层状-尖晶石集成氧化物的制备、微结构与电化学性能研究

多元层状化合物的纳米集成结构是固体化学的核心之一，在改变载流子传输和迁移等方面有显著优势，成为获得高性能锂离子电池正极材料技术的关键。针对这些材料在循环过程中过渡金属离子迁移产生的结构不稳定和倍率差等问题，本项目将基于我们多年来对多元氧化物的结构-电荷输运性质本质认识，拟通过合成控制，制备系列层状Li(LixMn2xM1-3x)O2-尖晶石纳米集成结构; 利用纳米组分单元的相互影响和层结构中阳离子无序控制等策略调变组分Li2MnO3的活化; 控制过渡金属离子向Li-O层的迁移，提高LiMO2结构稳定性, 改善层状纳米集成结构的电子和离子传导动力学，揭示层状纳米集成材料的微结构-稳定性-电化学性能之间内在联系。从固体化学理论上提出，并从实验上建立获得高能量密度和优异倍率性能新方法，为层状氧化物纳米集成结构的开发及在储能领域的应用提供2-3种新材料，推动新型锂离子电池正极材料及相关技术的发展。

Multi-component layered nano-integrated oxides are the cores of solid state chemistry. Because of the merits of adjusting carrier transport and hopping, nano-integrated oxides are expected to play the key roles in obtaining the high-performance lithium-ion battery materials and the relevant technologies. Nevertheless, all these materials suffer from the poor structural stability and rate capability that occurred during the electrochemical cycles. Based on our deep comprehension of the nature about structures and transport properties of multi-component oxides, this project aims at preparing a series of layered nano-integrated structure Li(LixMn2xM1-3x)O2-spinel. One key component, Li2MnO3, of this integrated structure would be first activated by taking use of the interactions between each nanoscale structural units and inhibiting cationic disordering in the layered structures. Further, the diffusion of transition metal ions to Li-O layers would be controlled so as to improve the structural stability and further to enhance the transport kinetics of electrons and lithium ions. All these make it possible to uncover the intrinsic relationships between microstructures, structural stabilities, and electrochemical performance of the integrated structures. Eventually, new methods of obtaining the high-energy storage and optimized rate capability would be theoretically proposed and experimentally verified. The goals of this project would provide two or three new materials for exploring layered nano-integrated structures and their applications in energy storage, promoting the development of the new generation of high-performance lithium-ion batteries and the relevant technologies.