AGM Batteries

[floridafarmer]

I've been using Optima batteries in my military generators and yesterday I went to start it and click and my battery meter shows one of the red-tops has had it.
So I started doing some research and a red top in my group size is about 200 bucks but I'm seeing some AGM offerings from Duracell that are about 150 bucks.
I watched a few videos and I think Optima is an AGM construction (spiral) and they also now offer a non-spiral version.

I'm just curious if any of you have bought a non-spiral AGM battery and how it worked for you. Saving 50 bucks is helpful but not worth the savings if the performance and longevity isn't there.

Appreciate you comments.
Thanks

 

[Moosefire]

Just a heads up I believe you're supposed to change all agm at the same time not just 1...

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[Jking24]

Have used many they are great as long as they don't go completely dead when they do it takes more than just a trickle charger to bring them back up and they don't take that very many times before their junk. Mercedes has had agm standard since the mid 2000s. ive had very mixed results with optima so i wouldn't hesitate to try a competitor. Truth be told their aren't that many actual battery manufacturers out their so their is a high possibility they all come from the same place.

 

[Showkey]

Have used many they are great as long as they don't go completely dead when they do it takes more than just a trickle charger to bring them back up and they don't take that very many times before their junk. Mercedes has had agm standard since the mid 2000s. ive had very mixed results with optima so i wouldn't hesitate to try a competitor. Truth be told their aren't that many actual battery manufacturers out their so their is a high possibility they all come from the same place.

True..........but the branded batteries are built to a spec and or price point........so just because they are made in the same factory........they can be completely different in performance and longevity.

 

[Bogie1632]

I've been using Optima batteries in my military generators and yesterday I went to start it and click and my battery meter shows one of the red-tops has had it.
So I started doing some research and a red top in my group size is about 200 bucks but I'm seeing some AGM offerings from Duracell that are about 150 bucks.
I watched a few videos and I think Optima is an AGM construction (spiral) and they also now offer a non-spiral version.

I'm just curious if any of you have bought a non-spiral AGM battery and how it worked for you. Saving 50 bucks is helpful but not worth the savings if the performance and longevity isn't there.

Appreciate you comments.
Thanks

The non-spirals are fine. Like any battery. They don't like sitting unused for long periods of time. Anything you have sit I'd recommend putting a battery tender on.

Sure you can't bring that Optima back from the dead? I've had some that sat for over a year at less than 1 volt and recovered them, but it took some time. Before you get a new one I'd recommend a low, slow charge, then a full discharge. Might take a few times doing this but I've had success getting them to come back using just a 1.5A trickle charger. Can't hurt to try if you have the time. Had to do this often when I ran a shop in Korea that had swapped dang near every battery in our fleet to Optima. Lots of dead batteries in our War Readiness Materials fleet that just sat unused. Even had my own sit 2 different times for 6 months, untouched during deployments, recover and last 14 years total before I traded my truck in.

Good luck.

V/R
Bogie

 

[jabin]

Just a heads up I believe you're supposed to change all agm at the same time not just 1...

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Yes, the old one will cause the new one to work harder shortening its life.

 

[Captain Spaulding]

The Duracell AGMs are pretty decent. They are just relabeled Dekas.

AGMs are generally more physically robust in off-road and high vibration applications than conventional batteries and the spiral cells are the most robust of all.

 

[toplessHO]

Optimas went down hill fast when JC took over
Now I buy any AGM except Optima

 

[Captain Spaulding]

Optimas went down hill fast when JC took over
Now I buy any AGM except Optima

Happened 20 years ago.

 

[theoldwizard1]

The non-spirals are fine. Like any battery. They don't like sitting unused for long periods of time. Anything you have sit I'd recommend putting a battery tender on.

Optima change their manufacturing several years ago and the new ones are "not as good" as the old ones.

Despite what the "experts" tell you, no battery likes to be connected to a "tender" 24/7 for months at a time. Simple solution is to connect the tender to an old fashioned mechanical lamp timer and only let it run for 2-4 hours/day.

If you use the battery and think it needs more of a charge, just flip the lamp timer to on when you connect the battery. That should give you 12+ hours.

 

[pmiranda]

I've had good luck with the Autozone house brand of AGM in our convertible. I throw the battery tender on it once a month and it's been happy for several years so far.

 

[Jdsmith]

I would also recommend an AGM, and I agree with the general sentiment to stay away from Optima spiral type AGMs. If a flooded lead cell is deep discharged a couple times it will be basically shot*. AGMs are more resistant to deep discharging.

