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Comment by blunte | Hacker News Reader

I'm really looking forward to these, but I wonder about the charge time. Even if/when batteries can take much higher charge input, the power source and underlying grid has to be able to provide that greatly increased output safely.

If the Tesla Model X 100D can charge to 170 miles range in 30 minutes with 480v 300A power source, the charging station for this Toyota would need to be ????v and ????A (many multiples of the Tesla). I don't think I want to be anywhere near that if something goes wrong. The solid state battery may not fail, but something else might... That's an electrical explosion with deadly power.

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Assuming that people aren’t charging 10p% of the time, I would have thought that a charging station would itself be battery powered, dumping its energy at high speed into a car and charging more slowly from the grid?

That would reduce strain on the grid while providing high charging times to users.

I once had a discussion with my friends about this. We ended up concluding that liquid fuel is so power-dense that it would take building a new 110kV transmission line to replace three fuel tank trucks a day.

I suspect that swappable batteries are the future, at least partly, e.g. for big trucks. Not only do they help to refuel in minutes; transporting them to an installation with high-power electrical infrastructure could be the only way to efficiently recharge them.

This is something I've thought about as well. Someone's going to eventually build a big business with a power delivery company. They bring their battery-laden van to your location and charge your vehicle, either for emergency assistance or for scheduled charging.

Or, you have some special trains (not in the US of course, since trains are an evil liberal vehicle) where your car is parked for some journey and charged at the same time; you take a nice break, get some food, visit the WC, and then take your car at a stop at the next major city.

Lastly there's the battery swap option, which is probably the best overall solution. Batteries get mass transported, and a smart logistics system ensures that everyone has power when and where they need it.

It says it recharges in ten minutes. Let’s see.

I think they're saying that the very short charge time seems potentially dangerous given the amount of current involved.

right every charger would be like a high voltage substation, of course people have complained about the safety potential of every new innovation and for the most part they're tamed. Seems likely that people dying from stupid drivers will far exceed deaths from the charging infrastructure even of hydrogen or this very high current.

Have there been any electrical accidents from current superchargers, etc.?

I have been following Tesla for many years and have heard of lots of story about people getting hurt with Tesla. I have never heard of such a case during everyday operations of a supercharger.

Likely somewhere somebody has died during installation of these stations but I have never heard of it.

My guess would be the death rate are about as high as installing any electrical system with high current.

Yeah, I did a quick Google for supercharger electrical accidents, and I can’t really find any: I suspect you’re more likely to see a gas station fire than an accident at a fast charger.

there are around 200 times more gas stations currently than fast chargers so absolutely. The question that matters is if you replaced all of those with fast chargers would the accidents at fast chargers be worse than gas station accidents. I am not saying that is not the case and also like gas stations they will get safer over time.

Probably the larger concern (or at least as large) would be that the current electrical grid couldn't handle that kind of load if a significant number of people started driving these quick charge electric cars which require these large currents. Likely we'd need to slow down the charging anyway to accommodate the limitations of the power grid.

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