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# Is it possible to run a 1.5 volt motor off of standard capacitors? Answered

I'm new to electricity and would like to make a small vehicle that uses capacitors to power a small motor (described above.) Would this work at all? are there resistors or anything that I would need? and if this could work, what types of capacitors would I use. the vehicle needs to move about 7.5 meters.

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sure, what you need is known as a "super capacitor."  Basically it's a capacitor that can hold more electricity than a normal capacitor the same size, but in a smaller size.  There's more to it, but I don't want to over complicate it :P

I'm not exactly sure what size of a capacitor you need, because that depends on the fficiency of your motor and how you hook it up to your car and such.

Super capacitors are more formally known as electric double layer capacitor

You want one rated at 2.3 or 2.5 volts or anything higher than 1.5 volts, and a few farads.  You can get one from www.mouser.com
like this one:
http://mouser.com/ProductDetail/Cornell-Dubilier/EDLHW106D2R3R/?qs=sGAEpiMZZMsCu9HefNWqptJLMjYUXkmnMNQzjXAXIKY%3d

to play it safe, get a capacitor with more farads (more farads means it'll power your motor longer, the capacitor in that link should power your motor for a while).

to charge the capacitor, you can just take a normal AA or AAA or C or D battery, attach the - of the battery to the - of the super capacitor and the + of the battery to  the + of the capacitor (for a super capacitor of that size it make take a while, like up to 30 or 60 seconds to fully charge it.  To discharge it in the motor, just connect the 2 motor wires to the 2 wires from the capacitor.

Check out the circuit diagram:
http://www.scribd.com/doc/17684600/SuperCap-Battery

Mind you, this is like a 9v battery.  You will need to modify something, but I'll be damned if I know what it is...

The problem with driving anything with capacitors is the discharge curve.
The power from the motor will drop off verrrry quickly.

What you need is a much higher voltage than the motor needs (energy stored = 1/2 x C x V^2^

Then you need a switched mode regulator to convert your high voltage down to a low one for your motor.

Steve

Yes, but not for long.  A resistor (maybe 100 ohms) will slow down the discharge of the capacitor, but also decrease the power to the motor.