DieHard Platinum 31M DEAD

[80t0ylc]

I'm guessing the DHP marine and auto batteries are the same internally. It's just a matter of which size is marketed to which group. Group 31 is mostly used as a marine and commercial type battery but can be used at an auto battery. If you look at Odyssey website and click on the different categories: Marine, HD/Commerical, and Auto, only certain batteries will appear. But their group 31 sizes shows up in all three of those categories.

http://www.odysseybattery.com/batteries.html

And like PPC said, the marine environment is harsher than automotive and hence the different in DHP warranty. 3 vs 4 years.

Yeah, well I disagree with the idea that the marine environment is harsher. It's apples & oranges, but I do think that current design of each type is stout enough to hold up in either environment - at least for a while. And while one owner gets 6 months life and another gets 6 years out of the same brand and model is curious. A lot of variables to consider.

Last weekend I picked up a 34/78 DHP to replace my 5+ yr old Costco deep cycle aux battery in my '94 80 series. It had trouble supplying my 50L fridge/freezer with good power over night this past summer. I have an isolator installed in my setup and the primary battery is a Wal-mart that has been trouble free for 5+ years now. I haven't installed the DHP yet and now I'm reconsidering using it as the primary instead, considering the age of both batts. I've got a 6 mo. old top of the line RV battery in excellent shape that will just sit idle most of the winter that I can use for the secondary. After reading through this thread, I think the DHP will work in either spot fine.

 

[hoser]

Yeah, well I disagree with the idea that the marine environment is harsher. It's apples & oranges...

I'm curious to hear your thoughts on that. Auto batteries are subjected to more extreme temperatures but vibration is generally greater in Marine application. I think the largest impact on battery life is how often and deep they are cycled. When most people are in a car, the engine running and there is little draw on the battery. When most people are in boats, the engine might be running half the time. A battery that is discharged to 90% capacity everyday is going to last a lot longer than one that is discharged to 70% capacity everyday.

 

[PDoyle]

Anyone else have the negative terminal hitting the hood when it is closed? That would explain alot.

 

[ChaseTruck]

Anyone else have the negative terminal hitting the hood when it is closed? That would explain alot.

What would that explain? Physical transmission of vibrations from the body into the battery through the direct contact?

The hood, for all intents and purposes, is ground, right?

 

[Funner]

What would that explain? Physical transmission of vibrations from the body into the battery through the direct contact?

The hood, for all intents and purposes, is ground, right?

IDK, maybe every time you close the hood you are slamming the negative terminal and that too causes damage? The grounding logic is unassailable.

 

[mattafact]

I haven't noticed mine hitting the hood.

 

[livinoffroad]

One thing to remember: if a new batt is connected to an old batt...the old batt will "draw down" the new batt to the same condition of the old batt, so use your isolation switches whenever possible, if the batts are different condition. If you run 2 batts, install 2 new ones at the same time.

AGM's like a lower range of charge voltage than wet cells, and benefit from pulse charging (PWM or pulse width modulation) to de-sulphate. Knowing this, I've cycled my DHP grp 65 on the AGM smart charger regularly, since installing it, cuz like some of you have said...once they sulphate too deeply, you can't recover them.

BTW...bought the DHP grp 65 on 4/15/2009, sat on the shelf until installation on 2/8/2010, and no issues after 36K miles of service.

What I'd like to do, if it's possible, is to adjust the voltage output of the regulator, which is inside the alternator.

I have not had the alt open so, any of you had any luck with voltage adjustments for AGM batts??

 

[thadscottmoore]

I run dual Odyssey batteries with hell roaring isolator switch in my ride and have had them for a few years now with no issues- besides wife or son leaving the headlights on and forgetting to turn them off and running 1 battery completely down a few times- AGM battery charger restores downed battery in no time. I know that my battereries manufacturer (EnerSys Energy Products Inc) is the manufacturer for Sears Diehard batteries- just surprises me to hear people having issues like that. Of course, my batteries are the smaller 1200MJTs sitting side by side in single battery tray. and there isnt a diehard made in that size...

 

[SanDiegoCruiser]

My Diehard 31 series failed after 1.5 years. I took it back and got a new one free. After seeing all of these failures, it makes me wonder if there is something about our alternators and deep cycle batteries. I'm running dual batteries like others in this thread.

I wonder if a battery tender was used once a week over night if that would be enough to prevent these failures?

 

[80t0ylc]

I'm curious to hear your thoughts on that......

You describe it well, below \/

.........Auto batteries are subjected to more extreme temperatures but vibration is generally greater in Marine application. I think the largest impact on battery life is how often and deep they are cycled. When most people are in a car, the engine running and there is little draw on the battery. When most people are in boats, the engine might be running half the time.......

You're right on, but you didn't go far enough. The biggest contributor to an automobile battery death is it has been "deep cycled" too many times, for whatever reason. Lights or other accessories left on without engine running; poor tuning causing too much cranking; worn out alternator or other charging system fault. Suddenly it won't start or crank so we throw it on a battery charger and it's good for a while, but only a few times. Then all of a sudden it won't hold a charge any more and down to the store we go for a new battery.

