What you are seeing is the motor which is an AC motor. The center of it is a simple gearbox. Because an electric motor can be throttled and can run up to a speed far beyond what a gasoline driven engine can run, there doesn't need to be a transmission. Then to the other side is a three phase tri-pole inverter which converts the DC battery power into AC power to run the motor. (You may have a something similar which you use to power a laptop or other A/C using devices in your vehicle, but this one is on a whole different scale.) This How it's Made Dream Cars episode (S02E10) explains how everything is put together.

What you are seeing is the motor which is an AC motor. The center of it is a simple gearbox. Because an electric motor can be throttled and can run up to a speed far beyond what a gasoline driven engine can run, there doesn't need to be a transmission. Then to the other side is a three phase tri-pole inverter which converts the DC battery power into AC power to run the motor. (You may have something similar which you use to power a laptop or other A/C using devices in your vehicle, but this one is on a whole different scale.) This How it's Made Dream Cars episode (S02E10) explains how everything is put together.