Structural Feature Design for Carbon Materials toward Sodium Storage: Insights and Prospects

Sodium-ion batteries are an attractive alternative to lithium-ion batteries due to the abundance and cost-effectiveness and are suitable for large-scale energy storage. Carbon materials, notable for their availability, economic viability, high capacity, and stability, stand out as potential anode materials. The sodium storage performance of carbon materials is inherently determined by their structural features. Manipulating these features is key to optimizing the storage behavior. This Perspective systematically evaluates the classification and structural distinctions of existing carbon-based materials for sodium-ion batteries, summarizing different sodium storage processes and electrochemical behaviors. Structural features are categorized into intrinsic (e.g., arrangement and distribution of carbon atoms) and extrinsic (e.g., heteroatoms). The sodium storage processes and behaviors associated with these features and the corresponding regulation strategies are explored in depth. Finally, the challenges and future directions for developing high-performance carbon anodes are proposed, aiming to provide actionable insights for advancing research and commercialization efforts.