Odyssey AGM battery- complete failure?

[Bonnewagon]

My other car ( '05 Cobalt) is stuck at my daughter's house 30 miles away. Last night I went to start it and all seemed well until I turned the key. Then everything shut down and the electrical system was so dead even the dash light was dim. I jumped it for a half hour and that did nothing. After all that all I got was one measly "click" out of the starter and then dead again. I am using an Odyssey AGM battery mounted in the trunk. It's probably about 7 years old. Until now it was trouble free. So has anyone ever heard of these AGM batteries failing so suddenly? I'm actually hoping that is all it is- otherwise it's something else and I'm in a world of hurt.

 

[Kwik_Cutty88]

Its definetly possilble. I think my 8 year old optima has a weak cell and it will just die suddenly too. So its possible yours could have a totally dead cell. Honestly i wouldnt be too upset though, even though AGM's are expensive, 7 year battery life is damn good.

EDIT: do you know anyone with a battery load tester? That would be a really quick indication.

 

[Bonnewagon]

Hoo boy, lucky day. It was the battery. Yes, I have a carbon pile load tester. That's the first thing I did, was hook that up. It showed over 12 volts- until I put a load on it. Then it dropped to zero! Weird. The interior lights worked, dash was dim, headlights worked, but dim. So that's that. Total failure out of the blue. I had an old Optima laying around. I charged that up and took it with me. Bingo- fired right up. Now, this battery is in the trunk with the spare under a cover. Does an Optima give off gas? It says non-spillabe, so I guess it's an AGM too? The stock battery that is supposed to go there (hard to find) has a tube that vents the gas out the floor. I just figured the non-gassing Odyssey was an easy way out. And it was- until last night. But I found on an aviation site that they use Odyssey AGMs all the time because they can't spill acid no matter the attitude of the aircraft. Some guys posted accounts of total out of the blue failure. So I guess it's not so rare.

 

[Kwik_Cutty88]

Awesome! Optimas do not "gas." They are a true AGM with no acid. You can tip them upside down, and nothing will happen. You can also break the case open or cut it in half and nothing will happen. That is why they are commonly used in racing. I think its definitely worth it to replace with another AGM. Odyssey's are very good, as well as Optima and XS Power. I think they are on the pricey side, but well worth it. I've heard of AGM's failing out of the blue as well (after a few years), I'm not sure why other than a bad cell or two inside.

 

[565bbchevy]

I have had the same staggered cell deep cycle Optima in the trunk of my Monte for probably going on 15 years, the advantage mine has is when not in use it is plugged into the maintainer that I have hardwired in the trunk.
I never expected it to last this long and it still fires up all those cubic inches with ease but it will be put to the test next year when the high compression engine goes in.

 

[Bonnewagon]

Well this is an everyday use car- never gets a rest- and driven by a female. If that doesn't constitute "severe duty", I don't know what does. I am glad the Optima doesn't gas, now I can leave it there for a while as I search for a replacement. This particular Optima suffered many total discharges in a vehicle that had a parasitic drain. We think it was the old Onstar system that is no longer supported. No one told the vehicle and it keeps searching to no avail while killing the battery. I had it in my old TA and it seemed to hold a charge pretty good. The GM parts sites don't even list the original battery. I suspect there is a TSB somewhere saying- " We give up- find something else to use".

 

[Turboelky]

I've had good success with odyssey group 78 batteries, actually brought one back from 9 volts today. I tried a Bosh AGM and it started to give me issues on the exact 4 year purchase warranty month....last month. I've used optima but went through a couple until I got a good one under warranty. Their red tops are junk, yellow tops seem to be a better battery.