[elihu]

A 5% efficiency gain might be a big deal when it comes to motor heat. Electric motors tend to be around 85-90% efficient or so, and if you can get the motor from, say, 85% efficient to 90% efficient, that might translate to a one-third reduction in waste heat.

[outworlder]

> that might translate to a one-third reduction in waste heat.

Is that a big deal, though, compared to battery heat? Or is it in the context of a race scenario?

[amluto]

Speculation, since I’m not an expert:

The battery is big, so it has high thermal mass and lots of area for cooling. The motor is small. Motors can also easily be thermally limited. A permanent magnet motor that overheats will demagnetize and be destroyed. Induction motors and other non-permanent-magnet motors are less sensitive, but resistance goes up and metals and glues soften at higher temperature.

[elihu]

My understanding is that getting rid of waste heat is one of the main factors that limits how much power you can get out of an electric motor for any length of time. Less heat means you can get up a long steep hill without overheating (or causing the electronics to back off on the motor amperage to avoid damage).