锂电池用三聚甲醛基高性能电解质的研究进展

Research progress of 1,3,5-trioxane-based high-performance electrolytes for lithium batteries

急剧增长的电动汽车市场需求极大刺激了锂电池的发展.作为锂电池的关键组成部件,电解质在锂电池的安全性、与正负极的匹配性(影响能量密度)、长使役寿命等方面扮演着极为重要的角色.因此,高性能电解质的开发迫在眉睫.三聚甲醛(TXE)是合成聚甲醛最易获得且最便宜的原料之一.我们调研发现,TXE不仅可以作为合成工程塑料的单体,还可以成为构建锂电池高性能电解质的重要构成要素.目前已报道的TXE基电解质不仅可以显著改善锂电池电解质与电极的界面相容性,还能极大提升锂电池的安全性能,已经成为构建高能量密度、高安全性能和长使役寿命的锂电池的一种颇有成效的方法.因此,本综述从准固态锂电池与液态锂电池两个角度出发,详细介绍了锂电池用TXE基高性能电解质的分类设计以及电极/电解质界面构建和表征等,并就TXE作为准固态电解质前驱体、共聚物电解质、防热冲击自阻断电解质以及液态电解液添加剂等方面的作用机理和应用等进行了详细阐述,并在文末对TXE基高性能电解质存在的挑战以及未来发展趋势进行了展望.

The development of rechargeable lithium batteries for high energy density, high safety and long service life is continuously driven by the growing demand for electric vehicles. As a crucial component of lithium batteries,electrolytes play an extremely important role in the safety property, energy density and even service life of lithium batteries. Hence, electrolytes of high performance are highly desirable. 1,3,5-trioxane(TXE) is one of the most accessible and cheapest materials for the synthesis of polyformaldehyde(POM). Besides, it is one of the most promising candidates for preparing high-performance electrolytes because it could not only improve the interface compatibility with electrodes but also enhance the safety performance of the lithium battery. Significant efforts have been devoted to developing the TXE-based electrolyte to build high-energy density and high-safety performance lithium batteries.Therefore, this review mainly summarizes the classification and development of TXE-based high-performance electrolytes for both quasi-solid-state and liquid-state lithium batteries. In addition, the detailed construction and characterization of the as-formed electrode/electrolyte interface are also illustrated. Moreover, the application of TXEbased electrolytes as quasi-solid electrolyte precursors, copolymer electrolytes, thermally induced automatic shutdown electrolytes and co-solvent in liquid electrolytes, respectively, are also presented and discussed in detail. In the end, the remaining challenges and future development trends of TXE-based high-performance electrolytes are prospected.