Battery question equalization

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Comments

  • rake1
    rake1 Solar Expert Posts: 173 ✭✭
    Re: Battery question equalization

    Thanks for all your help with this vic I will report back after my return from the camp. Now all I need is some sun on the weekend to do some testing.
  • rake1
    rake1 Solar Expert Posts: 173 ✭✭
    Re: Battery question equalization

    Ok Finally got back to camp and took some measurements,the camp was 3 degrees Celsius when I walked in after two weeks so I have to assume the batteries were the same temp as the camp as they are inside also. My thermometer wasn't working so I couldn't get the actual battery temps. The SG was 12.70 on all cells and the voltage was 14.7 on my batteries. Bulk was set at 14.7, float was 13.8. I have since moved the float to 13.5 as it was a little high. I equalized for two hours at 16.7 volts and 6 amps, batteries were gassing pretty good, SG never really changed still 12.70 to 12.75 (hard to be exact with this hydrometer) at the very most. Did notice a very very small amount of particles floating in the electrolyte which Is probably normal I would think. Any thoughts
  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    Re: Battery question equalization

    Sounds OK--Although, if there were no loads, 14.7 volts sounds high. Was controller going through a quick bulk/absorb cycle at sun up, or is the controller "sticking" in absorb way too long?

    How was the water usage? Hopefully you did not have much (if any noticeable) water usage in two weeks.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    Re: Battery question equalization

    Actually, I take the 14.7 volt comment back..

    -0.005 volts per C per cell * 6 cells * -25 C (below 25C nominal) = 0.75 volt temperature adjustment

    Or ~13.95 volt temperature corrected.

    What do you think the TC was for the SG?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: Battery question equalization
    rake1 wrote: »
    The SG was 12.70 on all cells
    BB. wrote:
    What do you think the TC was for the SG?

    To get the SG up to 12.70 the Temp Compensation must have been off the charts! 12.70 is almost as high as liquid mercury! --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • rake1
    rake1 Solar Expert Posts: 173 ✭✭
    Re: Battery question equalization

    I added 1 full Hydrometer to each cell after equalization was not really down but said what the hell. The TC was about 0.5 as My CC was set for 14.7 and my trimetric meter was showing 15.2 Volts while charging. I dropped my Float to 13.5 as it was set a little high before. The bulk and absorb are now set at 14.8 to try to get a little more into the batteries early in the charge cycle because my CC only hold absorb for one hour before going into Float. I am quite happy with this setup now and it seems to be working great.
    PS does the TC work during equalization?