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Power Transportation

Can EV Battery Swaps Be as Fast as Filling Up a Gas Tank? (cnet.com) 325

Posted by EditorDavid from the dropping-the-charges dept.
"One of the biggest pain points that comes with driving an electric vehicle is the time it takes to charge the battery," writes CNET. "Startup Ample's new technology can give drivers a full charge in about the same time it takes to fill a gas tank." Ample's model runs on the idea that the fastest charge is the one you never have to do. Its next-generation battery-swapping station can replace the battery on an electric vehicle in about five minutes...

Ample currently operates 12 first-generation swapping stations in the San Francisco Bay Area, mainly serving Uber delivery vehicles. The company expects to launch its next-generation station in the US, as well as Japan and Spain, later this year.
Their drive-through stations work with "just about any" kind of electric vehicle (including larger delivery vehicles), according to CNET's video report. Basically the company uses an "interface tray" that locks under the car (where the battery would go) containing its own charged battery cells. When a car drives in, a robotic system simply removes that tray and replaces it with another with fully-charged battery cells.

The company's co-founder argues this makes charging stations more like gas stations which service every kind of car — and adds that it's incredibly easy to deploy. "There's no construction involved... It comes in pre-built parts. You go through, connect them, test them — and you're up and running."

They've already got a deal with American EV automaker Fisker.
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Can EV Battery Swaps Be as Fast as Filling Up a Gas Tank? More

Can EV Battery Swaps Be as Fast as Filling Up a Gas Tank?

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  • What, this again? (Score:5, Insightful)

    by AlanObject ( 3603453 ) on Sunday June 25, 2023 @04:29PM (#63631628)

    Car buyers that just spent $10,000+ on car battery in their new car, or even a lesser amount on their recently acquired used car, do not want to give that battery up for a copy that is possibly years old and may have problems that their existing battery does not.

    This idea fascinates some people so it never seems to go away. The real problem is that consumers do not want this.

    Tesla tried this for a while. They encountered above, then decided their resources and efforts were better spent on making charging fast enough that this doesn't matter.

    Getting Fisker on board is hardly a ringing endorsement. 0.01% of the market maybe.

    • That’s the thing. Owners of a new EV will want to hang on to their nicely conditioned battery. But when you buy a second hand EV, there’s definitely going to be some anxiety about that €15,000 part that may or may not be a dud. There was an early EV, from Renault I think, where they offered you the option to buy the battery or lease it, and they worked on a battery swap as well. Not a bad idea: no worries about the condition of a very expensive part, instead you pay (by the km driven perhap

      • Re:What, this again? (Score:5, Insightful)

        by shmlco ( 594907 ) on Sunday June 25, 2023 @05:00PM (#63631696) Homepage

        I think the idea is that you buy the car and "lease" a battery on the replacement charging networks that's already one of the swappable ones. So you never had a new battery in the first place, and the price of your initial vehicle is reduced dramatically.

        That said, I think it's a dumb idea for most circumstances. Better to work on recharging technology and improve speeds there instead of building for limited use cases like road trips. We all know the numbers. The vast majority of round-trip commutes are 30 miles/day.

        I could, however, see a use for this sort of thing in long-distance trucking. It's much easier to standardize tractor design than it is to create a system suitable for cars, trucks, vans, and so on.

        • Re: (Score:2)

          by Nutria ( 679911 )

          The vast majority of round-trip commutes are 30 miles/day.

          Which ignores the fact that not every trip is a commute. Not even close to every commute.

          And that doesn't matter to a gasoline-powered vehicle.

        • Re: (Score:3)

          by AmiMoJo ( 196126 )

          That's basically how it works with the Nio battery swaps in Norway. They guarantee a certain state of health for the batteries, and swap them out for repair/reuse when they drop below it.

          If you bought one second hand you wouldn't need to care about the battery, you could just get it swapped out. It's actually very attractive because there is no need to run extensive diagnostics and tests on the battery you are buying, like there is with other EVs to make sure you aren't getting a dud.

        • Is not dumb at all if you live in an apartment building and your car is parked in the street. That's the large majority of car owners I know.

      • How about you buy the car for (say) 20K and then rent or lease or more likely, subscribe to a battery?

