A Toyota Corolla with a 1.8L engine requires 6.2 liters of gas to drive for 100 kilometers on a highway. But on city roads, it would require 7.9 liters of gas. A 2022 Ford F-150 requires 9.4 and 12.1 liters per 100 km for highway and city driving, respectively.
This was a lab test so regenerative braking didn’t factor, they just measured how much power they got from discharging the battery at full vs half load.
If you draw more power from a battery, you get more voltage drop. Voltage drop is a measure of the power lost (heat generated) within the battery and circuitry and it’s the internal resistance of the battery plus circuitry multiplied by the amps drawn. More power = more amps = more losses. This is why higher power applications use higher voltage battery packs because higher voltages mean fewer amps and smaller losses (power = amps x volts).