Peukert’s Coefficient: 

Battery nominal cell capacity is quoted at a constant discharge current rate for 5 hours.

Example:  A 100 Ah battery will discharge 20 amps for a period of 5 hours ( 20 A x 5h = 100Ah)

In service the discharge current varies depending on the demand from the motor.

 Fig. 1 shows how a 100Ah battery varies with intermittent discharge rates. 

The curve shows how the effective battery capacity reduces with increased discharge current.

Example:   100Ah battery capacity at 20A discharge rate, but has an effective capacity of only 45Ah at 200A discharge rate.

The equation to this curve is known as Peukerts equation. 

Hence you can instantly see the effect on range of reducing the demand by throttling back or using less power by having a good shape and low rolling resistance.

You can see that there is not only a gain by reducing the discharge amps but also the effective battery capacity increases.  This must be used with a little common sense, as at very low current you will not go anywhere and there may be a decrease in the drive / motor efficiency.