Since the late 1800s, the primary impediment to the adoption of electric vehicles has been battery technology. And while the technology has advanced by leaps and bounds in the last decade or two (compare your cell phone with one from the early 90s), with a threefold improvement in energy density and more than an order of magnitude improvement in power density, it still lags behind gasoline.
Some have argued that current technology is sufficient — that the ability to drive 1 1/2 hours to 3 hours nonstop is good enough for the overwhelming majority of trips, and that paired with a range extender, rapid chargers, or battery swapping, you have a viable means of replacing the gasoline car. However, there still is a great deal of pressure to get electric vehicle range up to that of gasoline.
