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How long does it take to charge a 230CCA car battery?

  1. Apr 13, 2010 #1
    I have a 230 CAA car battery, and 2 solar panels in a parallel circuit (one is 15V, 300mA, 4.5W, the other is 15V, 125mA, 1.8W). I know that these are under optimal conditions, so please assume that they are. How long would it take to charge my car battery with these solar panels?
     
  2. jcsd
  3. Apr 13, 2010 #2

    russ_watters

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    Staff: Mentor

    A standard car battery is about 40 amp-hours, so if you get about the right voltage from your panels, that's 40/(.3+.125) = 94 hours at peak power. You'll be lucky to get that 4 hours a day on average unless you aim the cells, so that's about 23 days.
     
  4. Apr 13, 2010 #3
    How can I find out how many amp-hours a car battery has for sure?
     
  5. Apr 13, 2010 #4

    russ_watters

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    Staff: Mentor

    Find the model number and look it up online.
     
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