Battery Swapping Is Back On The Agenda At Tesla


Back at the dawn of the electric car era, when cars like the Nissan LEAF, BMW i3, and Tesla Model S were just starting to get noticed, a lot of people thought battery swapping instead of battery charging might be the way to go. The logic was sound. If you could swap out a discharged battery and replace it with a fully charged one in a few minutes, that would be better than hanging out at a service area on the interstate for an hour or so, waiting for fresh electrons to insinuate themselves into your battery pack, wouldn’t it?

Tesla battery swapping system

Tesla explored battery swapping briefly, then decided it did not make economic sense and dropped the whole idea after building one facility in Silicon Valley. Now, the idea is back. A patent application dated September 14 describes a system that would raise a vehicle in the air with one set of hydraulic lifts while another inboard lift would drop the battery pack and replace it with a fully charged unit. Here is what the patent abstract says:

A system for exchanging an electrical energy storage system (EESS) of an electric vehicle includes. An EESS station is configured to position an electric vehicle in x and y directions. A vehicle lift raises the electric vehicle to a predetermined height. An EESS lift supports and lowers the EESS and replaces the EESS with a differing EESS. The vehicle lift may be an inboard lift and the EESS lift may be an outboard lift. The system may also include one or more rollers configured to guide the electric vehicle. The system may include a horizontal door having at least one tube positioned thereon for guiding the electric vehicle and/or at least one vehicle chock for positioning the electric vehicle in at least one of the x and y directions. The vehicle lift may include lifting arms to engage jack pads of the electric vehicle.

Such systems could be installed at service stations or even incorporated into a mobile rig. While the patent speaks about using the battery swapping system for  Model S and Model X vehicles, Elon Musk is on record as saying that if Tesla decided to pursue the idea, it would apply to commercial vehicles as well, according to  TechCrunch.

Gee, Tesla doesn’t make any commercial vehicles does it? Oh wait. It’s going to take the wraps off the Tesla Semi on October 26, isn’t it? Hmmm, could there be a connection?

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I have been a car nut since the days when Rob Walker and Henry N. Manney, III graced the pages of Road & Track. Today, I use my trusty Miata for TSD rallies and occasional track days at Lime Rock and Watkins Glen. If it moves on wheels, I'm interested in it. Please follow me on Google + and Twitter.
  • RobSez

    I can’t believe something so amazingly stupid is STILL being considered. I’m assuming of course the whole process is automated and no humans involved. I can’t imagine the system being at all economically feasible if employees are involved in the battery swap. I’m also assuming such stations would be open 24/7×365 as most charging stations are. Also, looking at the drawing, I see a lot of steel that needs to be well stabilized. Mobile? Not so much.

    First, there is the question of real estate and structure. A charging station uses only one parking spot. Battery swapping, storage & delivery is going to take a lot more space and vehicles. I doubt this rig will work if covered in ice and snow. Probably going to need at least a roof and probably some walls around it too. I’m guessing it would be just as expensive as hydrogen filling stations. I’m not a huge fan of FCVs, but wouldn’t just building fuel cell filling stations make better sense? Second, there is the human factor. There are people outside the car wash and oil change places to guide drivers in for a reason. Expecting someone to find their way onto a lift, alone, in the dead of night is expecting a lot of most drivers. Third, there is equipment reliability. What happens if say it’s 10 pm, and mid-swap there is a glitch. How do you get down and go home? If I’m sitting at a charging station and the power fails, I can unplug and find another one. Not an option with swapping. Finally, there is the question of compatibility. Most everyone (at least in the US) can use a common J1772 Level-2 plug. Most new fast chargers have both CCS and CHAdeMO plugs. What happens if there are Tesla, BMW, Chevy, Nissan, etc. battery swap stations popping up everywhere? An ugly mess at least.

    The battery swapping idea works great with toy cars, but it’s just not scalable.

    • kevin mccune

      I don’t think guiding in would be a problem( the car could do it itself) I rather like like the idea of a trailer ranger extender( that could be configured to actually haul stuff) after awhile with the law of diminishing returns things get rather absurd . These problems can be solved ,we may not like the solutions.

  • Tim Jonson

    I cannot understand why the solution to this problem has to be so complicated. Can’t the batteries be slipped in the front or back of the vehicle with something like a pallet jack?
    Or, alternatively, wouldn’t flow batteries make more sense?