Odyssey vs. Diehard Platinum

[remote camper]

i'll tell you this...

my plat DH doesnt like sitting a vehicle for about year without being used/charged/maintained...

lol...

went to a autozone platinum that is an AGM design also...

That's why it's important to download and carefully review that technical information from Odyssey before buying them. It will likely be applicable to any AGM battery, especially with TPPL technology. Your new one won't like sitting around either.

An AGM has a very low self discharge rate. It should easily have made 1 year without being charged if there were NO parasitic loads and fully charged when it was parked. There is a calculation for parasitic losses in the material that allows you to determine how long you should let it sit for your battery model's amp/hour capacity before it needs recharging (that would mean with an approved charger). Parasitic losses (usually from keep alive memory of on board electronics) MUST be offset. Alternatively, disconnect the negative battery terminal for longer term storage.

At any rate, there's a good chance the Diehard Plat could have been recoverable in a few cycles with a charger that meets the 40% x 10 hour amp hour rating and some time on a desulfator. If the vehicle is not going to be driven, get one of the Odyssey approved chargers that will float at 13.6 volts. Proper charging is the key to a long lived AGM...no matter who makes it. It's always best to follow the battery mfr's recommendations. In my quest, I ran into a surprising # of retailers who really knew nothing about AGM care or gave bad information. Get the tech info your battery from the mfr and be sure to follow it to the letter. From what I have learned, I would stay away from ANY AGM where the mfr could not provide detailed written technical information/charging profile.

 

[rebar]

My 2008 Diehard Platinum P2 is showing its age, 12.2v and I plan on buying two new ones next time sears has it's friends and family sale. What I'm wondering, is why does the odyssey PC1750 require so many amps for a deep cycle charge? I was thinking about using the second Diehard Platinum on my TT which would see deep cycle's unlike the Van.

If I did, I would need to buy minimum, the 25 amp OMAX-25A-1B for deep cycles. And odyssey's larger batteries require 50 amps? wow. Id have to put some penny's under the fuse's for that charger.

My 8 amp batteryminder charger is only approved for my smaller PC310 and PC680's But not for the larger odyssey's Do any lead acid group 65's compare to the Diehard Platinum P2 or PC1750?

 

[remote camper]

Rebar- I just spent an hour replying to your post, but I took too long and "timed out" losing everything I wrote. I will reconstruct it and post again asap.

 

[spressomon]

There's discussion on the web about the Odyssey chargers not being 'all that'; they don't mfg them AFAIK. FWIW I've been using a dual lead Battery Tender in the garage, in between long start-up/run sessions for the rig, on my dual Odysseys for over 5-years with perfect results.

Also per friends...take a look at CTEK smart chargers: http://smartercharger.com/

 

[cruiseroutfit]

The CTEK has been the saving grace for my long-term parked batteries, be it Odyssey, Optima, etc. I used the 'restore' function to bring a ~8 year old Optima back to life and it is holding a charge nicely after a month. I need to run the cycle on the Odyssey's that came out of my Tacoma after ~4 years. They slowly lost their capacity, they worked fine if you drove the truck every few days but parked for a week and the low voltage alarm was firing. They had a hard life so I was fine replacing them with a new pair but I think with the CTEK it might be able to salvage them?

 

[Hilldweller]

The CTEK has been the saving grace for my long-term parked batteries, be it Odyssey, Optima, etc. I used the 'restore' function to bring a ~8 year old Optima back to life and it is holding a charge nicely after a month. I need to run the cycle on the Odyssey's that came out of my Tacoma after ~4 years. They slowly lost their capacity, they worked fine if you drove the truck every few days but parked for a week and the low voltage alarm was firing. They had a hard life so I was fine replacing them with a new pair but I think with the CTEK it might be able to salvage them?

That's a good charger, Kurt.

I have an Optima charger and it will do essentially the same thing; most chargers won't "see" a deeply discharged battery and won't even start the charge cycle --- although you think it's charging.

