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by Animats 944 days ago
The big advantage of fast charging is that charging stations are smaller. With hours-long charging, everyone needs a parking place with a charger. With 20-30 minute charging, you need a big lot with parking stalls and something for people to do for 20-30 minutes. With 10 minute charging, you're almost at gas station throughput. With 5 minute charging, you're at gas station throughput levels.

As I wrote a few days ago, once charging is below 10 minutes, charging stations work just like gas stations in terms of throughput. We will see gas stations converting directly from gas pumps to chargers. (Unclear if gas pumps can coexist near high-powered chargers; gasoline vapor and high voltage electricity should not be in the same space.)

2 comments

Just off highway 80, the first exit after crossing the Yolo bypass on the way from Davis into Sacramento, there's a 7-eleven store/gas station/ChargePoint.

The chargers are not right in with the pumps, but not all that far either.

Street view link but the imagery is 6 years old so no ChargePoint visible. The chargers are where the unhitched semi cab is parked. You can see better pictures by looking at user submitted photos for the ChargePoint. https://maps.app.goo.gl/EEnpFRwwv49fkUPo7

For gas-station throughput, you need replaceable batteries which you trade at the station, or 3-minute charging. With 10 minutes you still need that parking lot and something better than your typical mini convenience store. But - it does go a long way, for sure: 10 minutes is something you're willing to just accept as a stop along your way, while 30 minutes is something that you would try to plan in advance.
Replaceable battery isn't easy and likely won't happen for cars. Maybe for airplanes when the time comes, but even then I'm a bit skeptical... Maybe for part of it for bigger jets.

3min is better than 10min, but ask anyone if they'd prefer to fuel up 3 times slower and pay half the cost and I bet most everyone would say they would.

For fueling up, you must be there until it's done. For charging you don't. You connect your car and go inside the convenience store. With 10min, that's excellent. Chances are most everyone will either exit their vehicles, plug it in, go back inside their vehicle for 10min, walk around for a bit, or go to the store for a quick errant. In any of those cases the experience will be better than dealing with fuel.

China is already doing it. Replaceable batteries are seen as the way to go over there and multiple companies are already offering it. Drive your car in and a robot will drop the old battery out and lift a new one in. No more hassle than a carwash.
It definitely works well for scooters where you don't need much real estate to put in a swap station.

https://www.gogoro.com/gogoro-network/

From a logistic point of view, replaceable batteries is a nightmare to manage.
It's been tried. See Better Place.[1] Battery swapping was a bet against better batteries. Even in Israel and Hawaii, where you can't drive very far, it was a losing idea.

[1] https://en.wikipedia.org/wiki/Better_Place_%28company%29

Nio, in China, has revisited this, successfully.[1] They have about 2000 battery swap stations and claim to have done 30,000,000 battery swaps so far. They have a few demo stations in Europe.

The idea is to use smaller batteries for cheaper and lighter cars. Range is less but batteries are swappable for long trips.

[1] https://electrek.co/2023/11/21/nio-is-joining-forces-with-a-...

I live in Israel(/Palestine), and I can tell you that Better Place' failure here had very little, if anything, to do with the use battery replacement logistics.

(Of course, electric cars are not a key need in Israel anyways, the country is in dire needs of mass transit system improvement and integration - which would significantly reduce car overuse and congestion problems.)

Can't be much harder than Calor gas cylinders.

The whole battery replacement situation is why EVs depreciate so much.

If swapping batteries in a modular system became a thing, the depreciation problem might shrink...it would also make EVs a lot more appealing to a significant number of people.

I don't see Calor gas cylinder as the same problem as batteries, because you don't drive around with your Calor gas cylinders. You bring it home, and you bring it back.

With battery, the main issue I see is the same as cities encounter with shared-vehicle: sometimes many people go at the same time from place A to place B, which lead to empty stations and overflowed stations. And you end up having to compensate this effect A LOT.

I admit that the problem is not intrinsic to battery-swap, it's more that it's not adapted to the way people move around. And as people don't move around randomly (which might be the best scenario), the solution is not as simple as the Calor Gas cylinder problem.

The swapping station looks fine for a new technology endlessly claimed not to work. (lmao)

https://youtu.be/qd0WPw3p2MQ

Lets not stop there, you also want to be able to dispose of the battery if you can no longer control the heat.

Currently the solution is to submerge the entire car or let it burn out on the spot. Takes about 2 days but it can randomly reignite.

https://youtu.be/lF-ubRP2ihc