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Battery swapping is one of those ideas that sounds good but has enough disadvantages that it's rarely worth it. - Your vehicle design will be less efficient an

by chroma 3y ago

Battery swapping is one of those ideas that sounds good but has enough disadvantages that it's rarely worth it. - Your vehicle design will be less efficient and more expensive than one without the constraint of an easily-removable battery. - Just like with phones, removable batteries mean that you have more ingresses for water and dirt, hurting reliability. - 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. - 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. - 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. All of these issues mean that battery swapping drastically increases cost and complexity for little benefit. A swap will take five minutes, while charging to 80% can take as little as 15 minutes. There's also the issue that batteries are valuable, and the owner of the vehicle probably wants their original battery back (or at least one without more wear & tear). Then you get into issues of compensating or charging people thousands of dollars depending on their new battery's degradation level. It's much simpler to give up on swapping and focus on improving charging speeds, which is exactly what Tesla did.

gamblor956 3y ago
Yes, these are all issues for personal-use vehicles. It's much less of a concern for trucking companies, many of which already have multiple depos across their routes and thus are already in a position to swap batteries from one truck they own to another truck they own.
- Reason077 3y ago
  Truck batteries are enormous and swapping them would be a huge logistical challenge / pain in the ass. Better to just swap the whole tractor unit out if fast charging is not available for some reason. After all, it’s really just a battery (+motor and cab) on wheels.
  - bryanlarsen 3y ago
    https://www.januselectric.com.au/ https://www.januselectric.com.au/ uses forklifts to change their batteries. That should be straightforward for a trucking company.
clouddrover 3y ago
> Battery swapping is one of those ideas that sounds good but has enough disadvantages that it's rarely worth it Nio is doing it: https://www.youtube.com/watch?v=VmWL1hZQmD0 https://www.youtube.com/watch?v=VmWL1hZQmD0 Gogoro is doing it: https://www.youtube.com/watch?v=i5ddtHj_N2E https://www.youtube.com/watch?v=i5ddtHj_N2E Janus Trucks is doing it: https://www.youtube.com/watch?v=9eYLtPSf7PY https://www.youtube.com/watch?v=9eYLtPSf7PY Paying attention to what's going on in the real world is more useful than internet theorizing.
- Tozen 3y ago
  Good videos and point. The situation involved around battery swapping and how to do it matters, versus wholesale dismissing the idea because of a fondness for ICE or close-mindedness. The answer to the question, is not to be stuck on oil forever or until the climate is destroyed.
wolrah 3y ago
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. ---- 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.
- labcomputer 3y ago
  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.

by chroma 3y ago

gamblor956 3y ago

Yes, these are all issues for personal-use vehicles. It's much less of a concern for trucking companies, many of which already have multiple depos across their routes and thus are already in a position to swap batteries from one truck they own to another truck they own.

Reason077 3y ago
Truck batteries are enormous and swapping them would be a huge logistical challenge / pain in the ass. Better to just swap the whole tractor unit out if fast charging is not available for some reason. After all, it’s really just a battery (+motor and cab) on wheels.
- bryanlarsen 3y ago
  https://www.januselectric.com.au/ https://www.januselectric.com.au/ uses forklifts to change their batteries. That should be straightforward for a trucking company.

clouddrover 3y ago

> Battery swapping is one of those ideas that sounds good but has enough disadvantages that it's rarely worth it Nio is doing it: https://www.youtube.com/watch?v=VmWL1hZQmD0 https://www.youtube.com/watch?v=VmWL1hZQmD0 Gogoro is doing it: https://www.youtube.com/watch?v=i5ddtHj_N2E https://www.youtube.com/watch?v=i5ddtHj_N2E Janus Trucks is doing it: https://www.youtube.com/watch?v=9eYLtPSf7PY https://www.youtube.com/watch?v=9eYLtPSf7PY Paying attention to what's going on in the real world is more useful than internet theorizing.

Tozen 3y ago
Good videos and point. The situation involved around battery swapping and how to do it matters, versus wholesale dismissing the idea because of a fondness for ICE or close-mindedness. The answer to the question, is not to be stuck on oil forever or until the climate is destroyed.

wolrah 3y ago

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. ---- 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.

labcomputer 3y ago
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.