Axial Flux Motors

A reader asks what I know about axial flux electric motors.  He says:

For some time, they have been recognized as having potential to reduce motor weight, cut costs, and improve motor efficiency, however there was a problem – how to lose unwanted heat.

An Oxford based company Yasa – recently bought by Mercedes-Benz has changed that by working out how to keep these motors cool. Their latest motor weighs 24 kg and is capable of delivering 590lb ft of torque, 480 hp of power, has reached 98% efficiency.

I have some familiarity with the subject, and I just watched a cool video on it, but I’m not a go-to person on axial vs. radial flux motors.  If there is some significant improvement in power/weight and/or torque/weight, that is a distinct advantage.

Keep in mind, however, that the total efficiency of charging and discharging batteries through our current-day electric motors is already very high, which means there is very little area for even theoretically possible improvement.