柔性自支撑SiC/Si/C纳米复合负极材料的设计合成、组装及储锂性能研究

High-performance, low-cost flexible ion batteries (LIBs) have demonstrated great potential in future fields such as implantable and wearable electronics. Silicon is currently known to be a promising anode material that has the highest theoretical specific capacity. However, because of its large volume expansion during cycling usually leading to the silicon electrode pulverization, its performance (e.g. cycling and rate capability characteristics) is difficult to meet the practical application requirements. This project aims to design and fabricate the large area flexible free-standing SiC/Si/C nanoarray LIB anode material with reserved pore size by choosing the SiC/Si/C composite nanostructures as the research object, the carbon fabric as the substrate, the pyrolysis of the organic precursor as a nanowire synthesis method and the magnesium thermal reduction of silica and carbon coating as a silicon nanosructure based synthesis strategy. The project will systematically evaluate the the electrochemical energy storage mechanism of the flexible SiC/Si/C nanoarray composite structure, clarify the stability effect of the surface carbon coating and SiC nanostructures for the interfacial reaction of silicon, thus revealing what are the key factors and regulation approaches in determining the superior properties of the flexible SiC/Si/C nanoarray based LIBs. The implementation of the project will help solve the main problem involving the development of the silicon anode based LIBs. The relevant work will also provide some valuable basic data and key technologies for the fundamental research and fabrication of the flexible Si based LIBs.

高性能柔性离子电池(LIBs)在未来可植入性及可穿戴便携性电子产品等领域具有广阔的应用前景。硅是目前已知具有最高理论比容量的负极材料，然而由于其嵌锂时产生的巨大体积膨胀导致其循环稳定性较差，所以其性能尚难满足实际应用要求。本项目拟以SiC/Si/C复合纳米结构为研究对象，以碳布为衬底，以有机硅前驱体热解为SiC纳米阵列生长工艺，以SiO2镁热还原及碳包覆为硅基材料合成策略, 通过结构的精细控制与掺杂，实现具有预留孔径的大面积柔性自支撑SiC/Si/C纳米阵列锂离子电池负极材料的设计与制备。项目工作将系统评价柔性Si基纳米结构的电化学能量储存机理，阐明C/SiC纳米结构对硅界面反应的稳定机制，从而最终揭示决定Si负极材料性能优异的关键因素和调控途经等科学问题，项目的实施将有助于解决硅负极电池目前所遇到的主要问题，相关工作将为Si基LIBs的基础研究和器件化提供一定的基础数据和关键技术。

高性能柔性离子电池(LIBs)在未来可植入性及可穿戴便携性电子产品等领域具有广阔的应 用前景。硅是目前已知具有最高理论比容量的负极材料，然而由于其嵌锂时产生的巨大体积膨 胀导致其循环稳定性较差，所以其性能尚难满足实际应用要求。本项目以SiC/Si/C复合纳米结构为研究对象，以碳布为衬底，以有机硅前驱体热解为SiC纳米阵列生长工艺，以SiO2镁热还原及碳包覆为硅基材料合成策略, 通过结构的精细控制与掺杂，实现具有预留孔径的大面积柔性自支撑SiC/Si/C纳米阵列锂离子电池负极材料的设计与制备。项目系统评价了多级纳米阵列结构与电极性能等内在关联，探讨了柔性Si基纳米结构的电化学能量储存机理。课题进展4年来，发表论文5篇，其中SCI/EI论文5篇，授权发明专利3项。项目的实施将为Si基LIBs的基础研究和器件化提供一定的基 础数据和关键技术。