Done with AGM batteries!

mxthor3 wrote: ↑ Optima really dropped the ball on their batteries. They used to be worth the price premium, now they're garbage.

mxthor3 wrote: ↑I've had AGMs in my vehicles for years, really haven't noticed much of a difference between them an lead acid to be honest.

mxthor3 wrote: ↑ I am on year 3 of 3 group 31 AGMs in my boat which get heavy use and usually drained down to nothing and charged back up overnight. We'll see how long those last for. The lead acids they replaced lasted me 6 years before giving up the ghost.

ES_Revenge wrote: ↑ Yeah once they were sold to JC battery (which in turn is now "Clarios") they went downhill I think. Not in the early stages but once JC started cutting costs, etc. on them (and increasing consumer prices mind you) they've become some kind of insanity. Now made in Mexico or whatever and with all sorts of cost-cutting put in place--ugh. The other problem is at a $300 CAD price point, who the heck is buying these now? Next to no one. So guess what else that means--good luck getting a "fresh" one off a shelf--they've probably been sitting a year plus when anyone does buy one at the insane price!


Yeah it seems the pain erm I mean main difference is on your wallet/account. One is like $120 and the AGM equivalent is like $240, or approx. double the price. It'd be one thing if you consistently got better performance and way more life but in practice it seems that's not the case. Reading reviews on AGMs also reveals the same. The people that say they're great basically got a working battery and are satisfied as, well it's a new battery. The long-term reviews are fewer but the common theme among them is that they didn't last any longer than a battery that cost half as much. There are other benefits, sure, but most of them...are they really worth paying 2x the price? The low ESR and everything, oh yeah that sounds great and all but what's the benefit for the average person? None. About that much The non-spillable and low-gassing nature is of benefit in certain applications but for most people? Just save your money--I think it's the better way to go.


For sure would be interested in seeing some review or follow up a couple years from now to see how they're holding up. Based on my experience I doubt they will do any better but wouldn't mind hearing about it later--cross your fingers! When you talk about three batteries, you're also talking about $300-400 premium over the flooded batts, too I'd imagine?

Would also be interested in hearing from others here who've had AGMs last them like 8-10 years without issue, if any such stories exist!

ES_Revenge wrote: ↑
For sure would be interested in seeing some review or follow up a couple years from now to see how they're holding up. Based on my experience I doubt they will do any better but wouldn't mind hearing about it later--cross your fingers! When you talk about three batteries, you're also talking about $300-400 premium over the flooded batts, too I'd imagine?

cardguy wrote: ↑ just curious...when changing agm on a car that calls for agm...did you "marry" or "pair" the battery to the electrical system?..it my understanding that for AGM to work the way its advertised, this is a must.

cardguy wrote: ↑..as for using agm in non agm type car...i dont think there is a huge benefit

ES_Revenge wrote: ↑ Ha that's just nonsense talk probably so they can have some excuse for why they don't actually fare any better in the long term. Car came with a flooded battery but some versions/trims in ROW do come with an AGM, even when not trunk-installed (which is also an optional setup depending on the engine/trim). There is no such coding option for different batteries, however.

AGM batteries don't have Bluetooth lol, they don't need to be paired. I have the spec sheets and the charge voltage lists (e.g. including temp v. voltage) for both the Edge and the Intimidator. They are the same charge voltages as standard lead acid batteries. In fact these spec sheets caution against over-voltage and the reason is simple--if you gas a sealed battery, there's no way to replace the electrolyte. This is why I've never been a fan of high-voltage desulfation or high-voltage "recovery" of batteries--it's simply a stupid idea on AGMs, which is all I've ever bought in the aftermarket really, but now that has changed of course.


