AGM DieHard battery won't charge past 12.7 volts?

[rockandroll]

After using my new DieHard AGM battery for a week in the camper, I've noticed that no matter how long I charge it the voltage won't go higher than 12.7 volts. I've charged it with my DC-DC staged charger and the stock converter both of which put voltage numbers in excess of 13.5 volts into the battery, but it will always fall down to 12.7 before use.

Is my battery toasted? It seems to work fine, but I'm concerned that I'm not getting the full storage capabilities of this expensive battery. I also purchased it more than 3 months ago, so it may be out of warranty.

Here's the battery: http://www.mysears.com/DieHard-Marine-Battery-Platinum-PM-1-Group-Size-31M-with-exchange-reviews

 

[alexrex20]

that's normal. and your battery is covered for 36 months. it says right on the website you linked to.

 

[Gary Franks]

I don't think that 12.7 is bad. A 100% State of Charge is 12.6 to 12.8.

The battery voltage should be measured after the battery has been at rest for more than 4 hours (after being disconnected from any charger or load). Don't forget that temperature may affect your reading also.

I have Lifeline AGM batteries in my motorhome and boat and a Die-Hard Marine AGM in my Jeep.

 

[d1sc0ver]

A 100% charge on a 12v battery is normally 12.7 volts.

See section 6 at this link:
http://www.batterystuff.com/tutorial_battery.html#3

 

[rockandroll]

Thanks for the help and good news. Not sure how I got it in kmy mind that it should be greater than 12.7v.

Back to the road. Mexico here we come.

 

[Terrainist]

I bought one of those, 3 year warrantee as stated. And if I remember correctly it's prorated after that. Mr. Sears guy that sold it to me said, "This is the last battery you will ever buy." Cool with me.

 

[kb7our]

Does anyone know at what point one is entitled to a replacement battery? What is the criteria?

 

[Antichrist]

I would assume when it fails to hold a charge, or when it fails a load test.
Or if it physically fails, like a split case or something.

 

[Terrainist]

Do your own homework, but.. I think I was told full replacement first three years, prorated after that. Probably wasn't what you wanted to know. Otherwise, what he said.

Sort of odd when a manufacturer does something like that, full replacement. All someone has to do is cook their battery every two and a half years and go get a new one. People used to do the same thing with that sort of warrantee on tires. Run them till they are at about 50%, over inflate them and run them till they separate, put the air pressure back to normal and go get however many new ones, do it again.

Makes me think that there is only about 10 bucks into the battery or tires, and there is no way the purchaser could catch up to the original purchase price. Or someone miscalculated. And miscalculations have happened before... I remember some sort of national chain garage offering lifetime oil changes for something like $300 within the past decade or two. They took it in the shorts on that one. They are still waiting for people to die so they don't have to change their oil.

 

[alexrex20]

anyway...

 

[Terrainist]

Get a life dude. Surely you have better things to do than run around these boards and post rude crap. Or maybe you don't.

 

[alexrex20]

Get a life dude. Surely you have better things to do than run around these boards and post rude crap. Or maybe you don't.

well, it's about as useful as your posts.

 

[Antichrist]

I'm thinking a post was deleted.
Trust me to miss the drama. LOL

 

[pods8]

Sort of odd when a manufacturer does something like that, full replacement. All someone has to do is cook their battery every two and a half years and go get a new one.

Most of these warranties don't refresh with the replacement, they stick to the original purchase date. Thus if there is a 3 year warranty and the batteries die after 1.5 years, you'll end up getting 1 free replacement but it doesn't continue forever, when that second one dies just after 3 years you get nothing. They're only guaranteeing you 3 years of working battery with the original purchase not that each battery will last 3 years specifically. I'm not saying they won't either, just pointing out how those types of warranties work.

 

[Terrainist]

That make more sense. They'd could be on the hook for someone's battery, plausibly for life if they didn't. I'll have to call them up, see how they do it.