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You are mostly right for passenger vehicles, but in the specific context of commercial trucks most of those disadvantages are substantially reduced or eliminated.

> - Your vehicle design will be less efficient and more expensive than one without the constraint of an easily-removable battery.

Commercial trucks sold as a cab-and-chassis configuration, i.e. all the ones that you see the same basic truck under hundreds of different bodies, are already substantially standardized behind the cabin. They are less efficient and more expensive than integrated designs, but as a tradeoff they get the option to use any of those addon bodies that happens to fit length-wise.

This same compatible frame design benefits swappable batteries in that they can be built to go under a standard frame width.

> - Just like with phones, removable batteries mean that you have more ingresses for water and dirt, hurting reliability.

Reliable self-cleaning connectors are already a thing in industry, it's a factor that needs to be considered but it's not a real roadblock.

> - You have to standardize on battery sizes and interfaces. If some new battery technology comes along, or you want to change the chassis (to improve crash safety, for example) you'll have to create a new standard.

This class of trucks has been heavily standardized for decades, CAN still works great for the data link, there's no reason to believe substantial changes will be needed in ways that would be relevant.

> - In modern EVs, batteries have liquid coolant pumped through them. This lets the vehicle keep the battery at optimal temperatures for charging, discharging, and avoiding degradation in hot climates. Swapping batteries means coming up with another solution for controlling battery temperatures.

No it doesn't, plug-and-play dry break connections are already well known. This is a solved problem.

> - In addition to specially-designed cars and batteries, you also need specially designed swapping stations. Again if you ever change the standards, you'll have to upgrade these stations.

Most heavy truck swappable battery designs I've seen either go under or in the front, either way a forklift can do it.

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Again, for passenger cars I 100% agree, Tesla's one station that changed a dozen batteries was nothing but a mechanism to capture a tax benefit, it was never going to work in the big picture because passenger cars are so different. Commercial trucks are intentionally incredibly similar, so it's a different world.



Sure, there are all sorts of workarounds you can apply, but all those workarounds have costs. At the end of the day, economics rules, and if doing all those workarounds costs more than just putting in a bigger battery, they’ll just put in a bigger battery.

Also, you’re forgetting something important: most countries have laws limiting driver hours / mandating driver rest. As a practical matter, with appropriately spaced charging stations, a tractor like the one Tesla built effectively imposes no cost in terms of charging time. That’s because the mandatory driver rest periods are sufficient to charge the battery using today’s battery & charging technology. And on that topic, if you try swapping a battery with a forklift, you’ve already lost (in terms of time). You need a dedicated battery swap machine for the “time economics” of battery swap to make any sense.

So why bother with all kinds of expensive connectors, and the rest when you don’t need it anyway? That’s what you’re up against.


While I don't have a rosy view of swappable batteries in general, I must pick a nit. Drivers are mandated rests, but the trucks are not. A delivery company could operate swappable EVs at near 100% uptime.


Fair point, and you could have multiple drivers too. But the most common objection to BEV trucks is with regard to long haul semis.




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