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EEStor: The Story So Far

Energy storage startup EEStor has been very quiet about its technology, so when CEO Richard Weir told us back in January that the company’s high-tech battery could do “a helluva lot,” we considered ourselves lucky to accrue such detailed intel. We got a little more yesterday when EEStor said its equipment, procedures and techniques had been verified by independent third parties — in other words, researchers from outside the company have decided that the special sauce of chemicals in EEStor’s energy storage tech are of a quality and purity that should allow it to achieve EEStor’s bold claims. But while this development is exciting for energy geeks, the super battery tech remains far from operable.

The Cedar Park, Texas-based startup previously had its energy storage unit labeled as a potentially “disruptive technology” by The Economist. Potential markets for disruption include automotive batteries, grid energy storage and even battlefield power supplies.

But the very nature of EEStor’s ambiguously named Electrical Energy Storage Unit (EESU) is very cloudy. The company describes its device as follows: “Using revolutionary ultra capacitor architecture and environmentally friendly materials the EEStor, Inc. EESU will have the capability to compete against all existing battery and capacitor technologies.” The company says its technology can provide 10 times the energy of lead-acid batteries at one tenth the weight and half the price. No wonder people are paying attention.

Founded in 2001 by disk-storage vets Richard D. Weir, Carl Nelson, and Richard S. Weir, EEStor reportedly received $3 million in backing from Kleiner Perkins in 2005, though the startup is not listed in Kleiner’s portfolio.

Electric car maker ZENN Motor Cars invested $2.5 million in EEStor in 2007 for a 3.8 percent stake in the company, putting EEStor’s estimated equity valuation at the time at some $66 million. ZENN has the exclusive rights to use EEStor’s technology in new vehicles weighing up to 1,400 kilos, as well as for retrofits. In the wake of EEStor’s recent technical verification, ZENN has the option to invest an additional $5 million. ZENN says that depending on the investments of EEStor’s other backers, its potential total investment of $7.5 million would give it a stake of between 6.2 percent and 10.5 percent, putting EEStor’s valuation at somewhere between $71.4 million and $121 million.

Early this year EEStor got a huge credibility boost when it signed an exclusive agreement with defense contractor Lockheed Martin, which plans to use EEStor’s EESU for military and homeland security applications. Lockheed hopes EEStor’s units can help lighten the load of today’s high-tech war fighter. While delays have already pushed back estimated production start dates, we hope excited EEStor customers will show off the devices once they are finally delivered.

Previous EEStor and other battery tech coverage:

16 Responses to “EEStor: The Story So Far”

  1. kzulkadoept

    Eestor if legit……where is the DEC. news that proves all research, product blustering is true. DEC/09 was the due date for release on new battery’s storage abilities. Almost the end of DEC/09 and nothing is out confirming your story. Sadly, BS seems to more & more the truth.

  2. William Roberts

    All of this nattering on what it will and won’t do is very entertaining. The only test that counts will be when it hits the market and gets used, modified and beat up in real life. So I’ll wait.

    I look forward to seeing what the hot-rodders will come up with, though.

    To all of you lefties that think that the military will hog the tech and not release it to anyone else, you must have snoozed your history class. Hello… internet, radar, plastic surgery, computers.

    And then there’s the story about a couple of bicycle mechanics from Ohio, back in the day…


  3. @Doug

    But that’s not the way chargers work. You could end up with the same math if you used a capacitor to charge a standard battery — it’s a very inefficient charging method to simply short two devices together if they’re at different potentials. Most chargers (even the little ones for your cellphone) use reactive elements to step up/down the voltage and current-feed the battery. Most often this involves storing the energy in a B-field (inductor) with losses at only a few %. It can also be done with switched-capacitor techniques, although this is only really used in low-power applications due to the size of the cap’s required.

    BTW: I doubt EESTOR will come out with anything revolutionary….