        I completely agree that if you just bought a battery, and have taken care of it that you won't want to give it up. You probably wouldn't even want to leave it at a random service stop to pick it up again on the way home. However, if you never owned it in the first place, swapping it out might be just fine.

        I think your points about compromises to the design are far more concerning. Also, the quality control

    • It's just a framing issue.

      Of course you don't want to give up your new $10,000+ battery.

      But what if you don't own the battery in the first place? What if as a condition of owning that class of EV you've got the right to swap in a decent battery any time you go to a fill up station.

      Now, people aren't worried about giving up their good battery because they've always got a good battery.

      Sure you've got some work to do to stop criminal gangs from exploiting the system, but considering there's a lot of tech invol

    • Re: (Score:2)

      by ukoda ( 537183 )
      Actually I think there are niche applications for this technology. The catch is you really need to have committed customer base before making the huge investment needed and that customer base is not going to include normal EV drivers. Every time I point out to ICE owners that charging at home is painless and cheap I get told that there is a large number of cars on the road that are in use 24/7 so they can't even super charge. Most examples they give are bogus but in a few cases, like the police and taxis

    • You know... Like how Tesla's [slate.com] program that never was intended for public use [latimes.com] used to be.

    • Re:What, this again? (Score:5, Insightful)

      by PJ6 ( 1151747 ) on Sunday June 25, 2023 @05:15PM (#63631728)

      Car buyers that just spent $10,000+ on car battery in their new car, or even a lesser amount on their recently acquired used car, do not want to give that battery up for a copy that is possibly years old and may have problems that their existing battery does not.

      This idea fascinates some people so it never seems to go away. The real problem is that consumers do not want this.

      That's not how a system like that would work. Yes you could try to retrofit but generally cars would have to be designed from the start to support it in some sort of practical and standardized fashion.

      When you buy a swapping car, it would be understood you never buy or own a battery (and never charge them yourself), you just pay for the swap at the "gas" station.

      This is clearly better for a lot of use cases, not the least of which being you're NOT sinking a huge amount of money into batteries. The cost and risk is spread out over everyone, and old cells would naturally cycle out after maximum use which is very efficient.

    • Re:What, this again? (Score:5, Interesting)

      by tlhIngan ( 30335 ) <slashdot&worf,net> on Sunday June 25, 2023 @05:28PM (#63631774)

      Exactly. The only people who want this are people who do road trips where their goal is A to B by driving day and night only stopping for gas. I mean, I get the emotions behind it, but these days, those days of peeing in bottles and spending days in a car just aren't appealing anymore.

      I like taking breaks on road trips. Get out in the morning, drive a bit, stop for breakfast, drive some more, stop for lunch, drive a bit more, stop for a break and a walk, drive for dinner and hey, rest for the night. Those breaks are a perfect time to charge my car - I can probably count on a good hour or so, so I don't need superspeed charged in 20 minutes, but hey, if you get me all the way by the time the hour is up, I'd be more than happy. (You don't want it quicker - quicker means you now have to move your vehicle).

      Ditto again at lunch - I'd probably go for an hour to an h our and a half, and I don't need super fast charging - just get it so it's ready when I come back so I don't have to move my car to a parking spot in the meantime.

      Afternoon break? Sure, OK, I might need it going a bit faster as I'll be there for half an hour or so, but maybe not as I'm only going a little over an hour extra driving to dinner and then a hotel.

      Once at the hotel, boom, standard overnight charging works just fine for me. You can do 500+ miles in a day taking it easy, 600+ if you want to "push" this relaxing schedule. If you wanted, you probably could drive 1000 miles in a day even with all these breaks if you decided to drive into late at night.

      I mean, if the goal is to get there as fast as possible, then take a plane. After 500 miles, you'll generally get there quicker by air. If the goal is to enjoy the journey, then perhaps it's time to slow down and not push things on the road. And heck, if you're a small town, encouraging the building of EV charging stations so people can stop by and explore your little town. Even if you're 50 miles away from a big city, encourage the hotel to have chargers so weary travellers might say to stop in your town and rest (and have dinner, etc) rather than push on for another hour and deal with city traffic.

      • Re: (Score:3)

        by dryeo ( 100693 )

        What about apartment dwellers and such who can't easily charge at home? Even basement suite dwellers may not have easy access to a charger.

