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Can electric cars on the highway emulate plane-to-plane refueling?

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Re: Can electric cars on the highway emulate plane-to-plane refueling?

#71

Post by ramshorns »

willis936 wrote: post #27
ashtonkem wrote: post #22

Earlier quoted context omitted.

Trains. The fact that long haul semi trucks are a thing is a failure of infrastructure. Edit: as some have pointed out, it’s more a failure of policy.

Trains are large and inflexible. Short of having a city-block resolution freight train network at every population center, you'll need something flexible for the last mile of delivery.

The inflexibility of trains can be a feature in some cases. People like to live near subway and commuter rail stations partly because they know the route and service level are much less likely to abruptly change on them than a bus route would.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#72

Post by jaclaz »

matz1 wrote: post #34
patall wrote: post #26

Can anyone explain what happened to battery swapping. A few years ago there was this Tesla show where they swapped three cars in the time it took to refuel a normal ICE automotive. But after that nothing happened. I know it is difficult to handle when you do not own the battery but I would guess 90% of private long distance trips are return trips, so you could swap batteries at your trusted former gas station every 2…

Probably the same reason why smartphone battery is not swappable. For various reason we don't have swappable smartphone battery even though it is technically much easier problem to solve.

It depends on the smartphone, there are still (very few) around that have one.

Beside the possible "planned obsolescence", I believe that the change was mostly because of waterproof or almost waterproof design, and (IMHO senseless) "let's make it thinner".

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#73

Post by leetcrew »

frosted-flakes wrote: post #68
ianai wrote: post #57

Earlier quoted context omitted.

I’d still like to be able to tow a battery behind me for extended trips. I don’t know how running the AC impacts range, I would like to know. Places with extreme weather and major population centers can make an otherwise short drive really taxing on resources through ac use or just being stuck in place for extended periods of time. Like how peak LV traffic can turn a 15 min drive into a 50 minute drive in 120f+ heat.…

That seems like a fantastic idea. This way, the car's internal battery can be smaller and lighter for day-to-day use (and therefore more efficient), and whenever longer range is needed you can just rent a fully-charged tow-a-battery, which you can swap out like propane tanks, or recharge yourself at home. These tow-a-batteries would work with any electric car with standard secure hook-ups. Since these batteries would…

by the time you've added enough protection (ie, extra mass and drag) to the towed battery, it seems like you would be pretty deep into diminishing returns. a large amount of the extra energy would be spent on moving the trailer itself.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#74

Post by Retric »

ravenstine wrote: post #69
Retric wrote: post #46

Earlier quoted context omitted.

It’s also a more complex and expensive. Swapping cellphone batteries means you need to own another battery which few people did once capacity increased. With cellphones people that want a swappable battery can just get an external battery pack but most people can simply recharge daily.

> Swapping cellphone batteries means you need to own another battery which few people did once capacity increased. That doesn't make sense to me. Sure, maybe you can't get an OEM battery, but I've owned cell phones in the last 5 years that I easily swapped out the old battery with an aftermarket battery for about $12. I think people have the ability to buy batteries. > With cellphones people that want a swappable bat…

Have you considered a battery case like: “Google Pixel 2 Battery Case, 4700mAh“ https://www.amazon.com/Rechargeable-External-Protective-Port...

From reviews that product is likely terrible, but I know people that are happy with their iPhone battery cases.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#75

Post by toss1 »

I've been thinking for years that fully-automated platooning / drafting should be a good option for self-driving cars. Run it via an app, cars make themselves available for drafting, others nearby sign up, they all line up and save energy. Could be a nice feature for Tesla, or a competitor, to augment the value of being in their network.

Obviously, this would rely on both self-driving and car-to-car communications to ensure simultaneous braking, acceleration, etc. to avoid accordion effect and chain-reaction collisions.

Charge-sharing as in this article could be a nice addition too. Also seems most plausible to automatically pay for shared charge in credits of some sort, or cash through the app. My biggest question is whether the shared charge would be sufficiently useful in comparison to the cost/maintenance of the extra moving parts. Seems like induction power&charging in sections of road could be more effective.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#76

Post by scottlocklin »

pjkundert wrote: post #2

One of the next obvious steps for self-driving vehicles is “flocking” or drafting; this is an almost trivial problem once two or more vehicles are autonomously locked within a few inches of each other.

