As the title reads, the battery did not even make it through the warranty period. I got this battery from Battery Plus as the ultimate expedition battery. These days everyone is out to make a quick buck by branding their low quality product with past quality features. It was a painful 1 week of suspecting everything else in the Jeep, thinking: a two year old AGM battery could not be dead.

 

DEKA AGM battery only cost 155.00....Great battery

 

Can we assume you checked all the usual suspects? Battery terminals; ground points; voltage at battery with engine running; voltage at battery with engine off; etc.

A couple of factors that may shorten the life of an AGM battery in a vehicle:

AGM batteries don't like sustained charging (as on a long drive) at the average vehicle voltage of ≈14.4 volts.
Once charged, they need to be float charged at ≈13.5 volts; less when it's hot in the engine bay.
One poster on a forum cooked his AGM battery. Come to find out, his JK was regularly reaching 14.8 - 15 volts.

AGM batteries don't like high temperatures. Some may require the charging be stopped if its core temp reaches 120°F. Most under-hood temps exceed that, especially in the summer.

As with any other product, one brand of AGM battery may tolerate being in a vehicle better than another brand.

Mine, a Die Hard Platinum Plus, has been in since 2011. But then, the under-hood temperatures in my 2008 JK are significantly reduced due the the installation of an engine driven fan.

 

ive had an oreliiys AGM in the jeep for a few years with no issues but i do have a venting hood and the underhood temps stay fairly low.

 

Orielys Super Start AGM also. Since 2012. No problems including winching. I believe it's a rebranded Deka.

 

$400 ??? They are $225 ($250 - 10% discount for online ordering) on their website: https://www.batteriesplus.com/batter...cca/sli48agmdp

 

Optima Red Top here since late 2010 and she's still kicking even with the heat and frequent long drives. My daily commute was a couple hours for a couple years. It's still at least an hour behind the wheel every day.

 

The X2 battery https://www.batteriesplus.com/batter...cca/sli48agmdp has a 5 year replacement warranty, did they replace it?

 

The problem is the Jeep is on an expedition in Europe...

I checked and triple checked. Th battery does not hold a charge, when professionally tested. I toured most of the southwest US and Mexico dessert, and had a fridge in the trunk.

Prices have come way down since I bought it and i guess the the quality too.

I replaced the battery with a Duracell Advanced, just a normal battery.

 

Don't ever buy batteries of any kind from Batt. Plus, they are the most expensive place to buy batts. My home wireless phone system needed new batts., their batts. were so expensive that I was able to buy a new phone system for what they wanted for batts. I also shop around for a good price, no way that happened here with the 400 dollar battery.