Submitted by bsolley on Mon, 2020-02-03 23:00
One of the biggest differences in range I see between a car with an ICE and an electric car is as you increase your traveling speed, your range in an electric car is dramatically reduced.
For example, if you get 300 miles per charge going 65mph, you likely only get 150 miles per charge traveling at 90mph. In an ICE, if you get 300 miles on a tank going 65mph, you likely get around 280 miles on a tank going 90mph.
I know there is a lot of math to account for. Drag coefficients at the different speeds, weight, grade of road and so on. What I was wondering, if you were to put a 2 speed transmission in an electric car, and have it shift at around 60mph, then aside from the additional torque gained, you’d also be running the motor at half speed (assuming the gear change was 2:1). Would the motor still draw the same amount of power as while the RPMs were reduced, the load was increased, or does the increased load not effect the draw as much? I’d assume that having that transmission would reduce the recharge rate of regenerative breaking as slowing would only spin the motor half as fast when it’s in second gear.