Oversized Battery Bank - Is that a Problem?????

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Comments

  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    I must have missed something here.... When did you change from AGM to FLA batteries???
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • jcheil
    jcheil Solar Expert Posts: 722 ✭✭✭
    I have found for MY L16RE-B's, that I bulk/absorb at 59.6v and absorb for about 6 hours.  At that point, my end amps going into the batteries is around 2-3 (per bank) and I am usually just at the 1.270+ range for SG. Now, I have a lot bigger WH battery bank than you do but I would think it would all be relative.  Anything below 59.6 (for me) and I found that they would not get up to the proper levels (or gas enough) even given that we have PLENTY of sunny hours in the day down here in Florida (not to mention I have 11kw of solar too).

    With my 3 banks (24 batteries) I use about 1 to 1-1/2 gallons of water every 4-6 weeks.

    Off-Grid in Central Florida since 2005, Full-Time since June 2014 | 12 X Sovello 205w panels, 9 X ToPoint 220w panels, 36x ToPoint 225w panels (12,525 watts total) | Custom built single-axis ground mounts | Complete FP2 Outback System: 3 x FM80, 2 x VFX3648, X240 Transformer, FLEXnet-DC, Mate-3, Hub-10, FW500 AC/DC | 24 x Trojan L16RE-B Batteries 1110ah @ 48v | Honda EU7000is Generator and a pile of "other" Generators | Home-Made PVC solar hot water collector | Custom data logging software http://www.somewhatcrookedcamp.com/monitormate.html
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,894 ✭✭✭✭✭✭
    Batteries in cold environments also have less apparent capacity. It does come back as the ambient increases to where they are happiest, about the same temperature that humans like.
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • Dan-A-Canuck
    Dan-A-Canuck Registered Users Posts: 9 ✭✭
    Hey everyone, thanks for all the great info.  I think I've pieced it together and figured out why I'm not using any water.  Simply  put, I was under charging my batteries by just a little.  The default time for absorb on my Outback was one hour... that was not enough.  I've bumped it to two and the SG is very close to spec, I'll fine tune that next summer when the nice weather is back.  My batteries never really boiled for any length of time, they do at two hours.  For now, we are a breath away from solid water.  My last trip will probably be this weekend just to see how everything is at the camp.  Hopefully, I haven't damaged the batteries with the undercharge (it was probably +90% all the time).  Again, thanks for all your help.  BTW about capacity in cold climates for my southern friends, the batteries may last a very long time but they certainly SUCK as December 21 and -20 is on the horizon. I have half the capacity and it takes twice as long to charge this time of year.
  • Photowhit
    Photowhit Solar Expert Posts: 6,006 ✭✭✭✭✭
    Batteries also have less capacity when cold!
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.