(417d) Investigations of New Materials for Rechargeable Zinc-Air Batteries

The investigations aim to develop and optimise rechargeable zinc-air batteries. Zinc-air cells are characterised by high specific energy density, inexpensive materials and good environmental compatibility. The necessary increase in cycle stability of zinc air cells will be realized by using innovative materials for all components, which are capable to avoid or to minimise the degradation and deactivation.

The characterisation of materials in half-cell tests focuses on the development and optimisation of the electrodes, the investigation of various production procedures and the influence of electrode and electrolyte composition on the rechargeability of the zinc-air cell. The investigated air electrodes consist of the gas diffusion layer, prepared by the calendar rolling technique and the active layer which contains the catalyst for both, oxygen reduction and evolution. The two layers are combined with the current collector made of titanium mesh. Carbon nanofibers are used in both layers of the electrode. Polytetrafluoroethylene (PTFE) is added as hydrophobic component and La0,6Ca0,4CoO3 perovskite is used as catalyst in the active layer. The measurements are performed in half cell tests using 3.2 M KOH as electrolyte.