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by gus_massa 4839 days ago
I searched a little, but the information is confusing. The superchargers (apparently) use 90kW/480V=~190A. I want to highlight this: 190A!!!

A usual home connection can handle only up to ~10A, so 190A is a lot of current. To handle this you must use very thick wires. To charge faster you need move voltage or handle more current, probably you will need even thicker wires and to be careful with the safety measures.

Additionally, this experiment use only in a tiny lab sample. To increase the size and make a big model for a car, a lot of technical details will appear, for example how to handle all the heat that the battery produces during the charge / discharge cycles.
2 comments
frankus 4839 days ago
A typical new house in the US is wired for a 200A 240V circuit, or about 48kW.

By contrast the energy flux of a garden-variety gas pump is in the tens of megawatts.

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lostlogin 4839 days ago
Is that at the fuse box or the power point on the wall? Sorry if this is a silly question, it's just that here in NZ it's nowhere near that at the wall as the fuses are 10 amp ish.
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gus_massa 4839 days ago
The 200A are at the fuse box (in new houses, old houses may have less).

The wall sockets usually have 110V-15/20A connections. But there are some especial sockets with 240V-30/50A for special applications, like clothes dryers and electric ovens.

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lostlogin 4839 days ago
In our old house some genius used paper clips instead of fused wire in the (very old) fuse box. Not sure how I didn't die when I draped and extension lead in a puddle and got a shock. After I recovered I looked in the fuse box to see why the fuse didn't blow and found one fat paper clip over the gap. I'm not sure what current the box took, but I'm sure glad it wasn't 200Amps.
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kefka 4839 days ago
Seems pretty simple to me: You create a grid for your house, so it will always have electricity. You trickle charge a rack of graphine Supercaps for your house using mains. You dont need to send that power all at once.

The standard devices to handle passing from mains to battery should be able to be used.

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herdrick 4839 days ago
I think there's little issue with heat, as a major advantage of capacitors is efficiency in charging and discharging.
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