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Re:Charging cars at home at night is not the way to go: study by elihu on Friday September 23, 2022 @09:34PM (#32959000)
Battery swap stations are an old idea, but it's really hard to actually pull it off. It requires that all the cars you service have the same battery pack, or that there are at most only a few kinds of battery pack to deal with. The packs have to be stored and charged, so you have the same electrical service requirements plus you need a place to store the batteries, and employees or robots to move them around. You need car owners to accept an ownership model where batteries are leased rather than owned.

Modern EV batteries are almost always liquid cooled, so your removable battery will need some kind of fluid connection that can be disconnected and reconnected without dripping ethylene glycol or whatever on everything, and without getting air bubbles in the line.

Some cars are moving towards structural batteries, which means the car is less sturdy without the battery installed. That might not be a problem if it's just sitting there.

The alternative is to just do DC fast charging, which seems to be good enough for most uses.

Personally I think the long-term solution here is to electrify sections of the major highways at regular intervals, so that cars can charge without stopping. Sweden has some pilot projects involving rails embedded in slots in the road surface. Overhead lines are another option (and they're cheaper), but if they're high enough for trucks to fit, then cars would have to have very tall pantographs to reach.

Re:Charging cars at home at night is not the way to go: study by badrabbit on Friday September 23, 2022 @09:37PM (#32959009)
As a sibling commenter pointed out, NIO is already doing this with millions of swaps already in China.

Instead of electrifying roads for cars, why not electrify them for rail cars and trains?

Re:Charging cars at home at night is not the way to go: study by elihu on Saturday September 24, 2022 @05:07AM (#32960919)
Converting trains over to electric is also well worth doing.
Re:Charging cars at home at night is not the way to go: study by PaulDavisThe1st on Friday September 23, 2022 @10:53PM (#32959353)
> but it's really hard to actually pull it off. It requires that all the cars you service have the same battery pack, or that there are at most only a few kinds of battery pack to deal with.

Precisely the kind of thing government regulation is for. Don't specify what is inside the battery pack, specify the form factor, connection points and attachment mechanisms. Leave the battery companies to figure out the rest.

Re:Charging cars at home at night is not the way to go: study by theluketaylor on Friday September 23, 2022 @10:58PM (#32959373)
Way more complex than that. Different packs have very different voltage and current delivery characteristics. A bunch of motor management depends on the battery pack characteristics, including things like regen braking.

Charge times are already under 20 minutes for the best cars and will likely continue to come down. Swappable batteries would be a massively expensive undertaking that would hugely limit innovation in battery and car packaging for a pretty minimal gain.

I’ve taken my model 3 on plenty of road trips and haven’t once thought it would be better with battery swapping.

Re:Charging cars at home at night is not the way to go: study by ouchjars on Friday September 23, 2022 @11:35PM (#32959535)
To some extent, the forced downtime is a benefit. Instantly refeullable vehicles enable fatigued driving. It's not even healthy to be sitting for that long as a passenger.
Re:Charging cars at home at night is not the way to go: study by theluketaylor on Friday September 23, 2022 @11:49PM (#32959590)
I believe the EU trucking downtime rules actually line up pretty nicely. Building trucks with enough range to maximize the driver time and then charge during the refresh period works out just about right.
Re:Charging cars at home at night is not the way to go: study by vinnymac on Friday September 23, 2022 @11:11PM (#32959428)
I agree. The newer charging stations are so quick at a rest stop, that I don't even notice them anymore. Once it's down to 10 minutes, it won't even be a discussion topic imo.
Re:Charging cars at home at night is not the way to go: study by badrabbit on Saturday September 24, 2022 @10:55AM (#32963181)
I would say 5min. 10min is nothing on a road trip but a lot when you are running late for something. People who make less money tend to care more about this.
Re:Charging cars at home at night is not the way to go: study by theluketaylor on Saturday September 24, 2022 @01:17PM (#32964641)
fast charging isn't need for day-to-day life. The vast majority of cars spend most of their time stationary and slow AC chargers are going to just become more and more common at all parking spots. Never having to stop during normal driving for gas since you start every day with a full 'tank' is a complete game changer.
Re:Charging cars at home at night is not the way to go: study by badrabbit on Saturday September 24, 2022 @01:37PM (#32964852)
It needs to be like 99% of parking lots. It's ok until it isn't. I have had ro refuel my car during a commute many times and barely made it, if electric cars keep contributing to my tardiness I will blame them instead of my lack of adequate planning, even if it worked fine for a whole year before that. It took one experience of being stranded because of bad battery life estimate to get me to dislike them with passion.

What I have learned from thid thread is people who advocate for electric cars are disconnected from the realities of most people. I think it is not possible to change enough people's minds about this, for reducing the impact of climate change, perhaps focusing on cruise ships and electric planes is better while promoting hybrid cars. Full electric cannot happen in the next 20 years at least if I had to guess.

Re:Charging cars at home at night is not the way to go: study by theluketaylor on Saturday September 24, 2022 @01:53PM (#32965024)
Hardly 99%. With a 260 mile-range car I only need to plug in about once a week. People who drive more obviously need to plug in more often, but it's a pretty rare person who would absolutely need to charge every single day. EVs are not for every single use case yet (like long distance towing) and that's okay. They will handle more use cases with each passing year. We certainly don't have nearly enough slow charging points yet, but it doesn't need to be anywhere near 100% coverage before many people who don't have dedicated parking can use an EV with minimal to no disruption.

Battery swapping isn't more efficient or cheaper. You still have to build out massive charging infrastructure all over the place to charge all the swapped batteries, plus you need staff, locations, and equipment to do the swapping, and storage space for the batteries while they wait to be placed back in a car. Plus every manufacturer has to use the exact same battery physical and electrical specs, eliminating all possible innovation in packaging. No one is saying it isn't possible, it just doesn't actually make sense at scale.

I recognize having a private driveway and garage is a luxury, which is why I'm highly supportive of laws requiring multi-unit dwellings to add charging and offering tax breaks for both landlords and tenants to get them installed. Also highly in favour of tax breaks for employers to offer charging in their lots. I also think municipalities should be upgrading the existing streetlight wiring to offer charging alongside street parking.

Re:Charging cars at home at night is not the way to go: study by badrabbit on Sunday September 25, 2022 @12:56AM (#32969050)
To be a bit reductive here, it needs to work for everybody for it to be a viable fossil fuel car alternative. You can't have 1% of people for whom it doesn't work for because for 300M people that is 3M people. Often the people for whom it doesn't work for are the poorest and most vulnerable as well. Imagine taking off the cost of battery ownership and having battery leases subsidized, now you electric cars become even more affordable. Battery swapping from an infrastructure perspective is not mutually exclusive to charging either. You can charge cars with swappable batteries at charging stations. You just need the government to force standardization of both charging and swapping connections. Capitalism will take care of where you have swapping and charging stations. Of course you can force people to buy hybrids as well but they are not well liked due to difficulty of repairing them and that still means fossil fuels.

If fast charging car batteries in less than 5min can be done in 15 years and hybrids are acceptable maybe that is the way to go but even then as a consumer a 20second swap is better than a 5 minute charge. Ignoring what consumers want is always a critical mistake.

I have no doubt fossil fuel cars will go away, the question is do you want them to go away in 10 years, 20 years or 30 years. The sooner they go away the better it is for climate change right? If so, long term "holistic" engineering has no place here. Swappable+chargable battery designs are best imo.