[Duncan]

Hi Bill
The keep the amps down is critical with lead acid - peukert!
But with lithium it's a bit (lot) less important

IMHO if I bought a 500 amp controller then I would expect it to operate with 500 amps and if it didn't I would be pissed off and send it back

I'm running my present controller at about 48% when driving around town - but that is to avoid losing traction and I am happy to re-set to 100% (just some switches on the dash) when I'm on the track

 

[Duncan]

I always thought the voltage to the motor was constant and the only variation was the amperage:

The controller effectively reduces the voltage until the motor takes the desired current

So 500amps motor at zero rpm is probably only 15v
So 15v motor x 500 amps motor = 150v battery x 50 amps battery

As the revs rise so does the Back EMF
at 1500 rpm and 500 amps the motor probably gives 45v Back EMF

so 15v + 45v = 60v x 500 motor amps = 150v battery x 200 amps battery

at 3000 rpm and 500 amps the motor probably gives 90v Back EMF

so 15v + 90v = 105v x 500 motor amps = 150v battery x 350 amps battery

Until you get to the point where the controller is on 100% and the battery voltage = motor voltage