      • Re: (Score:3, Insightful)

        by Spitemaster ( 1232016 )
        I grew up driving 900km to see my cousins about once a year. We'd drive all through the day - one day there, one day back.

        In an EV, that would never happen. We wouldn't have flown - too expensive. We wouldn't have taken more than one day - that would require a hotel. We wouldn't have made multiple long stops - small children and road trips are already challenging without making it longer.

        You have a somewhat narrow view of why people like to be able to only make short stops.

        • You mean you never stopped with small children for bathroom breaks? With multiple small children a bathroom break would be easily more than 10 minutes, and with supercharging, you just added up to 200 miles in 15 minutes of charging. Thats almost 3 hours of driving added for a 15 minute stop. When I have traveled with small children, stopping every 3 hours is mandatory, if not less! sounds to me you highlighted a perfect use case for long-range EV driving there....

    • Re: (Score:2)

      by redback ( 15527 )

      it only works where you don't own the battery. you buy the car and pay to rent the batteries.

    • Re: (Score:2)

      by xlsior ( 524145 )
      This is the kind of system that would only make sense in limited use cases, e.g. for fleet cars: Like postal service delivery vans where a single company owns dozens or hundreds of like vehicles, where they could own & operate their own swap bays and own all the batteries in use. Delivery vans, taxi companies, shuttle bus services, that sort of thing.

      For personal cars? unless the car in question did NOT charge for the initial battery in the first place, no one is going to want their brand new $10,000

    • It makes sense if you stop thinking about it as buying a battery, and think about as buying the charge. The battery is just the returnable container that the charge comes in. You go to the charge station, they swap the battery and you pay for the amount of charge the new battery has, perhaps with a rebate based on how much remaining charge your old battery has. This accounts for the fact that old batteries can't hold as much of a charge as new batteries.

      I'm definitely making a few assumptions here. The

    • Re: (Score:2)

      by NFN_NLN ( 633283 )

      > do not want to give that battery up for a copy that is possibly years old and may have problems that their existing battery does not

      How do propane BBQ refills work where you live? In my country we swap the empty propane tank for a full one. Almost no one has time to stand around for an attendant to fill up your personal tank.

    • Car buyers that just spent $10,000+ on car battery in their new car,

      The point is that the battery wouldn't be considered "part of the car", any more than a full tank of gas would be considered part of the car and people would not want to replace it with gas that's possibly "years old and may have problems".

      The battery would only be a means of delivering energy, similar to exchanging your propane grill tank instead of jealously holding on to "your" tank, and insisting on only refilling it.

      a copy that is possibly years old and may have problems that their existing battery does not.

      I don't understand this point - surely all you have to do in this case is drive to the

    • I am told that the warranties on jet engines are structured in a way to offer the airlines "power by the hour."

      The contract with the engine maker accounts for the amount of stress put on the engines in terms of number of times the engines are taken to full power, which places the greatest wear on the turbine blades as the tips expand against the housing at high heat loads and such. Don't know if this discourages the crew from selecting max power in an emergency, but a dude from General Electric explaini

    • The other problem is that this means that the batteries cannot be integrated closely with the car - they have to maintain compatibility with the charging chassis.

      There are a number of auto manufacturers who are working on reducing weight by having the case of each cell or module also play a structural role. At the moment, since range is gating factor for cars, the value of weight optimization dramatically outweighs the value of being able to swap out a cell or module. That's of course totally incompatible w

    • The use case is, you buy a nice 150 mile battery city car. This is half as thick as a 300 mile battery. You use it for all the city driving. When you want to go long distance, you tack on another 150 mile battery that you keep swapping every two hours and when the trip is done you drop off the last borrowed extra capacity battery

    • Re: (Score:3)

      by Reziac ( 43301 ) *

      Yeah, that was my first thought. I'm reminded of back when I was using 5 gallon propane tanks... about half those in the swap rack leaked when hooked up (not much, but enough to be annoying when I'd paid for the propane). When I finally got a set that did not leak, after that I was no thanks to the swap, I'll just wait to get mine refilled....

      I'm betting this service will mostly be used by those with aging batteries who are hoping to get a free replacement.

