Goal Zero Vs. Dual Battery Vs. Solo Group 31

Which setup?

  • Dual Battery

  • Goal Zero

  • Group 31


Results are only viewable after voting.

john61ct

Adventurer
As far as charging rate goes, .2C does no harm, but .4C is optimal.

For top quality deep cycle AGMs.

So a 400AH bank should ideally get a 160A rate, but can get by OK with only 80A.

Just as true for all of them.

Again, nothing to do with Optima, their TPPL spiral wound tech (invented by Enersys) is completely different, and Johnson Controls just doesn't have any credibility in the deep cycling segment of the market.
 

Ducky's Dad

Explorer
Optima is irrelevant to deep cycle usage, since Enersys sold them off they're good dual-use Starter batts that's all.
Optima would disagree with you on that point. They still make two separate battery types, starting batteries and dual purpose (deep cycle) batteries). Are they true deep cycle? No, but neither are Odyssey or Northstar or Deka, even though they all claim to be dual purpose with deep cycle capabilities.

It is just silly to talk about a charger branded by a batt vendor, just, why?
No need to get your panties in a bunch over a discussion of chargers branded for battery makers. I had mentioned them because they are supposedly optimized for those battery brands, but some of it is admittedly hype. The first gen Odyssey chargers were manufactured by Schumacher, don't know who is making the second gen for them. I also have smart chargers by Ctek and Optimate (not Optima), plus two versions of the Odyssey smart chargers, plus old dumb chargers from Craftsman and Schumacher, and some small solar panels from Noco. Not a single one of those has been able to keep the Odyssey Grp 31s happy in intermittent use. The Northstar just keeps chugging along with no attention.
 

john61ct

Adventurer
Optima would disagree with you on that point.
Of course they would. It's Johnson Controls BTW, would never buy any of their batts for deep cycling usage, and they probably make 80+% of batts made in the NA market, zero credibility on the topic of deep cycling afaic.

> Odyssey or Northstar or Deka

As I've stated the first two make great AGM, only. And Deka makes great FLA and pretty good GEL, but their AGM are not great for deep cycling use cases, perhaps roughly similar lifespan at 50% DoD to Optima these days.

When Optima were made by their inventor Enersys they were a much better product.

Same with Diehard Platinum back in the day - I think Sears gave the contract to JCI in fact, thus meh. . .



> Ctek and Optimate

decent for storage, but never seen a charger from either that puts out enough amps for a normal deep cycling bank while actually **in use**


You may think your Northstar is "just fine" at low amp rates, and if only cycled down to shallow DoD, it may well be.

But if it's getting drawn down regularly to 30-50%, it will live hundreds of cycles longer charged at .3-5C rather than below .2C.

Also, if your vehicle alt is a significant source of charge overall (which is very rare in most deep cycling usage), check to see if one is putting out a better charge profile than the other, that (or any number of other variables) could account for the difference.
In any case, the PC-2150 is as fine a G-31 AGM as you'll find worldwide. Same with Lifelines equivalent, maybe even a bit more so? Pricey yes, but for those that **actually need** AGM specifically, at least you get what you pay for.

Here is a great resource on this topic, everything Maine Sail writes about DC Electrics is well worth studying

https://marinehowto.com/what-is-a-deep-cycle-battery/
 
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Ducky's Dad

Explorer
Same with Diehard Platinum back in the day - I think Sears gave the contract to JCI in fact, thus meh. . .
The old Diehard Platinums were rebadged Odysseys, confirmed by a phone call to Odyssey. When Sears terminated that contract, they switched to Northstar, confirmed in a phone call to Northstar. But none of the current Diehards that I have seen has the specs of either the old Platinums or the current Northstars. Sears is on my fecal register because my first Diehard Platinum Grp 31 Marine (Odyssey) failed just before the three year warranty ended, and I got into the Sears store three days after the warranty expired. Sears would not do anything, but Odyssey stepped up and replaced it. The replacement lasted two years and failed to take a charge, even on their own (Schumacher) charger, so they replaced it again. That's two Grp 31s in five years, with regular maintenance and a log of driving vs parked vs charge cycles on their charger. That third one is in the truck now, won't take a full charge on any equipment I have, and never gets to 100% SOC except immediately after disconnecting the charger. Let it rest overnight and it's down to about 80% sometimes. Odyssey's customer support is spectacular, but their Grp 31s are a big disappointment.
 

Airmapper

Inactive Member
Believe what you want, but my three Odyssey Grp 31s have been a major pain in the ass, and the Northstar Grp 31 has been perfect. Batteries are in different trucks, but both are parked more than they are driven. Odyssey requires constant maintenance charges, and the current one has been that way since new.

I have not gone to near the effort Ducky's Dad has, but it's been the same with mine. Seems like no matter what I do, how many times I charge it, it always settles to 12.4-ish.

