Costco GC2 6V Battery, charge specs and Peukert

nsaspook
nsaspook Solar Expert Posts: 396 ✭✭✭
I'm using some of my tax return to upgrade the hobby PV system here with more panels and new batteries. I picked up two of the Costco GC2 225Ah batteries for a series 12V bank. Would just using the Trojan T-105 parameters be ok?

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert

    Good enough for government work. :p
    It wouldn't surprise me to find the Costco units are made by Trojan. Not that many battery manufacturers in the world, you know. Since the internal chemistry and technology is fairly consistent for FLA's any battery with the same Voltage & Amp hour rating is likely to be close enough on other specs as to not matter. Any two of the exact same make/model batteries are likely to have as much variance.
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert
    Since the internal chemistry and technology is fairly consistent for FLA's any battery with the same Voltage & Amp hour rating is likely to be close enough on other specs as to not matter. Any two of the exact same make/model batteries are likely to have as much variance.

    I would say this is true for most any batteries except Trojan!

    Trojan specifically DOES NOT recomend doing any equalizing unless the specific Gravity (SG) of the cells is well out of balance. Other manufacturers recomend doing equalizing evry month to 6 months.

    I suspect it has something to do with their seprator sheeting, they brag on...
    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.
  • solarvic
    solarvic Solar Expert Posts: 1,071 ✭✭✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert

    Nsaspok. How much do these batterys cost at cosco? The closest cosco for me is a little over 50 miles. solarvic
  • machineman
    machineman Solar Expert Posts: 129 ✭✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert

    I'm running 8 of the Costco GC2 6V Golf batterys for over a year now. Mine look like these red top US-2200 Batterys except with single caps. I was unable to find any detailed charging specs.

    http://www.usbattery.com/usb_golf_p1.html

    Off Grid Cabin, 24V 440ah 6V GC battery bank, Xantrex MPPT60-150 CC, Magnum MS4024 inverter-charger, >1200w Solar bank

  • nsaspook
    nsaspook Solar Expert Posts: 396 ✭✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert
    solarvic wrote: »
    Nsaspok. How much do these batterys cost at cosco? The closest cosco for me is a little over 50 miles. solarvic

    I paid 79$ each with a 9 dollar core charge. I had some old C&D AGM UPS batteries for cores. Lots of RVers use them here so they had plenty at the local store. Don't know who the OEM is but the ones they have were all black with white filler caps.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Costco GC2 6V Battery, charge specs and Peukert

    Call ahead before you go for golf cart batteries... At least in our area, Costco does not carry them at all locations.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • solarvic
    solarvic Solar Expert Posts: 1,071 ✭✭✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert
    nsaspook wrote: »
    I paid 79$ each with a 9 dollar core charge. I had some old C&D AGM UPS batteries for cores. Lots of RVers use them here so they had plenty at the local store. Don't know who the OEM is but the ones they have were all black with white filler caps.
    Thank you for the price. Battery price reasonable but core charge isn,t. I called a couple places about l-16 size batterys and they didn,t even want the old ones. Most they would give is $2.00 each for old batterys. :Dsolarvic:D
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Costco GC2 6V Battery, charge specs and Peukert

    Check your local Costco... Core charges vary by state law.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert

    FWIW- Sams club has similarly priced golf cart batteries, Mine will get replaced this year, they turned 5 years old in Novemeber.

    When I purchased mine, the local Sams Club's batteries were more than 2 months old on the shelf and they did not have 4 from the same month of manufacture. I think it's worth getting fresh batteries and batteries age together...
    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.
  • nsaspook
    nsaspook Solar Expert Posts: 396 ✭✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert

    The local Costco had man dates of 3/11 on the set I got.

    http://wikimapia.org/#lat=45.559632&lon=-122.524745&z=17&l=0&m=b
  • nsaspook
    nsaspook Solar Expert Posts: 396 ✭✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert

    Data from Johnson Controls:
    6Volt

    GC2 Enertec product Blk/Blk: SAM'S CLUB/Costco
    Amp-Hour at the 20 hour rate: 225Ah
    Minutes at 75 amps: 110 minutes
    Minutes at 25 amps: 447 minutes

    The Peukert factor is about 1.26

    http://www.smartgauge.co.uk/peukert_depth.html
  • warren
    warren Registered Users Posts: 21
    Re: Costco GC2 6V Battery, charge specs and Peukert

    I'm trying to check stock at various costco stores but I'm not getting any hits for these batteries. Does anyone know what the actual costco part # is or what search words on their sites will locate them?

