Electric motors and batteries have improved substantially over the past one hundred years, but today's much hyped electric cars have a range that is - at best - comparable to that of their predecessors at the beginning of the 20th century. Weight, comfort, speed and performance have eaten up any real progress.
And from a linked review of the upcoming Mitsubishi i-MIEV:
Under ideal conditions the i-MIEV has a rated range of 160 kilometers, or 100 miles. Conditions were not ideal. It was dark, so headlights were on. And at 27 degrees F, it was cold, so I had the heater on. Mitsubishi advises that using the heater cuts the maximum range exactly in half.