I recently added a small fridge, and I'm worried it won't make it through the night. I ran 10g wiring direct to the battery and still need to drop it to the lowest safety cutoff setting to keep it running if I install it after the truck has sat overnight. I'm probably going to test it this weekend to see if it can make it until morning without spoiling my food.

Never have any trouble with the battery running anything, it's just never "full" and the voltage level is screwing with my devices even though it seems to have ample capacity.

I'm almost to his solution, get me a Northstar and see if some other dope will take this 2150 and the stupid 50 amp charger that won't put out more than 8 amps off my hands. I'm sick of messing with it and wondering if it's charged or not. As it is I have to plug it up every other weekend. Family comes to visit and thinks of all my crap I won't get a decent battery because every time they see it, there is a charger under it with a loud fan blowing.
 

john61ct

Adventurer
Voltage only very loosely correlates to SoC, without extensive calibration, and changes as the bank ages.

100% Full is only objectively defined by Absorb voltage endAmps, as in the example above; Deka's for example is "no further decline in trailing amps for over an hour".

72+ hours of isolated rest later, then you can see what the "full voltage" actually is - and also calibrate specific gravity for FLA batts.

A load test at constant .05C discharge rate down to 10.5V is how (the only way) to accurately judge SoH, residual capacity.

I did not mean to imply Diehard was any good, for many years now not at all suitable for true deep cycling usage, just as with Optima.
 

Ducky's Dad

Explorer
Neither OP nor I have been talking about true deep cycling. His choices were Goal Zero, dual battery, or Group 31. I don't think he specifically excluded true deep cycle, but that was not on his hit list. His current needs don't seem to call for a true deep cycle, and he does not seem to want the complexity of dual batteries, so that would take true deep cycle off the table. He likes Goal Zero, I don't. My vote is for dual batteries, because there are lots of DIY kits to fit duals in a Taco, and I think his best bet is a pair of dual purpose Odyssey or Northstar Grp 34s (if that's what the kits accommodate). I'd rather see him get a single dual purpose AGM Grp 31 than a Goal Zero, and I prefer the Northstar to the Odyssey in that size. He can always add a Goal Zero later. It's a simple decision. No need to make it more complicated than it needs to be for OP.
 

1leglance

2007 Expedition Trophy Champion, Overland Certifie
I get a hefty discount at NAPA, any idea who makes batteries for them or what would be recommended?
I just got a 2017 Taco and I am trying to eval my options...
The goal will be a camper shell of some kind (looking at GoFast, Vagabond, AT or Leer type), running solar and the aux batteries in the bed where the Friday and other power sucking things will live.
Not sure if I am going to put an aux battery under the hood.

My other rig (soon to be for sale) has been running Odyssey batteries with a Ctek dual battery setup that gets power from my solar also. Works great.
 

john61ct

Adventurer
IMO unless "just a Starter batt", means you want deep cycle.

The Yeti/GZ style bigger lithium powerpacks are designed for deep cycling only, and deliver on that, they're just not good value IMO.

OP mentions future solar and a fridge, very heavy usage.

Just ventilation and recharging screen gadgets can use a lot, certainly powering speakers does.

If AGM is not specifically required, pairs of Duracell/Deka GCs are the best value, far more than any 12V automotive group size falsely labeled pseudo "deep cycle" from big box retail. Otherwise Trojan, Crown, US Battery, Superior or Rolls Surette, but pricey.

If AGM is required, then spend the money on Lifeline, Odyssey or Northstar. X2power from Batteries+ is Northstar. Firefly Oasis for unavoidable PSOC abuse, but pricier.

I don't think anything but these choices are good value in the NA market.

I don't believe NAPA sells anything worth considering, likely all JCI made.
 

DaveInDenver

Middle Income Semi-Redneck
I have not gone to near the effort Ducky's Dad has, but it's been the same with mine. Seems like no matter what I do, how many times I charge it, it always settles to 12.4-ish.
never gets to 100% SOC except immediately after disconnecting the charger. Let it rest overnight and it's down to about 80% sometimes. Odyssey's customer support is spectacular, but their Grp 31s are a big disappointment.
I have two Odyssey PC1400, a group 25 and a group 35, set up as a typical ML-ACR isolated pair. What I've noticed, and this is unsubstantiated observational, is that they seem to like their bulk charge and float to be on the aggressive side. My belief being Odyssey expects them to be abused and treating them gently might actually be harder on them.

I use 45 A @ 14.8 V for bulk, 14.2 V for 8 hour absorption and 13.6 V float (standard Iota IQ4 profile) when I happen to need a full charge or 13.8 V @ 30 A constant (just a Powerwerx SS-30DV regulated supply) for periodic maintenance float (usually 8 to 24 hours done approx. monthly). This is with the batteries parallel for capacity of ~110 A-hr. I'd expect 45 amps for bulk would be exceptionally harsh for a single PC1400.