It is possible to keep a battery charger connected 24/7 without ruining the battery, it just has to apply the proper float voltage, then periodically apply a higher charging voltage similar to the approach above with the lamp timer. I have a charger in my camper that is plugged in most of the time. It is programmed to float at the voltage specified in the battery instruction manual. Gel, AGM, and flooded batteries all prefer a slightly different float voltage. I have a CTEK smart charger that can be connected 24/7 as well without ruining the battery. It includes modes for flooded, gel, and AGM batteries and will output the proper float voltage and then attempt a charge a few times a day. Noco also makes smart chargers, although I don't know the details of them as well as the CTEK. There are smart battery tenders available with 1-2 amp ratings. My CTEK smart charger is rated at 7 amps - I can leave it on a lawn mower or something all winter as a tender if desired, or it will charge a common auto battery overnight. Higher powered smart chargers (10A, 40A, etc) are available, however the price goes up quickly. The old style chargers with a voltage selector and a timer will still work, but they'll never get the optimal charge level on the battery, they'll always be over or under. The only use I have for the old timer type chargers is for the cranking assist mode if another vehicle is not available to jump start something.

As batteries in my vehicles need replaced I have been changing them to AGM (not Optima brand) to get the benefit of increased resistance to deep discharging as well as a flatter temperature vs cranking amp relationship. The best AGM I have found from a technical standpoint is Lifeline, but they are not readily available a lot of places. If you need a deep cycle and can wait a couple weeks they're worth a look. I use whatever non-Optima AGM is handy for my vehicles, which has included the Enersys Northstar and Deka/East Penn under a couple different brand labels.

*There are some reports of using a constant current charger to bring flooded cells back from the dead but I have not personally tried it. There is a significant hazard of overheating the battery, so I would be hesitant to start a multi-day constant current recovery procedure without a power source that can monitor the battery temperature and shut off the charger if the battery overheats. I maintain a large fleet of batteries at work, but ours have protection built in to disconnect the battery when it gets down to 1.75 V/cell, so I'm not experienced trying to recover deeply discharged jars.

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[OddlySpecific]

Another vote to stay away from Optima. I was a loyal customer for many years but the last one I bought was junk.

 

[SGKent]

lots of the newer battery tenders have programming designed to help bring back a chemically dead battery - meaning one that died because it sat and the chemistry went belly up. However if the physical battery is damaged internally you can't bring that back.

 

[Showkey]

Optima change their manufacturing several years ago and the new ones are "not as good" as the old ones.

Despite what the "experts" tell you, no battery likes to be connected to a "tender" 24/7 for months at a time. Simple solution is to connect the tender to an old fashioned mechanical lamp timer and only let it run for 2-4 hours/day.

If you use the battery and think it needs more of a charge, just flip the lamp timer to on when you connect the battery. That should give you 12+ hours.

Disagree as long as the “tender” is a quality unit with a true float charge cycle.
Accumate or CTEK come to mind of the high quality chargers tenders.

If the charger is a $10-$20 “tender” that lacks multiple stages of charging then I agree to long term connection might damage or give marginal results.

The real beauty of AGM is they have a very low self discharge rate. My diesel RV chassis battery is a AGM that sits disconnected in the RV for 5-6 months storage at temperatures from 60* to -30* (actual) with no charger attached. It starts in April with no jump and no added charge.

 

[finn]

Never tried it, but you can supposedly bring a dead battery back to life by connecting it to a good battery in parallel and slapping it on a trickle charger.

I have a deceased Napa branded a AGM that’s ready for that experiment when I get home.

 

[az45]

The Duracell AGMs are pretty decent. They are just relabeled Dekas.

AGMs are generally more physically robust in off-road and high vibration applications than conventional batteries and the spiral cells are the most robust of all.

True, its a good battery. Get a proper charger, I use the larger C Tek with a refurbish function.

 

[unslow1]

Never tried it, but you can supposedly bring a dead battery back to life by connecting it to a good battery in parallel and slapping it on a trickle charger.

I have a deceased Napa branded a AGM that’s ready for that experiment when I get home.

I've done it a lot. Probably 1 in 3 it will bring the battery back. A lot of new chargers won't attempt to charge a very low battery.

 

[gearhead1]

Never tried it, but you can supposedly bring a dead battery back to life by connecting it to a good battery in parallel and slapping it on a trickle charger.

I have a deceased Napa branded a AGM that’s ready for that experiment when I get home.

Yes! An AGM can come back after being more discharged as compared to a wet cell. That’s one advantage of them. Optima’s website said to do this.

