Hard carbon (HC) is the state‐of‐the‐art anode material for sodium‐ion batteries due to its excellent overall performance, wide availability, and relatively low cost. Recently, tremendous effort has been invested to elucidate the sodium storage mechanism in HC, and to explore synthetic approaches that can enhance the performance and lower the cost. However, disagreements remain in the field, particularly on the fundamental questions of ion transfer and storage and the ideal HC structure for high performance. This Minireview aims to provide an analysis and summary of the theoretical limitations of HC, discrepancies in the storage mechanism, and methods to improve the performance. Finally, future research on developing ideal structured HCs, advanced electrolytes, and optimized electrolyte–electrode interphases are proposed on the basis of recent progress.

中文翻译：

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硬碳作为钠离子电池阳极：进展与挑战

硬碳（HC）是钠离子电池的最先进阳极材料，因为它具有出色的整体性能，广泛的可用性以及相对较低的成本。最近，人们投入了巨大的努力来阐明HC中的钠存储机制，并探索可以提高性能和降低成本的合成方法。但是，在该领域仍然存在分歧，特别是在离子转移和存储的基本问题以及高性能的理想HC结构方面。本Minireview旨在对HC的理论局限性，存储机制的差异以及提高性能的方法进行分析和总结。最后，关于开发理想的结构HC，高级电解质，