Duracell Platinum AGM vs Ultra Platinum AGM

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I purchased a Duracell Platinum AGM 24F from Sam’s Club last night. 36 month free replacement warranty, 710 CCA for $172.13.

Batteries Plus carries a Duracell Ultra Platinum AGM with the same CCA spec but with a 48 mo free replacement.


I assume the only difference between the two models is the warranty?
 

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The longer the warranty the higher the plates sit in the case. As the battery ages plate material sloughs off and accumulates on the bottom of the case, at some point it reaches the plate level and can weaken or even short the cells. At least that is my understanding of how it works.
I would guess the quality of the materials may also play a roll.
 
The longer the warranty the higher the plates sit in the case. As the battery ages plate material sloughs off and accumulates on the bottom of the case, at some point it reaches the plate level and can weaken or even short the cells. At least that is my understanding of how it works.
I would guess the quality of the materials may also play a roll.
Does that happen with AGM?
 
Compare the weight of the two batteries. If they are the same, one is likely just paying extra for the warranty.

Return them to high states of charge promptly after discharge, and keep them there, and its highly unlikely one would ever need to exercise any warranty.

AGMS really like the true 100% recharge, and arguably need it more so than flooded, but especially when cycled deeper, intentionally or not, like when sitting for extended periods with larger parasitic draws on them.

Expecting the vehicle's charging system to return a battery to top charge quickly, and keep it there, is not wise.
 
Compare the weight of the two batteries. If they are the same, one is likely just paying extra for the warranty.

Return them to high states of charge promptly after discharge, and keep them there, and its highly unlikely one would ever need to exercise any warranty.

AGMS really like the true 100% recharge, and arguably need it more so than flooded, but especially when cycled deeper, intentionally or not, like when sitting for extended periods with larger parasitic draws on them.

Expecting the vehicle's charging system to return a battery to top charge quickly, and keep it there, is not wise.
With the ECM controlling the charging in most vehicles these days it should be sophisticated enough to charge the battery properly. Assuming your trips are not all short trips. Maybe that only happens if the vehicle requires an AGM or if you update the vehicle software settings to say the battery is an AGM.
 
Does that happen with AGM?
As I understand it AGM is still a lead acid battery and will suffer from plate deterioration over time, they may tweak the location of the mats but the accumulated deposits have to settle somewhere. May be someone that has manufacturing experience with them can chime in.
 
With the ECM controlling the charging in most vehicles these days it should be sophisticated enough to charge the battery properly. Assuming your trips are not all short trips. Maybe that only happens if the vehicle requires an AGM or if you update the vehicle software settings to say the battery is an AGM.
Fully charging a battery is about voltage control, and the duration of higher voltages allowed by the voltage regulator, wherever it might be located in teh vehicle.

The ideal of a fully charged battery, is an ever moving goalpost which changes with battery state of charge, age and condition and temperature and the position of the nearest locust

ECU control of voltage is not about quickly and fully charging batteries, it is about fuel economy, and never overcharging. Each 25amps an alternator makes takes up one engine HP, as alternators are only ~55% efficient.

People here love to assume one battery is better than another by the sticker on it, and that the only variable affecting battery longevity is the heat it is subjected to, and who made it, or put a sticker on it.

But it is the average state of charge of the battery which has, by far, the largest effect on the longevity of the battery.
Assuming the vehicle's charging system always has the best interest of the battery in mind, is unwise in the extreme.

My Dad owns a 2014 stingray.
The battery is AGM, group 49, and is now 2 years old, I forget the brand/Sticker/reseller.
The vehicle sits a lot. It just barely started when my dad and I took it out. It had been sitting unused for no less than 3 weeks.
When It was my turn to drive I bounced it off the rev limiter several times, we had it out for over an hour and what A joy it is to run it through those first three gears right foot mashed to the floor after letting out the clutch..

When we returned my dad declared the battery had to be fully charged. He was the engineer in his younger years. Has to be right, even when he is not.
I hook up my clamps to battery terminals, and ask him what he thinks the voltage is going to be, after our hour long Sunday drive.
12.7 he declares. I though that surface charge would still have it up at 13.1 or higher.
It read 12.23v.
I hook up my 40 amp adjustable voltage adjustable voltage power supply that I had set to 14.7v before hooking it to the wattmeter.
40 amps flowed for about 3 minutes before voltage rose to 14.7v, and amps begun tapering.

