Did I destroy my battery bank??



  • mcgivormcgivor Solar Expert Posts: 3,601 ✭✭✭✭✭✭
    edited November 2017 #32
    Looking at your temperatures in your first post, 43°C as the battery temperature, that's pretty high, it's said that for every 10° C over 25 °C  one cycle is  equivalent to two, obviously the temperatures were not always that high but it might have played a part in the early demise, keeping them as cool as possible is important. Personally I have to deal with high ambient temperatures sometimes as high as 47°C, keeping the batteries in a room which gets no direct sun, except early mornings helps dramatically, unless the temperature remains high for a week or more then everything becomes hot and the concrete holds the heat late into the night, other than that my battery  temperature is generally 30-35°C throughout the year, today in fact was the first time they've been below 25 in almost 9 months.

    A new 12V LA  battery should have a standing voltage of ~12.7V, they should also be given a commission charge before use, fully charge then EQ, some manufacturers provide this information which may differ, others provide nothing, but it's always a good idea to do so to bring all cells into ballance.

    One option worth considering is LiPo4 lithium, something I've been thinking about, due to their inherentl ability to tolerate higher temperatures, without suffering as much as lead acid, although ideally 25°C is still preferred.

    Good luck with your future battery choice, most learn through mistakes, asking questions when it's  too late, it's really the nature of the game, more common than one may think and often in much less time.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery bank 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah FLA 24V nominal used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • littleharbor2littleharbor2 Solar Expert Posts: 1,569 ✭✭✭✭
    edited November 2017 #33
    sunnyman said:
     I told him that a new battery should read 13.2V and he told me I was talking rubbish!

    A fully charged lead acid battery with no load or charging should measure 12.8 volts

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • softdownsoftdown Solar Expert Posts: 3,494 ✭✭✭✭
    13.2 when minutes off the charger....perhaps. I'd expect closer to 12.8 the next day. ~12.6 - 12.7 within a month or so. Temperature always plays a role as well.

    I doubt that I can find 13.2 volts. I may suggest a compromise. 

    Anything over 12.8 is a surface charge and "evaporates" very quickly.  My .02.
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • sunnymansunnyman Registered Users Posts: 12 ✭✭
    Yes, I was talking about a fully charged battery and in my books that is always off the charger since it starts to loose its charge at once.
    As an example, this is battery no. 6 in its better days and used to settle at 13 to 12.9 after a day. It would take more than 3 days to arrive to 12.8.

  • littleharbor2littleharbor2 Solar Expert Posts: 1,569 ✭✭✭✭
     From the wording of your comment with the battery salesman it seemed you were talking about batteries sitting in the rack waiting to be sold. You will never see 13.2 volts there. What you are seeing in this photo is undissipated surface charge. A battery sitting at 12.8 volts after resting overnight is perfectly normal and not indicative of a problem.

     Granted, not all battery salesmen actually know what they are talking about but from your comments I see nothing indicating your battery salesman is wrong.

    2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old  but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 700 ah @24 volt AGM battery bank. Plenty of Baja Sea of Cortez sunshine.

  • sunnymansunnyman Registered Users Posts: 12 ✭✭
    I understand. Thanks.
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