  • Battery Quality/Age? (Score:5, Insightful)

    by Roger W Moore ( 538166 ) on Sunday June 25, 2023 @04:30PM (#63631630) Journal
    The problem with swapping batteries is that all batteries have different ages and qualities. When you drive up to the station for the first time you drive up in your nice new car and they swap its brand new battery for a 4-year-old, cheaper, heavily used one with 66% of the capacity you are not going to be happy.

    Working around that is going to be challenging but not impossible since it will really need the service to own the batteries rather than the vehicle owners. However, it also adds uncertainty to long-distance driving since you have no idea of the quality of the battery you will get installed when stopping somewhere.

    • Re:Battery Quality/Age? (Score:4, Insightful)

      by blugalf ( 7063499 ) on Sunday June 25, 2023 @05:34PM (#63631780)
      Shouldn't be impossible. I mean at a normal petrol station you also trust the people running it to supply fuel that adheres to a certain spec, and not some phony, cheapo shit from a subpar refinery. Word would spread pretty quickly if they did that and they wouldn't last very long.
      • Yes, but a petrol station has control over the quality of the petrol it purchases. A battery swap station will have to recharge whatever batteries are left by people who swap their batteries there. That's why I think it will only work if it is the service provider that owns the batteries and the drivers essentially rent one from them.

      • Re: (Score:2)

        by Shugart ( 598491 )
        There are many companies that own petrol stations. What would it be like if there were only one? Would you be able to trust them i? I would have a concern with battery swapping if there wasn't competition.

    • Re: (Score:2)

      by dgatwood ( 11270 )

      The problem with swapping batteries is that all batteries have different ages and qualities. When you drive up to the station for the first time you drive up in your nice new car and they swap its brand new battery for a 4-year-old, cheaper, heavily used one with 66% of the capacity you are not going to be happy.

      To do this right, a battery swap vendor should track the number of charge cycles on the battery when you bring the car in for the first time and the number of charge cycles added since the last swap. Then, they could choose a replacement battery that is as close as possible to the expected number of remaining charge cycles on the user's original battery had they charged instead of swapping. Even if they temporarily can't provide a close match because of inadequate supply at a particular station, the user

      • True, although how well that will work will depend on battery availability where you swap and you can still end up with your high-quality/new battery getting swapped out for a crappy one plus how fast a battery degrades depends on how much you use it so now you also have to track how someone uses whatever battery they have and degrade the quality appropriately. Even then who is responsible if the battery you have fails while you are using it? I doubt anyone will accept that as just "bad luck" like their wou

    • Surely you pay for how much charge is in the actual battery, and not the same price regardless. So the price for the battery should be charge divided by weight, or something like that. That way you aren't overcharged when using an older battery.

      • Surely you pay for how much charge is in the actual battery, and not the same price regardless.

        Most of the cost of a battery is in the battery itself, not in the electrical energy it stores. That's the problem. A brand-new, high-quality battery is worth a lot more than an older, well-used one so when you swap you could be given a much more expensive or much cheaper battery.

    • Re: (Score:2)

      by Ichijo ( 607641 )

      When you drive up to the station for the first time you drive up in your nice new car and they swap its brand new battery...

      If the dealer sold you a brand new battery then you got ripped off!

    • I can see a solution to this, instead of giving up your own battery pack, just have a rental one installed at a refilling station and never give up your own battery.

    • The problem with swapping batteries is that all batteries have different ages and qualities. When you drive up to the station for the first time you drive up in your nice new car and they swap its brand new battery for a 4-year-old, cheaper, heavily used one with 66% of the capacity you are not going to be happy.

      Yeah, this would only make sense if you never buy a battery in the first place, just buy a battery-less car and a battery subscription service, so you never actually care about the battery state, as long as the battery has enough charge to get you to the next battery swap station. But that assumes you only ever use battery swap stations to get charge. If you'd also like the convenience of doing most of your charging at home and never having to visit a station of any sort -- something most EV owners greatly

    • Re:Battery Quality/Age? (Score:4, Informative)

      by AmiMoJo ( 196126 ) on Monday June 26, 2023 @04:21AM (#63632864) Homepage Journal

      Nio has been operating battery swaps in Norway for a while, and they guarantee a minimum of 90% range when the pack is installed in your vehicle.

      If you were unhappy for some reason you could just swap out for a different pack. Nio monitor every pack and cycle them out for refurbishment or reuse when they degrade.

