Fast ion conductor

Electrical engineering

Physics

Nanotechnology

Electrode

Engineering physics

Interface (matter)

Solid-state

Endocrinology

Engineering

Composite material

Capillary action

Materials science

Lithium (medication)

Capillary number

Cathode

Quantum mechanics

Electrolyte

Electrochemistry

Medicine

Advanced Energy Materials

Solid‐state batteries (SSBs) currently attract great attention as a potentially safe electrochemical high‐energy storage concept. However, several issues still prevent SSBs from outperforming today's lithium‐ion batteries based on liquid electrolytes. One major challenge is related to the design of cathode active materials (CAMs) that are compatible with the superionic solid electrolytes (SEs) of interest. This perspective, gives a brief overview of the required properties and possible challenges for inorganic CAMs employed in SSBs, and describes state‐of‐the art solutions. In particular, the issue of tailoring CAMs is structured into challenges arising on the cathode‐, particle‐, and interface‐level, related to microstructural, (chemo‐)mechanical, and (electro‐)chemical interplay of CAMs with SEs, and finally guidelines for future CAM development for SSBs are proposed.

Designing Cathodes and Cathode Active Materials for Solid‐State Batteries