 

[gearhead1]

I've done it a lot. Probably 1 in 3 it will bring the battery back. A lot of new chargers won't attempt to charge a very low battery.

A lot of chargers are designed for wet cells and they will not charge a deeply discharged battery. I bought an Optima battery charger that will. That was before I knew about the battery in parallel trick.

 

[mwalsh9152]

Optima went to **** when JC moved the manufacturing to Mexico.

Odyssey or Northstar are tops in the AGM market.

 

[kald]

Yes! An AGM can come back after being more discharged as compared to a wet cell. That’s one advantage of them. Optima’s website said to do this.

You are the victim of marketing speak.

Flooded lead acid batteries have a greater capacity for a depth of discharge then AGM(absorbed glass mat -baby diaper)
The agm is effectively not as discharged as a flooded battey hence why it will come back.
Over discharging agms will extremely shorten the life of the batteries in comparison to a flooded battery though.

 

[ScaldedDog]

You are the victim of marketing speak.

Flooded lead acid batteries have a greater capacity for a depth of discharge then AGM(absorbed glass mat -baby diaper)
The agm is effectively not as discharged as a flooded battey hence why it will come back.
Over discharging agms will extremely shorten the life of the batteries in comparison to a flooded battery though.

Whichever, in real life, the Diehard Platinums (Odyssey AGMs) in my seldom used tow rig and crawler have been discharged many times and left that way, and have always come back by simply hanging them off my Odyssey charger. The ones in my tow rig are 8-9 years old and have to be near the end, but I've been saying that for years.

Mark

 

[SGKent]

A lot of chargers are designed for wet cells and they will not charge a deeply discharged battery. I bought an Optima battery charger that will. That was before I knew about the battery in parallel trick.

My CTEK has specific cycles for RV, ATV/Motorcycle, Car and AGM. It has 7 steps that vary voltage and pulse frequency to condition a battery. This is a real improvement over the older chargers I have that simply apply voltage for "X" period of time. It is designed to pulse charge discharge to help begin a healing process on a defective battery. It cannot fix a physically damaged battery where plates have buckled, material fallen to the floor of the battery etc.. All that said, another classic car forum I belong to many people said they stopped buying Optima batteries four or five years ago when they started seeing failure after failure, sometimes only months into ownership.

 

[toplessHO]

I would also recommend an AGM, and I agree with the general sentiment to stay away from Optima spiral type AGMs. If a flooded lead cell is deep discharged a couple times it will be basically shot*. AGMs are more resistant to deep discharging.

It is possible to keep a battery charger connected 24/7 without ruining the battery, it just has to apply the proper float voltage, then periodically apply a higher charging voltage similar to the approach above with the lamp timer. I have a charger in my camper that is plugged in most of the time. It is programmed to float at the voltage specified in the battery instruction manual. Gel, AGM, and flooded batteries all prefer a slightly different float voltage. I have a CTEK smart charger that can be connected 24/7 as well without ruining the battery. It includes modes for flooded, gel, and AGM batteries and will output the proper float voltage and then attempt a charge a few times a day. Noco also makes smart chargers, although I don't know the details of them as well as the CTEK. There are smart battery tenders available with 1-2 amp ratings. My CTEK smart charger is rated at 7 amps - I can leave it on a lawn mower or something all winter as a tender if desired, or it will charge a common auto battery overnight. Higher powered smart chargers (10A, 40A, etc) are available, however the price goes up quickly. The old style chargers with a voltage selector and a timer will still work, but they'll never get the optimal charge level on the battery, they'll always be over or under. The only use I have for the old timer type chargers is for the cranking assist mode if another vehicle is not available to jump start something.

As batteries in my vehicles need replaced I have been changing them to AGM (not Optima brand) to get the benefit of increased resistance to deep discharging as well as a flatter temperature vs cranking amp relationship. The best AGM I have found from a technical standpoint is Lifeline, but they are not readily available a lot of places. If you need a deep cycle and can wait a couple weeks they're worth a look. I use whatever non-Optima AGM is handy for my vehicles, which has included the Enersys Northstar and Deka/East Penn under a couple different brand labels.

*There are some reports of using a constant current charger to bring flooded cells back from the dead but I have not personally tried it. There is a significant hazard of overheating the battery, so I would be hesitant to start a multi-day constant current recovery procedure without a power source that can monitor the battery temperature and shut off the charger if the battery overheats. I maintain a large fleet of batteries at work, but ours have protection built in to disconnect the battery when it gets down to 1.75 V/cell, so I'm not experienced trying to recover deeply discharged jars.

