Carsy

We know that when acid is added to a dry flooded battery the clock begins ticking on its lifespan. Battery retailers can store the battery dry until customer purchase. If the acid is added on manufacture it is essential to check the manufacture date to procure a fresh battery,

I would be interested to know the story of how or if storage life is managed with AGM batteries?.

They seem to last well, mine being almost. 9 years old & I have heard of them going strongly well after 10 years.

cvx5832

I imagine the AGM's degrade as soon as they're produced as you suspect. But with the long life of the average AGM battery plus today's on-demand and tighter supply chains it's no longer a factor as they're still marketed with the same "life". Put differently -

I hear 5-7 year replacement cycle recommended most often. With a battery that can last 10 years, it can tour the supply chain and sit in warehouse after warehouse for a full three years before it's "recommended life" starts to shorten, effectively making it a non-issue.

Carsy

Mate,

Three years should be an issue to any purchaser.ie 30% life span.

You are too wealthy , not a careful consumer or both to think like this.

I asked for an experts advice. I do not value yours.

CGC

Having been in the automotive industry for over 20 years, CVX5832 is correct. You might not like the answer, but that doesn't mean it's not true. With just in time inventory they probably don't sit that long though.

Carsy

I would be interested to know the story of how or if storage life is managed with AGM batteries?.

I was hoping to hear more from manufacturing/engineering points rather than the sales inventory story.

Does the AGM battery 'shelf store' better than the flooded?.

cvx5832

I think I remember you. I may have insinuated at some point long ago that you didn't know how to wrench.

I apologize for the 8-yr butt hurt. That's a long time to carry a grudge. Like my response here I meant to share an alternate point of view, not a sleight.

Let it go man, you'll probably live longer (assuming you want to).

Carsy

Getting back to your statement "sit in warehouse after warehouse for a full three years before it's "recommended life" starts to shorten, effectively making it a non-issue. "

That is pure nonsense to anyone who wishes to have long life out of a battery.

Never heard of you or remember you, thankfully. .I have earned my bread & butter on the tools for 40 years . So another of your thoughtless throw away lines.



Just heard from another MB forum :- "Just changed my AGM main in June. It was in service for 10 years 4 months. " He would have only had 7 years with your philosophy.

Josh.A.Hussey

To stay on topic here (as this is a car community not an elementary school playground) I believe what they are trying to say is that the batteries are engineered to last 10 years. They are marketed to have a recommened life of seven so that EVEN IF... IF... ***IF*** they are sitting for anywhere from 1-3 years, then they can still guarrentee 7 years out of the battery. If you get a fresh one than lucky you! You'll get more than the stated lifespan!

As for engineering/technical specs.

AGM batteries by nature are much less prone to sulfation than flooded batteries. I.E. they store better, yes.

There are many pros to AGM batteries including weight, but you need to be careful, you generally won't get the advertised life out of the battery if you replace a flooded battery with an AGM battery that's being deep cycled if the generation system is not correctly configured.

If you'd like to know more, try google "Self-Discharge".

You can report back with you personal experiences with them in 7-10 years!!




EDIT: I've just realized I've not answered you initial question.
Seeing as they are manufacturer sealed batteries by nature, no, I've never seen them "deactivated" (for lack of a better term) before customers purchase. I believe the main reasons for this are above (and the fact that they are sealed batteries.)

Carsy

Thank you Josh.Good info..esp. about the "generation system"

But Mr. Hussey, what I am trying to point out, & getting myself into trouble in the process, is that it is not luck to" get a fresh one". It is just a matter of making sure you do. I ask for a good date & if one is not forthcoming, I purchase elsewhere.

Alfadude

I understand what you are saying about buying the 'freshest" date battery and it makes sense in that you increase your chances of it lasting longer. But how will you know how fresh is fresh enough and when to buy and when to keep shopping? Say, you go somewhere and you see the date is 6 months old? Will you keep shopping around until you find one 3 months? Three days? I guess it is possible to find an old battery that has been sitting around at a store for a long time, but as someone pointed out earlier, with the sophisticated ways retailers these days manage their supply chains the odds of something sitting on a shelf more than a few months are pretty low. The last thing they want is to have costly product sitting around and not moving. Just seems like you would spend a lot of time and effort for the "potential" of a little longer life on a battery. I would just buy one if I needed it and be done with it. I hear what you are saying, but just not worth the extra hassle to me for something that I would probably replace once while I owned the car and it has nothing to do with wealth of being a careful consumer. I look at it as one of those things that is just not worth the time and effort for something like that. But that's just me, everyone is different.

