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I need help building a battery.

  1. Aug 10, 2006 #1
    I am a car audio installer. So everything I work with runs off of 12VDC. I wanted to make some fun audio related experiments and film them. One experiment I was thinking of doing was making a bunch of lemon batteries and running a car audio CD player off of them. But I recently learned that apparently lemon batteries can not provide much current or voltage. So does anyone have an idea of how I can make some batteries that will be able to provide about 6 amps and 14 volts? I have some battery acid lying around in my house that I can use. I know I can fill up a large cup with the acid and find a big chunk of copper and place it on the acid and get a large chunk of zinc and place it in the acid and I will have a battery. But the question is will it be able to provide enough current and voltage? And if not how many would I have to make?

    Anyone have some ideas on making a battery for my application? Also does anyone know of any other electricity related experiments that I could do? It does not have to involve audio. Just anything that would be interesting to film.
  2. jcsd
  3. Aug 10, 2006 #2


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    Cut the case off the battery, put the bits in 6 different jars.
  4. Aug 11, 2006 #3
    No, I am talking about building my own natural battery from scratch. Not taking the cells out of an automotive battery and placing them in a jar and filling the jar with acid. Doing that is pretty much the same thing as just leaving an automotive battery like it is and using that. I want to so something a bit more creative.
  5. Aug 11, 2006 #4


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    Do you have a multimeter to measure voltage? Maybe you could do the lemon battery thing. Measure the voltage of one lemon cell then series up a bunch to get the right voltage (there's one battery). For more current make severel of these batteries and parallel them up.

    For 6 amps you'll need a lot of lemons.

  6. Aug 11, 2006 #5
    Yes I have like 6 DMM's. I do not think the lemons will work. I got one and I could only get about 3 volts and 100 mA out of it. Any other ideas?
  7. Aug 11, 2006 #6


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    How about building a fuel cell? I don't know much about them, but building one from scratch sounds challenging and fun. You can even make your own electrolysis apparatus to generate the hydrogen and oxygen fuel components.
  8. Aug 11, 2006 #7


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    Build a thermocouple battery. Obviously you need quite a few of them in parallel and series also, but at least it won't rot away when you aren't using it. Use a large torch of some sort to heat it. Horribly inefficient, but fun.
  9. Sep 8, 2006 #8
    request for elaboration

    I am also interested in setting up a method of producing electricity at home. I wam interested in thermocouple batteries. I wonder if supercooling one of the thermocouple junction would increase the rendering. I have been having difficulties finding information on the net. I found this thread during a search and, although this is off-topic, I thought someone here might be able to help with advice, help finding info, etc.


  10. Sep 9, 2006 #9


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    Construction guy, it really depends on how much electricity you want. Thermocouples are fun because they can produce without any moving parts from a candle or something. However, large scale production I would think would be out of the question. There are better alternatives to doing something in a practical manner other than thermocouples for generating electricity at home. For instance the wind-up radios are far more practical than a thermocouple. I suggested it to the OP because it is unconventional and would be taken to the extreme to run a headunit in a car stereo installation.
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