Another method of recovering a deeply discharged AGM battery (that isn't overly sulfated or otherwise abused) is to wire it in parallel to another healthy/charged AGM battery and charge the pair together for about 2 hours. Hopefully the discharged battery is over the threshold that the charger can "see" by now, remove the good battery and continue to charge the formerly discharged one to full charge.
This would be at about 10 amps with a charger designed for AGM batteries of course.

 

[remote camper]

My 2008 Diehard Platinum P2 is showing its age, 12.2v and I plan on buying two new ones next time sears has it's friends and family sale. What I'm wondering, is why does the odyssey PC1750 require so many amps for a deep cycle charge? I was thinking about using the second Diehard Platinum on my TT which would see deep cycle's unlike the Van.

If I did, I would need to buy minimum, the 25 amp OMAX-25A-1B for deep cycles. And odyssey's larger batteries require 50 amps? wow. Id have to put some penny's under the fuse's for that charger.

My 8 amp batteryminder charger is only approved for my smaller PC310 and PC680's But not for the larger odyssey's Do any lead acid group 65's compare to the Diehard Platinum P2 or PC1750?

Based on my discussion with Odyssey last year, it shakes out like this:

For most automatic chargers, the bulk and absorption stages are timed. For the amount of time an 8 amp charger remains in the bulk stage, it can't supply enough amp hours to raise a deeply discharged battery voltage to 14.7 volts. The 25 amp charger can get the amp hours restored in its timed bulk stage, raising battery voltage to 14.7 volts and then transition to the absorption stage, continuing to supply a tapering down charge current at a constant voltage of 14.7 volts. Once charge current tapers to 50-100 ma, it transitions to float @ 13.6 volts. For a charger to be approved by Odyssey, it must be able to meet that charge profile. It should also be temperature compensated.

If your 8 amp charger is a "smart charger", it might just "time out" in the bulk stage. If that happens, you might be able to simply disconnect and reconnect which will restart it where it left off (still in the bulk stage). You might have to do this a number of times in order for the charger to bring the battery to 14.7 volts. This should work as the amp hours returned to the battery are cumulative. Unless you apply a load, the amp hours you put back are still there. I am assuming the charging profile for your charger provides for a 14.7 volt transition because it's approved for the lesser amp hour Odyssey batteries.

A dumber charger, like the Heart Interface Freedom 458 I describe below will just go through its normal 3 stage routine, oblivious to the needs of our P2s.

Disconnecting and reconnecting a lesser charger many times is inefficient. Also, the engineer I spoke with stated that for the Odyssey battery chemistry to be conditioned optimally, it needs the in-rush of high current in the bulk stage the OMAX-25A-1B can provide. I call it the "fire hose" stage.

Regular 3 stage battery chargers are inadequate usually for 2 reasons. They either can't supply the amount of current in the allotted time for the bulk/absorption stages or they transition to float too early, usually at 14.3 or 14.4 volts. Our AGMs and the Optimas, need to be brought to 14.7 volts to transition to absorption and remain at 14.7 volts for the rest of the absorption stage. If they are deep cycled and never see 14.7 volts, battery life can be shortened as much as 25%.

Such is the case with a Heart Interface Freedom 458 I have. It can supply the current, but even in its AGM setting, it transitions to absorption at 14.4 volts. This is inadequate for maximum life from an Odyssey battery, even the lesser amp hour ones!!! You can't trust what a mfr says about a charger being suitable for AGMs unless you know your specific AGM's charging profile and the the profile of the charger!

I haven't deep cycled my P2s yet and have had them since September 2012 (9 mos). Currently, I have a 2012-AGM that can supply only 2 amps. It can get through bulk, absorption and into the float stage with no issues and in very short order, even with the batteries in parallel and the parasitic load of the on board electronics of my truck. When voltage drops to 12.6 volts after a period of not being driven, I put the 2012-AGM on it and let it go through all 3 stages and float/desulfate for a couple of days. For deep cycling though, the 2012-AGM would be woefully inadequate.

I do plan to deep cycle the P2s. When I do, am going to use the 458 for the inrush of current. When it reaches it transition of 14.4 volts, will put the 2012-AGM on it so it's bulk stage can bring the battery to 14.7 volts. If it times out, will disconnect/reconnect to restart it in the bulk stage until it can get the battery voltage up. The 14.4 is a little short, but the amount of amp hours restored by that time would likely be no different than a modestly discharged battery. The 2012 might need to work a little harder, but from there, it should be able to finish the bulk stage and continue on through the 14.7 volt absorption stage and into float.

