Beyond Conventional Coatings: Melt‐Infiltration of Antiperovskites for High‐Voltage All‐Solid‐State Batteries

Solid-state batteries (SSBs) have emerged as promising candidates for next-generation energy-storage solutions, particularly for electric vehicle applications. To overcome challenges related to interfacial stability and electro-chemo-mechanical degradation during operation, the development of protective surface coatings for cathode active materials (CAMs) is essential. Lithium-rich antiperovskites (LiRAPs) exhibit a unique set of beneficial properties, notably a high ionic partial conductivity at room temperature, enabling the deployment of advanced coating techniques via cost-effective and environmentally benign methods. In the present work, the application of LiRAP coatings to a layered Ni-rich CAM, namely LiNi0.85Co0. 1Mn0.05O2 (NCM85), is examined, utilizing a low-temperature and solvent-free approach. The effectiveness of the procedure is evaluated through microscopy analyses and electrochemical performance assessments. The results demonstrate a significant improvement in cyclability, highlighting the potential of LiRAP-based surface coatings for enhancing the performance and longevity of high-capacity cathodes in SSB systems.