[madaxe_again]

Air, rolling and other mechanical resistances are certainly part of the equation here, but the major driver of the decreased range at higher speeds is likely battery chemistry.

When you apply a load to a cell, the voltage sags. Heavier load, bigger sag. When a battery is operated at low voltage, it loses efficiency - the total power available decreases significantly. If you ever buy batteries for, say, building your own EV, you’ll pay a lot of attention to the C values - C1 is the capacity of the cell if it is discharged in 1 hour, C100 is the capacity at 100 hours, etc. - and there is a big difference between these values - it’s non-linear, and while the difference between C100 and C10 might be a 30% loss of available power, between C1 and C10 you’re closer to 50% - a 65% loss overall between C100 and C1.

Obviously in an EV C2-C10 are probably your most relevant numbers - but the difference in available power is significant over that range, and if you’re driving harder, putting more load on the battery, your range will be lower.

[aetherspawn]

The batteries have such large capacities that the C-rates are tiny. Tesla are well beyond the point where inefficiencies in battery contribute to as little as 1% of the total range.

Source: design engineer at EV company.

[hinkley]

Even during acceleration?

[aetherspawn]

The kind of acceleration that would cause it to be non-trivial is not the acceleration that you would use in normal driving unless you were very reckless.