EEStor Issued a Patent For Its Supercapacitor 603
An anonymous reader sends us to GM-volt.com, an electric vehicle enthusiast blog, for the news that last week EEStor was granted a US patent for their electric-energy storage unit, of which no one outside the company (no one who is talking, anyway) has seen so much as a working prototype. We've discussed the company on a number of occasions. The patent (PDF) is a highly information-rich document that offers remarkable insight into the device. EEStor notes "the present invention provides a unique lightweight electric-energy storage unit that has the capability to store ultrahigh amounts of energy." "The core ingredient is an aluminum coated barium titanate powder immersed in a polyethylene terephthalate plastic matrix. The EESU is composed of 31,353 of these components arranged in parallel. It is said to have a total capacitance of 30.693 F and can hold 52.220 kWh of energy. The device is said to have a weight of 281.56 pound including the box and all hardware. Unlike lithium-ion cells, the technology is said not to degrade with cycling and thus has a functionally unlimited lifetime. It is mentioned the device cannot explode when being charge or impacted and is thus safe for vehicles."
Good enough for a couple days at home. (Score:3, Interesting)
Let's see. 50kwh. That would run my computer for...two days no problem with monitor and broadband modem included.
Gimme two of these and some high-efficiency photovoltaics and good-bye power grid. I don't care if my house is ugly, cover the entire thing with HEPV.
52 kilowatt Hours? (Score:5, Interesting)
TFA:
52.220 kWh of energy
A single car battery is about 200 watt hours. The batteries in the Tesla Roadster holds 53 kWÂh according to Wikipedia.
Now thats an interesting coincidence. I wonder if they just worked out how much capacitor would be needed for the power plant of the Tesla.
Much better than a battery for cars. (Score:5, Interesting)
A capacitor has the ability for almost all braking energy to be fed back into it.
In stop-go traffic this could make a massive difference in mileage compared to a conventional battery.
Comment removed (Score:5, Interesting)
Patent doesn't prove anything. (Score:1, Interesting)
"I have been following this blog for time. I, like most have been very hopeful that EESTOR will be successful. I was very encouraged when they were able to show some third party verification last summer. Then something recently happened that corrected my vision. That something was Gary Madoff. The experts have stated Gary Madoff could not do what he claimed for more than a decade. But peopled believed anyway. Some wanted to believe so much they threw away their entire fortunes. There were two clear signs Gary Madoff was conning people. One, secrecy is a must. Cons must always have a secret process because their process cannot stand independent review. "If I tell you how I do it others will steal my work " is the main stay of any con. Two, A goal everybody wants to believe badly. A con cannot succeed unless the people to be conned are desperate to achieve the goal the con man claims to be achieving. Gary Madoff had secrecy. Gary Madoff had returns everyone wanted to believe were possible. Sound familiar?"
Re:Only a couple of days? (Score:3, Interesting)
I hate to tell you but a P4 isn't modern any more. Not even "relatively" modern.
But your point is valid, especially as the P4s were some of the most power-hungry desktop CPUs ever made.
I've measured my pc at 200 W draw under normal use, most of which will be the graphics card. It probably goes up to 300 W when gaming.
That cell would last me about 10 days of continuous use at 200W if I used it as a UPS. That's crazy.
Now for the important bit. For a car:
Wikipedia says cars use between 0.17 to 0.37 kWÂh/mi
Cell is 52.220 kWh
Therefore a car would have a 141 to 307 mile range, depending on the efficiency of the car.
That's pretty impressive, especially if it can be charged rapidly.
Re:Cannot explode but can be used in cars? (Score:5, Interesting)
Modern cars do depend on a much higher octane rating than historical vehicles.
It's actually the opposite - Our cars are normally built to run on pretty low octane ratings today. We have to take a huge swath of the stack for gasoline to satisfy our demand for it, and the result is that our gas, knock wise, is pretty low.
From what I can find, the Model T ran on 93 octane. Not exactly what I'd call a low octane.
Early gas was actually pretty high octane(but tolerances weren't as tight); we didn't actually need all that much of it and it was still competing against Ethanol*, among other fuels. It was only later that gasoline demand started getting high enough that they started running short on the higher octanes, and needed to mix in lesser octane hydrocarbons.
One interesting fact i came across was that the Model T was Ford's original dual fuel vehicle - it featured manual spark advance control and could run on anything from 100% gasoline to 100% ethanol.
