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  1. Batteries have been the Achilles’ heel of electric vehicles since the 19th century.  Electric motors have always been more powerful, cheaper, smoother and quieter.  The problem was getting sufficient energy to feed them.

    If Dyson and Sastry have built a better mousetrap, the world will beat a path to their door.  Every maker of smartphones and tablets wants more battery energy in a smaller, lighter package.  They’ll pay the premium to develop the technology to the point where it’s cheap enough for EVs.  This happened when NiMH replaced lead-acid, and again when Li-ion replaced NiMH.  When the solid electrolyte is ready for the world, the world will leap to it and never look back.

    That said, what does a 1143 Wh/l battery mean?  It means a 100 kWh Tesla would have a battery pack of roughly 90 liters… a hair less than 24 gallons.  In other words, about the size of a ICEV’s gas tank.  Only you can make it thin and flat and incorporate it into the floor, freeing up the gas-tank space for a rear-drive motor for AWD.  You’ve already freed up most of the space occupied by the engine and devoted it to cargo.  You get a whole lot more “car” in your car.

    This stuff is going to take off like a rocket.  Oh, yeah, electric cars tend to have rocket-like performance too.

    The only remaining issue is, where do you get the juice to charge these things?  We all know the answer to that.

    1. For a long time, I have seen metal-air (zinc-air or aluminum-air) batteries as being the big development for electric cars. Sure, it would not be a “plug in” battery — the “recharge” would require draining “spent” zinc gel with fresh gel, but the energy density is so much better than Li-ion batteries.

  2. Toyota and VW have openly stated they are heavily looking into solid state batteries (see the Audi Aicon concept car), and I believe that BMW and Bosch (one of, if not the, largest automobile suppliers globally) have stated it as well. GM’s early interest in Sakti3 shows their interest as well. Basically, the auto industry seems to have this well covered, but it will be interesting to see who is able to commercialize it (assuming that it can be commercialized) first.

    It will also be interesting to see if Tesla is agile enough to switch over if the solid state batteries are far superior to the traditional Li-ion batteries.

  3. the energy density of Li-ion batteries could be improved by a factor of 2-3

    Is this like the Goodenough “scam” paper on solid state batteries? As far as I can tell, the Goodenough paper discussed improvements in energy per volume, not energy per mass. Reading on, I see units “1143Wh/liter”, which indicates yes.

    Is “energy per volume” ever a limiting factor? Maybe cell phones and other portable hand-held devices? My understanding is that “energy per mass” is the limiting factor for most applications, including electric cars.

    Similarly, “energy per volume” and “energy per mass” are basically irrelevant for grid-scale storage, where the metrics that matter are “energy per unit of rare and expensive materials” and “energy cost of battery vs energy stored in battery over life (often described by ESOI)”.

    Apologies if I’m grossly misinformed.

    1. @JohnSmith

      As is the case in most decisions, there are many different “measures of effectiveness” that are worth evaluating.

      Energy per unit volume is an important measure because space isn’t free. Depending on the application, it might be quite expensive.

      For a handheld vacuum cleaner or hairdryer, for example, compact batteries with high energy storage capacity per unit volume leave more room for all of the other components that make the device useful. There is a finite constraint on the overall size of the device, because customers will not be interested in buying something that is too unwieldy. Companies like Dyson have probably done the market research that helps them understand exactly how sensitive customers are to size and how many more would be interested in purchasing smaller devices or how much potential customers might be willing to pay for a device with more capability in the same size package.

      In a very specific application that I am aware of, the volume of a seismically qualified building for housing storage batteries to provide emergency backup power for safety related systems and components is enormously expensive. There is great value in being able to double or triple the amount of energy that can be stored in a given building for plants that already exist. There is also great value in being able to design and build smaller buildings for new plants while still being able to fit in the amount of energy storage that is required to perform vital functions for a specified amount of time.

      In automotive applications, batteries take up valuable space that might otherwise be available for leg room, additional luggage, or a more compact vehicle that is easier to park.

      There is a whole science of decision theory that teaches how to evaluate various options by assigning measures of effectiveness and finding ways to determine the relative importance of each measure for any given application.

      1. In automotive applications, batteries take up valuable space that might otherwise be available for leg room, additional luggage, or a more compact vehicle that is easier to park.

        What “valuable space” is taken up by the in-floor battery of a Tesla?  It may raise the vehicle profile a few inches, but it lowers the CG significantly and the improved handling has been remarked upon since the first test drive.

        The Tesla Model S has already freed the under-hood space for a “frunk”, with or without a front-drive system.  The hatchback space can be used either for cargo or jump-seats, and what an ICEV would devote to a fuel tank has gone to the main drive motor and differential.  All that valuable space reclaimed from the ICEV drivetrain has been given to the owner.  How much can you improve on that?  In-wheel motors?

    2. Also, energy per mass matters because it usually relates directly back to “energy per unit of rare and expensive materials”. Or even unit of common as dirt material that would be needed in ridiculous quantities for the energy storage actually necessary to make unreliables work on the grid.

      1. Speaking of “common-as-dirt material”, silicon has been suggested as a medium for thermal energy storage due to its high fusion temperature and high energy of fusion.  I think this would make a good choice as a “heat battery” for overnight energy storage for combined-cycle gas turbine plants.  These plants could shut down almost completely, being maintained in a “hot-standby” state by hot air bled off the heat battery.

        The heat batteries could be “charged” by anything.  Greens would want them fed by “renewables” (unreliables), but having massive dump loads for excess electricity plays to the strengths of nuclear energy.  The same heat batteries could feed open-cycle gas turbines with backup burners for when the batteries are exhausted, allowing carbon-free peaking generation at least part of the time.

  4. The obvious supplement to the batteries is NASA’s Pu238 powered Stirling engine. Alas there appear to be two obstacles to the use of this for cars. One is the expense of Pu238, but the far more difficult one is safety regulations. So I won’t be able to buy a new car that’ll need no fuel for rest of my life any time soon.

  5. Chuckling here. Seems that energy storage technology is not the static dead end that so many of you have claimed. And solar continues to evolve, as does wind energy. And all three technological arenas continue to become cheaper and cheaper to develop and implement.Seems you guys have been betting on the wrong horse.

    1. @Jon Hall

      You’ve misread my position. I believe that chemical battery storage technology is more analogous to a living thoroughbred horse that is perhaps the equivalent of a 2-3 year old. It is entirely possible for that horse to continue getting faster and setting new records. It may sire or foal off-spring that beat its old records.

      However, when the sun sets, chemical storage batteries are still horses with a limited carrying capacity, limited rate of discharge, and expensive on-going costs for wasted energy on the round trip. They also live shorter lives than dogs.

  6. Yeah, like usual Rod Adams is wrong. Dyson dropped the car and Musk is at least 5 years ahead of everyone else. Just like he was wrong on shale gas. I would really like to hear his thoughts on more things so I can bet against him.

    1. @Joseph Landau

      The article is about a battery technology. It starts with a mention of a car project that has been shelved, but the battery development is still progressing.

      Yes, Tesla is leading in EVs and grid scale batteries.

      I did not accurately predict the growth of shale gas, but I’m not sure that history will declare that my skepticism about the long term dominance of natural gas was wrong.

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