While Lithium-ion (Li-ion) battery chemistry has become the emerging favorite among automakers, researchers at the Fraunhofer Institute for Chemical Technology (ICT) in Pfinztal, Germany are making a case for an alternative in the form of a new strain of enhanced-capacity redox flow batteries they are now developing. According to ICT engineer Jens Noack, "These batteries are based on fluid electrolytes. They can therefore be recharged at the gas station in a few minutes. The discharged electrolyte is simply pumped out and replaced with recharged fluid, for example, using a wind turbine or solar plant." Redox flow batteries in one form or another have been around for some time. Physically, they consist of two charged fluids that flow through porous-graphite felt electrodes separated by a membrane which permits protons to travel through it, thereby creating an electrical current. The twist in the Fraunhofer formulation is that it yields cells capable of storing four to five times the amount of energy potential in previous redox cells. That extra capacity will significantly extend the range of any vehicle to virtually equal that of a one fitted with a comparable Li-ion battery pack. Thus far, the development team has only produced a 1:10 scale operational prototype pictured here, but the next step will involve moving up to a 1:5 scale vehicle before fitting them into moving a full-size test car.
Photo credit: Hochschule für Angewandte Wissenschaften Ostfalia