Electric motors are coming whether we want them or not. So let’s not pout, but instead celebrate the ways in which electric vehicles actually outperform their conventional internal combustion engine-driven counterparts.
gif: Engineering Explained/YouTube (Screengrabs)
Coming at us again on this fine fall afternoon is Jason Fenske of Engineering Explained with a short and sweet video detailing the main performance benefits of an electric car over a conventional one.
His main points are actually fairly straightforward. The first is that EVs produce peak torque at zero RPM, meaning acceleration figures tend to be stellar. It’s because of that low end torque (and just generally high torque output across a large rev range), low inertia, and high redlines that electric motors tend to be mated to single-speed gearboxes instead of complex transmissions. This means less weight in the drivetrain, more reliability, and no drivability or acceleration sacrifices associated with shifts.
His third point deals with throttle response. In particular, Jason talks about the physical limitations of center-pivoting round throttle plates, and the fact that rotating the throttle from five to 15 per cent yields an increased opening area of three times, whereas rotating the plate from 95 per cent to 100 per cent yields only a change in opening area of just over 1 per cent. With electric vehicles, though, calibrating the throttle with the power output is simply a matter of software, with Jason stating:
With an electric vehicle you can get exactly what you ask for with that throttle pedal because you can choose exactly how much power you want it to deliver at any given position, versus internal combustion engines which are more sensitive when you’re at low partial throttle.
The next point deals with the ability to use an electric motor to slow a vehicle down. By simply allowing the wheels to turn the motor (and use its inertia as drag), the forward motion of the car charges batteries instead of heating up brake rotors and pads. This means less fade and wear on the brakes, and even the ability to downsize calipers and rotors for less unsprung mass.
The last point, and the one I find most interesting, deals with the ability to flexibly package battery packs. Batteries can be oriented flat on the ground to allow for a low center of gravity, and they can be thin and of strange shapes because they neither require a fuel pump (which takes up space), nor do they require liquid to flow “downhill” to that pump. Plus, it’s not strange to have multiple battery locations (with a gas tank, you’d need a transfer pump between the multiple tanks). Yes, batteries are heavy, but they can be packaged in a way that helps maximise interior volume, and minimise the effect of that mass, yielding better handling.