....... A battery that is discharged to 90% capacity everyday is going to last a lot longer than one that is discharged to 70% capacity everyday.

A deep cycle is designed to be "deep" discharged, so while this may be true for the standard auto battery, it really doesn't apply to the deep cycle or marine batteries. While a deep cycle survives being run down and charged back up much better than an auto battery, it doesn't hold up as well as the auto batt when subjected to long 'high amp draws' such as winch pulls or having to crank an engine excessively. The newer multi purpose batteries are supposed to be better - plate design and material they're made out of.

 

[80t0ylc]

Anyone else have the negative terminal hitting the hood when it is closed? That would explain alot.

Not sure if you read my post (#29), but the 31M is almost 2" taller than the proper sized DHP (34/78DT) for an 80 series. If you're going to run a bigger battery, you really need to modify your battery tray or sawzall your hood. IMO either post of the batt should not be touched by anything but the connections. And there should be some clearance to allow for flex and vibration of vehicle operation.

 

[hoser]

A deep cycle is designed to be "deep" discharged, so while this may be true for the standard auto battery, it really doesn't apply to the deep cycle or marine batteries. While a deep cycle survives being run down and charged back up much better than an auto battery, it doesn't hold up as well as the auto batt when subjected to long 'high amp draws' such as winch pulls or having to crank an engine excessively. The newer multi purpose batteries are supposed to be better - plate design and material they're made out of.

Uh, I thought we were only talking about the DHP/Odyssey multipurpose batteries here... and how the exact same battery will have a different warranty/life expectancy when used in a marine vs auto environment.

 

[alia176]

I've had the DieHard 31M for a few months. I have not had any issues.

The sales guy at Sears did tell me they won't hold up with a automotive charging system. He claims they charge the battery to fast.

I have the 100 connected to the small post via adapter, and a 12K winch on the main terminal. So far so good, everybody that I talk to with 31M's (Diehard) say they don't last. My original Toyota battery lasted until 2008. I installed a Duralast Gold (can't remember the model) and beat the living s*** out of it. I can't remember how many times I killed that battery, leaving lights on, tailgating all night. It probably had 50+ jump starts on it and several short outs (tools grounding out while tightening it). It wasn't until I installed the winch and did a really hard pull, I think I may of melted something inside of it. I then drove with a dead battery (7.4V) for a few weeks, it's now my 2nd battery and still kicking ass . I hope the DieHard, dies hard.

I believe the highlighted section is spot on; these batts don't like being charged too quickly in a vehicle. They behave like a true deep cycle batts and not the starting/deep cycle type, similar to the Optimas or other batts. They want to trickle charged slowly. That'll explain how we're killing these batts in short order

 

[80t0ylc]

Anyone else have the negative terminal hitting the hood when it is closed? That would explain alot.

IIRC, this is one reason why this thread was started.

Uh, I thought we were only talking about the DHP/Odyssey multipurpose batteries here... and how the exact same battery will have a different warranty/life expectancy when used in a marine vs auto environment.

What's your point? Mine is: I'm still unconvinced that the multi purpose is much of an improvement. But, I'll be giving the 34/78/DT DHP a try as a starting batt in my 80.

I believe the highlighted section is spot on; these batts don't like being charged too quickly in a vehicle. They behave like a true deep cycle batts and not the starting/deep cycle type, similar to the Optimas or other batts. They want to trickle charged slowly. That'll explain how we're killing these batts in short order

That's good info I wasn't aware of. Thanks for posting!

So, not only does the OP have a fitment problem, but he'll be having longevity problems also. The 31M sounds like a poor choice for a low maintenance battery for an 80 series - or for any landlubber rig for that matter

 

[NLXTACY]

I run dual Odyssey batteries with hell roaring isolator switch in my ride and have had them for a few years now with no issues- besides wife or son leaving the headlights on and forgetting to turn them off and running 1 battery completely down a few times- AGM battery charger restores downed battery in no time. I know that my battereries manufacturer (EnerSys Energy Products Inc) is the manufacturer for Sears Diehard batteries- just surprises me to hear people having issues like that. Of course, my batteries are the smaller 1200MJTs sitting side by side in single battery tray. and there isnt a diehard made in that size...

This is me. Two platinum batteries with a Hellroaring isolator. I do not use the combining function to keep everything separate. I have everything auxiliary running off the aux battery. I've been moving non critical devices over to aux as well, such as the radio. My main does one thing, start the truck. I have tons of electrical devices and fuse panels and switches and crap installed and it's about to get worse

But no issues since I did this in 2008. Until my aux died. Went to sears and replaced it. It was out of warranty but so what? 5 years and never a problem. My truck starts every time. Of course let's throw out a caveat, this truck is driven every single day and I've never once put on an external charger including solar.

