Hans Jürgen Seifert

Phase Reactions of Ceria in LPS SiC

The search for inert matrix nuclear fuel (IMF) materials to serve as matrix materials for reduction of plutonium inventories and transmutation of actinides has been underway globally for several years. The inert matrix materials are expected to accommodate compounds of plutonium, the minor actinides such as neptunium, americium, and curium and the long-lived fission products such as americium and cesium. Much of the recent effort has focused on silicon carbide which is an excellent candidate matrix material. It has a high thermal conductivity, high decomposition temperature and is stable against oxidation. It also has no undesirable phase changes with corresponding density changes and is stable to radiation (1, 2).

Laser in battery manufacturing: impact of intrinsic and artificial electrode porosity on chemical degradation and battery lifetime

The main goal is to develop an optimized three-dimensional (3D) cell design with improved electrochemical properties, which can be correlated to a characteristic lithium distribution along 3D micro-structures at different State-of-Health (SoH). 3D elemental mapping was applied for characterizing the whole electrode as function of SoH. It was demonstrated that fs-laser generated 3D architectures improves the battery performance regarding battery power and lifetime. It was quantitatively shown by laser-induced breakdown spectroscopy that 3D architectures act as attractor for lithium-ions. Furthermore, lateral intrinsic porosity variations were identified to be possible starting points for lithium plating and subsequent cell degradation. Results achieved from post-mortem studies of cells with laser structured electrodes (intrinsic and artificial porosity variation), and unstructured lithium-nickel-manganese-cobalt-oxide electrodes will be presented.