Sears Diehard Platinum 31M issues

[gravedgr]

I'm here at 0700.
The charger is in my lab at your disposal....

I'll give you a ring in the morning when I head over. I think I remember how to get there, although I'm only familiar with the loading dock. :wings:

 

[Ducky's Dad]

Interesting... By saying 10 amps max, they're basically saying you can't charge them from an alternator (as many could easily push more than 10 amps into a sufficiently discharged battery).

I don't think so. The charging specs are on the last page of each battery's tech data, and the 10amp max is listed under "Battery Charger (Constant Voltage)" rather than under "Alternator." And they also have a recharge time chart showing time to recharge to 90% from a "100% discharge - 10.5 volts" state. That chart shows 35 minutes to 90% on a Yellow D34 at 100amps, so I'm assuming that is from an alternator.

 

[4x4junkie]

I'm curious as well.

I think you've missed the point of a TPPL battery. The whole reason they exist is their ability to accept nearly unlimited charging amperage, shelf life is far superior to traditional lead acid, and size relative to their high-rate discharge and deep-cycle discharge. They are currently the best answer to what most "Overlanding" needs are.

You can certainly get traditional deep-cycle batteries that will deep-cycle as well as TPPL. You can also buy a starting battery will give you high-rate discharge as well as TPPL. But, I have't seen a traditional Dual-Purpose that will do both functions nearly as well as a TPPL.

No, I fully understand what a TPPL battery and it's capability is. Certainly they do have some reasons to exist (a few of which I mention further below), but I disagree they are a cost-effective option for this "overlanding" thing.

Why?

1.
A 4WD truck or RV used for this purpose (typically has a dual battery setup in some form or another) generally calls on the battery to deliver steady currents of 5, 10, maybe 15 amps to run a fridge, lights, water pump, furnace fan, whatever. This means the high discharge current capability of an AGM/TPPL battery typically goes unused (a standard SLI battery very easily handles engine starting duties if the rig has a battery isolator setup).

2.
An average OE vehicle alternator maxes out around 70-100 amps, and if loaded down by a discharged battery, may cut back it's current even further to protect against overheating, so after 10 minutes or so you might have only 30-40 amps going into a heavily discharged battery. Solar setups capable of more than about 20-30 amps are not very common either. So the high charge current capability of the battery most likely isn't being well-utilized either.

3.
I've seen very little recent evidence that these batteries are lasting any longer than more traditional designs, so that in my book is moot as well (once upon a time this wasn't the case).

4.
With dual batteries (especially ones wired straight-parallel like I run), current is shared between them, so each battery has a much easier go of it under a high demand such as winching (the shared current makes the lower IR typically seen in AGM/TPPL designs less important, since each battery only has to output half as many amps to run the same load).



What ARE these batteries good for?
1.
A rock buggy or offroad race car, for it's higher likelihood of being overturned, and the fact these rigs actually could potentially produce enough impact & vibration to damage a conventional battery, unlike a full-bodied 4WD truck or SUV (I don't care how bad the washboard is on that road, it's not gonna break the battery in your 80, 4Runner, Explorer, Suburban, _____(insert favorite SUV here)).

2.
Something unusual in your setup precludes you mounting your battery in a normal upright fashion (though IMO this is an expensive solution to what is normally a problem of poor design),

3.
You absolutely cannot (or refuse to) run dual batteries... As pointed out, a single AGM battery typically does provide better performance for winching and sub-freezing starts than a single flooded (deep-cycle type) battery of the same size.




My current battery of choice (sorry, thought I had already posted this, was another thread I guess):

Costco Kirkland Signature (Interstate) 27M. $80, ~95 Ah, maintenance-free (lead-calcium grid design).
Yes, it's a fairly ordinary battery made by the big evil JC, but the price is right... The last pair of similar batteries I had lasted 4½ years, well inline with recent reports of what all these other ones are lasting.

 

[comptiger5000]

I don't think so. The charging specs are on the last page of each battery's tech data, and the 10amp max is listed under "Battery Charger (Constant Voltage)" rather than under "Alternator." And they also have a recharge time chart showing time to recharge to 90% from a "100% discharge - 10.5 volts" state. That chart shows 35 minutes to 90% on a Yellow D34 at 100amps, so I'm assuming that is from an alternator.

Hmm... That's strange of them to list it that way. They seem to say a 100 amp bulk charge is fine, but they say that you can't allow more than 10 amps in a constant voltage charge. As long as the battery isn't accepting current fast enough to pull the system voltage down, technically an alternator is a constant voltage charger...

 

[BigSwede]

I seem to recall that Optima used to advocate using a 100 amp charger to "wake up" a supposedly defunct Optima battery...now they say you should use one of their ($200) chargers.

 

[Ducky's Dad]

I seem to recall that Optima used to advocate using a 100 amp charger to "wake up" a supposedly defunct Optima battery...now they say you should use one of their ($200) chargers.

I have a couple of Grp 34 Yellow Optimas that I retired because they would no longer start my old truck, even in a dual battery setup. They sat around for a couple of years and then I "woke them up" when I got my Ctek 7002. Optima spec says these batteries are fully charged at 13.1 OCV, and my two retired batteries will now hold 12.85ish pretty well, and they test as good on my load tester.

 

[Herbie]

My current battery of choice (sorry, thought I had already posted this, was another thread I guess):

Costco Kirkland Signature (Interstate) 27M. $80, ~95 Ah, maintenance-free (lead-calcium grid design).
Yes, it's a fairly ordinary battery made by the big evil JC, but the price is right... The last pair of similar batteries I had lasted 4½ years, well inline with recent reports of what all these other ones are lasting.

