Amorphous Carbon Layers for Longer-Lasting Batteries

Demand for more powerful and lighter battery systems is growing. Batteries with high energy density and long service life are in particular demand for electric mobility, aerospace, and stationary energy storage. The Fraunhofer Institute for Thin Film and Surface Technology IST is therefore collaborating with the Fraunhofer USA Center Midwest (CMW) to explore new approaches for improving the performance and lifespan of future battery systems. One promising approach involves lithium-metal anodes, in which lithium itself serves as the active anode material and, due to its high specific capacity, enables battery cells with potentially higher energy density. In the research project “LIMAC – Amorphous Carbon Interlayers for Reliable Lithium-Metal Battery Cells,” thin amorphous carbon interlayers are used for this purpose.

Laser-Arc-PVD Produces Carbon Interlayers

The central question is whether the carbon layers can stabilize the interface between the lithium-metal anode and the (solid) electrolyte, thereby contributing to more reliable and longer-lasting battery cells. To this end, thin amorphous carbon layers will be developed and deposited onto copper current collectors using a laser-arc PVD process. The coated materials will then be tested in battery cells and compared with reference cells. In addition to technical performance, the project also considers environmental aspects and the future scalability to larger cell formats. Using a life cycle assessment, relevant material and energy flows as well as environmental impacts will be examined, and at the same time, a concept for scaling the technology to larger pouch cells will be developed.