The demand for elements for electrochemical storage technologies, such as lithium and vanadium, will increase in the future, making it necessary to rethink the raw materials used. In the search for a cost-effective and environmentally friendly battery technology, the zinc-air battery offers a promising alternative. Its use as a primary battery in the form of button cells is already established worldwide in hearing aids. The concept of a rechargeable zinc-air battery is based on a system through which potassium hydroxide solution flows and which contains a porous zinc electrode and a bifunctional gas diffusion electrode (GDE). The number of charging and discharging cycles is significantly influenced by the degradation of the electrodes. Dendrite formation often occurs on the zinc electrode during the charging process, which can be avoided by using the pulse charging method, among other things. Another challenge is the stability of the bifunctional GDE, as a loss of activity is caused by the catalyst being discharged from the electrode matrix, particularly during oxygen evolution.

As part of the project, suitable materials for the battery components were investigated and evaluated with regard to their long-term stability. The evaluation was carried out on the basis of tests in half and full cells. Furthermore, optimal operating conditions were worked out to enable the development and production of a 100 W demonstrator.

Further information: ZiLsicher: long life through structure