Buying a battery that has been stored for more than 8 months

Nabiru3Nabiru3 Posts: 13Registered Users ✭✭
Buying a battery that has been stored for more than 8 months, we all know of something called self-discharge and it happens inevitably with time. but what happens if the battery was stored for a long time and was discharged to less than 50% of its rated 20C capacity and the buyer didn't even bother to recharge the battery once awhile to let the battery stay above the threshold level ?  


  • mcgivormcgivor Posts: 2,211Solar Expert ✭✭✭✭✭
    edited July 30 #2
    When a battery has been in storage for an extended period of time dropping capacity to levels as low as 50%, the battery should be fully charged then equalized, if flooded  to restore the capacity, using without doing so will eventually lead to permanent damage.Never equalize an AGM, unless the manufacturer specifies a boost charge.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery bank 

  • jonrjonr Posts: 1,077Solar Expert ✭✭✭✭
    edited July 30 #3
    You get some some permanent sulfation.   You could measure AH capacity and/or SG  to get an idea how much.
  • BB.BB. Posts: 27,902Super Moderators, Administrators admin
    The battery is probably no good... 

    Trying to recharge it and test, perhaps you can get some use out of it...

    However, my experience with lead acid batteries that have been taken to dead (typical car battery), is that even if you get them working--They can fail a few days to weeks later (work OK for a bit, then the next time you use it, dead).

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
Sign In or Register to comment.