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Comment by idontwantthis | Hacker News Reader

If a Model 3 LR is 75kwh, and this is roughly 3x the range, and that takes roughly 20 minutes to go 10-80% at a supercharger then can anyone tell me what kind of hardware would be required to charge a 225kwh battery in the same time? Is it remotely feasible to build at least 100,000 of those chargers all over the world? Sounds like each one would need a gigantic capacitor or flywheel on site.

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Those chargers already exist. Tesla vehicles are limited by their 400v electrical system. Porsche already charges faster for longer via an 800v electrical system.

You also have to remember even 10-80 throttles SIGNIFICANTLY over that window as the battery fills. The higher speeds will run for longer on a larger battery assuming it is designed with sufficient cooling - one of the features of solid state batteries is supposed to be the ability to charge at higher rates for longer duration.

That’s a good point. So an hour long charge vs 30 minute charge with a SS battery could mean a 200 mile difference vs with a current battery it could be like 50 miles or less difference.

https://www.teslarati.com/tesla-v4-supercharger-speed-cable-...

Supposedly, V4 chargers are still currently capped at 250kW output (same as current L3 chargers), but are capable of upwards of 615 amps once more cars are capable of charging at 800 volts.

I don't know what building 100,000 of them will take, but it'll be a lot of metal for sure.

Cybertruck was confirmed to use 800V packs so they'll light up the network for use soon hopefully.

I wonder how much metal is tied up in gas tanks, gas trucks etc…

How often are you driving 1800 miles in a day.

Never, but I’m trying to understand what the experience would be like. If you charge at home then you are looking at like 2 days to fully charge at 240v. What I’m wondering is if these ranges are necessary or realistic for electric cars even if the storage tech is there. Maybe 4-500 miles is the max anyone would want regardless of how long charging could theoretically take if you were connected directly to a nuclear generator or something.

Only couple of times per year I drive those kind of distances myself, but I’d say the main benefit comes for “derating”. In other words, you can buy a 900 mile range car, and can travel 400 miles in Lapland winter (batteries don’t like cold, and self heating uses battery capacity). So you can drive to a place ~150miles away and back without thinking about destination charging, plus some reserve. This system would also last longer since you’re not forced a full charge cycle every day -> less aging.

Surely not an issue if you can have multiple cars. One can just have a diesel car for longer trips and have a small electric city car for everyday trips.

But why would you need to fully charge? What matters is charging enough in a day to cover your daily needs.

OK but then why have the battery capacity? It isn’t free in dollars or grams. Probably more likely we get smaller and smaller batteries and the range stays roughly constant.

Will be amazing for trucks and aircraft though. Truck stations on highways could potentially each have massive hookups or even their own solar and battery plants.

Because it covers trips long enough to reasonably do in a day. And if on average you are charging more than using, the battery will be at near full capacity most of the time. It eliminates range anxiety.

Truly autonomous cars could drive you cross country while you work, eat, sleep and consume entertainment all within the car. With those kinds of efficiencies it's pretty attractive regardless, but very short charging breaks would be even more attractive.

Replacing bus drivers with computers won't make them any more attractive as workspaces. There's a reason musicians don't actually like touring.

Sounds great. Sort of like a train, except with more traffic, no bathroom, more sudden acceleration and motion sickness, and no space to stand up and walk around.

A fully autonomous car charging robot would be a solution for that now.

Fall asleep in your van, car recharges every 300 miles via robot, 3 days later you are on the other coast.

Truly autonomous cars will go on strike and tell you meatbags to take a hike!

Usually people don't recharge their ICE vehicles daily.

Same applies to EVs.

70% of 225 kWh is 158 kWh. To transfer that much in 20 minutes would require 473 kW. The latest supercharger is rated at 250 kW, which is the limit for a 400 volt battery. So I'm going to say it would require a 800 volt battery and 500 kW charger.

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