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Solar Panel Debacle

  1. Apr 14, 2012 #1
    We are creating a solar device that locates the optimal position to gather sunlight, and then stores the light in an AGM battery that we have. We have a 6v battery and we ordered 4 6v solar cells. Unfortunately the 6v solar cells did not come in. There are 4v solar cells in one of the labs at school (2 cells 4.2V .18mA No load).

    Assuming we wired them in parallel:
    Could these be used to power the 6v battery up to 4v?

    What would happen after the battery hit 4v?
  2. jcsd
  3. Apr 15, 2012 #2
    Not much would happen. Your solar cell output is a million times smaller that a typical AGM battery capacity of 200 amp-hours. A quick calculation 200amp-hours/1.8ma = over a million hours of charge time with the cells in series. The battery has more internal leakage than that.
  4. Apr 19, 2012 #3


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    Staff: Mentor

    Hi robotics1234! http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif [Broken]
    How many amperes would you say the solar cells can deliver?
    Hardly! But why not connect the photovoltaics series, then feed that nominal 8V to the battery. I think it should work. (You could add 2 diodes in series with the lead from the solar cells to drop around 1.5V if you wished, but I doubt that will be necessary.)
    It will still be flat!
    Last edited by a moderator: May 5, 2017
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