新型碱金属离子二次电池纳米结构电极材料的设计，调控及性能研究

开发具有高容量、长循环寿命、低成本的新型碱金属离子电池电极材料是能源存储领域的研究热点之一。如何克服低能量密度和较差的循环性能，是推进碱金属离子电池研究的关键科学问题。将传统电极材料二维化不仅能提高电化学活性表面积及储能活性中心浓度，而且能有效缩短离子扩散距离，从而提高电极材料的能量密度和功率密度；非晶微纳米材料没有晶体中存在的位错、晶界等，可有效缓解离子嵌入后体积膨胀产生的应力，提升了结构稳定性，进而可有效提高二次电池循环寿命；通过与三维交联网络及多孔结构的导电基底复合，可进一步优化离子和电子传输，提高电极材料的综合性能指标，获得高负载量、高能量密度，高功率密度，长循环寿命的新型二次电池电极材料。本项目的实施将系统地探究电极材料的二维化、非晶化、三维结构复合对新型碱金属离子电池的贡献，为新能源存储系统的发展提供实验和理论借鉴。

Developing new electrode materials for alkaline metal ion batteries with high capacity, long cycle life and low cost is one of the hotspots in the field of energy storage. How to improve the energy density and cycling performance of electrode materials is the key scientific problem to advance the research of alkaline metal ion batteries. When the bulk electrode materials were fabricated into 2D, not only their surface area and electrochemically active sites can be significantly enhanced, but also the solid-state ion diffusion distance can be effectively shortened, which would lead to high power density and energy density. The amorphous structure, which is loosely packing and possesses isotropic nature, can effectively accommodate the volume changes and alleviate the volume strain during ion insertion/extraction, maintaining the structural integrity and and thus greatly improving the cycle life of electrode materials. Integrating electrode materials with conductive substrate, which has 3D crosslinked network and porous structure, could further promote the ion and electron transport and improve the electrochemical performance of electrode materials. A combination of above three method would enable the construction of new type secondary batteries with high electrode materials loading , high energy density, high power density and long cycle life. This project will systematically investigate the contributions of 2D morphology, amorphous structure, and integration with 3D conductive substrate to the new alkaline metal ion batteries, providing experimental and theoretical insights for the development of new energy storage systems.