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Low voltage on Supercaps is a pain. Answered

So, back when All Elecronics had them, I bought 100 of the 1F cooper (relatively high current) supercaps (2.5V), and likewise 100 of the Polyacene "batteries" that Electronics Goldmine is selling (0.6F, 3V, 20ohm.) But I've found the low voltages much more inhibiting than I thought it would be in actually using these. Have people managed to find good uses for these despite the low voltages?

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Padlock (author)2008-11-19

Yah. That would be hard to find a use for. I got it: Super long LED flashligh... No...jk. You could wire them 12volt series then charge them with a computer PSU. I imagine that would give a bigger number of uses for them.

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PirateLabs (author)2008-11-18

Hey, I have found many super caps that are much higher in Farads....(and price)

supercaps

5,000 F

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westfw (author)PirateLabs2008-11-18

Interesting. That vendor seems to have Discontinued their ultra-cap production.
Digikey lists them as non-stocked items; I wonder if they're actually available?

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PirateLabs (author)westfw2008-11-19

350 F caps

westfw:

Sorry, didn't realize that. Above is another link I had saved a while back also. They have many types but this is the page with the 350 F ultracap. I did not see what volts were listed though. I wil dig through some more of my old links when I can.

Bill

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VIRON (author)2007-12-01

TRY putting a few in series and use a higher voltage. 0.2 F at 9 or 12 volts is way more powerful than 1F at 2.5 volts. Probably use diodes to prevent polarity reversals and maybe also zeners to prevent overcharging. They maybe only good for CMOS SRAM power backup. I played with one too and it wasn't much fun. Not even good for solar powered LED nightlights.

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guyfrom7up (author)VIRON2007-12-02

how many farads were yours?

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VIRON (author)guyfrom7up2007-12-02

either 5 or 10 F at 2.5V ... the same ones from All or Mouser. Putting caps in series lowers their capacitance but raises their total voltage. I have a few 1F 5.5V ones that are MUCH more useful, and also one 10V one which probably came out of a weird old 1802-processor-based-computer.

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guyfrom7up (author)VIRON2007-12-02

10 farads at 2.5 volts can be made into 5 volts at 5 farads, but it takes double the space. Having a tiny circuit can change that 2.5 volts into 5 volts, but take double the current. Essentially it'd be the same as 2 10 farad capacitors attached together, but it's cheaper and take up less room.

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gmoon (author)2007-12-02

I'd probably build some sort of solar-recharged-micro-controller-thingie.

Plenty of uCs with low voltage/low current requirements (pico power.) Several AVRs work with 1.8 volt, and I'm certain select PICs are similar.

Of course, what, exactly, to make? hmmm....

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guyfrom7up (author)gmoon2007-12-02

that's the problem with super capacitors, you want to make something cool because it's like a cheap, easy to recharge battery, but you don't know what to make!

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guyfrom7up (author)2007-12-01

I actually was posting an earlier about voltage multipliers and multiplying the voltage specifically so that super capacitors arre more useful (50farads for 6 bucks at mouser!) other things that you could do for higher amps (why with a capacitor) is use a dc to dc converter, like the max1709 chip. thanks for joining my group!

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