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Transportation Power

Will Future Tesla Cars Use Metal-Air Batteries? 171

thecarchik writes "Most advocates and industry analysts expect lithium-ion batteries to dominate electric-car energy storage for the rest of this decade. But is Tesla Motors planning to add a new type of battery to increase the range of its electric cars? Tesla has filed for eight separate patents on uses of metal-air battery technology (for example, #20120041625). The metals covered for use in the metal-air battery are aluminum, iron, lithium, magnesium, vanadium, and zinc. Metal-air batteries, which slowly consume their anodes to give off energy, hit the news last month when Israeli startup Phinergy demonstrated its prototype battery and let reporters drive a test vehicle fitted with the energy-storage device. Mounted in a subcompact demonstration car, Phinergy's aluminum-air battery provides 1,000 miles of range, it said, and requires refills of distilled water (which acts as electrolyte in the cells) about every 200 miles."
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Will Future Tesla Cars Use Metal-Air Batteries?

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  • by ShanghaiBill ( 739463 ) * on Tuesday April 23, 2013 @03:34PM (#43528615)

    1,000 miles of range, it said, and requires refills of distilled water about every 200 miles.

    My car has a range of 6000 miles. That is how often I have to stop to change the motor oil. Of course, I also have to stop every 300 miles to get some gas.

    • by jandrese ( 485 )
      I think it is 1000 miles of range until you have to replace the batteries entirely, which really isn't very far. It's not quite enough range to get you from Boston to Atlanta.
      • by Andy Dodd ( 701 )

        Yeah. It looks like these are nonrechargeable cells.

        In short, a car that consumes aluminum instead of gasoline to run.

        There's a brief reference to rechargeable zinc-air cells - but the aluminum-air cells seem to be nonrechargeable.

        • by h4rr4r ( 612664 )

          Aluminum is simple to refine again and can be done without fossil fuels. It uses quite of bit of electricity, but so does recharging a car battery.

        • by mlts ( 1038732 ) * on Tuesday April 23, 2013 @04:23PM (#43529131)

          There is a misnomer: These are not batteries but fuel cells. The way the aluminum is "recharged" is by hauling the alumina (aluminum oxide) back to a smelting place and spending 15,000 watts per kilo of aluminum made in electricity.

          My concern about this type of battery is the fact that it requires so much energy to "recycle". Already, 1/20 of all US electric output goes to smelt aluminum, and going with aluminum/air fuel cells would add to something that is a ferocious energy user. (Not to knock the aluminum business -- it is a very useful and vital metal, but it is highly dependent on electricity.)

          • by h4rr4r ( 612664 )

            Then the only question is what mass of aluminum do they need. Adding more electrical output for aluminum production should not be that bad, since it is a known load and unlikely to vary.

          • (Not to knock the aluminum business -- it is a very useful and vital metal, but it is highly dependent on electricity.)

            That is actually the point. It is sometimes called "solid electricity" - its production cost is almost entirely the electricity that goes into it. This fuel cell pack makes use of that efficiently packaged energy. Since you can use the cheapest source of electricity in the world to make the fuel plates, it is very economical.

            Swapping in a new plate pack every 1000 miles is likely to much less of a hassle than a nightly charging regimen (if the system has a decent design).

          • by lgw ( 121541 )

            The efficiency of the batteries isn't bad though: about 8 out for the 15 in. And "charging" the batteries centrally at a smelter would be far less load on power distribution infrastructure than everyone individually charging form the grid.

            There's nothing wrong with using power - that's where improved standards of living come from - the trick is using it efficiently. Of course, you also have to schlepp the aluminum back and forth to the smelter, and add in the cost of that, but if you don't need to be clo

          • 15,000 watts per kilo of aluminum made in electricity

            For how long are 15,000 watts expended? Power usage isn't meaningful in this context. Need a duration to get energy.

      • by h4rr4r ( 612664 )

        Who the hell drives from Boston to Atlanta?
        Have you ever heard of an airplane?

        If the batteries are no more expensive than 1000 miles worth of gasoline it could still work. I have my doubts about that price though.

        • by tnk1 ( 899206 )

          I don't drive from Boston to Atlanta, but I do drive between DC and Northern New York and that is only 400 miles, but it is another 400 miles back. In the current air travel environment it is not worth it to fly that distance, and train service to my destination is inconvenient to say the least. So, an electric that gave me 1,000 miles range would start making electrics quite viable for me as my primary vehicle.

          Of course, that is assuming that the technology didn't require some ridiculous expense to opera

        • Who the hell drives from Boston to Atlanta?

          Not when there's Amtrak.

      • by Dr Max ( 1696200 )
        it's 1000 miles till the aluminium anode has disolved in the water. That mixutre can then be turned back into anodes with the right equipment, or you can put some new plates of aluminium in. It's better than petrol (higher power density and it's not like you can get petrol back at the end of a trip) and it can concivably be made it renewable.
    • RTFA and I think the editor was confused. It says 1,000 miles uninterrupted range is possible. I believe the 200 mile number was just for the prototype.