We might be able to get away with the disconnect/reconnect method for occasional deep discharges, but for regular deep cycle operation we'll be better off with a more substantial charger designed for our type AGM. It doesn't have to be an OMAX-25A-1B. It just has to have the proper charging profile and supply the amps needed for our capacity battery for deep cycle operation.

One of the publications at the link in my original post describes how to charge our batteries with a manual charger. What I described above is just an extension of that using the chargers we have available. Also note that all voltage measurement must be made at the battery. Some chargers have detachable cables. If the wrong gauge cables are substituted or there are poor connections, you can lose as much as .3 volts at the battery. The bulk transition to absorption would be correct at the charger terminals, but would be .3 volts lower at the battery. Same with float. The lower voltages over the long term will result in an under charged battery and shortened battery life.

Will look at your question again to see if I missed anything. Hope this helps, so far.

 

[remote camper]

One more note on Odyssey approved chargers. In addition to the charging profile needed for the size battery, I believe they have to have desulfation capability. It looks like they update the list occasionally, so check back.

 

[dwh]

Based on my discussion with Odyssey last year, it shakes out like this:

For most automatic chargers, the bulk and absorption stages are timed.

Actually, for most there is no timer at all. They just constant current bulk to the set point, and then switch to constant voltage and hold at the absorb set point until the amp flow drops below a preset limit - generally between 1a and 3a depending on who made the charger.

There are a few with timers, and a few with timers only on the absorb stage, and of course a programmable can do whatever it's programmed to do.

There are chargers with timers on both bulk and absorb (for instance any Iota that has the IQ/4 control module added), but most don't have timers.

You can't trust what a mfr says about a charger being suitable for AGMs unless you know your specific AGM's charging profile and the the profile of the charger!

Since most AGMs specify the same 14.4v bulk / 14.2v absorb / 13.(something) for float...in most cases a battery charger that has an AGM setting is just doing exactly the same profile it would do in the "flooded" setting. Which is fine, since that's what most AGMs want anyway.

Odysseys and Optimas are oddballs and specify oddball charge profiles, though Optima also says:

"Can you trickle-charge an OPTIMA® battery? And what type of charger can I use?
Yes, and you can use any charger on an OPTIMA Battery as long as the voltage is regulated properly. If your charger will remain on indefinitely, the voltage should be at 13.8 volts maximum with a one-amp maximum current."

http://www.optimabatteries.com/us/en/support/faqs/


And good luck finding a non-programmable solar charge controller that's preset to 14.7v bulk and 14.7v absorb.

If the wrong gauge cables are substituted or there are poor connections, you can lose as much as .3 volts at the battery. The bulk transition to absorption would be correct at the charger terminals, but would be .3 volts lower at the battery.

Not exactly. It's a loop - the voltage at the battery will be the same at any other point on the loop...even at the charger. Though, bad or inadequate cables will cause a voltage drop...over the entire loop.

Same with float. The lower voltages over the long term will result in an under charged battery and shortened battery life.

Not true. Voltage drop is a function of load. By the time the charger reaches float, the amp flow won't be much - a couple of amps, tops - and the voltage drop will have disappeared.

 

[WorldTraveler]

INTERSTATE MT-7 AGM

I just bought this Interstate MT-7 Battery that came out a few months ago to replace my Yellow Top Optima (Garbage IMO). It's supposed to be Interstates version of the Odyssey, but even better. Not sure about all of the Battery Terminology, but the guy at Interstate made it sound good. It comes with a 4-Year Free Replacement Warranty. Very happy with it so far. Need to buy another one!

 

[dwh]

Yea...Interstate. If you have the manual for the MT-7, I'd appreciate if you could post the charge specs/profile from the manual.


From their FAQ page:

http://interstatedealers.com/ChargersFAQs.asp

"Do I need a special charger for recharging sealed AGM batteries?

