Super-Duper-Uber Capacitors On The Way!!

[auplater]

My thoughts as well...

think about the "crowbar on a car battery" scenario..

I can imagine exploding carbon nanotubes scattering debris

"They also dismiss the several thousand amp currents that it would take to charge the thing in the claimed time as "no problem"."

Having dealt with thousands of amps (in chromium and nickel plating, electropolishing, etc.) I can assure you, it's anything but "no problem"... sounds like researchers looking for follow up funding rather than competent enigineers developing practical applications. Think 350 x 10^5 amp-seconds to determine reasonable recharge rates... not to mention the particulars of distributing this charge into the capacitor uniformly and repeatedly... not a trivial pursuit

John L.

[ak_47_boy]

Imagine the almost instantaneous discharge of a car battery into a laser!

[JohnG]

All double-layer caps that I'm aware of achieve higher voltages via series combinations of caps. The voltage limitation on a single cap is there to prevent an electrochemical reaction from starting. They say a higher voltage due to nanotubes, but not how much higher. This probably means they are purely speculating, or it is not substantially higher.

I'm not dissing the technology, which, if it pans out and the cost is reasonable, it likely to be very useful in energy storage applications. I think it's unlikely that it will be much good for audio. Just my own speculation, though.

John

[valveitude]

I think it's unlikely that it will be much good for audio. Just my own speculation, though.

If they have comparable ESL/ESR, and voltage limitations, to the current ultra-caps, I would tend to agree...but...if a cap with a couple dozen Farads at around 12V or so surfaces at a reasonable cost I can see some uses. First thing that comes to mind is a filament/bias supply that charges while the amp is "off", then disconnects from the line while playing. Ditto that for the B+ if the voltage capacity is available (pre-regulator of course).

Of course, as you've said, this is all speculation until we see something tangible. It is exciting to see the new nano technologies starting to take off though.

Casey

[JohnG]

If not ultracaps, a promising battery technology is Li-Fe phosphate, such as that made by A123 . Energy density is probably a lot higher than an ultracap can reach, and they are available today. You can find them in high-end DeWalt cordless tools, and I've seen them for sale by R/C hobby companies.

Not cheap, though.

John

[scott wurcer]

Originally posted by JohnG
All double-layer caps that I'm aware of achieve higher voltages via series combinations of caps. The voltage limitation on a single cap is there to prevent an electrochemical reaction from starting. They say a higher voltage due to nanotubes, but not how much higher. This probably means they are purely speculating, or it is not substantially higher.

I'm not dissing the technology, which, if it pans out and the cost is reasonable, it likely to be very useful in energy storage applications. I think it's unlikely that it will be much good for audio. Just my own speculation, though.

John

I lost track of the patent they were waving around, but these folks were definately fishing for money. Their spin was that electric cars won't catch on until you can "fill 'er up" in about the same time as a tank of gas.

Another non-trivial problem is the swiching regulator you need to deliver constant voltage as you discharge the capacitor.