Process development and electrode manufacturing

Vacuum intensive mixer.
© Fraunhofer IFAM

Vacuum intensive mixer.

Roll-to-Roll coating unit.
© Fraunhofer IFAM

Roll-to-Roll coating unit.

Extruder in der Argon-Glovebox.
© Fraunhofer IFAM

Extruder in der Argon-Glovebox.

The performance of electrical energy storage is decisively influenced by the composition of the electrodes. According to the current state of technology, the manufacture occurs via the tape casting process, whereby a flowable mass consisting of active material, conductivity additives and binders is applied onto electrically conducting substrate materials. The process chain from the raw materials until the operational electrodes encompasses the process steps of mixing and dispersing, the wet application itself, the subsequent drying and, if necessary, calendering (compression). Each individual step is hereby adapted to the materials used and must also be optimized according to the performance targets as well as the demands placed on the electrode.

New materials and battery technologies often require the development of new manufacturing processes. To this end, we conduct research and development in the areas of:

  • Mixing and coating technology, including scale-up
  • Recipe development and paste formulation for the tape casting process (thick-film electrodes for double-layer capacitors and lithium-ion batteries, also silicon anodes for next-generation lithium-ion batteries
  • PVD/CVD process (physical and chemical vapor deposition): thin-film electrodes and shaping processes for nano-structured silicon anodes under inert conditions: composite electrodes for solid-state batteries, e.g. via extrusion
  • Manufacture of three-dimensional gas diffusion electrodes with adapted wetting characteristics for metal-air batteries.

The finishing standards are set according to the materials used and the type of query. Hereby, we can demonstrate both on the laboratory scale as well as the pilot scale.