AC charging past 80% energy waste ?!

[BigApple]

Wanted to see if anyone out there knows
On DC charging it is straight forward.
The closer you are when charging to 100% SoC the lesser you car will draw from the charging station. But how is it with AC charging ?
I ask to know if you actually waste AC energy when you charge your car past the 80% SoC. On DC it won’t waste as it is same current. How about AC ? Will the 40-50 amps still be drawn from the house power while the car gets less kWh charged ?
It seems there is less energy lost during DC charging while on AC it seems you loose more. Wondering if anyone knows how that behaves ? Thank you.
If there is a bigger AC energy waste by charging past the 80% would be helpful to know. I usually don’t, to prolong the Batterie life. But I think it would be helpful to know in case I needed 100% SoC.
Thank you.

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[ColdCase]

Just want to mention that the current isn't constant, just the voltage.

Watts is voltage times current. Since the voltage is constant in either case, as the kW charge indicated drops, the current drops. In other words the current isn't a constant 40-50 amps. It will drop as the power delivered drops.

AC charging will always be less efficient than DC as the battery needs DC to charge and there is some conversion loss in on board car charger when it converts AC to DC.

Otherwise, from a battery point of view, its all DC charging, just at different rates. Dunno off hand if charging the battery at a say 80 kW rate over a short period is more or less efficient than charging at 8 kW over a longer time.

So current is watts divided by voltage.

9 kW from a typical 240V level 2 source is 37.5 amps

80 kW from a typical 300V DC source is 266 amps
When it drops off to 60kW indicated, the current drops to 200 amps