I noticed a piece on re thinking electric motors for cars ..https://www.bbc.co.uk/news/business-49958457
seriously I thought each wheel was already electrified but must have got ahead of myself!
What do you guys think?
First problem is unsprung weight which should always be as low as possible.
Second problem is their argument against themselves. They rightly say ultra high rotation speed is best for power to weight ratio, but the wheels rotate far more slowly than current e-car motors. The only solution to that is in-wheel reduction gearing, which with the associated oil lubrication would raise the unsprung wheel weight even further.
Third problem is the safety aspect. My e-car for example has a 400 volt drive system, which is safely contained well within the vehicle structure. Having these necessarily high voltages at each wheel in the event of an accident presents a huge danger to all around, including any vehicle collided with, possibly electrocuting the occupants.
Their forecast that electric motors in ten years time will be radically different from today is simply wrong. We've been developing electric traction motors for land transport in trains and trams for over a century now and they are already very refined.
The best place for the motors in most e-cars is where they are at present, at the axles as part of the sprung mass. Moderate voltage in-wheel motors could have an application in slower small urban transit vehicles.
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