Ultracapacitors!

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I've been checking up on this story periodically ever since the initial flap over it, and it's finally here. Well, some months ago, but whatever.

http://techcrunch.com/2011/04/14/ioxus- ... gystorage/

Now it's just a matter of whether they can start producing these things on the cheap. Yay for nanotech! Yippee!

Ultracapacitors are cool. We have some in our computer gear to guard against brief power losses. But I doubt they can be used to power electric cars. The physics just doesn't add up.

A modest 135 HP internal combustion engine is an equivalent 100,000 W electric motor.

OK? A 100 vacuum cleaners running at once! Or a 1000 100W light bulbs.

To run an electric car for an adequate period of time you need an extrodinary amount of stored energy. Presently we use large heavy banks of best bateries we have. They store massive amounts of power and naturally require a long time to charge.

Best capacitor we could ever fit in a car would not even turn the engine over.

Finally, to debunk the marketing claims of charging electric cars in mere minutes. I have heard other startups make the same extrodinarily impossible claims.

To run an electric car for just one hour at half its maximum power you'd need 50KW/h of power. To push that much power back into recharging the battery in "mere minutes" you'd need to plug the car into a local substation that powers your entire neigborhood. The cable would need to be inches thick, and to keep the current anywhere near reasonable levels the voltage would need to be dangerously high. It would not be a consumer friendly product.

One zap and the capacitor is discharged. No got for a steady slow flow of electric current.

ruveyn

And what makes you think internal combustion engines are so efficient? That 135HP is only about 20% of the energy released.

Electric cars really aren't as inefficient as you would believe. Personally, I would love to own a Tesla Roadster. They have over 200HP, can go from 0 to 60 in just a few seconds, and they can go at least 200 miles without needing to recharge. Recharging takes about 3 hours at 240 volts.

http://www.teslamotors.com/roadster/specs

No one said anything about efficiency or inefficiency. And I'd love to own a pure electric car.

If you have something to say on the subject just find a way to bring it up without pretending to be correcting someone else.

i think the numbers you are getting are for the raw power the engine releases, you would only need to use about 20% of that for an electric engine, maybe in the range of 30%

@ruveyn
circuitry


other than that, i cant wait to get my hands on one, i read somehwre about someone turning chicken feathers into carbon nanotubes, combine this with these batteries and a new industry is born.

Tesla Roadster has a 185,000 W motor. Almost twice as powerful as what I suggested for a modest family car. That's because the Roadster is supposed to be a sports car.

Please give me some credit. I'm not making this stuff up.

sorry, you are right, i jumped the gun, i went ahead and checked and it matches up pretty good.


that being said the only thing really keeping us away from electric cars is the inability to refuel, automatic battery changers could work, it would take about the same time as refueling a gas car.

Actually, I have been anxiously waiting for any news about the Carbon Nanotube Capacitor Development Project. For one thing, I am impressed with the guy who is heading the project. What I'm more interested in is the fact that the project has managed to funnel a lot of funding into nanotech research in general.

http://techon.nikkeibp.co.jp/english/NE ... lish_PRINT

And there's an example. But the thing is, developing an ultracapacitor that could be marketed for use in electric automobiles would serve as a very good money-maker for these kinds of projects. As nice as it would be to focus purely on sharpening our ability to manipulate matter to a fine edge, no funding, no research. The people holding the purse strings need the promise of something coming of the science within a decade or less, not at least a half-century.

Well, the idea of the ultracapacitor as a carrier of energy suitable for powering motor vehicles would be a very good means of spurring growth in this area. Current ultracapacitors might not pack enough punch to power a motor vehicle for the long-term. However, the important thing is that people are starting to LOOK at the technology again.

http://www.ioxus.com/ultracapacitorFAQs.html

"Can I replace battery XYZ with ultracapacitors?

Usually no, but there are certain low-energy applications such as short-term ride through for generator starting, engine starting, and motor starting that can be powered by ultracapacitors without a battery. The use of high-efficiency DC-DC converters can greatly extend the working voltage range for increased energy extraction from cells while providing a regulated output."

For example, the ultracapacitor being produced by Ioxus isn't really intended to replace batteries for all-electric vehicles. I think their main objective is to try to make it feasible for use in hybrid gas/electric vehicles. However, I think it could serve as a camel's nose under the tent for moving along the development of more sophisticated technology.

But anyway, I am also a little out-of-my depth here, so thank you Dilbert for introducing me to some more concrete information about these ultracapacitors. I'm getting a much better concept of their strengths and limitations.

Lithium battery's would make China the new Saudis.

It's not completely infeasible, there have been ultra-capacitors that can store significantly more energy than lithium ion batteries and could in theory power electric cars. The whole EEstor saga is a good example of that, they manufactured ultra capacitors using a silk screening process to lay down repeating layers of dielectric material and metal down to only a micron thick.

Based on the materials testing on their insulator, it could withstand over 3500V at 10 microns thick. They created a number of sample capacitors large enough to power a car, yet they always had issues keeping the material pure enough to withstand the voltage. Worse still, the material had a ceramic base prone to cracking when exposed to heavy vibration, common for automotive.

When they did develop cracks or impurities, they would discharge internally and run enough current to vaporize the electrodes then explode fairly spectacularly.

Link to original patent

The main use of ultracaps in the hybrid market has always been load levelling. Smoothing out the power demand from acceleration so that you can use the high energy, low power battery technologies. Although because of various safety issues, and the expensive electronics required to manage the capacitors, I don't think any car with that technology has ever got past the concept\prototype stage.

Batteries can be refurbished whereas fossil fuels become air pollution when used. Most of our lithium comes from South America not China.