  • Don't Tesla EV's use the battery pack as a structural member? If I'm right, then swapping their batteries would probably be a bad idea even if it was feasible, which I suspect it isn't.

    • Their newer cars do. Doing so results in a substantial cost and weight savings. Consumers prefer that to the option of giving up their brand-new battery pack for an old one.

      • Don't Tesla EV's use the battery pack as a structural member?

        Yes. Which is also why when a Tesla built like that is involved in a car accident, they are usually not repairable [hotcars.com].

        Consumers prefer that to the option of giving up their brand-new battery pack for an old one.

        Consumers are dumb, and you can't expect them to see what is good for them. Consumers will always prefer immediate pleasure than long-term convenience. Or you can replace "consumers" with "human beings" if you prefer. We are animals, it is extremely hard for (some of) us to think mid/long term.

  • Maybe there would be some acceptance of a rear-facing power socket along with a towing package. That way cars making a long journey could hook up an additional battery or I suppose even a generator.

    battery swap would be quick, the additional battery can be a rental, and the whole thing only used for occasional longer journeys

    for that matter, a portable power bank could be useful for many worksite power requirements aside from travel

    The extra power connector can also be useful for when you park the other way

    • Re: (Score:2)

      by rossdee ( 243626 )

      How about a trailer, with the wheels hooked up to a generator (for regen braking) , extra batteries, and maybe an H2 tank and a fuel cell.

      (Of course if the trailer is small relative to your car maybe you don't need the extra braking ability so much)

  • Strawman. (Score:5, Insightful)

    by whoever57 ( 658626 ) on Sunday June 25, 2023 @04:51PM (#63631674) Journal

    "One of the biggest pain points that comes with driving an electric vehicle is the time it takes to charge the battery,"

    Said almost no EV owners.

    Most EV charging is done while the owner is doing something else: sleeping, working at the office, eating, etc..

  • We would need standard battery packs (Score:3)

    by juancn ( 596002 ) on Sunday June 25, 2023 @04:54PM (#63631686) Homepage
    Long term, the only way this works is if batteries are truly interchangeable.

    Maybe a hybrid mechanism would work best. Essentially the car has two battery packs, a large one, custom, fixed somewhere in the chasis (possibly optional).

    And a removable, but standard pack, that's quickly exchanged for another standard pack. These packs would probably be smaller, and even if they don't provide more than a few miles of autonomy, a quick exchange would make sense.

    Maybe it could also transfer it's charge to the built-in pack (i.e. while you drive, use about 50% of the charge on driving, another 50% on topping the built-in pack, then quickly switch to a fresh one, and keep driving and charging on the go)

  • The batteries in many modern EV's constitute the entire floor of the vehicle, a 'skateboard' architecture. No way to swap that out, and darn hard to even repair them. Upcoming models may have batteries incorporated throughout the structural components.

    Swap-outs can work for short-range "Uber delivery vehicles" that are designed for it, but the "just about any" vehicle claim seems like quite a stretch.

  • Not just an electrical connection needed (Score:3)

    by Nkwe ( 604125 ) on Sunday June 25, 2023 @05:23PM (#63631754)
    Note that many EV batteries are actively thermally managed - they have a coolant loop that is used to warm or cool the battery pack. This thermal management is used for both the charge and discharge cycles. Any sort of battery swap mechanism would need to have plumbing connections in addition to electrical ones. With pluming connection and disconnection cycles, comes the need for air purging and coolant level management.

    • Re:Not just an electrical connection needed (Score:4, Interesting)

      by AmiMoJo ( 196126 ) on Monday June 26, 2023 @04:29AM (#63632878) Homepage Journal

      Nio has sorted that out for their battery swap system that is active in Norway, and China.

      They aren't giving away too many details but it appears that the battery has a sealed cooling loop and its own pump, with a heat exchanger in the car that cools the liquid. It seems to work very well - in Bjorn Nyland's tests the battery temperature was maintained very well over long periods of driving and high power charging.

  • I don't see this working for small, particular cars. People just won't swap their brand new batteries for possibly worn ones. Not to mention in some models battery packs are now structural and cannot be retrofitted for swapping.
    But I think battery swap can have its uses. Bus and truck companies could use battery swap in their fleet with no issues, since themselves will control battery quality.

