Recent advances in characterization of rechargeable battery materials via scanning probe microscopy

Numerous challenges exist in fully understanding current lithium-ion battery (LIB) technology and commercializing "beyond LIBs" which could help support reaching net-zero carbon emissions in the future. These highly complex systems undergo many dynamic processes at different time and length scales, including ion conduction, interphase formation, and degradation, that can be challenging to capture with traditional characterization tools. As a result, scanning probe microscopy (SPM) has become an invaluable platform for enhancing the understanding of these complex and important processes. SPM can be used to obtain topographical, mechanical, electrical, and electrochemical information on a wide range of materials in a variety of environments, including in situ and operando studies. In this perspective, we briefly describe the operating principles of LIBs and a number of relevant SPM techniques, followed by presenting recent highlights of SPM's unique capabilities as a characterization tool for battery systems. Finally, we offer recommendations for the improvement of SPM studies of battery materials as well as future outlooks.