  4. Maxwell

    Has anyone ever looked at who;s on the “Board of Directors” of the world’s leading auto manufactures?
    I believe the oil cartel has long ago bought their way into having a major controlling interest of what the auto manufacturers can make, and they’ve been making very fuel inefficient auto’s for qite a long time. GM is an example and has been a major joke from the get-go. And as an example, look what they did to the EV1, they crushed it out of existence. GM was probably ordered to by the controlling interest.

    The Tesla Motor Company is now offering a challenge to the auto manufacturer’s petrol waste, but the problem is being solved at an outrageous price. Tesla claims it’s because of the high engineering cost along with the very high cost of the lithium batteries. EEStor can now possibly offer an antidote to this very clean, purely electric car being so overpriced. However, weather Tesla Motor Company will ever be allowed to enjoy using the EEStor technology is of great concern. Now that EEStor is sitting pretty with a defense contractor is a warning, that it’s only going to be made available to the highest bidder, the gov and special interest nicely seated government contracting.

    To finally get away from the inside gov cozy dealing like where EEStor is headed, is to look at zero point energy now being offered. As an example, Steven Mark replicated what Nikola Tesla invented ages ago.
    His last known device produced approx 20 amps at 850 volts producing over 16,000 watts, simply by taping in to the earth’s magnetic field and converting it into electricity. This is done with a coil without core, a switching circuit and a couple of magnets. Will this ever be available to the consumer? Not likely!!!!

  5. Doug Danforth

    Capacitor charging efficiency

    Claims have been made that only 5 to 10 minutes will be needed to recharge an EESU. I thought it would be instructive to actually calculate what that would mean for fast charging from a previously charged capacitor and slow charging directly to a cars EESU.

    Fast charging
    The charge, q, on a capacitor, C, is directly proportional to the voltage, v, across the capacitor

    q = Cv

    To do a quick charge from a “station” capacitor with total charge Q, capacitance C, and voltage V to a car’s capacitor with charge q, capacitance C, and voltage v at equilibrium between the station and the car we have:

    Q = q + q   (charge conservation)


    CV = Cv + Cv    (equal equilibrium voltages)


    V = 2v

    So if we want the car’s voltage to be v=350 volts then the station must be set at

    V = 700 volts

    Ok, not too bad since this is still well below the breakdown voltage of 1,100 volts mentioned in the certifications. But consider the energy exchange. The energy, e, stored in a capacitor is proportional to the square of the voltage

    e = 1/2 C v^2

    which we will call the unit energy of the car’s capacitor. Then the energy in the station before discharge is

    E' = 1/2 CV^2 = 4 e

    Yes, four times the energy in the car. After discharge and equilibrium between the two capacitors has been reached we have

    E = e + e = 2 e

    So E’ > E . Where did the other 2e of energy go? It went into resistive heating and electromagnetic radiation (if the capacitors are made of super conductors and they are joined by a superconductor switch then at discharge the charge will simply oscillate back and forth between the two capacitors BUT there will be electric and magnetic fields oscillating which is an antenna that will radiate the energy away eventually. If there is resistance in the circuit then this will create heating and more rapid energy loss).

    Conclusion: First charge up of the station takes 4 e units of energy. At first discharge 1 e unit is sent to the car and 2 e units are lost. The second and subsequent charging of the station take 3 e units to recharge (to get back to 4 e) and then again 1 e unit is transferred to the car and 2 e units are lost. Hence

    3 e IN => 1 e OUT

    hence this type of charging is only 33% efficient!

    Slow charging
    What if we do a slow charge directly to the car’s capacitor? Well, how is this accomplished? It is assumed that standard house hold alternating current is rectified and passed through a step up voltage transformer. How efficient is this process? I have no idea but let the efficiency be called f. That is, e’ units of energy from the grid are transformed into e=fe’ units of energy in the capacitor. If it is assumed that this was the process by which the station was charged then we see that

    e = fe'    (energy to directly charge car's capacitor)
    3e = f"(3e') (energy needed to charge station's capacitor above voltage v)

    where now f” is the efficiency of transforming to twice the voltage, which I assume has f” < f.

