AGM battery life?

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Sparksalot

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I’m curious how long AGM batteries last as vehicle batteries. In my case, my vehicle has a matched pair that were in it when I bought it. The date codes are late 2016. For a standard car battery, they would be on borrowed time already.

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Personally, I am an engineer with specific experience in commercial/military battery systems. I have run AGMs since they came out. I have found that a well maintained lead acid battery lasts as long if not longer than an AGM. I have been through 5 AGMs in personal vehicles. I find they do not tolerate abuse nearly as well as a standard wet cell lead acid. Run them dead a couple of times and things go downhill fast, and I tend to run the deep cycle AGMs. Leaving them dead in the winter is the kiss of death. Having said that, I have friends who swear by them and have had no issues. I have had nothing but issues, and I keep my charging systems in top notch condition and I use AGM specific chargers.
 
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diabetiktaco

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Personally, I am an engineer with specific experience in commercial/military battery systems. I have run AGMs since they came out. I have found that a well maintained lead acid battery lasts as long if not longer than an AGM. I have been through 5 AGMs in personal vehicles. I find they do not tolerate abuse nearly as well as a standard wet cell lead acid. Run them dead a couple of times and things go downhill fast, and I tend to run the deep cycle AGMs. Leaving them dead in the winter is the kiss of death. Having said that, I have friends who swear by them and have had no issues. I have had nothing but issues, and I keep my charging systems in top notch condition and I use AGM specific chargers.
I agree. Also, people who are running an AGM are usually doing so for a reason. Like me. My single 94 R should really be a dual battery system and it's got a lot of stuff running off of it. It won't last nearly as along as a flooded battery in a toyota corolla.
 

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If you never take your AGM down below 50% they will last a VERY long time. My AGM sump pump backup battery is ten years old and still perfect performance. The AGM in my 2007 motorcycle is the original battery. Still going strong! And the two group 31 in my travel trailer are going on 6 years and still perfect. And my boat.....Keeping them charged with a proper charger and they will give great service. And require no maintenance like a lead acid.
Any engineer knows you NEVER let any battery go to a dead state......especially in freezing temperatures. Never discharge below 50% and they will give you amazing service.....
 

Sparksalot

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Personally, I am an engineer with specific experience in commercial/military battery systems. I have run AGMs since they came out. I have found that a well maintained lead acid battery lasts as long if not longer than an AGM. I have been through 5 AGMs in personal vehicles. I find they do not tolerate abuse nearly as well as a standard wet cell lead acid. Run them dead a couple of times and things go downhill fast, and I tend to run the deep cycle AGMs. Leaving them dead in the winter is the kiss of death. Having said that, I have friends who swear by them and have had no issues. I have had nothing but issues, and I keep my charging systems in top notch condition and I use AGM specific chargers.
I'm a bit confused by your note. It sounds like you use them, but hate them????
 

Sparksalot

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I agree. Also, people who are running an AGM are usually doing so for a reason. Like me. My single 94 R should really be a dual battery system and it's got a lot of stuff running off of it. It won't last nearly as along as a flooded battery in a toyota corolla.
They were installed for a very specific reason. My car was a highway patrol interceptor in it's past life. Lights, sirens, radios, radar, LOL. I'm sure Texas DPS wouldn't spring for the added cost without reason.
 

Sparksalot

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If you never take your AGM down below 50% they will last a VERY long time. My AGM sump pump backup battery is ten years old and still perfect performance. The AGM in my 2007 motorcycle is the original battery. Still going strong! And the two group 31 in my travel trailer are going on 6 years and still perfect. And my boat.....Keeping them charged with a proper charger and they will give great service. And require no maintenance like a lead acid.
Any engineer knows you NEVER let any battery go to a dead state......especially in freezing temperatures. Never discharge below 50% and they will give you amazing service.....
Good to know on the motorcycle, lots of vibration and environmental factors there. The travel trailer is probably a pretty cushy gig. LOL
 

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I bought a Diehard Platinum AGM battery used in 2009 and it just died late last year. It was ~1 year old when I bought it so it made it through 11 years of abuse on the trail, running a winch, and being heavily drawn down many times. A friend had the same battery (different size) and his lasted 8+ years under similar conditions.
 

