General Tech Recharging AGM batteries

I know this topic has been beaten to death in many ways. I also know that lots of the info in the web is just misinformation.

I have a group 35 Odyssey battery that is only 3 months old. It's been in my new Tacoma and has been performing flawlessly. Yesterday the battery was completely dead when j went to start it. It measured only 5.2V! I have no idea why it's dead, as far as I can tell everything was off just as usual.

I have a decent charger that says it can charge AGM batteries, but I quickly realized it won't with that low of voltage. After doing some Google-fu I found a quick solution to trick the charger into believing it just needs topped off. I hooked a spare battery up to my Odyssey in parallel then attached the charger. This provides enough voltage to keep the charger running, genius!

Does anyone think that the battery is permanently damaged? I bought it for peace of mind and now I'm worried about trusting it.

I run optima in every thing I can force them in to, and have had great luck bringing them back with a genius charger, my buggy,boat and camp trailer get the charger hooked up a couple hours before use, just to top them off. But as every husband, dad has found, with a little extra help my battery's get run dead often and I have to trick them back in to charging but have always come back to life with in there warranty period, once they get older they seam to just not hold a charge...

AaronPaige said:

I run optima in every thing I can force them in to, and have had great luck bringing them back with a genius charger, my buggy,boat and camp trailer get the charger hooked up a couple hours before use, just to top them off. But as every husband, dad has found, with a little extra help my battery's get run dead often and I have to trick them back in to charging but have always come back to life with in there warranty period, once they get older they seam to just not hold a charge...

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Nice, that's the answer I was hoping for.

Not just a simple, yes I have had good luck and hope you do too... But ya, if your good in a week I wouldn't give it a second thought

you can get chargers now that will Charge: Standard, AGM, and GEL batteries. I've had good luck with those chargers. I've brought back a lot of old batteries with my Shumacher charger. It has an 80 start feature as well.

I have a nice ctek charger built to charge and condition optima style batteries. Was about $100 from Amazon and works great.

the battery is probably very damaged. I bet you can get it to recover but the capacity will be terrible. Change it up and load test it.

Well my little charger trick seems to have worked. I gave it a nice slow charge at 5A and it took nearly 12 hours to do it! It seems to be running good even with the fridge blasting full force. I still have no idea why it drained down so low.

MikeGyver said:

the battery is probably very damaged. I bet you can get it to recover but the capacity will be terrible. Change it up and load test it.

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Is there a special load tester for these batteries or can the autozone guys tell me? Will they be able to tell me if the amp hours will be effected?

Update:

The battery has been plenty strong to use for normal stuff, but voltage dips off with my accessories on very rapidly. I used to get 3 days running my fridge before it turned off, now it's down to about 12 hours!

I called 4-wheel parts to inquire about a warranty and they quickly went in the defense. The guy had me contact Odyssey directly saying that they will trouble shoot my entire electrical system because it's just not likely the battery is at fault. He proceeded to try scaring me out of even following though with the call saying that it takes a long time, they will need all sorts of technical info, etc.

I called the Odyssey customer service, explained my issues, and without pause hesitation the guy says "ok no problem". That's it? That can't be it! All that work up for a quick approval? Yup it was just that easy.

I called back 4-wheel parts explained that Odyssey gave me their approval and it shouldn't be an issue. Their reply was "well, we have to charge it and test it ourselves". Then why the hell make me deal directly with Odyssey!!!??? Ahh!!!

I let them charge it overnight and came back to find it failed their test. That guy was shocked like he fully expected that I was lying to him about it. Atleast I finally got my replacement.