Yes, when recharging sealed lead-acid AGM or Gel-type batteries it is best to choose a charger with a selection specifically for them. These batteries can be overcharged by some chargers that are used for regular or liquid electrolyte batteries. Some of the liquid electrolyte chargers have their internal voltage regulation set too high for AGM or Gel battery."


So what they are saying there (by lumping AGM and Gel together, which is just dumb), is that it's bad to overcharge SEALED batteries. Well...duh.

It's crap like that just adds to the confusion, as it makes it appear that AGM is some special beast that requires a special charger.


Notice on that same FAQ page - in regards to charging, they lump their AGM in with the conventional flooded (which is fine, since most AGMs take the same charge profile as most flooded):

"Powersport:
Conventional Flooded Batteries and AGM/Sealed Valve Regulated Batteries:

Determine the state-of-charge with a voltmeter. Valve-regulated batteries are fully charged at approximately 12.80-13.00 volts after sitting for 1-2 hours in a static condition (no loads or charging).

Batteries with voltage between 12.50–12.80 may need a slight charge. These batteries are below a 75% state-of-charge and a maintenance charge will keep the plate material fresh and prevent sulfation.

Batteries with voltage less than 12.50 should be recharged at the recommended rates. Charge time for these batteries will range from 5-13 hours.

Batteries below 11.50 volts require longer recharge times (20 hours) and often require special charging techniques. Voltage readings this low are often an indication of internal damage and usually requires replacement. At the very least, these batteries have very high internal resistance and can require higher voltage and special equipment to overcome the high resistance. Use care when attempting to recharge low-voltage batteries. Batteries that gas heavily and emit a strong odor are most likely damaged.

Select a charger that is approximately 1/10th the amp hour capacity of the battery. The proper charger levels can normally be found on the battery label. Use a charger designed for motorcycle/powersport batteries. Constant current or manual chargers are not recommended."


My search-**** is pretty good, but it's difficult to find specific charge profiles for Interstate batteries - partly because their web site is a piece of crap where they don't stick to any standard nomenclature...half the time there are hyphens in the product names/numbrers and half the time there are spaces.

Here is a .pdf for an Interstate 35ah deep cycle AGM which lists the max charging current as less than or equal to 14a (just about C/2, but that's max, not "recommended"...they typically recommend C/10) and the max charge/eq voltage as 14.5v-14.9v - which is in the ballpark for any lead-acid battery except Gel type and which Odyssey's 14.7v recommended is in the sweet spot right in the middle of that range.

"Equalization and Cycle Service
Charging and Current Limits
≤ 14 A, 14.5 - 14.9 volts"

http://www.interstatebatteries.com/cs_estore/content/product_info/specs/dcm0035.pdf


Here's the charge specs for something called the UAGM8D, which I would assume is an 8d size AGM battery - but I can't find the bloody thing on their web site:


"Charging recommendation for the UAGM8D (rated at 250 AH at the 20-hour rate):

Voltage of the Battery System - 12
Charging Current - C/10
Bulk Charge Voltage - 14.4v
Absorption Voltage - 14.4v
Absorption Time in Hours - 2 to 4
Float Voltage - 13.2
Equalization Voltage - 14.4v
Equalization Time in Hours - 2"

http://www.batteries-faq.com/activekb/questions.php?questionid=1

Note that that battery has a 250ah capacity (well, yea...it's an 8D size) and they recommend a C/10 charge rate.

 

[Hilldweller]

Pity about the Interstate website; I've used literally hundreds of their batteries and always had great results with them.

 

[dwh]

Pity about the Interstate website; I've used literally hundreds of their batteries and always had great results with them.

Um...if you had such great results...why did you need so many?





(I better add that I'm just kidding and not knocking Interstate, before someone gets excited. I've had a few and they worked just as well as any others.)

 

[teotwaki]

Um...if you had such great results...why did you need so many?





(I better add that I'm just kidding and not knocking Interstate, before someone gets excited. I've had a few and they worked just as well as any others.)

He is a rich Hillbilly with lots of old cars strewn about the family farm? LOL :sombrero:

 

[Xterabl]

Probably owns or operates a golf course...
Plenty of those down in GA.