New GC2 battery SG readings ?

verdigo
verdigo Solar Expert Posts: 428 ✭✭
I gave a friend my harbor freight 3 panel set. He bought a couple of "new" GC2 batteries and the SG readings are 12.15 up to 12.25 after a normal automotive charger 10 amp charge. He paid $75 each for these. I don't want to tell him they won't come up if they might. Another friend has a charger that will do 30 amps at the 6 volt setting. Will an EQ help these? I am just wondering how much life they will have if they do come up to say 12.65 if there is some sulfation.

Dennis

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: New GC2 battery SG readings ?

    Let's check what we're talking about first.

    A GC2 will have three cells and therefor three numbers for Specific Gravity (SG). It would read like this: 1.265 1.265 1.265

    Numbers of 12.15 on one and 12.25 on the other sounds like Voltage readings. If they are SG or Voltage they're pretty bad.

    An Automotive charger would not bring the batteries up to the 14.4+ Volts needed for Absorb charging, never mind keeping them there for an hour or two. This could be why they are low. An EQ charge may improve them, but if you can't get that near 15 Volts from the charger it isn't going to happen. Charge current isn't the issue; Voltage is.

    If they have been sitting at <12.6 Volts for any length of time then sulphation will be underway. Depending on how low and how long they may not be recoverable.

    Considering that the big warehouse stores sell GC2's around $85 I don't think he got much of a bargain.
  • verdigo
    verdigo Solar Expert Posts: 428 ✭✭
    Re: New GC2 battery SG readings ?

    They are SG readings. The hydrometer is this one. http://store.snapon.com/Hydrometers-Hydrometer-Battery-P637143.aspx. I'll tell him to take them back if he can.
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: New GC2 battery SG readings ?

    Did you misplace the decimal point in your post then?
     
    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
  • verdigo
    verdigo Solar Expert Posts: 428 ✭✭
    Re: New GC2 battery SG readings ?

    I guess I did. I must have been thinking voltage