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Getting mixed signals on this.
Just yesterday I called Battery Minder and asked about the Battery Minder Plus TC that I recently purchased.
I have one connected to a wet cell,another connected to AGM.
one is at a float state of 13.02v the other is at a float state of 13.04v.
I asked the tech guy about the fact that the AGM was being charged at same voltage and the comment back was "thats old school thoughts"
They supposedly bumped the voltage up a little on the newest Battery Minder
but the charge voltage is otherwise the same for flooded and AGM.

 

[PWC Repair]

I've used AGM and Gel for years in my play toys. I've sold 6 AGM batteries for watercraft this season already. People buy the cheapest liquid battery they can find......and they won't last a year in a watercraft.....too much vibration. My "shop" battery is Gel with a digital voltage display. It's been in and out of more watercraft for cranking and troubleshooting in the last 2 years than you can count. Has also bounced off the 4 wheeler rack while riding across the yard a couple times!!! Still going strong. I usually get around 5 years out of mine.

 

[kald]

Getting mixed signals on this.
Just yesterday I called Battery Minder and asked about the Battery Minder Plus TC that I recently purchased.
I have one connected to a wet cell,another connected to AGM.
one is at a float state of 13.02v the other is at a float state of 13.04v.
I asked the tech guy about the fact that the AGM was being charged at same voltage and the comment back was "thats old school thoughts"
They supposedly bumped the voltage up a little on the newest Battery Minder
but the charge voltage is otherwise the same for flooded and AGM.

As long as the voltage does not venture into the gassing territory of 2.37 vpc or 14.22 volts you are fine.

AGM cannot tolerate a higher voltage that a flooded requires to mix the electrolyte and prevent stratification.

 

[kald]

I've used AGM and Gel for years in my play toys. I've sold 6 AGM batteries for watercraft this season already. People buy the cheapest liquid battery they can find......and they won't last a year in a watercraft.....too much vibration. My "shop" battery is Gel with a digital voltage display. It's been in and out of more watercraft for cranking and troubleshooting in the last 2 years than you can count. Has also bounced off the 4 wheeler rack while riding across the yard a couple times!!! Still going strong. I usually get around 5 years out of mine.

AGM and GEL have their uses, I can see how one with extreme vibration would be one. Gen-set batteries not frequently started is another.

They are derived from Stationary/Backup technologies and IMO anyone using one (agm or gel) in a typical automotive application is throwing money away. Even in a "heavy duty" automotive application so many think they have they are a complete misapplication.

I have been in the Industrial Motive Power battery business for almost 35 years now and have even seen where they tried to put them in forklifts which failed miserably. Only the geniuses at the post office still use them, shocking i know.

 

[Bogie1632]

x2 of forklifts being a bad idea. Replaced literally hundreds back to a wet cell. HMMWVs (Humvees), or any M-series for that matter, also **** with AGM/GEL. Once had a genius put 6 Optimas in a Dresser loader. After the battery switch was left on and they all died they wondered why it was so hard to jump start and wasn't charging all 6 correctly. Putting 2 correct sized wet cells fixed that problem. Some applications they work great, others not so much.

V/R
Bogie

 

[schurtjl]

I’m a huge fan of the Northstar AGM’s. I have a pair in my boat that are 9 years old and still going strong. They are isolated so if one fails, the other will still start either the main or kicker motor.

 

[floridafarmer]

Thanks for the comments - I went with the Duracell AGM Marine and RV Deep Cycle from Sams Club - group 34 for 114 bucks. In the past I would have not bought a deep cycle for starting but that's what they say this "dual purpose" battery will do. It spun the generator like a champ so now time will tell on the longevity. Considering all the comments on smart chargers - I'm looking at buying a few of the Harbor Freight Viking 4A chargers - supposed to be better for AGM than my old traditional chargers.

 

[gearhead1]

You are the victim of marketing speak.

Flooded lead acid batteries have a greater capacity for a depth of discharge then AGM(absorbed glass mat -baby diaper)
The agm is effectively not as discharged as a flooded battey hence why it will come back.
Over discharging agms will extremely shorten the life of the batteries in comparison to a flooded battery though.

I hear you. I guess this is just marketing? Reminds me of the Coronavirus, just not sure what to believe anymore.

https://batteryuniversity.com/learn/article/absorbent_glass_mat_agm

“The leading advantages of AGM are a charge that is up to five times faster than the flooded version, and the ability to deep cycle. AGM offers a depth-of-discharge of 80 percent; the flooded, on the other hand, is specified at 50 percent DoD to attain the same cycle life. The negatives are slightly lower specific energy and higher manufacturing costs than the flooded, but cheaper than the gel battery.”




