EV battery tech compared

EV battery tech compared

by Wayne Cunningham

Lithium-ion battery packs are the current favorite for electriccars.

(Credit: NASA)

Battery technology presents the the biggest hurdle in going to electricvehicles. Current batteries don't provide the range offossil-fuel-powered vehicles. Worse, batteries take a lot longer torecharge than the time it takes to fill a 16-gallon tank withgasoline. But this isn't the end of the story, as batterytechnology is still being developed. For 100 years we got alongwith lead-acid batteries, but research has gone into high gear tolook at new battery compounds that might prove to be thebreakthrough that lets electric vehicle performance equal orsurpass that of gasoline-powered cars. Lithium ion is the current favoredchemistry, but other, more exotic compounds are being researched,such as zinc-air and lithium-polymer. Electric car enthusiast MikeThompson has compiled a chart of current battery and electricitystorage technologies, along with various specifications. The mostuseful number in the chart is watt-hours per kilogram (Wh/kg),which shows the energy density of the power source. The moreelectricity you can pack into a battery, the better range you willget for an electric car.

Click through for the full chart

(Credit: Mike Thompson)

According to the chart, research on lithium-polymer batteries showsthat they could hit 400 Wh/kg, the highest of any other technology.Zinc-air is second at 200 Wh/kg, while nickel-metal-hydride, usedin hybrid vehicles, is at 80 Wh/kg.