for the troller, but I’ve heard they are not good now. Replacing the trollers with Continental GRP 31 AGM’s as my dealer sells these and says they are fantastic, have a 36 mo non pro-rated warranty, and he said the warranty service is top notch from the distributor. Sometimes service is where it’s at…time will tell.

interstate 27 flooded deep cycles have been nothing but awesome for me over the last 20 yrs. I would look at the duracell ones at sams club made by deka today though. interstate isn't what it was under johnson controls. walmart has decent ones also. 29 series have been very good at walmart

[zelmo]

I put in the Duracell Marine AGM 31 from Sam's as my cranking/electronics battery in 2018 after I upgraded electronics and got stuck on the water with the old maintenance free 24. Haven't run out of power on the water since. I am going to do some testing to make sure it is holding the charge as it is getting a little long in the tooth but that is just for peace of mind.

If you are lucky you might catch it on sale, making the price even better.

[catdude28]

Looks like the Odessey and the X2 and the Northstar are the same battery. They have the exact same specs which is very unusual unless they are the same battery. I looked at the X2 at Batteries + and the different stores near me have about a $100 price difference!

Enersys, the parent company of Odyssey, bought Northstar a couple of years ago. Hard to tell if the X2/Northstar is now identical to the Odyssey 31 AGM. Weights are different, casing is a bit different. In any case, there have been many posts on BBC over the years of charging issues with the X2/Northstar and the Dual Pro chargers. Irrespective of the brand of charger that you have, it is a safer bet to go with the Odyssey IMO.

[jjue1979]

I put in the Duracell Marine AGM 31 from Sam's as my cranking/electronics battery in 2018 after I upgraded electronics and got stuck on the water with the old maintenance free 24. Haven't run out of power on the water since. I am going to do some testing to make sure it is holding the charge as it is getting a little long in the tooth but that is just for peace of mind.

If you are lucky you might catch it on sale, making the price even better.

It sounds like you are 3 years ahead of me on this one--I'd like to hear the results on the battery test.

[STRETCH1]

It sounds like you are 3 years ahead of me on this one--I'd like to hear the results on the battery test.

I have a Duracell 31 AGM that has been in service since 2018. It works fine and I bought it at Sams Club for $178. Never fails to start my 225 Optimax outboard but I am just a little uneasy with it running the electronics and livewells all day that I carry jumper cables and a jump start box with me but never used them. I said screw it since the battery is 6 years old I can afford a new one but wouldnt hesitate to go back with another Duracell from Sams but also would like to just have piece of mind that I could actually take my Jumper cables and Jump box out of my boat.

[zelmo]

It sounds like you are 3 years ahead of me on this one--I'd like to hear the results on the battery test.

Will do. Just be aware that I am doing a simple test without taking it out of the boat. I was fishing on Wednesday and put it on the charger when I got back. Today it was in standby and the starting battery was at 12.887. I am going to test it again later today and then every morning for several days to see if how much that voltage drops. If anyone has another way to test, short of taking it out for a load test, let me know.

FYI, that boat uses the same batteries for the TM . Those were installed in 2019. They don't seem to be as robust as they were so I am testing them also. I keep jumper cables in the boat in case the starting battery needs a jump but that won't do much good if the TM batteries are too far gone. That is why I am testing all of them.

I also have 5 of those batteries in the jet boat that were installed late in 2020. No issues with those either.

[zelmo]

It sounds like you are 3 years ahead of me on this one--I'd like to hear the results on the battery test.

I want to go fishing so I didn't run the test as long as I would have liked.

After the surface voltage bled off the oldest (starting) battery has held at 12.837v for 4 days. Same experience with the newer TM batteries. That leads me to believe they still have enough life left that I am in no hurry to replace them.

After this fishing trip the batteries will sit for about 2 weeks after charging them. I will report back with the results.

[BigCranks]

X2. My type 31 powers all my head units (5), gls 10 module and m360 transducer. I don't run my pumps much at all, but no problems yet.

[k3fishing]

Duracell is a great battery it’s made by East penn. it’s the same as their brand battery but made for Duracell.

[redzone1]

For what it’s worth, I’m on year 5 on my 8 volt Duracell golf cart batteries from Sam’s Club…..and mine are the regular wet cell non agm batteries. I think they are a quality battery

[billnorman1]

Duracell is a great battery it’s made by East penn. it’s the same as their brand battery but made for Duracell.

Yes but it doesn't cost enough. He wants the BEST. I have a Duracell 31 AGM for my 200 four stroke starting battery. I forget how old it is, once in a while I stick a 10A charger on it, but I don't have a charger for it on the boat. It just keeps going and going and going and going....

[JACQUART21]

FWIW, I just warrantied a 46 month old X2 (Northstar) GRP 31.

Always charged it w/ my DualPro 15A Charger immediately upon return from any day on the water.

Guy at Batteries Plus said it was showing 702 CCA on their tester.

They replaced it free with a brand new one…so, if I get 4 more years out of this one, I’ll feel good about it.
It is a beast when new and can run my pumps and electronics all day and still start the engine when time to head in.

Ironically, my boat came factory with a flooded GRP 27 Interstate for starting/accessories, and two GRP 31 AGM interstates for the trolling motor. The starting battery got replaced after 3 years with the X2 Power Grp 31, replaced per above.

The trollers lasted 8 years, actually still test good, but I’m replacing them before the season, as I don’t want to wreck a good day on the lake.

By this experience…should go with AGM interstates again for the troller, but I’ve heard they are not good now. Replacing the trollers with Continental GRP 31 AGM’s as my dealer sells these and says they are fantastic, have a 36 mo non pro-rated warranty, and he said the warranty service is top notch from the distributor. Sometimes service is where it’s at…time will tell.

Not sure if your aware, but there is a well documented issue with the DualPro chargers not fully charging the X2/Northstar 31 agms. Even the newer Deltavolt models that claim to have fixed that issue were being reported as not fully charging those big AGM batteries. I had the issue personally and switched to the MK 460PCL charger. It's a slow death, but basically they only get the batteries to 80-90% charge and over time their capacity starts to suffer. If your not really using a large amount of the battery capacity, you may never even notice the issue.