Carsy

Alfa, Thanks for you input . JC

ezshift5

........IIRC - upon visiting a nearby MB dealership - the Service Director laid a toll-free number on me for battery replacement planning.

He indicated where to call, what to expect (road service comes to you), cost information - - - - just about the whole enchilada..................

Have I got this correct?


ez sends

reyn3545

Since this is a pretty fresh discussion.... I'll pose a batter question.

About a year ago, we bought a used 2008 C350 for my son. It's been a geat car until a few days ago. It starts and runs fine, but yesterday, all of a sudden, the a/c, power windows, sunroof, and radio just went out. I checked all the fuses, and eventually disconnected and reconnected the battery. That seemed to resolve everything, then today, the A/C quit again. Disconnecting the battery has no effect this time. The compressor does come on, air does blow, and I checked the low pressure A/C line... plenty of Freon. Could this possibly be a failing battery? I wouldn't think so, but I thought I'd ask.

cvx5832

Do you have the factory alarm? Has it been going off randomly?

reyn3545

We do have the factory alarm... it has not gone off.

cvx5832

The alarm going off seems like a common symptom for batteries on their last leg. At least that's what I gathered from Googling when I was getting random alarm triggers in the middle of the night. Changing the battery did in fact fix it. Since you don't have that symptom I'd be inclined to look elsewhere, but I wouldn't be averse to replacing a battery if it were original.

On the BMW boards where I'm more active we can always trace platform-wide issues to squawking on the k-bus, or a bad battery. If the former, it was usually an intermittent contact in the ignition switch.

reyn3545

I just connected my battery charger/tester... it didn't indicate a dead cell, but it did say that it was only about 25% charged. I'll let it charge for a while and see if anything changes. There's no date code punched in the label of the battery, so no way to tell how long it's been in there... probably worth a new one just to be sure.

cvx5832

In my experience that punching is for the date of sale, to be done by the guy selling you the battery. Take the battery out and take a look, there's probably another label for the date of manufacture, or at least was the case in the Duralast and Interstate batteries I pulled out last.

The code will be an alphanumeric sequence, whose format will be manufacturer-specific. You won't be able to decipher the code without Googling it. Which in my mind is intentional, so customers don't pick their batteries and leave the oldest ones on the shelf.

Josh.A.Hussey

If the battery is only at 25% then your problem may reside elsewhere... After charging throw a load tester on it and see if the battery is good. If it passes the load test, you should look elsewhere for the culprit of your escaping current!

reyn3545

The charger has a load tester, and after the charge, it was fine. As it turned out, I think the original charge was fine on the battery, it did start out around 25%, but quickly climbed into the 90's, then topped off. Probably more a function of the charger's circuitry.

I've given up on the skills I learned in my teens, working underneath God only knows how many cars my dad had in his shop.. and booked a trip for this car at the dealership. At least they can give it a once-over, update any overdue EC's, fix that jumpy sunroof that only a dealer can fix, etc.. They've been pretty fair with me in the past with out of warranty situations, but this is the first car I didn't buy from them.... maybe I should take a tube of vaseline with me, just in case.

cvx5832

Hahahaha. Sounds like you'll be fine. It's usually the ladies or less-assertive people that get bullied into a repair.

Josh.A.Hussey

When I have a service appointment with my dealership, I bring TWO bottles...

reyn3545

Update (or lack of one)....

I took the car to our local MB dealer about 2 weeks ago, since then they've tested an re-tested, convinced that it is a heat related situation that only happens in the heat of the day. They cannot recreate the problem in their air conditioned shop, only sitting out on the concrete for several hours. They've replaced the rear SAM, front SAM, and the push button control, with no success. Now it's down to chasing cables & sensors, which doesn't sound cheap by the hour. MB corporate has run out of suggestions. Something tells me the bill could exceed what we paid for the car. They've had it for 2 weeks with no success.

reyn3545

3 weeks and counting... new front & rear SAM, ignition module, headlight switch, a/c push button panel. They've chased all the wiring with no issues, and still if the leave the car in the hot sun for a few hours, it will fail. Most times, it's just the A/C that fails, but sometimes the rear turn signals fail, sometimes you can take the key completely out of the car and the headlights will stay on, sometimes the power windows, sunroof, a/c, gas gauge, will all go out. Somehow, I think I'll need to sell the car to ever get it out of the shop!

Carsy

Can I state the obvious, the modern cars electrics are a PITA to fault find.

Persistence pays off, usually !!