> That’s a some 9kW lost on a 80kW battery

It's about the same as wired AC charging. There are always charging losses:

https://insideevs.com/features/711659/ev-charger-efficiency-...

> That’s a some 9kW lost on a 80kW battery.

*kWh

Using the right units is important.

I keep wondering why a robot-vacuum-charging-dock style solution hasn't materialized. We've seen to robotic arm demos but those aren't around because they are overkill for the task. But something that the car autonomously and accurately docks into and attaches from either the front fascia or underneath. Same charging standard but with a more forgiving connector design that guides and locks in.

Charging rate of 11 kW, with efficiency of about 90%, means that the charger sucks around 12.2 kW of power from the grid, of which 1.2 kW is continually lost*, and only 11 kW is effectively being stored in the battery at any point in time.

I don't understand the mention about battery capacity (80 kWh, which would translate to around 7½ hours of charging at 11 kW, if a battery could charge at a uniform rate) or where the "9 kW lost" figure comes from.

*Which is probably useful to melt snow above the device, when installed outdoors on cold climates.

It will still be 90% efficient regardless of who uses it. In fact if it is used more, the total losses will be higher.

(Some of this becomes clearer when you have a feeling for the units: kW is a measurement of power, not energy)

> not to charge fully at home, e.g overnight, which is what Porsche aims for.

Wouldn't an overnight (usually cheaper) 10+ hour charge be a great use for (slow) 11 kW charging?

you think Porsche owners give a shit about efficiency? Laughable at best.

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