Department Microstructure and Residual Stress Analysis

Battery materials

Electrode materials based on metals, such as aluminum or tin, could enable a significantly higher capacity than graphite, for example. In contrast, however, metal electrodes expand significantly when the lithium ions migrate, which leads to structural changes and thus to rapid “fatigue” of the material. We have produced porous metal electrodes and were able to prove that although the ions do not migrate into the pores, but rather between the pores in the material, the electrodes are nevertheless more stable than a simple metal foil. Metal foams are more expensive to produce than simple metal foils, but can still be produced relatively cheaply in large quantities, such as Ni foams, which are used in NiMH.