*During this time period, everything was competing. There were dozens of electric car companies; steam, ethanol, diesel, gasoline were all competing.
Re:Cannot explode but can be used in Fords? (Score:1, Interesting)
Re:Highly unlilkely (Score:1, Interesting)
Actually, they claim to have a version that uses 5000V for military applications (think direct energy weapons).
that's *nothing* compared to a tank of petrol (Score:3, Interesting)
Now, using 1 Joule == 1 Watt for 1 Second, that comes out to 566kWh, roughly 10 times what this (and other) electrically powered vehicles can manage.
Looks like they have a long way to go before they have enough juice for mainstream use.
Re:Cannot explode but can be used in cars? (Score:5, Interesting)
Now its good that this thing allegedly won't explode while being charged
Welcome to the wonderful world of internal resistance.
Wikipedia files it under output impedance, although no one outside of maybe textbooks refers to it that way.
http://en.wikipedia.org/wiki/Internal_resistance [wikipedia.org]
In summary, no perfect current or voltage sources exist. All power supplies can be modeled as a "perfect" supply with a series resistance.
In practice the difference can be huge. Short out an old fashioned 10 aH zinc copper gravity cell and nothing particularly interesting occurs due to its high internal resistance. Short out a 10 aH nicad, and good luck dodging the shrapnel.
Another amusing comparison, when NiMH batteries were very new, like in the late 80s, RC car racers like myself were impressed that they held around twice the charge of the old NiCd technology. However, the internal resistance was so high, that they didn't go so fast. I guess in the intervening decades NiMH now has a low enough resistance to use in RC cars, but that sure wasn't always the case.
Internal resistance has always been the problem for supercapacitors. I remember being quite disappointed when, as a kid a few decades ago, I bought one of those newfangled carbon based super caps, like 0.1 farad at 5.5 volts, and expected if a couple thousand uF made a shower of sparks when shorted out, 0.1 farad should make like an atomic explosion when shorted, however the internal resistance of the cap was like multiple ohms so it didn't even spark. I vaguely remember that once charged it ran a LED a long time though.
The problems super caps always had (until now?) is you need a ultra high conductivity for the plates to get a low internal resistance and a ultra low conductivity for the dielectric (not dialectic, that's another story) to get low leakage currents, and both have to be compatible with each other (from an electrical standpoint, sodium metal foil and ultra purified water sounds like a good capacitor design, but from a chemical standpoint, maybe not so good. Chlorine is probably an even better insulator than water in this application). Finally it would be nice if it were made without toxic waste like PCBs or beryllium oxide insulators (both of which have been used in electronics applications in the past). And then there's minor little things like mechanical stability, manufacturing problems, and material sources like tantalum. Their claim to have worked around all those problems is what makes this patent very impressive, if true.
Re:Only a couple of days? (Score:5, Interesting)
The range would depend mostly on how fast you're going. The relationship between power use and speed is (generally) cubic, due to the equation for energy loss to drag.
IIRC, when I was running numbers in a previous discussion here about the smart fourtwo car, I came up with something like 37.5HP (~28KW) needed to maintain 80MPH (Highest speed limit in the US, AFAIK). That would give you a bit less than 160 miles on that thing. Slow that down some and the range significantly increases though.
Comment removed (Score:5, Interesting)
Fast recharge of supercaps is not hard (Score:5, Interesting)
The home recharge rate difficulties you outline don't really exist.
If mobile supercaps become affordable, then fixed home supercaps will be even cheaper, probably by a large factor because they can be much larger and heavier and less energy-dense. (You could even use lead acid batteries in the home charging station if that turns out cheaper.)
This means that your home AC supply can charge your home supercap station at whatever rate the mains wiring can stand (in particular, overnight when the electricity rates are cheaper), and then when the car comes home the home station just slams its stored power into the car's supercap at a huge rate and in a short time.
Transferring high power a very short distance is not a problem: just think very fat copper busbars and motorized conical high-area connections.
Re:No, it's killowatt-hours. (Score:5, Interesting)
My average power consumption is about 30 kWh per day. This varies dramatically from summer to winter, with winter loads being much higher due to an electrically heated kitchen floor, a low-efficiency fan motor on the gas furnace, and heavier use of lighting (although this appears to be a minor consideration).
One of these units would fit nicely into my utility room, and give me about 1/2 a day of power in the winter and several days during the summer. Power reliability in Toronto is excellent in any case, but this would eliminate every blackout Toronto has seen, including 2003.