  • Am I missing something? Who would need this, exactly? Don't people usually charge at home or work or something like that?

  • while you sleep. Problem solved. But! but! but! I can't! I won't! Blah blah blah. Doesn't matter. It isn't about you. If it works for most of the people most of the time, it works.

  • Not the way they build cars now. Cars are Convoluted Overly Complex Puzzle Boxes! With an eye toward ease of assembly, with zero consideration for ease of maintenance.

  • I don't believe it's quite ready for prime time yet, but there is a lot of work going into practical mobile platform flow batteries.

    Rather than a sealed box with all the parts within, the electrical exchange acts more like an engine and you run a couple of special fluids through it from tanks.

    My rough math says you'd need four tanks in your car - one for each fluid charged and one for each fluid discharged - but maybe you could use one tank for each and just speed up the flow to make up for the reduced capa

  • The entire premise behind "battery swapping" basically assumes that all batteries are the same. The problem is, they aren't all the same.

    Even if they are all the same type/model, you are still going to have some batteries that are produced by reputable companies and some that are produced by shoddy companies. Some batteries might be brand new, while others might have severely diminished capacity due to usage & age.

    So do you want to literally roll the dice each time, possibly/probably having your new

  • Any new car battery won't be so new a year later, so I won't care if I get new or old batteries as replacement, since I can swap out whatever I have in 5m.

    I'm not going to want to go sit in a gas station or parking lot of a FoodCo for 30m while I get a Level 3 charge. More like 4 hours for a Level 2. Besides, the manufacturer tells me not to do too much Level 3 charging since it lowers the battery lifetime.

    I just got back from a weekend trip. Had to stop at a suburban shopping mall, wait until a spot opened

  • Even 80 miles of range would be helpful in swappable capacity. That would be ~20kwhrs? Clunky but doable. A swap or two could make a trip doable in one go and help with any “rescues”, like a jerry can for EVs.

  • IMHO, a lot has to happen before we see battery exchange as something that even 10% of EV owners ever do.

    First, most EVs have their packs tightly integrated in to the vehicle, and things like crash testing and other safety engineering are all done based on that. So this hurdle is that the manufacturers have to design for it.

    Next, as others have pointed out, batteries are more than just an assembly of cells in to modular packs. There's also thermal management and control. This also tends to be tightly int

  • LOL...Nio have been doing this for years. The car owner doesn't own the battery, just rents it. Nio takes responsibility for keeping the batteries in optimum condition. It takes a little over 5 minutes to swap a battery.
    The problem is finding a swapping station. I guess they're more expensive to install than a regular charger...though, perhaps not?

  • fat stax (Score:3)

    by bugs2squash ( 1132591 ) on Sunday June 25, 2023 @09:38PM (#63632334)

    if you have a stack of batteries all charged up and laying around waiting for someone to drive up, why not use them to back a super fast charge system. As others have pointed out, that will be limited by the charging rate of the car, so there's that problem to solve, but the grid power should be less of an issue if you have batteries on hand to even out the grid load.

    I think for most people, if they had the option of buying an efficient daily commuter or a battery-swappable long distance tourer they would likely buy the commuter and rent a tourer when/if they needed one

    30-minute charge times are only a problem if you are making long car trips regularly - I imagine that's a small slice of the car using public,

  • not again (Score:3)

    by layabout ( 1576461 ) on Sunday June 25, 2023 @10:49PM (#63632430)
    This lousy idea pops up every couple of years after another sucker VC funds it based on a PowerPoint presentation. Once you live with an ev with at-home charging, the "gas station" model of handling batteries is a non-starter. Instead of building a commercial gatekeeper to fill up your battery, put L2 chargers everywhere. The only people that will lose are VC's and bankers.

    • Re: (Score:3)

      by AmiMoJo ( 196126 )

      If it convinces more people to buy EVs by making them worry less about an additional few minutes on long journeys, it's worth it.

      Bjorn Nyland has some interesting data on covering 1000km in different cars: https://docs.google.com/spread... [google.com]

      You can see that the Nio is only slightly slower than a fossil fuel car with battery swaps, but other high end EVs like the Mercedes EQS with large battery can equal it on charging alone. Where battery swapping does make a difference is in cheaper EVs with smaller batterie

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