You are brave. Several threads on this. I'd replace it ASAP. Our 2011's died all of a sudden. Replaced the other kids a few weeks later.

 

I would go ahead and replace it. Not worth the chance of leaving you stranded. I just replaced mine on my 2014. I reckon that it was 6 years old (from date of battery manufacture) at least. I'm happy with how long it lasted without failing.

 

I still have original AGM in my MY2012. I did capacity check month ago and it had 37Ah, so back it went. (doing "crank" load check is pointless as it is not used to start the engine)

 

2011 with OE 12v battery at 9 yrs 8 months in the Arizona heat. I do carry a small jumper just in case. I don't see the need to toss it until it causes an issue. Why create the waste when it still functions? Tread lightly on this earth.

 

Last time someone I saw a post (different forum) bragging about how old their battery is had to replace it less than a week later after it left them stranded, lol. Hopefully that doesn't happen to either of you.

 

I live in Michigan so the heat is not a problem.
I just tested the battery yesterday and it is good.
I am well aware that lead acid batteries normally do not give much waring before failing, however I have tested thousands of batteries and if you know what to look for during a full cycle test, with this knowledge I can get at least 3 months of warning. The key to this is looking for how sharp and where the knee is in the discharge curve, in a full cycle curve.
Quick battery testers of any type, can't give this kind of warning.

 

I replaced my battery about 4/5 months after first indication of a problem (compass disappeared). I happened to have the cargo cover up (can't remember why) and happened to measure voltage (11.9V). Never had any other problems but Canadian Tire was having a pre Xmas sale plus a $50 card promotion so bought the battery and returned the old one for a core charge. I don't need the compass (I know which direction I'm headed) but it was 6 years old, I typically get 7 years out of a lead acid on my other cars, so wasn't worth waiting till I needed it most. Temps here are the best you can get for a battery (not too warm and not too cold). A battery can have a wide range of life depending on a variety of factors not the least of which is the manufacturing of that particular unit. If it's getting on and you notice something off, replace it while you can, especially if a good deal is out there, waiting to be had.

 

with these cars its almost like the gemlin curve
starts out doing weird things and then ends up leaving you stranded on the side of the road.

 

Definitely not always the case. My Volt ran perfectly, not a single glitch or flicker that got my attention and I monitor everything as I'm OCD like a crazy person. Then one day it was so dead not a single light turned on.

 

Aside: Here is a drop that happened in my Tesla X a few days ago. AGM deep-cycle lead-acid.

View attachment 171267

 

Aside: Here is a drop that happened in my Tesla X a few days ago. AGM deep-cycle lead-acid.

View attachment 171267

pictures of my 'ghost in the machine'
cool

 

In my opinion, you're flirting with an event that could ruin your day and be expensive to resolve.

In lieu of complete AGM replacement, you should have some sort of means to power the 12V systems back up should the AGM just instantaneously die on you. I have been contemplating carrying one of my copious 18V powertool batteries with a buckpuck (they're 10$...) outputting 13V around with me to essentially jump the car via the connectors in the engine bay, should it be required.

This car just needs a couple Volts to start up whereas most other vehicles need the Amps to start. If you have ever seen a Volt with a dead 12V, it's nothing like most other cars; when my MY12 died on me about 6 months ago, it was super dead, like no indication or lights at all. Then there is also the aspect that happens when the computer's reference voltage drops too low during operation. The car literally died during operation. That was baffling to try to resolve but it turns out when I had installed the new AGM, I had a poor connection on the battery and it worked itself loose.

 

My 2013 Volt has its original 12V AGM battery in the temperate San Francisco Bay Area, and I carry a lithium ion battery boost just in case. It's an experiment, having bought a replacement AGM Duracell battery from Batteries Plus Bulbs for $138 last year.

 

How'd you get it for that low a price may I ask? Almost all the ones I've looked at are at least $200. I've been looking into replacing mine because it couldn't even jump start my sister's Hyundai without turning on the car. It's the original to my 2013 Volt, so I'm sure it's on its way out soon.

 

I did some googling for an AGM 12V battery, and one of the sites that popped up was Batteries Plus Bulbs. The price of the battery was $140 less a 10% discount and plus a $12 core charge. 'Not sure where I picked up the 10% discount code. I'm still looking for someone's discarded battery to recover the $12.

 

I bought a Duracell AGM battery from Sam's Club. The regular price is $145 but they often put it on sale for $125, plus a core charge. It is exactly identical to the ACDelco OEM battery it replaced.

 

2011 Volt, delivered new in March, 2011. Still on factory 12 volt battery. I have a lithium ion jump pack just in case.

 

I would run my computer UPS with my old Volt 12 v battery BUT by the time I have 2 batteries ( UPS uses 24 volts ) my first battery would be 14 years old

point is we are not testing our replaced battery that are removed for a just in case condition.

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batteries plus may give a 10 % on internet orders with a self pickup -

 

Changed the 12V in my 2013 Volt from the dealership two days ago. Original 12V lasted almost 8 years. Cost of battery $189 without tax from Findlay Chevrolet. $40 to install. Took them 2.5 hours to finally install it.

 

Do I have the record? Just replaced the original AC Delco factory 12v battery after 11 or 12 years. This is a 2013 that I bought new in late 2012 and it's 2024 now.

 

I think you may have the record
something something chicken dinner

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I chickened out when I saw 11.9 volt on a winter day while applying the parking brakes
still on my second batery.

 

I am still on the OEM 12v in my 2013 delivered ELR. Load tested within 30CCA last time I checked. I am in the shop today with it, I'll check again if I remember.