Agm battery keeps discharging

Options
theseeker
theseeker Registered Users Posts: 1
in Solar Beginners Corner #1
I have a 4 powersonic 100ah agm battery. But one of them it just won't keep the charge i will charge it and the battery will say 12.6 volts and then within an hour it is 11.6 volts and keeps falling with nothing connected to it just sitting there. Does this mean my battery is bad? and can it be restored? Thanks for your help
· Share on Twitter

Comments

  • PNjunction
    PNjunction Solar Expert Posts: 762 ✭✭✭
    #2
    Options
    Re: Agm battery keeps discharging

    Most likely it is shot.

    The big question is what is your charging setup? The other three may be heading in the same direction if charging is inadequate. You should be charging PowerSonics at 14.7v absorb, and no more than about 0.3C, or no more than 33a.

    To save time, I'll rattle off a bunch of questions to help narrow things down...

    Are they new or used?

    If new, upon receipt, what was the open-circuit voltage of each of those AGM's? If it was 12.4v or less, that means it had only received an initial factory charge, and has been discharging for about a year in the retail chain - or stored in a hot railcar / warehouse. You may have also received 4 batteries with wildly varying manufacturing dates and the bad one is the first to go from sulfation. Powersonics in good condition should read 12.9v+ ocv with the proper charge.

    Are these batteries connected together in a series / parallel arrangment, and if so, was each one charged individually prior to placing them in their final wiring configuration? If not, the bank may have been badly balanced, and the bad one is now trying to take the rest down.

    You *may* be able to save the bad one somewhat if it hasn't been totally abused / neglected for too long, but I wouldn't count on it. Worth a try however with the proper charging regimen.
    · Share on Twitter

Categories