Batteries newb question

Zakarume
Zakarume Solar Expert Posts: 143 ✭✭
Would it be better to use 4 6v Trojan batteries for a 24v system for use 4 12v batteries in a 24v system


12v batteries http://batteryoutfitters.com/products/rv/. Pro Series

6 v Batteries Trojan t-105
1460 Watts Solar @24v. 675 AH Battery Bank using 12 6v Trojan T-105. 1 Midnite Classic 150. 1500 Watt 24v Samlex Pure Sine Inverter

Comments

  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: Batteries newb question

    I would go with 4 - 6volt batteries, a single string. As I said before, at Battery outfitters in Columbia they will wave the core charge for new installations. Tell them what your doing, and perhaps they will there as well. There is a 'black box' Trojan that has slightly lower specs that run around $80 in the Columbia store. It's there to compete with Costco and Sams club golf cart batteries which sell in the same price range. I would recommend them for your first set.

    As noted before you only have a 5-6% charge rate for this size bank, so be careful you don't draw them down too much. If you were to go with the 12v batteries, I'd only do a single string.

    Core charges on 6v batteries run $20-25 each.
    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.
  • Zakarume
    Zakarume Solar Expert Posts: 143 ✭✭
    Re: Batteries newb question

    I only go to battery outfitters and they are working with me. saved money on batteries bought there already. they will even take my 12v batteries in on trade to get 6v cheaper. roughly $30 extra per 6v


    But also would going with 4 6v batteries my voltages would go up to 24v but AH would stay the same at 225, but

    12v voltage would go up to 24v along with AH

    So would 12v batteries be better in this situation
    1460 Watts Solar @24v. 675 AH Battery Bank using 12 6v Trojan T-105. 1 Midnite Classic 150. 1500 Watt 24v Samlex Pure Sine Inverter
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: Batteries newb question

    I would not think they would last as long, they aren't what I would call true deep cycle, (some of them are but not the proseries and proguide, I would expect them to last longer 5 years or more for the GC and a couple for the marine 12v.

    It doesn't hurt to ask them if the 'new install' will wave the core charge...

    I worry about the charging rate. I still think you have somewhat unrealistic expectations. Worry about chronic undercharging, drawing the battery bank down and not keeping it in the top 20% or so... If you did add another couple panels next year, you might look more seriously at 4 GC batteries. I would say if you don't intend to add more panels shoot for a 12 volt 2 GC battery system...
    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.
  • Zakarume
    Zakarume Solar Expert Posts: 143 ✭✭
    Re: Batteries newb question

    Alot of times i jump ahead of myself without thinking things through first. I am going with the 6V batteries instead. Will trade in the 12v batteries. Battery outfitters will let trade them at the cost i bought them for. Cost for me should be around $200 for the 4 6v batteries. My uncle has a bad 12v battery he will give to me so that will help on a core charge.
    1460 Watts Solar @24v. 675 AH Battery Bank using 12 6v Trojan T-105. 1 Midnite Classic 150. 1500 Watt 24v Samlex Pure Sine Inverter
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: Batteries newb question
    Zakarume wrote: »
    Will trade in the 12v batteries. Battery outfitters will let trade them at the cost i bought them for.

    I wonder what they will do with them... sell them to someone else as new? --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i