Deep Cycle Batteries - Super Start Marine (Oreilly's) vs Duralast (Autozone)

Florida Native

Active member
Meh, I wouldn't spend real money on Odysseys again. Talk about a battery that needs to be coddled. Next time I buy batteries I'm following the general advice to spend the least amount and plan to replace often.
I have also had poor luck with Odysseys. Not really available in large capacities (I don't think), but I have had very good experiences with Panasonic VRLA AGM batteries. They're the only ones I use in my motorcycle(s) anymore.

-Mike

Sent from my SM-G950U using Tapatalk
 

dreadlocks

Well-known member
Dont bother with AGM's for a trailer unless your a full timer, they are allright for a truck that always leaves em fully charged once engine is turned off but in a recreational trailer your not going to recharge it through the factory trailer wiring from the engine..

Unless you pamper an AGM and provide it with good, reliable charge soources they are likely to reach an unrecoverable state far before a true deep discharge FLA battery.. Dual 6v is totally the way to go, you get the thickest plates and most lead for the least money.. you dont have to worry about one failing, they fail together.. its just one big battery when you put em in series.. and if you have a single 12v battery and it fails your outta luck tooo so @hemifoot's argument against 6v is nonsense.

If you cant do dual batteries, then I'd buy a Trojan 12v over any AGM.
 
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Ducky's Dad

Explorer
Meh, I wouldn't spend real money on Odysseys again. Talk about a battery that needs to be coddled. Next time I buy batteries I'm following the general advice to spend the least amount and plan to replace often.

I have ranted against Odyssey often enough, but I feel a need to stand up for them now. I absolutely will not buy another of their Grp 31s, because they are fussy, high maintenance and short-lived (sample of three). But as bad as the Grp 31s have been, the Grp 34s and Grp 34/78s have been mostly great. And their customer service is great.

My current battery setup in the Power Wagon is a Grp 31 vMax Tank Grp 31 AGM dual purpose for starting and a pair of vMax Grp 34 AGM deep cycle for the house batteries. These replaced a series of Odyssey and Optima batteries in that truck. So far, so good. The Northstar Grp 31 DP in the Tundra has been absolutely trouble free and outlasted the Odyssey in the other truck, both installed same week. The other line of batteries worth looking at is Full River. I'm pretty much locked in to AGMs for house batteries because mine are mounted on their sides and space is tight.
 

DaveInDenver

Middle Income Semi-Redneck
Side mounting of course dictates AGM, there's no way around that.

I have two Odysseys, a group 25 and its mirror group 35. Both are the same age, almost 4 years now, so out of warranty. One is holds fine and one is struggling. Following Odyssey's reconditioning stabilized it but didn't recover it. It settles to about 12.6V after good topping/conditioning charges and that's something I'm doing about every other week now.

I've had to keep my ML-ACR disconnected otherwise after a couple of hours parked it'll cycle on and off until the weaker battery no longer holds >12.7V long enough (I think 10 minutes or whatever the sample period is) for it to snap them back parallel. That's about a day sitting parked. At that point the ML-ACR remains open fine. Pretty clearly the stronger one is maintaining a surface charge is all that's happening. When I'm camping and the fridge is running the batteries disconnect within a few minutes of stopping.

The good one sits at 12.8, 12.9 volts for weeks no problem as long as I disconnect them immediately after parking. But it's in the redundant slot so doesn't have the draw of the truck on it constantly. My speculation is they are poor dual use, thus small sustained draws like ECUs are hard on them.
 
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john61ct

Adventurer
Yes Northstar are also an excellent maker.

Deka makes great FLA, also GEL, but their AGM are meh.

But FLA will always beat AGM robust stand up to abuse, not fussy about precise chatging criteria.

But yes these comments only applies to deep cycling usage, nothing to do with cranking a motorbike.

And yes if you're not able to give proper care, don't spend more than minimum.

But for deep cycling you really do need a deep cycling batt, and $1 / Ah for Deka's good FLA GCs, can't get better value than that anywhere
 

hemifoot

Observer
not arguing against 6 volts,not nonsense,it's just my choice on how i chose to power my rigs.it works for me and that's all that really matters.batteries don't fail all at the same time,that's nonsense.
 

dreadlocks

Well-known member
they do when you wire em all together, unless you happen to catch it immediately by luck one bad battery will kill a whole bank of batteries very quickly as all the rest desperately attempt to equalize with a battery thats not their equal.. when you got a bank of batteries, you buy em all at same time and replace em all at same time.. mixing and matching different batteries of different ages is just going to lead to more problems down the road.
 

john61ct

Adventurer
Especially with series-wired.