So much for the corvette's charging system quickly charging the battery.
6 hours after bringing the battery to 14.7v, it was still accepting 1.6 amps. Still quite a distance from being fully charged.
4 hours after that it had tapered to only 1.2 amps. As I was going to bed, I lowered voltage to 13.6v and amps tapered to 0.5 after 2 minutes, at that point.
14 hours later held at a constant 13.6v, unobserved, amps read 0.0x.
I cranked voltage back upto 14.7v and amps went as high as 2.3, but quickly tapered to under 0.3 and I removed the power supply.

So 10 hours of being held at 14.7v was not enough to fully charge the battery, after it still had barely enough juice to start the engine and was then driven for over an hour. Several more hours held at 13.6 were required, and to my surprise actually did fully charge the battery.

Even if the stingray was holding 14.7v the entire hour long drive the day previous, which it most certainly was NOT, it would still have taken many many hours on a constant voltage 14.7v charger to come anywhere near close to being fully charged.

If you want to know how well your vehicle takes care of the battery, monitor the voltage it allows, not just after engine starting, but the whole time the engine runs. You will likely be very disappointed in the duration at which 14+ volts is allowed.

When you shut it down, remove any surface charge and put a so called smart charger on it, and see how much longer it takes before the green light comes on. Then if you can dip a hydrometer, check specific gravity. One will likely be disappointed.

Assuming the vehicle is taking great care of a battery and the only variable influencing battery longevity is the average temperature, and who made/stickered/marketed the battery, or how long it is warrantied for, is unwise in the extreme, to put it politely.

It is certainly possible for smart voltage regulation to take much better care of a battery, but they don't bother as timid voltage regulation can be employed to eek out 0.002 more MPG and put more profit in pocket of auto executives, at the expense of the owner of the vehicle's battery.
 
Fully charging a battery is about voltage control, and the duration of higher voltages allowed by the voltage regulator, wherever it might be located in teh vehicle.

The ideal of a fully charged battery, is an ever moving goalpost which changes with battery state of charge, age and condition and temperature and the position of the nearest locust

ECU control of voltage is not about quickly and fully charging batteries, it is about fuel economy, and never overcharging. Each 25amps an alternator makes takes up one engine HP, as alternators are only ~55% efficient.

People here love to assume one battery is better than another by the sticker on it, and that the only variable affecting battery longevity is the heat it is subjected to, and who made it, or put a sticker on it.

But it is the average state of charge of the battery which has, by far, the largest effect on the longevity of the battery.
Assuming the vehicle's charging system always has the best interest of the battery in mind, is unwise in the extreme.

My Dad owns a 2014 stingray.
The battery is AGM, group 49, and is now 2 years old, I forget the brand/Sticker/reseller.
The vehicle sits a lot. It just barely started when my dad and I took it out. It had been sitting unused for no less than 3 weeks.
When It was my turn to drive I bounced it off the rev limiter several times, we had it out for over an hour and what A joy it is to run it through those first three gears right foot mashed to the floor after letting out the clutch..

When we returned my dad declared the battery had to be fully charged. He was the engineer in his younger years. Has to be right, even when he is not.
I hook up my clamps to battery terminals, and ask him what he thinks the voltage is going to be, after our hour long Sunday drive.
12.7 he declares. I though that surface charge would still have it up at 13.1 or higher.
It read 12.23v.
I hook up my 40 amp adjustable voltage adjustable voltage power supply that I had set to 14.7v before hooking it to the wattmeter.
40 amps flowed for about 3 minutes before voltage rose to 14.7v, and amps begun tapering.

So much for the corvette's charging system quickly charging the battery.
6 hours after bringing the battery to 14.7v, it was still accepting 1.6 amps. Still quite a distance from being fully charged.
4 hours after that it had tapered to only 1.2 amps. As I was going to bed, I lowered voltage to 13.6v and amps tapered to 0.5 after 2 minutes, at that point.
14 hours later held at a constant 13.6v, unobserved, amps read 0.0x.
I cranked voltage back upto 14.7v and amps went as high as 2.3, but quickly tapered to under 0.3 and I removed the power supply.

So 10 hours of being held at 14.7v was not enough to fully charge the battery, after it still had barely enough juice to start the engine and was then driven for over an hour. Several more hours held at 13.6 were required, and to my surprise actually did fully charge the battery.

Even if the stingray was holding 14.7v the entire hour long drive the day previous, which it most certainly was NOT, it would still have taken many many hours on a constant voltage 14.7v charger to come anywhere near close to being fully charged.

If you want to know how well your vehicle takes care of the battery, monitor the voltage it allows, not just after engine starting, but the whole time the engine runs. You will likely be very disappointed in the duration at which 14+ volts is allowed.