    So we see that direct slow charging is at least 3 times more efficient than indirect fast charging. The absolute energy efficiency will depend on the values of f and f”.

    Doug Danforth

  6. jerry bolduc

    Hey kerry bradshaw…you seem to think that frankf38 is one dumb hombre.

    “Does frankf38 know anything at all about cars or energy? What does he think it means when the emissions tests show that there is virtually no unburned gasoline coming out of the tailpipe. Tell us, frankf38, where did all that “unused” gasoline go to?”

    I’ll tell you where that unburned gasoline and diesel goes…before catalytic converters came along, it went into SMOG! Ever hear of SMOG? That’s why the “emissions tests show that there is virtually no unburned gasoline coming out of the tailpipe”. It’s darn sure not because the automobile engine is efficient. Let me ask you something kerry bradshaw…do YOU know anything about cars or energy???

  7. “Signed an exclusive agreement with defense contractor Lockheed Martin.”, which means it is tied up off the market. It will not be used for the common man.

  8. Malcolm

    To address kerry bradshaw:
    Modern gasoline engines are in fact reaching their maximum theoretical efficiency, but that efficiency is only around 30%. Most of the energy of the gasoline in your engine goes into heating up the engine block and surrounding components. Modern copper core electric motors on the other hand have around a 90% efficiency at converting input electrical energy into mechanical energy. Batteries also have a low loss of energy these days, but the limitation has been size, weight, cost and charge time. The eestor concept is to create a high voltage ultra-capacitor which could be charged in seconds and have the same energy density as lithium ion batteries using cheap materials. Capacitor energy storage is dependent on capacitance and voltage, but all modern ultra-capacitors as of yet don’t have a dielectric constant large enough to maintain the high voltage necessary to store a usable amount of energy.
    The third party verified a purity (of barium titanate) necessary to achieve the required dielectric constant (according to eestore’s claims).

  9. Finnsense

    Kerry Bradshaw is half right. What Weir said in interview was that a) they had made a working prototype and that b) they had got the ingredients in place to make an EESU at the automated level. He stressed that his job is to make a production line and the difficulty here is getting pure enough ingredients. Putting them together isn’t difficult as the prototype showed.

    We haven’t seen the prototype though so we don’t know if he’s telling the truth.

  10. kerry bradshaw

    I think frankf38 is in cahoots with the electric companies. Why else would he claim that automakers
    are withholding cars that would be big sellers with $4 gasoline? Why does he imagine that automakers
    want to sell gas hungry cars that don’t sell? Why would all 24 automakers want to satisfy the oil companies? GM recently claimed that the future of autos is electric and is putting all of its development money into those electrics and the Beat and 40 MPG Cobalt. Why does this frankf38 think that automakers can make more fuel efficient cars? Doesn’t he realize that modern gasoline engines can extract virtually all of the energy out of gasoline?
    Does frankf38 know anything at all about cars or energy? What does he think it means when the emissions tests show that there is virtually no unburned gasoline coming out of the tailpipe. Tell us, frankf38, where did all that “unused” gasoline go to?
    Shangri-la? frankf38 needs to havbe a long talk with a physics teacher and stop demonstrating to the world just how ignorant he is.

  11. kerry bradshaw

    You are VERY confused. The third party verification determined that EESTor’s manufacturing processes can achieve the purity specs, etc. that EEStor says are required. In no fashion did those third parties ever claim that meeting these specs means that a device described by EEStor can be made. They would have no idea of whether that were true or not – the third parties are a chemical analysis company and an instrumentation company. They don’t know squat about batteries or capacitors and aren’t supposed to. They have simply confirmed that EEEStor is capable of producing what EEStor claims say they need to produce in order to build their solid state electrical storage units.
    Got that?