钠电池常用负极材料是什么？

What is the commonly used anode material for Sodium-ion Battery?    

当前规模化商用钠离子电池的唯一主流负极材料为硬碳，也是目前产业化适配性最好、性价比最高、技术最成熟的负极材料，暂无其他材料可以大规模替代。硬碳是一种非石墨化碳材料，内部拥有大量大小适配钠离子的微孔、介孔结构，完美适配大半径钠离子的嵌入和存储，解决了传统石墨材料无法储钠的核心难题。同时，硬碳具备储钠容量高、结构稳定、循环衰减慢、生产成本低廉、适配性强等多重优势，能够匹配三大主流正极材料体系，兼顾动力和储能场景需求，是支撑钠电池快速产业化的核心材料之一。软碳、复合材料等新型负极仍在研发迭代，尚未商用。

At present, the only mainstream anode material for large-scale commercial Sodium-ion Battery is hard carbon, which is also the anode material with the best industrial adaptability, the highest cost performance and the most mature technology at present, and no other material can be used for large-scale replacement. Hard carbon is a kind of non-graphitized carbon material, which has a large number of micropore and mesopore structures with sizes suitable for sodium ions, which perfectly adapts to the intercalation and storage of large-radius sodium ions, and solves the core problem that traditional graphite materials cannot store sodium. At the same time, hard carbon has many advantages such as high sodium storage capacity, stable structure, slow cycle attenuation, low production cost and strong adaptability, which can match the three mainstream cathode material systems and take into account the needs of both power and energy storage scenarios, and is one of the core materials supporting the rapid industrialization of sodium batteries. New anodes such as soft carbon and composite materials are still in the research and development iteration stage and have not yet been commercialized.