When you shut it down, remove any surface charge and put a so called smart charger on it, and see how much longer it takes before the green light comes on. Then if you can dip a hydrometer, check specific gravity. One will likely be disappointed.

Assuming the vehicle is taking great care of a battery and the only variable influencing battery longevity is the average temperature, and who made/stickered/marketed the battery, or how long it is warrantied for, is unwise in the extreme, to put it politely.

It is certainly possible for smart voltage regulation to take much better care of a battery, but they don't bother as timid voltage regulation can be employed to eek out 0.002 more MPG and put more profit in pocket of auto executives, at the expense of the owner of the vehicle's battery.
But many people like me don't want to be bothered to do some extra charging process weekly or monthly. We want the vehicle to properly charge the battery if we drive the vehicle on a regular basis. And you were charging with a power supply, not a smart charger. Even more complexity to the charging process.
 
I don't want to be messing with battery chargers once a week or once a month even. If the car cant maintain a charge for that long without putting a charger on it there is something wrong with it.
 
I agree.
Better for average joe remain unaware and hope vehicle take good enough care that it lasts an acceptble amount of time.

'Acceptable' being variable, and subjective.



Not very bitog like though.
 
But many people like me don't want to be bothered to do some extra charging process weekly or monthly. We want the vehicle to properly charge the battery if we drive the vehicle on a regular basis. And you were charging with a power supply, not a smart charger. Even more complexity to the charging process.
If you drive your vehicle 2 hours a day for 5 days a week, the charging system will probably keep the battery at an "acceptable" state of charge, without external charging. But it won't be 100% SOC, and the battery will sulfate, and it will lose capacity, especially if the car uses stop/start.

I am surprised that there are apparently no "carbon enhanced" batteries on the market for automotive use (AFAIK). Carbon based additives have been shown to increase charge acceptance and reduce the rate of battery sulfation. The Exide Edge AGM was a carbon enhanced battery, but it went off the market a few years ago.


Enhancing Lead Acid Batteries With Carbon
 
But many people like me don't want to be bothered to do some extra charging process weekly or monthly. We want the vehicle to properly charge the battery if we drive the vehicle on a regular basis. And you were charging with a power supply, not a smart charger. Even more complexity to the charging process.


Donald... Your vehicles are programmed NOT to charge the battery properly.... Mine isn't programmed to do that either.

A legitimate properly charged battery is one that actually gets to 100 percent state of charge.

Almost every vehicle out there built in the last 12-14 years are running around at 80-90 percent SOC. That's all you get from the ECU fuel economy management system built in by the manufacturers.
 
I added a PV panel to the camper shell of my truck 2 years ago. Proof that the truck doesn’t provide a full charge?.... it takes about 2-4 hours every time I finish driving for the charge controller to shut down. it pushes 1 amp at 12v in good sun.

that’s a 50AH battery, taking an additional 2-4 amp-hours every every drive, or roughly 4-8% charge.
 
Fully charging a battery is about voltage control, and the duration of higher voltages allowed by the voltage regulator, wherever it might be located in teh vehicle.

The ideal of a fully charged battery, is an ever moving goalpost which changes with battery state of charge, age and condition and temperature and the position of the nearest locust

ECU control of voltage is not about quickly and fully charging batteries, it is about fuel economy, and never overcharging. Each 25amps an alternator makes takes up one engine HP, as alternators are only ~55% efficient.

People here love to assume one battery is better than another by the sticker on it, and that the only variable affecting battery longevity is the heat it is subjected to, and who made it, or put a sticker on it.

But it is the average state of charge of the battery which has, by far, the largest effect on the longevity of the battery.
Assuming the vehicle's charging system always has the best interest of the battery in mind, is unwise in the extreme.

My Dad owns a 2014 stingray.
The battery is AGM, group 49, and is now 2 years old, I forget the brand/Sticker/reseller.
The vehicle sits a lot. It just barely started when my dad and I took it out. It had been sitting unused for no less than 3 weeks.
When It was my turn to drive I bounced it off the rev limiter several times, we had it out for over an hour and what A joy it is to run it through those first three gears right foot mashed to the floor after letting out the clutch..

When we returned my dad declared the battery had to be fully charged. He was the engineer in his younger years. Has to be right, even when he is not.
I hook up my clamps to battery terminals, and ask him what he thinks the voltage is going to be, after our hour long Sunday drive.
12.7 he declares. I though that surface charge would still have it up at 13.1 or higher.
It read 12.23v.
I hook up my 40 amp adjustable voltage adjustable voltage power supply that I had set to 14.7v before hooking it to the wattmeter.
40 amps flowed for about 3 minutes before voltage rose to 14.7v, and amps begun tapering.

