I have two XS Power D3400 batteries that I've been running for the past two years. Recently my alternator went out which caused them to drain completely and sit in my truck dead for over a month. They have drained on me in the past before too when I went out of town for 2 months.
I just took them out and charged them both up. Battery 1 was all the way down to 2.33v and Battery 2 was down to 4.91v. It took 3 days for each one to charge above 12.6, but now that I've disconnected the charger they are sitting way below 12.6v each after just 3 days.
Battery 1 is at 11.2v, and Battery 2 is at 12.3v. They have been sitting in my garage with nothing connected to them. No power draw at all.
I know they're supposed to stay at 12.6v or above. So does this mean they're done for since they won't maintain proper voltage?
One of them also has a bulge in the top of the case if that makes any difference. That's the one that's sitting at 12.3v on the right in the photos. Couldn't really capture it in the photo..
This is the batt with the bulged top, hard to see in the photo though..
Battery 1 charge notes
Battery 2 charge notes
This is the charger I've been using
battery #1 serial number is worn off unfortunately
Bulged battery #2 serial number