So what is the huge benefit (besides low gassing and being non-spillable) in a car that came with an AGM from the factory? Are you saying that in a car that came with one from the factory, then, and only then, is it going to last any longer? "Trunk batteries" BTW already last longer than "engine-bay batteries" because they are not subject to nearly the heat that many engine-bay batts are. Heat is #1 killer of batteries, and they avoid this by simply not being near any big sources of heat...like an engine. The fact that most of such batteries are AGM now for safety reasons, isn't really what's making them last longer.

cardguy wrote: ↑ I did take an industry sponsored course on batteries a few years ago, both agm and regular , and a lot of what you say is contradictory to what they taught...specifically the "marrying" of the battery (only agm) .

cardguy wrote: ↑ what they taught was MB and BMW (at that time) required the programming or marrying to the system otherwise most of the problems you describe would happen.

true? not true? why would they teach this?..what they said makes sense and what they described is what happened to you

cardguy wrote: ↑i was also told on German vehicles that the ecm actually picks up on a battery identifier?

ES_Revenge wrote: ↑ So what we need a minister now to perform this holy sacrament between the car and the battery? Oh c'mon, an AGM battery is still a lead acid battery at the end of the day. All that happened was they figured out how to absorb the electrolyte into a glass-based mat (as the name implies)...and with Optima roll it into a cylinder... It still has the same operating voltages, the same voltage per cell, the same low energy density (i.e. why they are so heavy), the same general characteristics as a flooded battery, only better. I'm well aware of the science behind how an AGM is made, and how it works. There's no electronics within an AGM battery or any kind of BMS or something like you'd find in an LiFePO4 battery. At it's heart it's still 250yr old technology, only made a little better.

I am not arguing whatsoever that there is no difference here and that these changes and using absorbed electrolyte don't give quite real and measurable improvements over a flooded lead-acid battery. Those things are all there. Not only was I a strong supporter of AGMs earlier, I actually did learn all about how they work, how they're made, and what the on-paper benefits are. They are certainly more rugged and vibration resistant, they certainly have lower ESR and can deliver current better, they should be more temperature resistant...but in the end how much does this actually benefit the consumer in the real world? Are flooded lead acid batteries actually subject to so much vibration in a typical car environment that their lifespan is significantly impacted? Well, apparently not when you compare to a battery that is, by design, much more vibration resistant. So in this regard vibration isn't a problem for regular car batteries even though they are certainly susceptible to long-term problems from physical vibration.

Do people really need better current delivery to start their vehicles on a day-in/day-out basis? Not really because it's not like people using flooded lead acid batteries (which is still the majority of cars out there I would say), ever thought to themselves--hmm I really need more power to start this car! Nah, they just turn the key and it starts and they go about their business. About 5 years later when it don't start so well they get a new battery and...move on with life.


What's the science behind what you are saying? There's no electronics in the battery to "pair or match" to anything. There are no hail marys to be said, religious or cult rituals to perform, so the stars line up "just so" for a damn lead acid battery to work in a car properly, lol. What you're saying might make sense if you're talking about replacing battery packs in a BEV or something where battery performance is so crucial to actually running a vehicle. A battery in a regular fossil-fuel-engined car just serves to start it. Sure it's also a buffer and reserve and all that but really it's not that complicated. Even if you were talking about replacing a lead-acid battery with LiFePO4 then yeah sure those batteries need a BMS to, you know, not catch fire and explode and all that. But what does a lead acid battery, AGM or otherwise need that's so sensitive that if you don't shake salt over your shoulder, hold a seance, have an exorcism done, etc, in order to ensure your precious car battery actually works?

On top of all this point out one battery manufacturer or brand that says any of this or has any sort of disclaimer on AGM batteries, their consumer data in terms of marketing materials, labels, pamphlets that mentions this? Not only that they don't even mention any sort of thing in their more technical documents either (I can give links to some if you want). If it were the case that you had to have programming tools (which I do have incidentally but the majority of the public does NOT), and all kind of rituals, etc. to get one of these uber pricey batteries just to work right then...who would want to buy one? Read any of the FAQs, etc. provided by any of these companies and see where any of them say NO you cannot use these batteries anywhere else except where designed originally and cannot use them without special coding performed. The reality is they say the exact opposite--that anyone can use them and they can replace any regular car battery with no ill effects.