Maury
Re:Cannot explode but can be used in cars? (Score:3, Interesting)
The EEStor device isn't really a supercap, in that it's not like normal supercaps in either construction or operation. It's "merely" a ceramic cap with a very high dielectric constant and very high breakdown voltage. The model they discuss is 30F in 280lb -- hardly competitive with the little tiny 1F supercaps you can buy cheap. Except that it runs at 3.5kV rather then 5.5V.
Also, you can buy more conventional supercaps with very low ESR these days. For example, Cooper Bussman makes a supercap [cooperbussmann.com] that's 100F at 2.5V, with a 20mOhm ESR. Available at Digikey for $26.
Re:I dunno... (Score:4, Interesting)
And if EESTOR is real, or even if the other ultracaps come down in costs, what will happen is that ppl will charge at night, and either us it during the daytime OR sell it back to the power companies during the day. IOW, they will buy the power at say
Finally, you ppl in the east have an issue because your grid is one big one. Enough of the systems go out and it brings down a number of them. Internet tech needs to be applied here.
Re:But How To Charge It? (Score:4, Interesting)
From the Wikipedia's EEStor article, you CAN fast charge at home without a ridiculous electrical system -- IF you have a second EESU that slowcharges overnight:
http://en.wikipedia.org/wiki/EEStor [wikipedia.org]
"Overnight charging at home should still be practical,[6] as is using a second EESU for the home which could be charged overnight using cheap, off-peak electricity to then charge the EEStor unit in the car in 5-10 minutes on demand - and deliver cheap electric power to the house too, making expensive peak power plants obsolete.[7]"
Re:May not explode, but.... (Score:2, Interesting)
Re:Cannot explode but can be used in cars? (Score:3, Interesting)
Wikipedia is correct; DC current cannot pass through a capacitor, so it is indeed impedance rather than resistance.
You, ah, reading the same wikipedia page I am? We agree about impedance and AC current etc, but the wikipedia page is a totally different topic.
Output impedance
From Wikipedia, the free encyclopedia
(Redirected from Internal resistance)
and then a whole bunch of talk about internal resistances of batteries and such.
What I was getting at is that in a sense an output impedance is a complex measurement with a real an imaginary component, and an internal resistance of a battery (or a big super cap in a DC application) is basically an output impedance with a zero "j" or reactive component. But any one in the industry would laugh if you called it an output impedance instead of an internal resistance.
The whole internal resistance thing is relevant to this super duper capacitor in that if it's low enough, a short circuit makes a big bang. If it's too high then it dissipates alot of energy as heat when you try to draw too much power out of it. If the internal resistance is way too high, you don't get to pull energy out of it fast enough to heat up or blow up anything including itself. The original post was just the usual fear of technology, what I don't understand must be evil, etc, and I'm thinking that a super duper capacitor like this would be inherently safe if it's internal resistance is high enough. I saw talk of micron scale conductors, so I don't envision directly driving a photoflash with this thing...
That's an incredibly good dielectric plastic (Score:5, Interesting)
Back to basics. A capacitor is an insulator between two conductors. The key concept here is that their insulator has an insanely high breakdown voltage, which is why they can supposedly make an ultracapacitor that operates around 500V instead of the usual 5V or so.
The patent says "The alumina-coated calcined CMBT powder and the poly(ethylene terephthalate) plastic have exceptional high-voltage breakdown and when used as a composite with the plastic as the matrix the average voltage breakdown was 5.57 * 10^6 V/cm or higher. The voltage breakdown of the poly(ethylene terephthalate) plastic is 580 V/micrometer at 23 degrees C. and the voltage breakdown of the alumina-coated CMBT powders is 610 V/micrometer at 85 degrees C."
Note how many different units they use. Conventionally, dielectric strength is quoted as KV/mm. So we have
First, why did they make a composite that's worse than either of its components? This would be obvious if they used the same units for all their breakdown voltages in the patent.
Second, those are unreasonably good numbers. The usual breakdown voltage for PET [azom.com] as used in Mylar capacitors is only 17 KV/mm. Why is their PET 35 times as good as everybody else's?
(Check this, please. Look at the actual patent image. [pat2pdf.org] The searchable text version at the USPTO doesn't show math symbols very well.)