Odyssey recommends a 2-step profile, 14.7 V @ min of 0.40 of C10 and a 13.5 - 13.8 V float. Now at 3 years old they settle at ~12.65 V and ~12.8 V, which has been the case for about 2.5 years. Odyssey suggests in their procedure for recovering a deeply discharged battery that you may use up to 15.0 V max but I haven't felt the urge to be more aggressive for maintenance purposes to test if that's true or not.

They initially settled above 12.9 V but dropped slowly during over their first few months of service to their current points. Odyssey says to expect 12.84 V at room temp for a 100% SOC. Nothing I do seems to affect them up or down significantly at this point and I don't see any real reduction in useful capacity (I get about 35 - 40 A-hr consistently from the aux one running my fridge). Although the main one (12.65 V) is my starting battery and is therefore subject to routine small draw of the truck electronics, the ECU, etc. My assumption is this constant trickle discharge isn't doing it any favors.

Have either of you tried doing a deep discharge and re-conditioning as Odyssey suggests? I have not done that with these batteries since I don't have any apparently loss of capacity other
than a slightly depressed OCV, so I don't think the benefit is worth the potential stress on the battery yet.

http://www.odysseybattery.com/documents/ODYSSEY_Battery_Reconditioning_Charge_Procedure.pdf

Doing basically this starting around 3 years old on my previous Optimas seemed to help since the worst I had was a failure at about 7 years and the one it replaced was about 8. That one was ruined when I left it discharged for about 6 months. I had to use the starter to move my truck about a block home from the intersection that the timing chain let loose and forgot to recharge the battery after taking it out. It lasted about 6 month after putting it back in and conditioning it, but the damage was ultimately irreversible.
 
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Ducky's Dad

Explorer
Have either of you tried doing a deep discharge and re-conditioning as Odyssey suggests?
I tried that on the second of my three Odyssey 2150s, without success. All I accomplished was to overheat the battery and cause outgassing, so Odyssey told me to shut it down and give up on that battery. I was using the Odyssey/Schumacher 40-amp charger, per their recommendation. One major difference between that charger and their current models is that the Schumacher chargers had user selectable settings, while the new ones are completely preset and the charger itself decides what the battery needs. It may not be making the best decisions.

I have two Odyssey PC1400, a group 25 and a group 35,
I have had a bunch of Odyssey 1500s (G34 and 34/78), and they are trouble free compared to the Odyssey 2150 (G31).

Now at 3 years old they settle at ~12.65 V and ~12.8 V
My current 2150 is 2.5 years old and usually charges to about 12.65 unless I run multiple cycles with resting/cooling periods between cycles. Sometimes I can get it to 12.8 coming off the charger (every once in a while to 12.85 which is supposed to be 100%), but by next morning it is around 12.5-12.55 and after 5 or 6 days it's around 12.25. My truck's parasitic drain is within spec and I don't usually set the aftermarket alarm when the truck is at home. My house loads, when in use, are handled by a pair of Optima Marine dual purpose 34/78s.

I am currently trying to bring back a ten year old Optima Red starting battery to use as a backup to the tired starting battery in another truck. The Optima Red started at less than 2.0V, so I'll be surprised if I can make it serviceable, but I have had some luck in the past resuscitating old AGMs.
 

DaveInDenver

Middle Income Semi-Redneck
Being down at 2.0 V is pretty far gone, I'd be interested to hear if you get any sort of life back in that one.
 

Airmapper

Inactive Member
Have either of you tried doing a deep discharge and re-conditioning as Odyssey suggests?

I did once and it was a bigger mess than I started with. My super duper Odyssey branded 50 amp charger kicks itself off at 8 amps output and just goes to idle mode, I guess it's all that special programming. Had to pull out a 25amp CTEK just to get it bulk charged then back on the Odyssey to top off. Still settled back to it's usual to 12.4ish.

So that re-conditioning procedure in my experience is BS and just puts me in a bigger pickle.
 

Ducky's Dad

Explorer
Had to pull out a 25amp CTEK
I have a couple of smaller Cteks and have been thinking about the 25 amp as an alternative to the bulky Odyssey chargers. How do you like that Ctek?
 

Airmapper

Inactive Member
Had to pull out a 25amp CTEK
I have a couple of smaller Cteks and have been thinking about the 25 amp as an alternative to the bulky Odyssey chargers. How do you like that Ctek?

Actually I like it a lot, but I don't have the tech expertise to evaluate it properly or discuss it intelligently. I don't mess with questionable batteries a lot, just try to maintain what I have.

On anything but that 2150 just clamp it on and let it work, but until I got the actual Odyssey charger (which I suspect is faulty somehow) it's the only charger I own that will still keep charging a 2150 in absorption phase long past where others quickly claim it's full. That said the Odyssey charger stays on absorption longer still.

It also has an extremely handy power supply mode, I use it as that a lot.
 

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