三维多级微纳结构富锂锰基正极材料的离子液体辅助可控制备与电化学性能研究

动力型锂离子电池是关系到能源战略的课题，是锂离子电池的重要发展方向。本项目针对高容量高电压富锂锰基正极材料电子导电性差和锂离子扩散慢的缺点，提出采用离子液体辅助法构建高效电子/离子导电网络——三维多级微纳结构来对富锂锰基材料进行改性。利用离子液体模板和结构导向功能构建三维多级微纳结构，研究材料成核/生长过程，揭示离子液体中三维多级微纳结构形成机理，实现特殊形貌富锂锰基正极材料的可控制备。研究三维多级微纳结构中一级纳米单元、二级微米单元对锂离子传输特性及电子电导率的影响规律，揭示三维多级微纳结构在电化学过程中的储/脱/嵌锂机制，明晰材料微观结构与电化学性能之间的“构效关系”，为制备高性能富锂锰基正极材料提供理论和实验依据，为湘西、武陵山片区锰资源的高效合理利用提供新思路与新方法。

Using power lithium-ion batteries is the development directions for lithium-ion battery, which is concerned about the energy strategy in future. In order to improve the electronic conductivity and lithium ion diffusion of the lithium-rich manganese-based cathode material, we design a three-dimensional hierarchically nano/microstructure to improve electronic conductivity and lithium ion diffusion characteristic and hence to improve the rate capability via an ionic liquid-assisted synthetic method. Ionic liquid are selected to construct three-dimensional hierarchically nano/microstructure based on the function of template and structure oriented. The nucleation and growth processes of powders are researched and the growth mechanism of these three-dimensional hierarchically nano/microstructured materials are revealed. The influence of nano/microstructure on lithium ion transmission and electronic conductivity are investigated systematically, the mechanism of storage/insertion/deinsertion of lithium ion and the “structure-performance” relationship between the structure and electrochemical properties are revealed. All of these are expected to provide theoretical and experimental data for the preparation of high performance of lithium-rich manganese-based cathode material. It is also beneficial to the efficient utilization of manganese resources in Xiangxi and Wuling Mountain area.