Charging Lead Acid Batteries

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  • barry wilkins
    Senior Member
    • Aug 2009
    • 172
    #1

    Charging Lead Acid Batteries

    If you try to charge 2 batteries in parallel from one source of power, the battery with the higher capacity stops charging when the lower capacity battery is fully charged .So you cannot fully charge the larger battery.
    Does anybody know how to overcome this ?

    Barry Wilkins
    Tags: None
    • PCBONEZ
      Grumpy Old Fart
      • Aug 2005
      • 10661
      • USA
      #2
      Re: Charging Lead Acid Batteries

      If they are in parallel the charger will see the average voltage and since the charger charges to some set voltage I don't see how your assumption is even possible.
      .
      Mann-Made Global Warming.
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      Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
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        Comment

        • mysterfxit
          Member
          • Apr 2011
          • 31
          #3
          Re: Charging Lead Acid Batteries

          Just googling I found the problem explained as the battery with the least impedance discharges (and I assume charges) at a faster rate than the other one. So over time one battery gets cycled repeatedly while the other is hardly used.

          That means you would get double the capacity, but you won't get double the life of using a single battery.

          http://www.rcgroups.com/forums/showp...18&postcount=3

            Comment

            • PCBONEZ
              Grumpy Old Fart
              • Aug 2005
              • 10661
              • USA
              #4
              Re: Charging Lead Acid Batteries

              "Level of charge" is called voltage and if they are in parallel they are at the same voltage.
              If one drops by 1 volt then so does the other.
              .
              Mann-Made Global Warming.
              - We should be more concerned about the Intellectual Climate.
              -
              Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
              - Dr Seuss
              -
              You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
              -

                Comment

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