    Thanks
  • Seven
    Seven Solar Expert Posts: 292 ✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert
    warren wrote: »
    I'm trying to check stock at various costco stores but I'm not getting any hits for these batteries. Does anyone know what the actual costco part # is or what search words on their sites will locate them?

    Thanks

    You usually won't find batteries on the site. Sometimes you can if you pick a specific store inventory, but because they don't ship them(HAZMAT) you are not likely to see them on the net. The telephone can be your friend.
  • System2
    System2 Posts: 6,290 admin
    Re: Costco GC2 6V Battery, charge specs and Peukert

    I just bought 2 of these at Sams club. The receipt says ( 1194 ENRGZR GC2 )
    $72.63 + 9.00 core deposit.
    I also have 2 US batteries 2200's. Can I use the 2 sets of 2 in a series/parallel bank. The amp hrs vary 220 on the GC2 and 232 on the US 2200. That would give me 12v and 252ahrs.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert

    it's generally not a good idea to try to mix and match batteries. they should be the same make and model with reasonably the same date within about a year or so, but that depends too on how pressed the batteries were/are as one hard pressed won't match another just float charged even with the same date code.
  • System2
    System2 Posts: 6,290 admin
    Re: Costco GC2 6V Battery, charge specs and Peukert

    Thanks for the response niel.
    Is the "not a good idea" a dangerous idea or that one set will work the other set harder??
  • Seven
    Seven Solar Expert Posts: 292 ✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert

    You will have issues because the batteries will charge and drain at different levels. They will never be equal and they may create issues for your other system components.

    Think about driving your car with different sized tires at each corner. The car will drive, but it won't handle correctly, your speedometer will be off and you will wear the tires out quickly because the alignment is off. That kind of stuff.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Costco GC2 6V Battery, charge specs and Peukert

    Hmmm... Yes, it is really a good idea to avoid mixing battery ages/brands.

    But, we even here had somebody here that mixed AGM with Flooded Cell--And the bank, surprisingly worked OK (at least it did not die within weeks).

    For a small, inexpensive bank, if you keep track of how well it works--why not. It will not catch fire. At worse, some batteries may stop contributing to bank charging/discharging and need to be replaced or removed (in the case of open/shorted cells).

    Also, if you mix High Capacity/Low Capacity cells/batteries in series--You need to treat the string as the lowest capacity cells (say you have 100 AH and 150 AH cells in series, you need to assume a maximum of 100 AH for that string).

    Also, with the availability of a pretty cheap DC Current Clamp Meter (~$60)--It makes it very easy to check parallel connections and see that each string (battery) is contributing an appropriate amount of current when discharging (and taking an appropriate amount of current when charging--look for shorted and open cells).

    I would still not recommend paralleling 50 AH and 250 AH strings together (try to keep roughly equal AH capacity for parallel strings and avoid going over 2x difference between high/low string).

    In the end, if you can get roughly equal batteries (similar chemistry and AH rating) and make a bank out of them for little money--Why not... Just don't plan on drawing it too deeply (old/mismatched batteries will probably not like real deep cycling and weak cells may fail). Try to keep above 50% discharge cycling(?).

    Worst that happens, you recycle the first bank and start again with a matched set.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Costco GC2 6V Battery, charge specs and Peukert

    no danger to you. just not good for the lives of the batteries as the good will generally be dragged down to the level of the bad.
  • System2
    System2 Posts: 6,290 admin
    Re: Costco GC2 6V Battery, charge specs and Peukert

    Thanks everyone for your input.