Cryogenic electron microscopy workflows for the characterization of electrochemical interfaces and interphases in batteries

Fundamental understanding of (electro-)chemical processes occurring in batteries down to an atomic level is essential to further improve the performance of commercialized battery technologies and to establish novel cell chemistries. Transmission electron microscopy techniques are well-suited for highly localized structural and chemical analysis, but many electrode materials and their corresponding electrode/electrolyte interfaces and interphases are sensitive towards ambient conditions and/or the high energy electron beam. This necessitates cryogenic cooling of the specimen during sample preparation, transfer, and/or imaging. Here, we highlight the major experimental workflows derived from sample-specific requirements, which vary in complexity and infrastructural requirements. The purpose of this Perspective is to give a comprehensive guideline on both the opportunities and requirements of cryogenic (transmission) electron microscopy to analyze materials/phenomenon-specific questions relevant to battery research.