Parallel is more forgiving for cheapo batt swapping,

but if spending a lot, past 3 units then balancing issues kick in
 

dwh

Tail-End Charlie
its just one big battery when you put em in series.. and if you have a single 12v battery and it fails your outta luck tooo so @hemifoot's argument against 6v is nonsense.

I disagree; it's not nonsense - in his situation. Context.

And you said it right here in this quote; "if you have a single 12v battery"...

He doesn't.

So if your going to run two batteries anyway (which you must do to get 12v out of GC), then having 2x12v instead of 2x6v does provide a valuable redundancy. As Verkstad just pointed out, a single dodgy cell will put you out of business when you only have 6, but if you have 12 you can just halve your capacity and soldier on.



<general untargetted rant>
Running strings of 6v FLA deep cycle batteries is certainly an effective deep cycle setup (though strings of 2v is even better). But it is rarely a practical solution for most of the "overland" crowd.

Powering a travel trailer is one thing, but recommending a pair of GC batteries to a guy looking to power a fridge in a frikkin Samurai would just be unforgivably stupid...and would be a clear indication of someone who is more focused on talking than on listening.

I'm a notorious motor-mouth and make no apologies for that (marketing research shows that people have to hear something a dozen times before it sinks in)...but I do try to address the question that was actually asked.
</rant>
 

luthj

Engineer In Residence
For a read on what is usually inside those "dual purpose" batteries, take a look over here.

TL;DR most are just starting batteries with thin spongy plates, poor separators, and active lead. So don't pay much for one, and go for the heaviest you can find per dollar.

Dual Purpose vs. Deep Cycle
Pictured here is the lab rated difference between a golf cart battery and a Dual Purpose Group 24, 27 or 31.
505112

AGMs can be made so that they have very high CCA (low internal resistance and plate area) and also cycle deeply without issue. They are expensive (like lifeline).
 

john61ct

Adventurer
If you want to live for extended periods off grid, running a fridge without a genset along, does require a robust deep cycling bank. Personally I think 100Ah would be too small, unless very reliable input most days from lots of driving or say 200W of solar in bright conditions.

Yes of course having a tiny vehicle is a handicap needs working around, but ignoring the issue would be a disservice.

I do admit when I think Expedition truck, I am usually thinking along these lines
Action-Mobil-Atacama-7900-Expedition-Vehicle-5.jpeg
 

john61ct

Adventurer
And there are 12V batteries suitable for deep cycling,

just not either of those two

and not as good value relative to GC's for those with more space.

Odyssey's PC-2150 for example, exception that proves the rule that "dual use" can actually live up to the hype.

Here's a great resource on the topic in general, everything on his site about electrickery is worth close reading.

 

dreadlocks

Well-known member
Two 12v batteries in parallel will also kill eachother when one goes bad, you have one battery drawing down the other and the other never gets fully charged, yes not as quickly as in a series but they still will unless your isolating and testing the batteries regularly.. OP is in a trailer, he's not running a house battery and a starter battery separate with an isolator, and a single 100AH setup is honestly not enough for even just a fridge, its bare minimum at best.

I digress on this point but I still stand by nonsense statement.. dual 6v GC batteries are far superior than dual 12v car batteries for a trailer in almost every way.. if your only argument is "but I can still use one if the other dies" then your just grasping for straws to justify your own decisions.. spending more money for worse results so you can justify a scenario that isint happening is nonsense.
 

luthj

Engineer In Residence
There are some 6V group 24 batteries that showed up in a quick google search. The odds are they would have much thicker plates. May not be worth the extra cost.
 

dwh

Tail-End Charlie
OP is in a trailer, he's not running a house battery and a starter battery separate with an isolator, and a single 100AH setup is honestly not enough for even just a fridge, its bare minimum at best.

The OP has a pop-up trailer that doesn't get a lot of use. He mentions nothing about a fridge. In a later post he mentions needing one battery now for an upcoming trip and it needs to fit the existing battery box.

This is what I mean about answering the question that was asked.


I digress on this point but I still stand by nonsense statement.. dual 6v GC batteries are far superior than dual 12v car batteries for a trailer in almost every way...

Yes, they are. They just aren't PRACTICAL in many situations, which renders their electrical superiority irrelevant.
 

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