高含量锂镧锆氧基复合固体电解质的制备及其性能研究

固态电解质具有优异的安全性能、工作温度范围宽、回收方便等优点，已成为新一代柔性电子器件中最具前景的电解质材料.为探索兼具高离子电导率和优良机械性能的固态电解质，将无机活性陶瓷锂镧锆氧（Lithium lanthanum zirconium oxide，LLZO）与改性聚离子液体复合，制备了一种性能优异的复合固态电解质.研究了LLZO与复合材料间结构的差异、LLZO的含量对复合固态电解质在离子电导率、机械性能的影响以及其抗压能力.结果表明，聚离子液体粘结剂的加入，赋予了固态电解质良好的柔顺性，并显著地提升了电解质的离子传输效率. 当复合固态电解质中LLZO为质量分数50%时，复合固态电解质的室温离子电导率达到最高值（1.45×10-4 S·cm-1），比单一的LLZO固态电解质的离子电导率高了一个数量级以上. 用维氏硬度来表征复合固态电解质的抗压能力，发现当LLZO为质量分数50%时，复合固态电解质的硬度可以达到0.45 gf/μm2.

Preparationand properties of high content of lithium lanthanum zirconium oxide based composite solid electrolyte

Solid electrolytes have been regarded as the most promising electrolyte materials for the next generation of flexible electronic devices due to their excellent safety, wide operating temperature range, recycling convenient and etc. In order to explore a solid electrolyte with high ionic conductivity and excellent mechanical properties, Lithium lanthanum zirconium oxide (LLZO) as an inorganic active ceramics was compounded with modified poly (ionic liquid) to prepare a composite solid electrolyte with excellent performance. The structural differences between LLZO and the composite materials, the influence of LLZO's content on ionic conductivity, mechanical properties and compressive resistance of the composite solid electrolyte were investigated. The results revealed that: adding poly (ionic liquid) based binder not only endowed good flexibility for solid electrolytes, but also significantly improved the ion conductive efficiency of the electrolytes. When the content of LLTO in the composite solid electrolyte is 50%, the electrolyte obtained the highest ionic conductivity (1.45×10-4 S·cm-1) which is one order of magnitude higher than that of the pristine LLZO. If the compression resistance of composite solid electrolyte was characterized by the Vickell hardness, the hardness of the composite solid state electrolyte can reach 0.45 gf/μm2 at a LLZO content of 50%.