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Comment by guimarin | Hacker News Reader

I still don't understand why people think this will do anything for electric cars. The bottleneck is how long it takes to charge your car. If you have a 60KW/hr pack, you can only charge it so fast with a 110v/20amp jack (for the sake of pie in the sky projections assume 50% charging efficiency between charger and battery). Period the end. you could always do 220v/30amps, or 208v/30amps/3phase. or 440v/1000amps. the tradeoff is in how many idiots electrocute themselves. It never ceases to amaze me how people don't get this simple simple fact. It's like saying that you can fill up a swimming pool faster because you've made a sturdier garden hose.

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That's pretty short-sighted Mike. First, a 10x battery boost would mean you don't have to recharge the car fully over a week.

This is also a boon for battery swapping stations which are bein built in Israel and other places.

lol. it's like you're trying to troll me. #5,612,606.

He's talking about this patent, by the way, which I know he made: http://www.patents.com/us-5612606.html

But that patent's going to be expired by the time these batteries are ready.

Shai Agassi's patent #7,993,155 for a charging connector even references this one. Doesn't look like they consider it a problem.

well i'm also talking about how the battery swap stations being built in israel and other places, are being built by Better Place. Which in turn was started by Shai Agassi, who was never approached by my former company about being an investor in this technology. and consequently has to operate outside of zones that issue/respect patents.

Most homes have 220v devices that people use safely every day without electrocuting themselves. If your really concerned about how fast they charge just run a second line and wow it's charging twice as fast. On top of that decent charging stations are well over 90% efficient much worse than that and they start dumping a lot of heat which harms the battery. 3 * 220v/50amps * 90% efficiency will fill that 60KW/hr pack right quick.

So sure, it takes a long time to fill the tank using a normal extension cord, but then again most people can't refill their gas powered car at home so it's still a net win.

You don't say? they have washing machines that they plug and unplug every single day? 2 lines, why didn't I think of that. Brilliant! It's so cheap to build a 3-phase charger at 400V at 32 amps so you can charge a 20kWh pack in 2 hours (60kWh in 6!). Everyone should do it. It makes perfect economic sense! It's exactly like gas. Everytime I want to fill up my car, I sit at the pump for 6 hours. But this battery tech will change all that. Yes, now that we have better longer-lasting batteries, it won't take so long to fill up. Nevermind that there is an ENORMOUS demand for batteries, that these are at least a decade away from production, and thusly economies of scale are already reached. But sure, continue to tell me the same old bullshit. eventually someone will believe it, and we'll all start living in the future.

I guess the reason that the US thinks that 220V is unsafe is the plug socket design?

Could you adopt a new plug for existing 220V appliances (AIUI you have 220v for washing machines & dryers etc?). Then over time you could migrate all your plugs to the new sockets and voilá - the whole world gets to boil a kettle in a reasonable amount of time.

Would still take 7 hours to charge your 20kWh car battery, natch.

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