So much for the corvette's charging system quickly charging the battery.
6 hours after bringing the battery to 14.7v, it was still accepting 1.6 amps. Still quite a distance from being fully charged.
4 hours after that it had tapered to only 1.2 amps. As I was going to bed, I lowered voltage to 13.6v and amps tapered to 0.5 after 2 minutes, at that point.
14 hours later held at a constant 13.6v, unobserved, amps read 0.0x.
I cranked voltage back upto 14.7v and amps went as high as 2.3, but quickly tapered to under 0.3 and I removed the power supply.

So 10 hours of being held at 14.7v was not enough to fully charge the battery, after it still had barely enough juice to start the engine and was then driven for over an hour. Several more hours held at 13.6 were required, and to my surprise actually did fully charge the battery.

Even if the stingray was holding 14.7v the entire hour long drive the day previous, which it most certainly was NOT, it would still have taken many many hours on a constant voltage 14.7v charger to come anywhere near close to being fully charged.

If you want to know how well your vehicle takes care of the battery, monitor the voltage it allows, not just after engine starting, but the whole time the engine runs. You will likely be very disappointed in the duration at which 14+ volts is allowed.

When you shut it down, remove any surface charge and put a so called smart charger on it, and see how much longer it takes before the green light comes on. Then if you can dip a hydrometer, check specific gravity. One will likely be disappointed.

Assuming the vehicle is taking great care of a battery and the only variable influencing battery longevity is the average temperature, and who made/stickered/marketed the battery, or how long it is warrantied for, is unwise in the extreme, to put it politely.

It is certainly possible for smart voltage regulation to take much better care of a battery, but they don't bother as timid voltage regulation can be employed to eek out 0.002 more MPG and put more profit in pocket of auto executives, at the expense of the owner of the vehicle's battery.
I didn't realize this until finding out through torque pro that my alternator drops down to less than 13v after driving a bit.

I got a smart (ish) charger and charged it up overnight a couple times and the starter spins much faster again.

I have no proof but it seemed like my 83 Caprice was charging the battery a lot better with its 78 amp alternator than the trucks 200a alternator. Before I got the charger I switched batteries with the one from the Caprice which had already been parked and sitting at the new owners place for a few weeks (my friend bought it from me in exchange for bodywork on my truck). The smaller battery from the car cranked the truck fast again leading me to believe the battery in the truck was on its way out.

A few days later cranking slowed down with that battery also until I charged it up good now it seems to stay sounding strong for weeks. I'll probably charge it once a month especially in the winter.

Checking the voltage right now isn't a very reliable indicator because this week it was above 0c now it's minus 16. Voltage drops a lot with temperature.
 
I'm not convinced that it would make financial sense for East Penn to distribute two lines of AGM batteries given that the type makes up a small percentage of market share for aftermarket batteries.

I'm confident that what you're looking at is the same battery marketed into two difference price tiers, the only difference being the Ultra moniker and the extra year warranty. Batteries Plus is not a volume seller, they are a high(er) margin outfit, so it makes sense that they would extract as much money as they can from the same product by offering an extra year warranty that will rarely get used.

That's my take on it, but you could weigh your Sam's Club battery and compare it against the Batteries Plus (which is stated to be 44.5lb); that ought to confirm it given the ratings are the same.
 
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People here love to assume one battery is better than another by the sticker on it, and that the only variable affecting battery longevity is the heat it is subjected to, and who made it, or put a sticker on it.
Most people are not going to go through the trouble of maintaining charge on their vehicle battery manually at all times. So if you can't (or don't want to) control the vehicle charging characteristics variable, that leaves the quality of battery variable which you CAN control.

I see nothing wrong with researching and purchasing the best battery for the money spent. That should yield extra service life versus buying any battery blindly or a decision based purely on marketing.
 
Alternator amp ratings often mislead consumers. The higher rated alternator in the same physical case size, often has poorer output at lower rpms.
Here is one example:
leece neville power curve copy.jpg


The 185 amp alternator can make 80 amps at 1200 rpm while the 320 amp alternator makes zero. These two alternators are in the same exact size casing

One hoping for better battery charging with an alternator of a higher rating, will often be shooting themselves in the foot. Not always.

But lets say 2 different rated alternators have the same curve, one of them, as rpm raises, is just able to produce more, similar to the 320 vs 270 in chart above. Also lets say the discharged 300 amp/hour battery bank is the only DC load, removing the other variables.
Say the 320 amp alternators voltage regulator only allows 14.0v max, and the 270 amp alternator allows 14.7v.

