基于离子液体的锂空电池电解液设计、合成及性能研究

With the aim of solving the present problems of organic electrolyte in lithium-air battery including instability and volatility, this work plans to design and synthesize a series of functionalized ionic liquids (ILs) as high performance non-aqueous electrolytes for lithium-air battery. Through studying the effect of functionalized IL electrolytes on the air electrode reactions and battery performance, a new class of IL-derived high quality electrolytes will be developed. Four parts are included in this work as follows. 1) By rationally designing the organic cations, two kinds of new ILs, i.e., di-functionalized ILs containing ether group and methoxypolyethylene or crown ether functionalized ILs will be synthesized. 2) The correlations of IL structure with their properties and performance will be explored. 3) The effect of structure and composition of IL based electrolytes on the oxygen reduction and evolution reactions occurring on air electrode will be extensively studied. 4) The performance of assembled batteries with electrolytes based on selected ILs will be particularly investigated. This study intends to obtain 1-2 excellent IL electrolytes for lithium-air battery, which have the excellent integrated properties including low viscosity, high stability, and good electrochemical performance, etc. This work mainly focuses on the deep study of relationship between IL structure or composition and battery performance, which will substantially promoted the development of clean energy.

针对当前锂空气电池有机电解液存在的不稳定，易挥发等问题，本课题拟设计合成一系列新型的功能化离子液体，通过研究其物化性质对空气电极反应及电池性能的影响，以期获得性能优异的锂空气电池非水性电解液体系。具体内容包括：对有机阳离子进行设计，合成两类功能化离子液体即：含醚基的双基团功能化离子液体和聚乙二醇单甲醚或冠醚功能化离子液体；重点研究离子液体的结构与性质之间的内在关系和规律；考察离子液体电解液对空气电极上氧还原和氧析出反应性能的影响；筛选性质优良的离子液体作为电解液，测试其组装成电池后的性能。本研究拟获得1-2种用于锂空气电池体系的粘度低、稳定性好、电化学性能优良的离子液体电解液。该研究对探索电解液的结构与组成与锂空气电池性能之间的关系，推动清洁能源的发展具有重要的意义。

本项目针对“基于离子液体的锂空电池电解液设计、合成及性能研究”开展了研究工作，主要研究内容及主要成果如下：.（1）设计合成了一系列阳离子为基于醚基的双功能化季铵盐，阴离子为全氟磺酰亚胺，如双三氟甲基磺酰亚胺（TFSI）及双氟代磺酰亚胺（FSI），的离子液体，详细表征了其物理化学性质，并考察了其作为锂空气电池电解液的性能。.（2）采用离子液体作为前驱体或调节剂制备了三种过渡金属与碳材料的复合催化剂，表征了其性质，并研究了其作为锂空气电池或锌空气电池的阴极催化剂时对电池性能的影响。.（3）采用一步法合成了高纯度二烷基咪唑四氟硼酸离子液体，研究了其性质性能，并与传统的两步法离子液体的性质进行了系统的比较。并发展了一种咪唑类离子液体中1-甲基咪唑（1-MIm）含量的电化学检测方法，1-MIm的检测限为20-35ppm； .（4）合成了几类基于聚氨酯的锂单离子导电聚合物材料，对其结构组成进行了详细表征，并研究了其热性质，电化学性质。