Sodium ion battery soft and hard carbon negative electrode active material and preparation method and application thereof

• Main Authors: ZHUANG QINGFA, WEI LINJIAO, KONG FANHOU, WANG KAIWEN, LI SHULI, MA LINA, ZHANG QIU, ZHAO SUOQI
• Format: Patent
• Language: Chinese; English
• Published: 19.07.2024
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMISTRY; COMPOUNDS THEREOF; ELECTRICITY; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

The invention provides a sodium ion battery soft and hard carbon composite negative electrode active material as well as a preparation method and application thereof. The composite negative electrode active material is prepared from the following raw materials: asphaltene, carbonized reed straws, a pore forming agent and a sodium supplementing agent in a mass ratio of (30-50): (15-30): (10-20): (10-25). The carbonized reed straw is adopted as hard carbon and is wrapped by asphaltene soft carbon to form a core-shell structure, and in the presence of the pore forming agent and the sodium supplementing agent, the negative active material has the advantages of higher specific surface area and more active sites, and the assembled battery has the advantages of large specific capacity, small first-circle loss rate and the like. 本发明提供了一种钠离子电池软硬碳复合负极活性物质及其制备方法和应用，复合负极活性物质制备原料包括质量比为（30~50）：（15~30）：（10~20）：（10~25）的沥青质、炭化芦苇秸秆、造孔剂和补钠剂。本发明通过采用炭化芦苇秸秆作为硬碳，被沥青质软碳包裹在内，形成核壳结构，在造孔剂和补钠剂的存在下，使得负极活性物质具有较高比表面积，活性位点较多，组装的电池具有比容量大、首圈损