One of the reasons I use them is for my demolition derby cars due to the rough service (vibration). Also they sometimes sit a while in derby cars and in my tractors over winter. I’m probably lucky I guess because they’ve worked just fine for me. A demo derby friend had one for 10 years - in derby cars (an Optima), which is why I started using them. Seem to work good for me. YMMV.

 

[kald]

I hear you. I guess this is just marketing? Reminds me of the Coronavirus, just not sure what to believe anymore.

https://batteryuniversity.com/learn/article/absorbent_glass_mat_agm

“The leading advantages of AGM are a charge that is up to five times faster than the flooded version, and the ability to deep cycle. AGM offers a depth-of-discharge of 80 percent; the flooded, on the other hand, is specified at 50 percent DoD to attain the same cycle life. The negatives are slightly lower specific energy and higher manufacturing costs than the flooded, but cheaper than the gel battery.”




One of the reasons I use them is for my demolition derby cars due to the rough service (vibration). Also they sometimes sit a while in derby cars and in my tractors over winter. I’m probably lucky I guess because they’ve worked just fine for me. A demo derby friend had one for 10 years - in derby cars (an Optima), which is why I started using them. Seem to work good for me. YMMV.

The "battery university" blurb is jibberish!
It has it backwards about the different technologies and depth of discharge -DOD. Also the ability to be charged faster is because of the lower internal resistance. You could never reliable archive this due to heating. It's not benefit that would ever be realized outside of a lab.

As I said earlier, AGMs have their place such as in your cars with impact/vibration, saltwater contamination, long periods of inactivity and a few others.
But the are largely in the market place the present a solution to a problem which doesn't exist. All at a $$$ premium and very high profit margin where car batteries have all but become a commodity.

As an example of automotive battery BS - Exide for decades rated their battery capacity at a higher temperaure than the industry standard of 77f. This allowed them to sell smaller batteries to an unsuspecting public.
They even played this game in the industrial market as well with high gravity tubular products.

There is so much battery marketing swill it's crazy.

 

[toplessHO]

The "battery university" blurb is jibberish!
It has it backwards about the different technologies and depth of discharge -DOD. Also the ability to be charged faster is because of the lower internal resistance. You could never reliable archive this due to heating. It's not benefit that would ever be realized outside of a lab.

As I said earlier, AGMs have their place such as in your cars with impact/vibration, saltwater contamination, long periods of inactivity and a few others.
But the are largely in the market place the present a solution to a problem which doesn't exist. All at a $$$ premium and very high profit margin where car batteries have all but become a commodity.

As an example of automotive battery BS - Exide for decades rated their battery capacity at a higher temperaure than the industry standard of 77f. This allowed them to sell smaller batteries to an unsuspecting public.
They even played this game in the industrial market as well with high gravity tubular products.

There is so much battery marketing swill it's crazy.

next time you have a leaking flooded battery and it eats into the subframe(under the rear seat) or eats up suspension components(under the drivers side front fender) maybe you will change your mind.

 

[kald]

next time you have a leaking flooded battery and it eats into the subframe(under the rear seat) or eats up suspension components(under the drivers side front fender) maybe you will change your mind.

Foolish strawman argument. Lol, really laughed pretty hard at this!

 

[Showkey]

Trust the battery university long before the jibberish is on the GJ.

 

[nadogail]

Back in my high school days I spent several summer days in the Rail Road Yards. The Car Lighting Batteries I saw were many years old and were made by the Edison Battery Company.

 

[kald]

Trust the battery university long before the jibberish is on the GJ.

Trust what you want and believe whatever makes you feel better.
I will rely on almost 35 years of design, implementation, sales and service of Industrial Batteries, charging systems & related equipment experience.

 

[kald]

Back in my high school days I spent several summer days in the Rail Road Yards. The Car Lighting Batteries I saw were many years old and were made by the Edison Battery Company.

That's cool! Have never dealt with Edison batteries. Nickel iron?
I think they still use them in some stationary applications.

 

[n20junkie]

Odyssey AGM are what you want. Optima are junk now and just coast on their old reputation.

I got 10 years out of my Odyssey and replaced it with another. That battery served almost a generator life (it was in my race car). It sat for long periods and was asked to do a lot of work all at once and it never let me down.