Henning Weinrich


Cathodes for resource-efficient metal-air batteries

Scheme of a metal-air battery Copyright: Henning Weinrich

The increasing use of renewable energy sources like solar and wind energy requires the integration of energy storage devices into the stationary electric grid at a progressive rate to maintain a stable mains operation during fluctuating feed-in of electric current. From an economic point of view it is although of great interest to store as much energy as possible in an efficient and cost-effective way. In this context one promising class of energy storage devices are secondary metal-air batteries which may attain practical energy densities up to 3 kWh·kg-1. This value represents an energy density which is about 10x higher than the energy density of current lithium-ion batteries. However, as a matter of different facts metal-air batteries cannot be recharged electrically over many cycles yet and are not commercialized as secondary batteries.

According to the great potential of secondary metal-air batteries but still insufficient capacity the aim of this PhD thesis consists in the improvement of metal-air battery performance. With regard to an increased cyclability of the batteries the efficiency of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) at the cathode will be improved. For this purpose both the microstructure of the cathode as well as the processing and kind of necessary ORR- and OER-catalysts will be optimized to provide a resource-efficient secondary metal-air battery.