功能离子液体基复合固态电解质的设计研制及新结构存储器件的构筑

The ionic liquids have low vapor pressure, wide liquid temperature range and good thermal stability and electrochemical performance. The application of ionic liquids as electrolyte in lithium secondary batteries has a positive effect on improving safety and extending the operating temperature range. Development of solid state lithium secondary batteries with functional ionic liquid-based composite solid state electrolytes is one of the effective ways to meet the demands of high energy density, high power characteristics and high safety of storage device. The project aims to develop novel ionic liquid-based composite solid state electrolytes with high safety and good electrochemical performances, which is focused on composite inorganic materials of functional ionic liquid with special structures. Novel multiple composite solid state electrolytes with nanosturctures are prepared through optimization of preparation methods and composition formulation. The interface characteristics of the composite solid state electrolytes are studied including the chemical and electrochemical stability, the capacity of charge exchange and ion transport, and physical configuration of interface films. To improve the compatibility between electrode and electrolyte, the interactions, micro structural changes and the electrochemical behavior of composite solid state electrolytes are analyzed using spectroscopy and quantum simulation. Through the optimization of solid state electrolytes materials and preparation processes, the novel structured storage devices with high safety and good electrochemical performances are trial-produced.

离子液体具有低的蒸汽压、宽的液相温度范围和良好的热学稳定性与电化学性能，应用于锂二次电池对于安全性的提高和工作温度范围的拓宽都具有积极作用，应用功能化的离子液体构建新型复合固体电解质材料发展固态锂二次电池是满足高能量密度、高功率特性的需求并改善安全性问题的有效途径之一。本课题以开发具有高安全性、优良电化学性能的离子液体基复合固态电解质为目标，重点采用具有特定结构特征的功能化离子液体复合无机材料，并通过合成方法、组成配比的优化，研制出新型纳米多元复合固态电解质材料；对其界面特性进行研究，分析复合固态电解质材料的化学与电化学稳定性、电荷交换与离子输运能力及其界面膜的物理构型；结合谱学和量化计算分析复合固态电解质材料组分间的相互作用、微结构变化和电化学行为特征，改善其与电极材料的相容性；进一步通过固态电解质材料优化、成型工艺的研究，试制出具有高安全性、优良电化学性能的新结构存储器件。

离子液体是由阴阳离子组合而成的液态盐，具有低的蒸汽压、宽的液相温度范围和良好的热学稳定性与电化学性能，用于替代目前广泛使用的碳酸酯溶剂电解质，对提高锂离子电池安全性和拓宽电池工作温度范围具有积极作用。本项目重点围绕新型功能离子液体基复合电解质材料开展了设计研究，合成高性能锂二次电池所适用的新型电解质，探究其内在作用机制并实现对界面、体相等技术难题的突破，实现新结构存储器件的构筑，为高性能二次电池及功能电解质材料的发展提供理论与技术支持。