Preparation method of high-rate modified biomass hard carbon material

The invention relates to a preparation method of a high-magnification modified biomass hard carbon material, which comprises the following steps: pretreating a biomass material, and then carrying out two-stage carbonization, namely first-stage carbonization in a nitrogen atmosphere containing a small amount of oxygen and second-stage carbonization in the nitrogen atmosphere; and performing epoxidation and doping modification after carbonization. The preparation process is simple, the raw materials are low in price and easy to obtain, the obtained hard carbon material is excellent in electrochemical performance, especially the rate capability is obviously improved, and the requirements of current sodium ion batteries can be met. 本发明涉及一种高倍率改性生物质硬碳材料的制备方法，包括以下步骤：将生物质材料预处理后，进行两段式炭化，依次是在含有少量氧气的氮气气氛下炭化的第一段炭化，以及在氮气气氛下的第二段炭化；炭化后进行环氧化，以及掺杂改性。本发明制备工艺简单，原料价廉易得，所得硬碳材料电化学性能优异，特别是倍率性能得到了明显改善，能满足目前钠离子电池的需求。