New Patent Reveals Details of EEStor’s Ultracapacitor Technology
A newly-granted US patent (PDF) for the upcoming ultracapacitor technology from secretive Texas-based EEStor contains a ton of detailed information about their near-mythical Electrical Energy Storage Unit (EESU), which has the potential to revolutionize transportation and our energy infrastructure.
Apparently one EESU weighs 281 pounds, has a volume of 2.63 cubic feet, can be fully charged in 3-6 minutes, is completely unaffected by temperature, will not explode or catch fire in an accident, and provides 52 kWh of electricity (nearly the same amount of energy the Tesla Roadster battery can hold, which reportedly takes the Roadster about 240 miles).
- » See also: Factory Five Electric ‘33 Ford Roadster Debuts at SEMA
- » Get Gas 2.0 by RSS or sign up by email.
The speed at which an EESU can be charged is fully dependent on the type of power source used to charge it. Ultracapacitors, in general, can accept a near-instantaneous charge, so, if you want to take advantage of the super fast recharge time, you’ll need to get a heavy-duty circuit installed. For instance, if you are trying to charge it from a regular US 110V/15A outlet, it could take you up to 30 hours to get a full charge.
Continuing on with the Tesla Roadster comparison (why the hell not?), we find that one Tesla lithium-ion battery pack (PDF), containing 6800 small batteries, weighs almost 1000 pounds and takes up about 4-5 cubic feet of space. The Tesla Battery can be charged in about 3.5 hours, again given a high enough voltage and amperage. Given this comparison, you can clearly see how the EESU, if it ever comes to market, would truly be a game-changer.
I spent a couple hours last night combing through the detailed EEStor patent (PDF) looking for other clues and made some minor discoveries of my own. The EESU consists of thousands of tiny “components,” each consisting of 10 “elements.” In turn, each element has 100 alternating screen-printed dielectric layers of barium-titanate ceramic powder (94%) mixed with PET plastic (4%) and screen-printed layers of an aluminum electrode.
EEstor says the volume of each dielectric layer is 0.0005651 cubic centimeters and the volume of each electrode layer is 0.00005806 cubic centimeters. Given that there are a thousand of each layer in each component (10 elements X 100 layers), the total volume of each component would be: 0.5651 cubic centimeters + 0.05806 cubic centimeters = 0.62316 cubic centimeters.
To get to a capacity of 52 kWh of electricity, EEStor calculates that each EESU would need about 31,351 of these components. Therefore, the total volume of an EESU’s charge holding parts with a capacity of 52 kWh, according to my calculations, would be: 31,351 X 0.62316 cubic centimeters = 19,537 cubic centimeters, or roughly 0.7 cubic feet.
What’s odd about this is that, according to the patent, the volume of a 52 kWh EESU plus its “box, connectors and associated hardware” is 2.63 cubic feet. So, almost 2 cubic feet of the EESU is devoted to the “box, connectors and associated hardware”? I find this hard to believe. Maybe somebody else should check my calculations (look at column 5, Table 1, and columns 9 and 10 of the patent for the details).
If you were to combine two of these EESUs in one vehicle, it would still weigh roughly half as much as a Tesla battery pack, but take the car twice as far (almost 500 miles). Additionally, because of the nature of ultracapacitors, it would still only take 3-6 minutes to charge both packs (again, only if you have a powerful enough outlet).
I’ve still got my fingers crossed that EEStor is really making progress on the EESU. The fact that they’re backed by ZENN Motors and Lockheed Martin lends some credence to their claims, but I’ll believe it when I see it.
Source: GM-Volt
Image Credit: EEStor Patent
As far as home charging goes…… a second cap-pack could be used to store energy from the long charge at night at low peak demands at lower costs and then dumped quickly into the Cap-pack in the car at any time.
The home cap-pack could also be used to balance peak-demands by selling power back to the utilities.
There are soooooooooooo many uses for such a storage device.
Time will reveal how practical this invention will be for all the possible applications. Thank God someone is working on something like this…. Think about how many more ideas and dreams could be developed if engineers and backyard scientists were supported financially and people gave the boot to oil. A few billion dollars would go along way toward stablizing out power needs.
@ nick chambers I have to answer your question!
You’d need a 2nd or 2 additional identical capacitor on a full day trickle charge! Think about it! You have one capacitor thats, as you say, on perhaps a 220/20 outlet (now remember thats AC, cant charge a cap on AC so you need a rectifier and I’d say your looking at 80% efficiency at best, so 20% overhead) charging all day, and when you get your car home, you simply jump one capacitor to the other and charge your cars capacitor at 3500V or whatevers best! now arguably at that voltage you would need some significant safety equipment, but it could be done. And as I understand it (1st year electrical engineering student) the return would only be 50% if you had two capacitors as you would end up seeing equal voltages across both the di-electrics (but then I’m confused… the circuit i built in my head is too simple…). If you had 2 or 3 capacitors at home on a trickle charge, then you would see 66% or 75% of the charge across the capacitor you want to charge up.
Again though, a 35F capacitor at 5000V (this is according to the patent filed by these guys) is a dangerous amount of electricity. It could easily arc across a good deal of air and zap something that even resembles a ground. Getting this thing consumer friendly isn’t going to be easy. Which ties into the “associated hardware” part of your story. The amount of charge this capacitor is going to hold on a plate is easily enough to arc through air (~2000V/cm), so the thing has to be insulated, a very powerful potentiometer must keep the RC time constant (how long it takes for the cap to discharge) very high so that when plugged into more normal circuits its not going to send 100A down a channel designed for 10mA.