The 270 amp alternator in this example, will more quickly charge the depleted battery bank in such a scenario and will return the battery bank to a significantly higher state of charge in an hour.

Voltage is electrical pressure. the lower the voltage, the slower the battery charges, and alternators are controlled by the voltage regulator. They can only make so much amperage at specific rpms, but in many cases the amperage ability of the alternator at most any rpm above hot idle, can be considered an unlimited amperage source. The limiting factor in such a case is the voltage regulator, whether it be in the alternator, or on the firewall, or inside the engine computer.

Bitog being Bitog, no one asks "what is the most adequate.......whatever"

Fact is battery longevity is most directly affected by its average state of charge. The higher the better.
It takes a long time for an 80% charged battery to be brought to 100% state of charge. No less than 3.5 hours when held at 14.4v+.

Few vehicles, even if driven for 3.5 hours, ever approach holding these higher ideal charge voltages, and their batteries have no hope of being fully inflated, and they sulfate, losing storage capacity and their ability to quickly delivering what is left to a hungry starter motor. They degrade faster.

A battery that lives in a perpetual state of undercharge, has its potential longevity reduced to a fraction of what it could be if it were returned to 100% after each and every engine start and allowed to live its life at high states of charge.

The battery owner can decide for themselves what additional effort is worth it, but they should know that Ideal battery life is achieved by keeping the battery at high states of charge, and that the best lead acid battery kept chronically undercharged, will not outlast the worse lead acid battery kept fully charged, and that their vehicle does not Shiv one Git about achieving maximum battery longevity.

There is not enough data available to say which Lead acid batteries, easily available, will withstand life in a constant partial state of charge, compared to another, in that same exact usage. Anecdotes of a 5 year old battery having performed well in a specific vehicle in a specific usage, are also meaningless, as the manufacturer of the battery has likely changed in that timespan, to whomever allows the most profit to be achieved, and comparing voltage regulator A to voltage regulator B is a huge variable..

Worrying about which battery might be better, can be negated by the owner realizing their vehicle does not treat the battery very well, and that regularly applying other charging sources to the battery will greatly extend its useful lifespan, even if those additional charging sources themselves are incapable of achieving ideal.

When one tries to achieve ideal, they realize the equipment they own is inadequate.

I've been stunned by just how long it has taken a 'still going strong' battery to achieve a 100% State of charge, by an adjustable voltage power supply, that maintains a high chosen voltage, for as long as I allow it to.

I get frustrated when people assume their vehicle takes perfect care of their battery, and the only thing affecting battery life is the quality of the battery itself.


I know this sounds like an onerous duty, using a manual charging source, but I basically just dial my 40 amp Power supply to 14.7v, hook it to the battery, and watch the ammeter. when amps taper to 0.5 per 100Ah of battery capacity, I lower voltage to float. A large healthy 50% charged battery, this is usually 5.5 to 7 hours. and 6.5 to 12 hours when nearer end of life

If I cannot be there to lower voltage when amps taper to that level, then time to reach full charge is also not important, and I just choose a lower voltage, usually 13.6 to 13.8, but them bump it back upto 14.7v when I can be there to observe amperage.

It takes a long time to truly fully charge a lead acid battery, but especially so on one which has lived most of its life at ~85% state of charge, and reduced/timid charge voltages, increase this time exponentially.

Decide for yourself what is acceptable battery lifespan.

I try to relate what is ideal and how to achieve it, as this is bitog and no body starts a thread asking:
What is the most adequate.......... xxxxxxx?
 
15 year old battery on a seldom driven car and not once on a charger that I can remember. I lived in a big city for a long time where most people live in apartments with no access to outside electricity with cars parked under the building, it is rare to see anyone getting jumped or have a flat battery.
 
A 15 year old battery presumes a 15+ year old vehicle.

One with far less parasitic draw than a newer one.15+ years before manufacturers decided that sacrificing the battery for minimal mpg gains is in their financial best interest.

Also before battery manufacturers were forced by big retailers to really start squeezing out the lead and replacing it with extra fancy marketing.

Watch the voltage on most ant late.model vehicle. Not just immediately after engine start but once hot and cruising along at 65mph. . Many will see 12.7v or less, untill they take their foot off the gas.

People seeking a better battery is fine and dandy. Good.
luck.
But battery ifespan is dictated by average state of charge to a much higher degree, than who made it/marketed it/retailed it.

No lead acid battery is immune to chronic undercharging and trying to claim one or the other is more resistant based on an ancient anecdote with zero details given as to what vehicle, in what type of usage/climate, Is meaningless.
 
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