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thriftydutch's avatar
thriftydutch
Explorer
May 18, 2016

Batteries-Don't understand

Okay I have read the article on The 12volt side of life but don't understand. I have installed a new PD 9245 Converter/charger but after leaving my batteries for a few hours it reads 12.2 volts. Is it not supposed to read 12.6v when fully charged. These are 12 volt Costco deep cycle batteries but one is older than the other but I feel I have abused them. But before I rush out and buy 2 6volt batteries i want to make sure these are no good.
All I really run on the house batteries are Led light and a 12v fridge.
Class B

16 Replies

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  • time2roll's avatar
    time2roll
    Nomad
    May 18, 2016
    Charge them again 4 hours with the PD9245. Then disconnect the battery cables to prevent any draw and to separate the batteries. I think one may hold 12.6 while the other goes below 12.0 volts. Or both could be bad. Probably best to get both new anyway.

    Voltage should steadily climb to 13.6 to 14.4 while charging.
  • Shadow_Catcher's avatar
    Shadow_Catcher
    Explorer
    May 18, 2016
    It is a basic that batteries should be the same age. when connected they default to the weaker of the two. Try separating and charging independently.
    Battery Faq
  • thriftydutch's avatar
    thriftydutch
    Explorer
    May 18, 2016
    When it is charging it is 13.6. When I take the charge off it reads 12.26. When I turn on the fridge it drops down to 11.97

    I do boon dock so I need 2 batteries.
  • Big_Katuna's avatar
    Big_Katuna
    Explorer II
    May 18, 2016
    What does it read while charging? And when you measured the 12.2 are you sure there isnt a draw? Doesn't take much of a load to take it to 12.2.

    Get a specific gravity device and take readings of every cell. It will tell you if the battery is taking a charge.

    Also how old are they?
  • 2oldman's avatar
    2oldman
    Explorer II
    May 18, 2016
    12.2 right after a full charge is not good. If you don't dry camp you really only need one 12v battery.

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