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I wonder which will be more practical. Here's an inductive charger using a Roomba-like robot to get itself into position.

Elon said a couple of years ago that Tesla would have a snake robot plug-in system, but it appears to be typical vaporware.

Question is, which one would be more practical. I could see a fairly simple robot that could plug in my at-home connector if I were energetic enough to make it and simultaneously lazy enough to think it worth the effort. Would be nice to be able to just drive into the garage, though. :unsure:
 

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Inductive charging systems often have 1) low power and 2) pretty high losses. Nobody cares when it's a phone charger but they'll care a lot when it's a 10kW EV charger.
Maybe, but they are advertising that it's not that bad. Maybe it depends on how close you can get the surfaces, which could be zero inches--direct contact--if the Roomba lifted it up against the car when in position.
 

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Maybe, but they are advertising that it's not that bad. Maybe it depends on how close you can get the surfaces, which could be zero inches--direct contact--if the Roomba lifted it up against the car when in position.
Alignment is also important, as a misaligned setup will produce more losses too. This is part of the reason Apple added magnets to help align the coils better, and Qi2 will include those same improvements. But with Qi, the best numbers I've seen suggest around 70% efficiency. Perfect alignment isn't going to help those numbers a huge amount, but it does mean you'll get closer to the maximum efficiency regularly.

70% efficiency isn't bad for wireless but when comparing to the 95% efficiency of the ID.4 plugged into an L2 charger that can provide 11kW, it's the difference between 7.7kW or 10.5kW reaching the battery, or over 30% faster. It's also the difference between needing 81kWh or 110kWh to fully charge a battery from 0-100%, at an extra cost of 29kWh.

That 29kWh could power my house for a couple of days...
 

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Alignment is also important, as a misaligned setup will produce more losses too. This is part of the reason Apple added magnets to help align the coils better, and Qi2 will include those same improvements. But with Qi, the best numbers I've seen suggest around 70% efficiency. Perfect alignment isn't going to help those numbers a huge amount, but it does mean you'll get closer to the maximum efficiency regularly.

70% efficiency isn't bad for wireless but when comparing to the 95% efficiency of the ID.4 plugged into an L2 charger that can provide 11kW, it's the difference between 7.7kW or 10.5kW reaching the battery, or over 30% faster. It's also the difference between needing 81kWh or 110kWh to fully charge a battery from 0-100%, at an extra cost of 29kWh.

That 29kWh could power my house for a couple of days...
Someone was selling a magnetic induction charging system for the Chevy Volt; they were quoting efficiency numbers in the high 80s and that matched pretty well with my engineering spidey sense.
 
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