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I'd prefer standardized, swappable batteries. Imagine driving up to a gas^Wbattery station, you place your car at a certain spot and your old battery drops out and a new one is inserted and off you go, not even having to leave the car. The old battery is charged slowly, cheaply and safely, while you're on the road again 5 minutes before that one guy still filling diesel.

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Maybe, but that only really works if you have a battery leasing concept - like e.g. Renault Zoe. Otherwise, you're swapping something you "own" with something that may be of inferior quality.

Would you really feel happy having bought a brand new car to find the most expensive component had been replaced with an 8 year old battery just from "filling it up"? What if the previous "owner" had just grounded the car and smashed the battery back into a speed bump or a large stone?

Imagine a damaged battery pack caused a fire and destroyed your car... Who would be liable? You? The garage that you last swapped the battery at (and would you even remember where that was)? The previous renter who may had damaged it? The renter who damaged it 2 weeks ago leading to its failure now? The manufacturer for designing in the risk? Are we going to need to pay to staff 24/7 at every battery swap location to inspect the incoming batteries?

Then there are the safety risks of having a high voltage connector that has to undergo potentially 10,000 cycles during its lifetime. Any slight misalignment will start to cause arcing and contact degradation, increased resistance and higher risk of fires. I realise that this same argument can be made to high speed charging ports as well, but the connector on the car would have to withstand significantly more vibration.

Additionally, the battery is one of the heaviest parts of an EV, so there's a challenge of making something that's easy to remove whilst remaining firmly secure the rest of the time. Such a thing is best supported from underneath, but having top or side loaded batteries would likely cause significant issues with weight distribution. Finally, modern EVs also have contoured batteries to fill the available space in the car, whereas swappable batteries are likely to need to be designed to be interchangeable between models and manufacturers.

To me, I'd see it as having too many downsides. High current charging can be done safely if systems are designed well, as well as still retaining the ability to fall back to slow trickle overnight charging which will probably remain the preferred option for most. We already have a standardised plug that can support this, the increased current can be negotiated over the control lines just as is currently done.

Fill up an electric car with thousands of golf-ball-sized batteries, each holding maybe 10 watts. Small enough they are treated like almost like a fluid. They're dumped and recharged at a station, damaged ones disposed of. Too cheap individually to worry about damage, homogeneous enough that ownership of specific cells is not a concern.

I'll leave the technical details for the engineers. :)

I think Taiwan is like this, but with ev scooters. There are big battery walls, and you take and swap. I think it's fantastic for a town.

Wow, I've just googled it and seen a video about it - pretty amazing !

Gogogo - very popular, and pretty extensive coverage [0]. The only problem is the scooters themselves are so quiet they sneak up behind you on the street.

[0] www.gogoro.com/gogoro-network

Silence (https://www.silenceuk.com/) has scooters and "microcars" with swappable batteries. If I remember correctly, their batteries might have wheels as well so they're easier to move around, since they weight a bit.

There are guys who ride around swapping the batteries in public rental bikes too - they send an alert when the batteries are low and a guy just drives around swapping ones near his current location.

The batteries are small compared to what you'd need for a car - they're maybe slightly larger than a standard lead-acid battery.

In Europe often using diesel powered rental vans ;)

All over mainland china as well, works great for small vehicles like mopeds etc (because the battery is light enough to be swapped by an individual person without tools). Probably helps reduce fire risk as well (because people aren't charging themselves indoors).

Isn't that very common with NIO cars etc? They are also very popular with many other brands, especially for rideshare cars.

https://cnevpost.com/2025/03/04/nio-97800-daily-battery-swap...

This concept makes even more sense for trucks than it does for cars. The batteries are larger, destinations are likely to have appropriate infrastructure, routes are more uniform.

https://www.januselectric.com.au/

Nio does this (only for their cars tho) - apparently takes 3m to do a battery swap. And apparently it's getting to the point where it's close to profitability.

https://www.nio.com/nio-power

https://www.youtube.com/watch?v=hNZy603as5w

They are out there, of course, the standardization part isn't there.

Its already a thing with Nio. Whats more they also allow you to upgrade your battery to higher capacity for long trip ie your normal car battery is 60Kwh but you swap with a 105Kwh for a long trip.

BetterPlace had it. They sold around 700 cars and had some stations in Israel. The idea was a bit too early (2013) and the battery tech was in its infancy, maybe now it can suceeded?

It only works if you lease the battery. And if you lease the battery, you care much less about doing all the things that keep you from trashing it. So either you now have to also lease the car (with plenty of surveillance) or the company has to write off batteries at a high rate.

Isn't the main thing that trashes the battery fast-charging, which is eliminated by this scheme?

> Isn't the main thing that trashes the battery fast-charging

For LFP it’s actually leaving the battery in a high state of charge [1][2], though specifics come down to battery chemistry.

[1] https://iopscience.iop.org/article/10.1149/1945-7111/ad6cbd/...

[2] https://insideevs.com/news/731210/lfp-battery-health-degrade...

After reading the paper the effects of leaving it in a high charge state seems to be smallish. The insideevs.com article never says what the size of the effect is, which is a hint it might be a lot of clicky writing about a nothing burger.

In any case if you are the leasing company, you get to control the BMS. The BMS holds the keys to the kingdom. It can control how the battery can be used: charging rates, max charge, how long max charge will be maintained before it self discharges, min charge, allowed operating temperatures. It seems to me they could mostly eliminate the sort of abuse that seems to concern you.

>The old battery is charged slowly, cheaply and safely..

May be you can be sure of that. But can you be sure of the new battery that you just got, will discharge safely..?

Sure I'd like to swap out a critical part of my car that is also like 60% of it's value to some random part I get in exchange at a highway station!

Google claims "On average, EV batteries weigh around 454 kg" ... pretty heavy stuff to carry around.

If we can do it with scooters today, I bet you we can do it with cars, just need some stronger mechanical arms and whatnot.

With scooters you handle the battery by yourself.

Unless you plan to scale human strength in the next years, it won’t be the same solution.

That's for the whole assembly, obviously. If you were designing for swaps, the BMS and other active components would remain in place and only smaller packs of cells would be swapped. That also addresses the equally specious "don't want to swap out a critical component that's half my car's value" argument.

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