Or you could just ride on a much less complicated, safer and more efficient railroad.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#77

Post by ianai »

leetcrew wrote: post #73
frosted-flakes wrote: post #68

Earlier quoted context omitted.

That seems like a fantastic idea. This way, the car's internal battery can be smaller and lighter for day-to-day use (and therefore more efficient), and whenever longer range is needed you can just rent a fully-charged tow-a-battery, which you can swap out like propane tanks, or recharge yourself at home. These tow-a-batteries would work with any electric car with standard secure hook-ups. Since these batteries would…

by the time you've added enough protection (ie, extra mass and drag) to the towed battery, it seems like you would be pretty deep into diminishing returns. a large amount of the extra energy would be spent on moving the trailer itself.

Not really. Yes batteries add lots of weight. But electric motors have lots of torque and are known to climb hills easily. Like how Tesla’s forthcoming truck can tow up to 14000 pounds. I’m not doing the calculus, but I suspect the power characteristics of electric motors more than make up for a towable battery.

Edit-here’s an article about a company doing this

https://electrek.co/2020/02/19/french-startup-proposes-batte...

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#78

Post by ianai »

frosted-flakes wrote: post #68
ianai wrote: post #57

Earlier quoted context omitted.

I’d still like to be able to tow a battery behind me for extended trips. I don’t know how running the AC impacts range, I would like to know. Places with extreme weather and major population centers can make an otherwise short drive really taxing on resources through ac use or just being stuck in place for extended periods of time. Like how peak LV traffic can turn a 15 min drive into a 50 minute drive in 120f+ heat.…

That seems like a fantastic idea. This way, the car's internal battery can be smaller and lighter for day-to-day use (and therefore more efficient), and whenever longer range is needed you can just rent a fully-charged tow-a-battery, which you can swap out like propane tanks, or recharge yourself at home. These tow-a-batteries would work with any electric car with standard secure hook-ups. Since these batteries would…

It also allows for faster retrofitting of old vehicles with new battery tech.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#79

Post by thrill »

jdofaz wrote: post #37
patall wrote: post #26

Can anyone explain what happened to battery swapping. A few years ago there was this Tesla show where they swapped three cars in the time it took to refuel a normal ICE automotive. But after that nothing happened. I know it is difficult to handle when you do not own the battery but I would guess 90% of private long distance trips are return trips, so you could swap batteries at your trusted former gas station every 2…

Increased capacity and high speed charging have made it not worth the cost/complexity. I've read the Rivian truck can have an additional battery dropped in the truck bed but I don't think it is something you can buy yet.

Correct-ish. Rivian has a patent for such an ability, but no announcement even of planned availability.

Continued battery improvements pretty much obviate any more complicated range extending efforts, IMO, other than perhaps road embedded magnetic chargers, which are fairly simple.

Re: Can electric cars on the highway emulate plane-to-plane refueling?

#80

Post by leetcrew »

ianai wrote: post #77
leetcrew wrote: post #73

Earlier quoted context omitted.

by the time you've added enough protection (ie, extra mass and drag) to the towed battery, it seems like you would be pretty deep into diminishing returns. a large amount of the extra energy would be spent on moving the trailer itself.

Not really. Yes batteries add lots of weight. But electric motors have lots of torque and are known to climb hills easily. Like how Tesla’s forthcoming truck can tow up to 14000 pounds. I’m not doing the calculus, but I suspect the power characteristics of electric motors more than make up for a towable battery. Edit-here’s an article about a company doing this https://electrek.co/2020/02/19/french-startup-proposes-b…

energy, not power. I'm sure the motors have enough torque to tow the battery, what I'm doubting is how efficiently that extra battery capacity gets converted to range.

as an aside, the cybertruck is (probably) pretty bad at towing. see this video for an interesting argument: https://www.youtube.com/watch?v=S4W-P5aCWJs

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