Re: can hold 52.220 kWh (Score:3, Interesting)
Re:Cannot explode but can be used in cars? (Score:3, Interesting)
The Model T and Model A were dual-fuel vehicles. The distributor, which sent a spark to each cylinder, was "digital": You used the five digits of your left hand to pull the lever on the steering column to advance the spark timing as you drove. When running on alcohol you would advance the spark timing a great deal more than for gasoline, to accommodate alcohol's cooler-burning, high-octane qualities. The dual-fuel vehicles also had a carburetor that could be adjusted from the inside of the automobile by turning a knob (incorrectly termed the choke) on the dashboard.
Remember that when the Model T was built, gas stations were few and far between. Most farmers ran their cars off pure alcohol because that's all they had access to. The Model T will run off pretty much anything that can burn. It was engineered for a time when there was no infrastructure for cars, i.e., no gas stations, no roads, no highways. If anything, it's a better vehicle than most coming off the line today (as long as we're not counting safety features and comfort).
I think the BS is even higher. (Score:5, Interesting)
The EESTOR stuff has been analyzed---yes buy some random guy on a blog, but somebody who really seems to know what he's talking about.
Only in freshman physics can you say that the energy in a capacitor is simply E=1/2 C*V^2---or more correctly---measure the capacitance at V=approx 0 and then extrapolate.
Barium titanate is definitely a known ferroelectric (this is not misspelled) material with a very high dielectric "constant" k.
But it it is not really constant! At sufficiently high voltages (i.e. interesting for power storage) you get dielectric saturation, meaning that k = k(V) in reality and it declines heavily. You just can't make atoms and electrons do what EEstor wants. There isn't enough place to stably put that much energy in electrons unless you change their energy states--which is otherwise known as chemistry---and gasoline.
And if you have 50 kW-hr or so in a little place, and you get a short thanks to a collision which breaks the circuits, there's no way to NOT have a freaking BIG ASS meltdown and explosion. That potential energy IS going to go somewhere and if it was all in E-fields and capacitance, it will discharge really fast if there is a hint of a dielectric breakdown and this will vaporize.
Only if the 50 kW-hr is experimentally measured, not imputed from a low power separate measurement of capacitance or dielectric constant, will I believe it.
I have the feeling that this patent document may really be used for continuing the funding cycle, not actually protecting a (nearly physically unbelievable) technology.
They probably did create a very good ultracapacitor with good materials processing, but I bet the energy storage is still in the ballpark range of known ultracaps.
Having it be otherwise would be like saying you've refined petroleum into a new chemical fuel which has the energy density of fissile uranium, and no radiation!
There isn't any Moore's law in thermodynamics.
Re:52 kilowatt Hours? (Score:3, Interesting)
Maybe, maybe not. It's also the case that a battery (like in the current Tesla) has mostly constant power and voltage output over its whole discharge range, whereas a capacitor outputs power more and more slowly as it runs down. I'm not sure that would be acceptable in a sportscar... or maybe the discharge rate in the capacitor is plenty high to begin with? In either event you have to deal with variable voltage output from the capacitor system, which may make the electronics a lot nastier...
Re:That's an incredibly good dielectric plastic (Score:2, Interesting)
A common rule o' thumb is that to double the voltage breakdown of a given sheet of insulator, one needs to multiply the thickness by a factor of 4. The exact exponent used depends on the material type, quality, etc, but the gist of it is that thinner materials can have much higher breakdown strength than one would expect from testing a thicker material.
Many other factors play an important role, such as field strength enhancement due to small radii, voltage rate of change, material defects, humidity, temperature, and so forth.
Finally, there is evidence to suggest that certain concentrations of nanoparticle fillers may increase dielectric strength.
Disclaimer: IANAMS (I am not a material scientist), but I have done some high-voltage design. Dielectrics are still a black art, if you ask me. If you don't believe me, ask a dielectrics expert a quantitative question sometime, and see how long the answer is.
Re:I think the BS is even higher. (Score:3, Interesting)
They also claim to have it safe. Problem is, where are they testing? I do not see that happening. THAT DOES CONCERN ME. You are correct about the explosive part. The good news is that you would NEVER know and would never suffer unlike a gas tank explosion or fire. I suspect that if and when it is brought to market we will see "issues" (think pinto).
What I find interesting is ppl like you claiming that these guys are frauds and that this is about money. The top ppl have a LONG REPUTATION of above ground when they worked at IBM doing harddrives. As it is Kliener is BEGGING to invest more money in them. In the end, we will see what happens.