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Comment by FireBeyond | Hacker News Reader

"Tesla discontinued battery swap because people do prefer to spend 1/2 hour charging, even when traveling with sleeping children."

That was set up to fail.

There was only one battery swap station. It was aimed at people commuting between LA and SF. Except:

- you had to book in advance to use it

- you had to pay a fee to use it

- it was set up across the street from a Tesla Supercharger

- despite ostensibly being for the commute between those cities, it was actually 15 miles away from the freeway, making for a significant detour

If I was Elon Musk and wanted to demonstrate how people would much rather use charging stations than any kind of battery swap program, I think the above is a pretty good example of how I'd set up my battery swap program (for failure).

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Battery swap doesn't really scale. It's hard to imagine battery swap stations being set up wherever you could conceivably need one, with all the associated infrastructure and labor costs, just so you can swap a battery in 10 minutes rather than supercharge in 30.

And remember, chargers of the future will be faster still. CCS has been designed to scale to at least 300kW.

Yeah, it definitely seemed like it was too complicated of a process to be able to be anyone near as simple as recharging or refueling is.

From first principles, a battery swap station seems to add just one relatively isolated component to an existing charge station... they would use the same power infrastructure, the same authorization protocols, the same locations...

The economics completely change with fleet vehicles (aka, self driving taxis). Instead of taking an entire car out of commission for half an hour, you can just replace the battery in 1 minute and keep the car on the road and earning money. Because both the car and battery swap station is owned by the same company, there's no arbitrage between trading an old, worn out battery and a new battery and fleet cars can be designed alongside the swap station to make the entire process entirely automated.

But the big plus is that if you design a fleet system around battery swap, you can get away with puny batteries on the vehicles. A battery sufficient for 1 - 2 hours of city driving is optimal which saves both cost and weight for the vehicles. Instead of relying on expensive, power dense advanced Lithium batteries, you can shove cheap batteries into the thing, scatter the entire city with drive-thru swap stations and drive the cost of transportation way down.

While that's true, I think you can also have taxis stop at charging stations more often when they aren't in use. Particularly if you have self-driving taxis, you're not bothering passengers by doing that. You could even have trucks with large batteries which act as mobile charging stations.

i strongly disagree with your thesis that a 1-2 hour long driving capacity sized-battery is optimal. If you have an electric car, being able to not constantly worry about whether you can drive home is far more important than the cost of recharging. its so cheap it almost doesn't matter, like $10 for an 85kwh tesla. not worrying about running out of power is the big value.

Yes, for individually owned cars, range anxiety is a real thing. I'm talking about electric taxis which shuttle multiple people around on short trips throughout the day.

15 miles from the freeway? Try less than a mile from I-5: https://goo.gl/maps/bDJACbS8XNE2

As a Tesla owner, I didn't think all of the past back-and-forth about the swap station in blogs was that interesting. I eat dinner in Harris Ranch.

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