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Running a pair of Duralast Platinum ( Johnson Control) 34r s in our cruiser. 95,000 miles, 6.5 years old, multiple draw downs on the house battery and still going strong. I recently replaced the house battery with an Optima ( Johnson Control ) 27m, not because it was needed, I just wanted to up my amp hours. If the starter battery ever goes, I have the spare on my bench staying charged up. Before these I had a single Diehard Platinum in a vehicle I sold that lasted at least 5 years. I’ll never go back to old school wet batteries.
 

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I'm a bit confused by your note. It sounds like you use them, but hate them????
What's more irritating at his post to me is that he says he knows how to handle and has top notch management but mistreats and abuses his batteries constantly.

Under severe conditions a normal life span of a agm battery should be around 3 years. Under normal conditions it should hold up much longer. I had one in a vehicle that I've sold after 8 1/2 years, the stock battery was down after about 2 1/2 years. Put in a good quality agm starter battery and never touched it again.
 

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I'm a bit confused by your note. It sounds like you use them, but hate them????
I don't hate them but I understand that they are not the answer to every problem. I use them because I can get them cheap and they handle the extreme angle and bouncing without venting all over everything.
 

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I use them because I can get them cheap and they handle the extreme angle and bouncing without venting all over everything.
Same here.
First off, not all AGM's are created equal. I've gotten 5-6 abused years out of my Odyssey batteries. I've seen Optima's die in 2 years and the auto zone AGM go 5. How you treat it is important. Most people buy AGM's for the "cool" factor and they read in a forum that's what they need. No spill is a big factor when I rock crawled.
I run lead acid in my campers and trailers. Not picky, hold up well and last as long. I like my AGM's for the extra capacity and just deal with the fact their picky about being charged.
 
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My favorite benefit of the sealed agm batteries is the fact that the battery terminals do not corrode since there is no sulfuric acid fumes venting...
 
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any graph from the manufacturer tells the complete story. YOu discharge them less at 50 % or less, the cycles they will endure drop from 2500 cycles to 500.. so 5 TIMES less..
same with temperature. at 20 degrees they last 7-8 years, at 40 degrees celsius ( 104 F) the life goes down from 7 years to 4....
 

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My original factory regular lead acid battery in my F-150 lasted 3 years. Sears was going out of business so I picked up a Diehard AGM and it lasted 5.5 years in my truck before it started to go. I replaced it with another AGM battery without hesitation and made sure this one had more ah in reserve, this one has 90 ah compared to 75ah of my previous battery. I don't run anything off but my truck but I can leave a dome light on or something else on and it will still start in the morning. I also can use it to run my refrigerator for 24 hours and still have enough juice to start the truck, comes in handy and serves as a backup for the other 90ah battery that runs my refrigerator.
 
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Sparksalot

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My original factory regular lead acid battery in my F-150 lasted 3 years. Sears was going out of business so I picked up a Diehard AGM and it lasted 5.5 years in my truck before it started to go. I replaced it with another AGM battery without hesitation and made sure this one had more ah in reserve, this one has 90 ah compared to 75ah of my previous battery. I don't run anything off but my truck but I can leave a dome light on or something else on and it will still start in the morning. I also can use it to run my refrigerator for 24 hours and still have enough juice to start the truck, comes in handy and serves as a backup for the other 90ah battery that runs my refrigerator.
Thanks for the feedback. yep, a standard lead-acid battery will last 3 years. Period. The extended life of the AGM sounds good.

I have big auxillary power feeds, 60 and 125 amps, from mine that are very lightly used when the vehicle is parked. I've contemplated a fridge, but for my trailer, not the TV itself. I'd likely add a more robust solar array if I did that on the trailer as well.
 
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