2 questions: 1) Is CostCo still selling deep cycles? I thought they'd discontinued that. 2) Got a spec on that battery? Last I checked, all the Interstate Deep Cycles were still a wet-cell design, so comparing to a big AGM is a bit apples/oranges since they can't be installed in same places or orientations - I don't really have an option to mount my house battery anywhere except inside the van cabin.

 

[Ducky's Dad]

Is CostCo still selling deep cycles? I thought they'd discontinued that.

Costco selection seems to vary significantly from store to store. The are pretty careful about stocking stuff that appeals to their local market demographics. I can't get a decent battery at my local Costco.

 

[JCDriller]

Man I'm glad I found this thread. I've been trying to decide between two group 34s or one 31. I had no idea 31s were so difficult to maintain. I can't imagine I would be happy with a $400 battery that I was required to plug in on a regular basis just to maintain. Back to leaning towards the 34s again...

Anyone just wired two 34s in parallel for higher capacity but reduced maintenance?? I'm not sure if an isolator is required for my needs.

 

[Ducky's Dad]

I have been running a pair of 34s in my old GMC for about 18 years with no issues, but I have an isolator in the system. Simple solution is to wire the two batteries with a rotary switch (Blue Sea Systems or similar) so that you can isolate the batteries. You just need to remember to keep the second battery charged. If you don't isolate, then you have lots of capacity but no redundancy. That truck started with an Optima Red as primary and a Yellow for backup, but it has been a pair of Yellows for most of its life.

 

[Herbie]

Man I'm glad I found this thread. I've been trying to decide between two group 34s or one 31. I had no idea 31s were so difficult to maintain. I can't imagine I would be happy with a $400 battery that I was required to plug in on a regular basis just to maintain. Back to leaning towards the 34s again...

Anyone just wired two 34s in parallel for higher capacity but reduced maintenance?? I'm not sure if an isolator is required for my needs.

Minor correction just so you don't cause yourself more grief than needed: Group 34 or Group 31 is just a size category for batteries. Like "AA" or "D". What we're talking about in this thread is the particulars of construction chemistry and details from different companies, since each creates different use/maintenance issues.

If a Group 31-sized battery fits better in your rig, then you should go that route, but do your shopping based on finding the right Group 31 for your needs. The Odyssey/Die-Hard Platinum style battery may not be for everyone, and these are available in multiple sizes (Group 34 included). There are plenty of other Group31 size batteries in a variety of construction types. EastPenn/Deka make a different style Deep Cycle Group31 AGM. There are also plenty of Wet-Cell Group 31s.

Group 34 vs 31 should be about fit and capacity only.

 

[JCDriller]

Thanks for the clarification. I had pretty much decided on odyssey due to their performance. I already have a lithium jump pack so I started thanking that if I'm not concerned with needing a dedicated starting battery I would have more usable amperage with an odyssey g31 instead of 2 odyssey group 34s that only had one for a house battery and I could eliminate the expense and complexity of an isolator. I may get best of both worlds with 2 odyssey 34s in parallel with or without a isolator (again jump pack if my battery is too low to start).

My question is, if I'm unable to isolate the batteries will charging 2 odyssey g34s at a time out too much strain on the alternator (jku 160a) This thought pushes me back to a blue sea ACR install being a must.

 

[BigSwede]

Heh, your alternator is twice as big as my 75a. Hope my Sears Plat 31 will survive. So far so good.

If I were to go dual battery I think I would go Optima red top for starting and yellow top for house battery, with a Blue Sea Add-a-Battery isolator kit...the Optimas are almost $200 less than a pair of Odysseys, although as discussed they are a bit lower in capacity due to their spiral cell design (55 ah (yt) vs. 68 ah for the Odyssey 34). There are also some nice mounts available out there for a pair of Optima 34s.

 

[BigSwede]

My question is, if I'm unable to isolate the batteries will charging 2 odyssey g34s at a time out too much strain on the alternator (jku 160a) This thought pushes me back to a blue sea ACR install being a must.

The Blue Sea ACR will connect the batteries when a charge is present, so that won't save your alternator...if needed, which I doubt.

 

[Hilldweller]

We hit Doug's battery with a couple of different amperages and it still drops voltage immediately.
He's buggered it...

Heh, your alternator is twice as big as my 75a. Hope my Sears Plat 31 will survive. So far so good.

If I were to go dual battery I think I would go Optima red top for starting and yellow top for house battery, with a Blue Sea Add-a-Battery isolator kit...the Optimas are almost $200 less than a pair of Odysseys, although as discussed they are a bit lower in capacity due to their spiral cell design (55 ah (yt) vs. 68 ah for the Odyssey 34). There are also some nice mounts available out there for a pair of Optima 34s.

They recharge so much faster and are so much easier to live with.
In the end, it's easier to get a battery that gets along with your charging system than it is to get a charging system that gets along with your battery(ies)....

I seem to recall that Optima used to advocate using a 100 amp charger to "wake up" a supposedly defunct Optima battery...now they say you should use one of their ($200) chargers.

Go to their youtube site. They have plenty of how-to videos that show how to use common chargers on flat batteries.
A parallel charge is easy and effective.

This is Jim, a member of our forum and all-around nice guy

If you ever have a specific Optima question, send him a PM. He's on the road often but will get to you eventually.