Discharging a Super capacitor

Discussion in 'The Projects Forum' started by Macky Buenaflor, Feb 25, 2016.

  1. Macky Buenaflor

    Thread Starter New Member

    Feb 25, 2016
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    How do you discharge a super capacitor without the use of any discharging circuit? What load can I use for it to be discharged to near single digit volts in minutes? Can I use an LED light here and if so, how long would it take to discharge it if I'm using a 3-5W LED light bulb? Thank you! :)
     
  2. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    What voltage is the cap charged to?
    What is the capacitance?
    What is the rated Vf of the LED?
     
  3. HitEmTrue

    Member

    Jan 25, 2016
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    Under what circumstances to do you want it to discharge? If it lights the LED, there will be a circuit. :)
     
  4. tcmtech

    Well-Known Member

    Nov 4, 2013
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    I prefer to use super resistors to discharge my super capacitors. ;)
     
  5. Macky Buenaflor

    Thread Starter New Member

    Feb 25, 2016
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    Sorry i forgot to put in the details
    48V, 165F supercapacitor. :)
    Any other way to discharge it that you would recommend (besides having a discharge circuit)? Thank you! :)
     
  6. wayneh

    Expert

    Sep 9, 2010
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    No circuit, no discharge. Except for a slight leakage.

    How quickly do you want this to happen?
     
  7. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    :confused: Anything conductive connected across the cap would constitute a discharge circuit.
     
  8. tom_s

    Member

    Jun 27, 2014
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    i was going to suggest a decent flat blade screwdriver

    but i won't :)
     
  9. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    A 220V 3kW fire would make a relatively safe load to discharge the cap.
    Here's the discharge curve over a 100 minute period
    DischargingSupercap.PNG
     
  10. kubeek

    AAC Fanatic!

    Sep 20, 2005
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    The capacitor when fully charged stores roughly 190kJ, so if you were to draw 5W from it it would take 38000 seconds to discharge, that is 10.5 hours.
     
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