Battery upgrade...what size?

msgieser
msgieser Registered Users Posts: 24 ✭✭
In upgrading my batteries I'm looking at two options. Any comments are appreciated!

1. Trojan T105RE's. These 6 volt batteries are 225 amp and cost about $175 each. In my 12 volts system, 8 of them would give me 900 amps and cost $1400.00

2. Trojan L16RE's. These 6 volt batteries are 370 amp and cost $350 each. In my 12 volt system 4 of them would give me 740 amps and cost $1400.00

The big question I have is which is best? Option #2, with the L16's would give me 160 less amps for the same price. But what am I missing? I realize the L16's are a lot bigger/stronger but does anyone know if they have better "amp utilization"? What about recovery? I have experience with the T105's but know nothing about the L16's. Is it worth the loss of 160 amps if going to the larger battery? HELP?

Comments

  • wellbuilt
    wellbuilt Solar Expert Posts: 763 ✭✭✭✭
    I have met a few guys that are off grin in nys and use SAMs club go 215 I think . 
    They are running 24 volt sys.
     One guy has 4 six volts for frig and 8 6 volts for house hold stuff with different inverters and different chargers . 
     The other guy used 8 gc230s 1 8 battery 6 volt at 24 volts  for every thing only has 1000 watts of solar and runs a genarator for a hrs or so every day . His battery's are 8 years old  but need to be changed now.
     Seems  good to me , really don't think you need to spend a lot of money on battery's  SAMs gas are 89 bucks each .


    Out back  flex power one  with out back 3648 inverter fm80 charge controler  flex net  mate 16 gc215 battery’s 4425 Watts solar .
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    At twice the price of a sams club golf cart battery, the trojan t105 does not look like a good value to me.

    More important though is the number of parallel strings of batteries.  The smaller batteries require 4 parallel strings to get the capacity you need.  The L-16 would have only two parallel strings.  The fewer the better.

    Why not buy six 2-volt batteries and have just a single string?

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Welcome back msgieser,

    Are you still committed to the 12 volt battery bank? ~800 AH is about the largest AH battery bank I would suggest before going up to the next voltage (12 to 24 to 48 volt bank).

    Also, I am not a fan of paralleling battery strings if it can be avoided. 1x (for me) is ideal. 3x parallel strings is about the maximum I would suggest unless you have no other choice.

    You have been using battery systems for quite awhile now--Are you getting tired of checking water levels and battery connections? Have you had any issues with debugging parallel batteries, slow failures (one cell battery fails, then a few months later, a second fails, etc.).

    If you look for 2 volt cells, be a bit careful. At least one of the Trojans is actually just a 3 cell battery with the cells wired in parallel instead of series (still three cells to check/water/etc.).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    BB. said:
    If you look for 2 volt cells, be a bit careful. At least one of the Trojans is actually just a 3 cell battery with the cells wired in parallel instead of series (still three cells to check/water/etc.).
    Trojan makes a true 2 volt battery (one big cell) in their industrial line.  The one you are referring to is their RE line.  They use their L16 case and put the three cells in parallel. 

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • DConlyGuy
    DConlyGuy Registered Users Posts: 80 ✭✭
    im kinda partial to crown 6 volt battery, my cr 235 are pretty close to  the t105 re,  and my cr 235 only cost me 105 each at the local battery shop.
    600 watts of solar panels,Epever 30 mppt , 2 PWHR12500W4FR battery's in 24 volt setup
  • oil pan 4
    oil pan 4 Solar Expert Posts: 767 ✭✭✭✭
    Do what ever gets you the most AH for the fewest $.

    Solar hybrid gasoline generator, 7kw gas, 180 watts of solar, Morningstar 15 amp MPPT, group 31 AGM, 900 watt kisae inverter.

    Solar roof top GMC suburban, a normal 3/4 ton suburban with 180 watts of panels on the roof and 10 amp genasun MPPT, 2000w samlex pure sine wave inverter, 12v gast and ARB air compressors.

  • bill von novak
    bill von novak Solar Expert Posts: 891 ✭✭✭✭

    oil pan 4 said:
    Do what ever gets you the most AH for the fewest $.
    While keeping the number of strings as low as possible - and still getting decent batteries.