      In the test car, the water must be refilled "every few hundred kilometers"--perhaps every 200 miles.

    • It's more like having to change your fuel tank every 1000 miles.
    • That's how long it takes to consume the metal spark plug electrodes.

      Also, I have to stop and put in liquid every 300 miles or so, but that is immaterial to my range calculations.

  • I gather zinc-air cells would be rechargeable if it weren't for the water in the air. I've heard of various companies working on rechargeable zinc-air, lithium-air, and even sodium-air.

    • by GigsVT ( 208848 )

      Why would you think that? Al + O to Aluminum Oxide isn't easily reversible... at least not back into anything that's a useful anode, water or no water.

      • by h4rr4r ( 612664 )

        Tell your local aluminum refiner that.

        The GP never mentioned Al though.

        • Refining aluminum hydroxide back into pure aluminum requires a heavy industrial multistage process that would not be easily scaled down to something that would fit in your car. It's like suggesting that you should have a steel mill in your trunk. Not going to happen.
  • I looked up the recycling efficiency of Aluminum in this case and found it was about 15%. This is worse efficiency than the lowest number you see for an Gas Engine. So using something like this for day to day usage seems out of the question.

    But with the right packaging it might be a decent range extender in addition to a Lithium main battery pack.

    • by miroku000 ( 2791465 ) on Tuesday April 23, 2013 @03:57PM (#43528835)

      I looked up the recycling efficiency of Aluminum in this case and found it was about 15%. This is worse efficiency than the lowest number you see for an Gas Engine. So using something like this for day to day usage seems out of the question.

      But with the right packaging it might be a decent range extender in addition to a Lithium main battery pack.

      Internal combustion engines are only 13% efficient. "The total fuel efficiency during the cycle process in Al/air electric vehicles (EVs) can be 15% (present stage) or 20% (projected), comparable to that of internal combustion engine vehicles (ICEs) (13%). " See http://en.wikipedia.org/wiki/Aluminium%E2%80%93air_battery [wikipedia.org]

    • I looked up the recycling efficiency of Aluminum in this case and found it was about 15%. This is worse efficiency than the lowest number you see for an Gas Engine. So using something like this for day to day usage seems out of the question.

      But with the right packaging it might be a decent range extender in addition to a Lithium main battery pack.

      This is exactly what they are using it for in the car in the article. They have a main battery which has a range of 100 miles. So, most of the time, you aren't using up the new battery at all. This makes it a lot more viable. I mean, I dive my car like 10 miles per day most of the time. And then once in a while, I will take a road trip and drive it like 500 miles. So, if every Walmart sold replacement batteries, and gas stations sold distilled water, then this could work out ok.

    • by mlts ( 1038732 ) *

      This concerns me as well, but there is one advantage of using aluminum: The fact that aluminum is portable.

      In a place that has ample hydroelectric or solar power that can easily power a smelting plant, aluminum can be refined from aluminum oxide. Then, the metal can be hauled to wherever it is needed. This way, the impact of the high energy usage can be minimized.

    • by h4rr4r ( 612664 )

      I would like to buy these magic Gas Engines you sell, where can I find them?

      Does this number include getting the fuel to the ICE you describe?

  • Short answer, no.

    Long answer, not in the foreseeable future, unless someone strikes their best luck.
    Metal air batteries (lithium in particular) suffer from a bajillion problem that are not even close to solving in the lab, let alone in a device.
    Someone might within 5 years come up with a working lab demonstrator, but something with enough power to move a car (and a "sports" car as a Tesla at that) is way off, considering the current state of research. So considering that the patents will be expired when the

  • by account_deleted ( 4530225 ) on Tuesday April 23, 2013 @04:00PM (#43528855)
    Comment removed based on user account deletion
  • These are probably defensive patents.

  • According to the Phinergy link, they're using the battery as a range extender.

    They propose that an electric car would have Lithium rechargeable batteries, and also a fuel-air battery (55 lbs of extra weight). You would charge your car normally for "drive around town" daily use, but have the extended range when you need it. (Such as, when you suddenly have to drive out to the Everglades to get rid of a body.)

    At 1000 miles per battery and 20 MPG times $4/Gal = $200. If they can make the unit cost less than th

  • Although some folks call this energy source a metal-air "battery", since it has an anode and cathode and an electrolyte, in many situations, more like a metal-air fuel cell than a "battery" as its anode is consumed in a reaction that is not efficiently reversable from an energy point of view (if at all in some varients) and thus not rechargeable in the traditional sense of an automobile battery.

    Of course, this doesn't make it unusable. In fact, quick mechanical replacemement of the fuel that stores the ene

  • So they're patenting the use of a metal-air battery to power a car?

    Exhausted combination patent anyone?

    • So they're patenting the use of a metal-air battery to power a car?

      Exhausted combination patent anyone?

      It can't be that simple.

  • Alcan tried to commercialize the aluminum-air battery 30 years ago, and largely failed. They even spun off a subsidiary called Alupower, here's their patent portfolio: http://www.patentgenius.com/assignee/AlupowerInc.html [patentgenius.com]

    A more knowledgable article here. [aluminum.org]

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