 

[hoser]

What's your point? Mine is: I'm still unconvinced that the multi purpose is much of an improvement. But, I'll be giving the 34/78/DT DHP a try as a starting batt in my 80.

My point is DHP platinum is same battery internally for use with both autos and marine (though labeled differently). But when used for Marine, the expected life is less than when used for an auto. This is shown by their warranty. Odyssey, on the other hand, will give the same battery the same warranty for either auto or marine use but it is only 3 years (vs 3-4 years on a DHP).

Let me recap below:

I'm guessing the DHP marine and auto batteries are the same internally... If you look at Odyssey website and click on the different categories: Marine, HD/Commerical, and Auto, only certain batteries will appear. But their group 31 sizes shows up in all three of those categories.

http://www.odysseybattery.com/batteries.html

And like PPC said, the marine environment is harsher than automotive and hence the different in DHP warranty. 3 vs 4 years.

Yeah, well I disagree with the idea that the marine environment is harsher.

... I think the largest impact on battery life is how often and deep they are cycled. When most people are in a car, the engine running and there is little draw on the battery. When most people are in boats, the engine might be running half the time. A battery that is discharged to 90% capacity everyday is going to last a lot longer than one that is discharged to 70% capacity everyday.

... A deep cycle is designed to be "deep" discharged, so while this may be true for the standard auto battery, it really doesn't apply to the deep cycle or marine batteries. While a deep cycle survives being run down and charged back up much better than an auto battery, it doesn't hold up as well as the auto batt when subjected to long 'high amp draws' such as winch pulls or having to crank an engine excessively. The newer multi purpose batteries are supposed to be better - plate design and material they're made out of.

Uh, I thought we were only talking about the DHP/Odyssey multipurpose batteries here... and how the exact same battery will have a different warranty/life expectancy when used in a marine vs auto environment.

 

[Roc Doc]

If you run a battery down to below 10v, some chargers won't kick on, so the way around it is to use a second fully charged battery in parallel and then the charger will see a higher voltage and begin charging the dead battery.

From the Optima site;

If an OPTIMA battery is deeply discharged (below 10.5 volts), most basic chargers will not supply a charge. Also keep in mind that an OPTIMA battery will not recharge properly if treated as a regular flooded or gel battery. To charge the battery, you can wire a second fully charged automotive battery (12+volts) to the discharged AGM in parallel (+ to + and – to –). Then hook up the charger to the deeply discharged battery, setting the charger at 10 amps. Leave for two hours, monitoring frequently. During this process, if the discharged battery gets very hot or if it is venting (hissing sound from vents), then stop this process immediately. When the discharged battery reaches 10.5 volts or more, remove the standard battery and continue charging the AGM until fully charged.

For normal charging, a relatively low current, such as one or two amps, can work well, but when the battery has been deeply discharged, some sulfation of the battery plates may have occurred. If you charge at 10 amps, the higher current will help to break up this sulfation.

If you have an automatic charger, let it run until the charger indicates charging is complete. If you have a manual charger, you can get a rough estimate of the charging time in hours of a completely discharged battery (11.2 volts) by multiplying the capacity (amp hours or Ah) of the battery by 1.2. If your battery is not completely discharged, the time would be less.

In most cases these steps will recover an AGM battery. It’s OK for the AGM battery to get slightly warm during the charging process. If it’s hot to the touch, it means there’s a short and the process should be discontinued.

 

[80t0ylc]

My point is DHP platinum is same battery internally for use with both autos and marine (though labeled differently). But when used for Marine, the expected life is less than when used for an auto. This is shown by their warranty. Odyssey, on the other hand, will give the same battery the same warranty for either auto or marine use but it is only 3 years (vs 3-4 years on a DHP)............

If you're basing your point on website info, I think you're in error. Your not going to get the info you need from a website unless it's tech support with an answer to the specific question: Is internal design the same? I understand your pessimistic belief that they are, but I can't accept it. Especially considering remarks made by Sears employees to 31M owners mentioned earlier in this thread regarding automotive charge systems charging the marine batts too quickly. Why don't we hear the same thing for the automotive DHP batts? With a 4 year warranty they'd be out of the battery business having to replace all the defects and you'd think it'd be common knowledge by now with all the consumer watchdogs.

 

[Roc Doc]

One of the best features of an AGM is its low internal resistance, and thus it's ability to take a high amp charge, no matter if it's designated Marine or Automotive. A lead acid battery will boil it's electrolyte off if you try to do the same thing.

 

[alia176]

One of the best features of an AGM is its low internal resistance, and thus it's ability to take a high amp charge, no matter if it's designated Marine or Automotive. A lead acid battery will boil it's electrolyte off if you try to do the same thing.

One thing to note about AGM batts is that they don't like being charged with the older battery chargers, can't recall why that is exactly. Seems that the newer solid state chargers with built in CPUs are what we're suppose to use these days.

Back to your regularly scheduled debate......let's keep it clean and informative please