We may still have many things we can do to improve the efficiency, but the efficiency pretty close to 100% already, with Tesla hitting around 94% in their motors. So not a lot of room there. But of course there is still room to shrink the motors, make the motors lighter, make the motors have more power that can be sustained over a broader range of speeds, etc.

But the motors are already not super heavy or big by automotive standards, so the net benefit of those improvements are not so great, at least in normal sized cars. The biggest thing I would like improved is the range of speeds at which peak power can be sustained. In my model 3, I have around 500hp at low speeds, but it starts tapering off after 40mph or so. The model S plaid reduces this tapering by using more motors, which allows different gearing so the optimum motor speed is hit at a higher vehicle speed, and a bit more voltage.

The thing about improving up from 94% is, we may not magically double the power savings. But say, going from 94% to 97% may cut the waste heat in half, which means you can suddenly run the same size motor with twice the current without melting it down. So there are some nice benefits possible there.

Look at things like the "microstepper drivers" and "inverter heat pumps" too; its not just that we're getting more motor options, we're getting better at switching and shaping rich, chunky amps with little cheap chips of glass. That's opening up all sorts of capabilities that were fairy tale expensive before if they were possible at all.

Yes, tapping that regenerative power will be a major step towards wheels directly geared to a clutchless motor which will then eliminate drive train losses. And I think alot of motors dont do regen in any major way yet.

The problem with regen is its too spiky and lithium ion charging doesnt like that unlike lead acid which can handle it, but using multiple battery options is becoming more normal. Cars fitted with stop start technology typically have an additional battery using either the newer cheaper Enhanced Cyclic Mat (ECM) batteries and the more older more expensive Absorbent Glass Mat (AGM) batteries, but they work.

Hear hear! I think we're just beginning to understand how much we can use smart chips and intelligent switching to improve performance. All you need to do is look at one of the old motors with brushes to realize how far we've come.

" dont think we are even scraping the surface when it comes to electrical motor efficiency"

It's not uncommon for electric motors to be well over 90% efficient, and approach 95% or better within their ideal RPM range.

Windings are just part of the design; there's the lamination of the rotor and its materials, and the arrangement of the magnets (for example, halbach arrays.)