The reason these caps are so important is the huge breakdown voltage. Traditional caps break down at say 30 or 40V, but these ones break down at 5000V! The energy stored by a cap is = (Charge * Voltage^2)/2, where charge is in coulombs (btw 1 coulomb = 6.2e18 electrons).
These new barium-titanium capacitors are going to revolutionize electronics as we know them.
Fusion reactor test projects require banks and banks of millions of dollars worth of capacitors! Using these things you can bring that 7 figure cost value down to a 5 figure one! the US Navy contracted (the name escapes me) to build a railgun for their swath boats (as in “hurl this projectile 20 miles and oh btw we need it to hit this teaspoon” the answer is electrostatics). The term “clean up that signal” is going to take on a whole new meaning in communications. I mean on a standard old telephone way more frequencies are possible because of this things use as a band-pass filter (assuming its not polarized :S… is it polarized?). If we equate a telephone line today to a standard FM radio, with range of 80Mhz to 110MHz, using one of these caps in conjunction with an inductor that could keep up, you could get the radio up to say 200Mhz from 80Mhz. The possibilities are phenomenal.
Good stuff.
I have been following this Eestor development closely and especially this discussion about charge time. There seems to me to be a presumption that each and every charging of this device will be from dead nuts dry.
I suspect that this just won’t be the case as very few of us drive 200+ miles per day.
If we just plug the car in every night or even every day when it is at our homes then it seems to me that there will rarely be an issue of running out of juice.
I have absolutely no electrical background or knowledge but it seems to me that I could simply keep the beast plugged in when I am not driving it and everything would work out fine and maybe even not need a high voltage connection at work. As I understand the hypercapacitor concept, it isn’t like they have a memory like old NiCad rechargeables do they?
Geoff, in your post you mention 200mhz down a telephone line just by adding one of these caps. Would the case then be that you would have double the frequency allowing a wider operational frequency for ADSL?
How would this effect distance and bandwidth?
If these caps do eventually pan out, a huge market would as you point out lie with the telecoms industry which in turn would give us higher bandwidth!
Any other ideas on real world alternative uses for the new ultra caps would be welcomed.
Regards
I read through the EEstor patent and I have several questions:
1) This patent has issued, but the prior patent # (7,033,406) comes up only as an application on Google patents. Since it has a #, I must assume it has issued. If not…the new one is dependent on the claim of the one filed in 2006.
2) The manufacturing process describe using HIP to make a void-free material. Where does all the surface area go needed to store the boat-load of electrons if all particle are sintered to a void-free condition?
3) The variation in permittivity data is remarkably tight even for lab results. At 85C and 5000V the variation is only 47 out of 19,818. This is a variation of only 0.24%…extremely small.
4) When thinking about the manufacturability, I note that however long or short each of the process steps, the longest is the residence time in the HIP machine. These are very large, heavy pieces of equipment. These are large forgings that must tolerate 100 atmospheres of pressure. The larger the diameter of the chamber the thicker the ribbing must be to accommodate the load. I have some experience because we had looked at this equipment when looking at how ceramic ballistic armor is made today. The restricted size (12-18″ diam) and lead times (12 to 18 months) for this equipment leads me to question what the ultimate manufacturing throughput can be for this process. The volume of the chamber will ultimately set the hourly throughput.
Just curious.
Sorry:
5) They talk about 3500V, but the largest IGBTs used to do power switching are about 1500V (up from 800V when I last checked 5 years ago - see Semikron). Are there even power switching transistors that can handle the voltage?
Many long range telecommunication technologies rely on band-pass and band-stop filters. These filters are just a capacitor with an inductor in a specific configuration. When you hit a harmonic AC frequency, where the capacitive reactance (the resistance of the capacitor to an AC signal) matches inductive reactance (resistance of inductor to AC), a whole bunch of wierd things happen. This is the basis for carrying multiple signals in the same space. The capacitive reactance is = 1/(2pifC) where C is the capacity of the capacitor. These Ultra Capacitors have insane ratings of up to 35 or even 40 Farads. Now I havnt seen one, but assuming the technology scales and you can get a 5 or 10 Farad capacitor, and assuming we can make it safe, You could, to my knowledge, extend the frequency range (and thus the bandwidth) of current AC signal based technologies significantly.
[...] the stated delivery date on this one, but if they do… world watch out! The cityZENN with an EEStor energy storage device on board may not be the prettiest kid on the block… but does a 5 minute [...]
Well it does sound so good I pray it is real and soon. The cost of them is a big item for having one or two as a quick charging unit.
As George Countryman said above, none will discharged that much if plugged in every night so would not take so long.
Also like EEStor, P2solor is a ray of hope with their 3000 watt solar panel (see patent at http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220070204899%22.PGNR.&OS=DN/20070204899&RS=DN/20070204899 ), one would fit nicely on the roof of an EV/boat/aircraft and will charge while not in use and help reduce drain when in use.
That is a combination that will bring us a true blessing(a 5′ X 5′ double panel would run a smaller home) and with using the EEStor units in the home system for dark times, they could charge each other when you plug in the cars etc, and can be swapped around for long auto trips, high home energy use times (very hot/cold out) etc.
The implications and uses are endless and open a whole world of near “0″ maintenance and operating costs, compared to current technologies now in use (fossil fuels.)
It is presumed that every user of EESU in car will have another EESU at home, charging it at night at low amps and then “only” transfers stored energy to car. At high voltage, it should be possible in couple of minutes.