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Tesla CEO: I’d Bet On Capacitors Over Batteries

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Tesla’s (s TSLA) CEO Elon Musk says he bets that it could be capacitors — rather than batteries — that deliver an important breakthrough for electric transportation. “If I were to make a prediction, I’d think there’s a good chance that it is not batteries. But capacitors,” said Musk at the Cleantech Forum in San Francisco on Wednesday.

Capacitors, or ultracapacitors, are energy storage devices that can deliver quick bursts of intense power and can withstand more charge and discharge cycles than batteries. They’re like batteries, and can be used in complement with batteries.

But it’s interesting that the CEO of a company that bases its technology around standardized, small format, lithium-ion batteries would make such a comment. Perhaps Tesla is doing some R&D on capacitor storage deep in its Palo Alto, Calif. labs?

The original reason Musk came out to California years ago was to do research on advanced, high energy density capacitors at Stanford, and to try to leverage what Musk said was tens of billions of dollars of R&D that’s been applied to capacitors for advanced ship making. But then, that whole Internet thing and PayPal (s ebay) happened. And then Tesla (and SolarCity and SpaceX).

Musk says he’s optimistic there will be a solution found by one or another companies in the capacitor space that “will supercede,” batteries. The capacitor companies I’ve written about include Ioxus, which makes ultracapacitors for transportation in complement with batteries; EEstor, which seems like it’s not ever going to deliver anything; Recapping, which is backed by Khosla Ventures and won an ARPA-E grant; and EnerG2, which makes materials for ultracapacitor makers.

Image courtesy of Tesla.

15 Responses to “Tesla CEO: I’d Bet On Capacitors Over Batteries”

  1. Katie,
    You should interview me if you want to learn what is really going on in the ultracapacitor field. The company I founded 1st Lighten The Load Inc. has the leading technology in next generation of ultracapacitors beating out both GE and EESTOR to a practical real-world inexpensive solution. Check out LTL’s website best regards Dave K.

  2. Cordell


    Why did you not include Maxwell Technologies among ultracapacitor vendors? They are among the few companies who are actually selling products. Experience with manufacturing and real-world applications count as much as the latest and greatest technology which can either be licensed or reverse engineered.

    My own bet is on a hybrid diesel/ultracapacitor design running on algae-derived biofuel. The design would combine a 150hp frontwheel-drive VW TDI diesel with a 80hp rearwheel-drive electric to achieve 6-second 0-60mph acceleration times, 45+mpg fuel economy, (in a standard-size sedan), and a 25-year lifespan. Most vehicle fuel mileage is lost to oversized engines simply to deliver a short burst of acceleration. Ultracapacitors would save fuel not only through regenerative braking and idling, but by the displacing gas-guzzling cylinders needed only briefly for quick acceleration. Relieving a diesel engine of the stress caused by acceleration would also reduce pollution and extend engine life; a diesel runs best at a constant speed.

    Sales figures clearly show people are willing to pay an additional $3000 for four-wheel drive and $3000 for the economy and durability provided by a diesel engine. This hybrid diesel/ultracapacitor design therefore would not be a great stretch financially for most middle-class consumers. Indeed, after factoring in the cost of fuel and maintenance over the vehicle’s lifetime, this design, when produced in high-volume, would beat all other competing technologies.

  3. @Katie,

    Thanks for the response but I am a bit confused. You state that you have not interviewed them lately Does that mean you interviewed them years ago or have never interviewed them?

    You also state that you have been “following” them for the past four years. What does that mean? Are you just reading their press releases? Have you interviewed anyone at Zenn, Kleiner Perkins, Lockheed Martin, Polarity, Sachem or any of their suppliers or customers to verify any of EEstor’s claims? If not, it seems that the sum total of your “following” is merely collecting whatever tidbits of information, news, rumor and gossip you gather online and then forming your own conclusion.

    What exactly do you mean by “following” them?

  4. SuchGoodShoes

    Katie, if you had paid attention to the EEStory, you would know that Tesla & Musk were briefed by EEStor.


    You could have asked an interesting question. Also, did you notice that Recapping Inc’s patent application references EEStor as prior art? It’s not unimportant that Penn State’s Clive Randall & Eric Cross are on Khosla’s Recapping team. Look at the number of capacitor companies who fund various research efforts at Penn State’s Center for Dielectric studies:

    Clive Randall poked fun at EEStor in a briefing given to several colleagues….once upon a time. Now his company is referencing their work. Recapping says their capacitor can store more energy than a lithium ion battery. That’s the exact thing that was originally said by all the experts as being impossible when EEStor said it first.

    But now if Penn State & Recapping say it….oh, not so impossible. So which is it?

    It’s also ironic that Eric Cross was recently honored with a lifetime achievement award….an award named after Arthur Von Hippel, the MIT professor who hired EEStor’s Carl Nelson to help research materials needed by the Department of Defense in the 1950s.

    Or, you could dismiss coincidences….like the skeptics posting the EESCAM diatribes because they lost A HEFTY amount of money investing Zenn. Don’t let their poor decisions deny you a good story. Or do.

  5. McMuftee

    @Tom, go spread your BS at
    Dick Weir is ahead of schedule.
    Dick Weir is so close.
    Dick Weir has never been late more than two months.
    It’s easy to make bold claims when you don’t have a prototype.

  6. What research have you done lately regarding EEstor? Have you interviewed anyone there? Have you checked the latest patent filings and approvals?

    Don’t be too sure to write off the good folks from Cedar Park, Texas just yet.

    • Right now the only company in the super-capacitor industry that you can invest in with a high return is Eestor through the Zenn motor ZNNMF:US OR ZNN:TSXV canada. But for the past year they haven’t done any update… They never get US govnmt credit so I wonder how much money they have left. The most important thing in business is time to market… and right now EEstor is waisting time.

  7. ramon leigh

    It certainly is true that any capacitor that works and has capacity will make batteries obsolete, since we’re dealing with electrical rather than chemical processes. If the device described by EEStor actually worked, it would do a couple of things : 1) make an awful lot of batteries obsolete, 2) make ga spowered vehicles immediately obsoelete. Capacitors will be much cheaper to build, last practically forever, and charge and discharge far faster than batteries. Also they will be a lot lighter and have hugher energy densities. In other words, superior in every way to batteries.