That all said it is true that some cars (many of them now actually) have battery management systems that are coded both for different battery types and for when a new battery is installed. But they don't have to be and the changes the systems make are very minor; furthermore the systems themselves can already detect when a new battery has been installed or when one exists with lower ESR, etc. So the coding simply isn't 100% necessary.


Oh c'mon man, how would it do that if there's no electronics in the battery? You can code the battery/energy management module for the matching part# on the battery and can specify a new battery is installed but it's not 100% necessary either. Not only that most cars these days German and otherwise do have some sort of energy monitoring/management even if they don't have such very-specific coding options. Some of the cars mentioned here have exactly that--the car's system knows when to inhibit things like seat heating, and other accessories when the energy needs to be used to recover a battery in low SOC for example. BMW used to refer to this as part of their "Efficient Dynamics" thing but many other modern cars have this working behind the scenes without some kind of tradename having to be mentioned.

Anyway as mentioned I'm not trying to argue there are not any technical or scientific differences and actual improvements in AGM batteries over flooded ones. There certainly are. My point is just that, in my experience these benefits have not meant anything meaningful in my real-world use. Only one of four batteries has done anything impressive and these are all ~$200+ batteries if you account for inflation. AGMs have not gotten any cheaper over time, as I mentioned and IMO they certainly should have. But adoption has been slow and costs have remained stagnant at best and it's probably not surprising given the real world benefits just aren't there for the consumer.

I'm only bothering to post this because I see a lot of people posting the same thing I myself have posted in the past. That AGM is better and bestest evar, and what people should be buying if they can afford it, and it's so worth buying and all that crap. And that's what it is, my own previous advice included--crap. I'm simply posting this to tell people that's really not true and they aren't worth it. Sure they are "better" but not really in the way that's meaningful to the end consumer. Most importantly they're not, IMO, worth double the money. If they were like $30-40 more than a regular battery, I'd still be buying another one now. But at 2x the cost? After how much money I've already put into these so-called "ultimate" batteries? Uh no thanks. Even if they were commonly lasting 7-8 years that would be something but it doesn't seem like they can even go that long--longevity certainly isn't a big thing here and the fact that none of them has a truly long warranty any longer, is just more proof of that.

Just putting this out there as actual experience so people can make their own decisions. My recommendation is just for people to save their money here and buy a flooded battery for any engine-bay-battery application. That's what RFD is all about anyway--saving people money, right? I never recommend buying "cheap crap" because it's cheap as it's not going to be good; but at the same time I'm not going to recommend spending twice the money on something I cannot, in good conscience, say is any better than the thing that costs half the money.

angryaudifanatic wrote: ↑ ............
Whoever thought it was a good idea to put any battery in the engine bay of a car should be shot.

Possum77 wrote: ↑ Volvo's OEM lead-acid battery -11 years. (German nade)

cardguy wrote: ↑ I was only questioning why a professional from East Penn would train and speak about the differences and contradictory statements that you made...i dont really care either way, but..they are the manufacturers and are you saying they are wrong or BS'ing?

angryaudifanatic wrote: ↑ Carmakers are just stupid. Many Audi models have an AGM battery (12v) as standard but the battery belongs where it SHOULD be, which is in the trunk.

Whoever thought it was a good idea to put any battery in the engine bay of a car should be shot.

cardguy wrote: ↑ I dont know 100%

but...

I did take an industry sponsored course on batteries a few years ago, both agm and regular , and a lot of what you say is contradictory to what they taught...specifically the "marrying" of the battery (only agm) .

what they taught was MB and BMW (at that time) required the programming or marrying to the system otherwise most of the problems you describe would happen.

true? not true? why would they teach this?..what they said makes sense and what they described is what happened to you

i was also told on German vehicles that the ecm actually picks up on a battery identifier?