AOL's Bradley Hasemeyer gets behind the wheel of BMW's first production electric vehicle, the BMW i3.
It is interesting to note the effect significant weight reduction has on range. Lets compare the BMW i3 to a Chevy Volt. The i3 has a battery capacity of 18.8 kWh with a maximum battery range of 190 km (120 miles) while the Volt battery is 16 kWh but achieves only 60 km (38 miles) - although in testing we routinely saw 80 km (50 miles) in EV mode.
The BMW i3 (without 150 kg range extender) has a curb weight of 1,195 kg, significantly less than the Chevy Volt with it's full sized 1.4 Lt 4 cyl at 1,715 kg. We found the same when comparing the Volt to the Kei class sized Mitsubishi iMiEV. Both have a 16 kWh battery but because the iMiEV curb weight is only 1,080 kg it gets approx double the range (155 km) of a Volt.
So less weigh equals more range per kWh of battery capacity.