The Fraunhofer Institute is developing redox flow batteries for electric cars.
Wayne Cunningham reviews cars and writes about automotive technology for CNET's Roadshow. Prior to the automotive beat, he covered spyware, Web building technologies, and computer hardware. He began covering technology and the Web in 1994 as an editor of The Net magazine.
See full bio
Imagine that you're driving your future electric car down the road, and it gives you a low battery warning. What do you do? Instead of spending a few hours at a recharging station, new battery technology being developed by the Fraunhofer Institute in Germany would let you pull into a service station and refill the battery with an electrolytic liquid.
The Fraunhofer Institute is using a redox flow battery, a type of cell that uses two electrolytic fluids exchanging protons through a membrane. This process generates electricity. Although this type of battery isn't new, the Fraunhofer Institute improved the energy density, making it equivalent to that of a lithium ion battery.
In production cars such as the Tesla Roadster, the lithium ion battery pack requires almost four hours from a quick charger to go about 200 miles. A redox flow battery service station would pump out the discharged electrolytic fluid from your car's battery, replacing it with charged fluid, most likely in a matter of minutes. Instead of getting new shipments of charged fluid, similar to how current service stations rely on tankers full of gasoline, the station could merely recharge the fluid on its premises, even using solar cells or a wind turbine.