L16 battery question

shockman
shockman Solar Expert Posts: 113 ✭✭
So I let by battery bank discharge to a DEAD state and acid did get below plates, long story! I have since charged and to the best of my ability equalized. SG did come up to varing levels. So realizing that I have probably lost the good remaining life of these 51/2 yr old batts, I have one dead cell that will not give me a reading on SG. I have removed it and one other from bank. My question is can that cell be brought back to life?
4x240w panels,Classic 150 CC, 4x380AHR L16's, antique Trace 12V inverter

Comments

  • shockman
    shockman Solar Expert Posts: 113 ✭✭
    Okay, have not been on here for a long time and wondering where system details that used to be below went LOL
    4x240w panels,Classic 150 CC, 4x380AHR L16's, antique Trace 12V inverter
  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    The battery is probably a goner, but you might want to do a search on the forum for "battery water treatment" thread.  IIRC, a member here ( @mcgivor ?) had some success recovering a sulfated battery with distilled water.
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • mcnutt13579
    mcnutt13579 Registered Users Posts: 111 ✭✭✭
    5 1/2 years on L16s, they were already gone.
  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    Mine are coming up for 5yrs, and I'm hoping they're only middle-aged! :smiley:
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    You can add/edit your signature here:

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    In my humble experience, once lead acid batteries get more than a year or two on them--If they are taken "dead", the can recover but tend to be unreliable and can "die" again in a few days or a few weeks (my experience with automotive batteries).

    If you are up in BC Canada, and the batteries have been kept on the cool side (say off grid cabin and get below freezing in winter), they can last you quite a few years longer than folks that live in warm areas.

    Of course, batteries with low specific gravity (discharged) will freeze in cold weather and (flooded cell batteries) probably crack the case(s).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • shockman
    shockman Solar Expert Posts: 113 ✭✭
    edited November 2018 #7
    Thanks for replies. Batteries are in a sort-of root cellar under house, so temps are pretty consistent between 10C in winter and 20C in summer. Today with 2 batts in system I charged with Iota and morning sun to float stage then got 3hrs of Eq. Before leaving sg was 1,185 on one batt and only 1.165 on other ?? Guessing that week one will drag other one down? So I guess I'm off to the battery guy to drop some big bucks LOL or should that be COL (crying out load). Now I need to know from above comment on L16's, what should I be buying. When I bought the present ones I expected 10yrs. To be fair to existing ones I like to think they have been well charged and filled properly until a couple of months ago when I was not around to babysit and left electric fridge on. So would Bill's experience tell us that if not allowed such abuse I may have gotten 10yrs?? 
    make those eq #'s 1.285 & 1.265
    4x240w panels,Classic 150 CC, 4x380AHR L16's, antique Trace 12V inverter
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Exposing the plates is another issue that can kill the battery bank pretty quickly...

    I am guessing that you would have lost some of the batteries by 7 years... And had a few that lasted >8 years. The colder they are, the longer (aging life) they would have. (every 10C drop below ~25C, they age 1/2 as fast--Of course, the slower aging would only be during winter--Your none-winter temperatures are pretty mild).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • shockman
    shockman Solar Expert Posts: 113 ✭✭
    So is there a best bang for the buck? 6 golf cart 240ahr or 4 380ahr L16's or are you pretty much buying by the pound? And what about AGM, my experience with AGM(Optima) and various wheel chair 12v is that they take far more neglect as far as charging??
    4x240w panels,Classic 150 CC, 4x380AHR L16's, antique Trace 12V inverter
  • mcnutt13579
    mcnutt13579 Registered Users Posts: 111 ✭✭✭
    Go to Deka's web site and pull up all their spec sheets for AGM, gel, L16, and flooded steel tray (fork lift style/industrial) side by side.

    Check the DoD (Depth of Discharge) vs expected cycles.

    You will find the steel tray to last somewhere on the order of 3x the L16s for the same DoD.  And experience seems to indicate even more.

    Steel tray batteries are the way to go if you don't mind watering.  Yes they are big and heavy.  But you only have to do it once (or much less often).  You can also get one string any size you want, for the most part.
  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    edited November 2018 #11
    Estragon said:
    The battery is probably a goner, but you might want to do a search on the forum for "battery water treatment" thread.  IIRC, a member here ( @mcgivor ?) had some success recovering a sulfated battery with distilled water.
    Been almost 2 years since I did the water treatment, the battery, in particular the cell is doing fine, it kept the battery in service in a lesser role of water pumping, perhaps using 40-60 Ah per day on a 260 AH 24V nominal system, which it handles fine, the SG has been steady matching it's team mates within a couple of points
    To be honest it's a time consuming process, if the resources are available with nothing to loose I would recommend it, here is the link to the thread, should one be interested https://forum.solar-electric.com/discussion/351467/water-treatment-for-over-sulfation#latest
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • shockman
    shockman Solar Expert Posts: 113 ✭✭
    Thank you! will check the thread out,

    4x240w panels,Classic 150 CC, 4x380AHR L16's, antique Trace 12V inverter
  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    shockman said:
    So is there a best bang for the buck? 6 golf cart 240ahr or 4 380ahr L16's or are you pretty much buying by the pound? And what about AGM, my experience with AGM(Optima) and various wheel chair 12v is that they take far more neglect as far as charging??
    Personally, I'd go for a size that gives me the capacity I want in a single or at most two series strings.  IMHO, AGMs are no less sensitive to charging neglect than flooded, except for the watering part.  Flooded probably tend to handle overcharging better, and both will lose capacity with chronic undercharging.  AGMs tend to have lower self-discharge, which could be a factor in some applications (eg seasonal cabin with no float power available).
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter