Review for Advanced NMR Characterization of Carbon‐Based and Metal Anodes in Sodium Batteries

Battery performance is highly related to the intrinsic properties of battery materials. To develop commercial anode electrode materials for advanced sodium‐based batteries, it is crucial to understand whose fundamental issues including compositions and structure of the bulk and interface, dynamics and electrochemical reactions during cycling. The key for present and ongoing success of carbon‐based and sodium metal anode is to overcome an intrinsic challenge associated with transport and storage of ions and complicated interface activities, especially for the sodiation process with associated risk of dendrite. Advanced Nuclear Magnetic Resonance (NMR) technique has unique advantages in characterizing the local or microstructure of anode electrode materials and their interfacial evolutions down to the atomic level by a noninvasive and nondestructive manner. In this review, an overview is provided of the recent advances in understanding the fundamental issues of carbon based and sodium metal anode materials using advanced NMR approaches. Here, latest advancements of NMR are presented for applications in characterizing structures and dynamics of anode electrode material as well as their interfacial evolutions. Finally, the prospect and limitation of NMR techniques in batteries research will be highlighted, thereby paving the way for accelerating the development of next generation sodium batteries. One of key issue in SIBs is the development and characterization of anodes. In this review, it is aimed to provide an overview of how the ssNMR approaches can help us better understand the underlying mechanisms, dynamics, and structures of sodium anodes by its unique and innovative role. The advancements of ssNMR used in sodium anode research are also highlighted.