锂离子电池高电压电解液的研究现状

目前提高锂离子电池能量密度的途径主要有提高锂离子电池的工作电压和应用高工作电压的正极材料,因此,锂离子电池高电压电解液的研究和开发势在必行。本文概述了锂离子电池电解液和高电压电解液的特点,介绍了前线轨道理论中的HOMO和LUMO对电解液设计的指导意义。尤其是结合日本知名企业和科研机构在高电压电解液方面的研究成果,阐述了两种实现电解质高电压化的途径,即提高溶剂本身的耐氧化性和使用添加剂,总结了氟代酯、氟化醚、硼酸酯、砜类和耐氧化添加剂等用于高电压电解液中的关键物质类型,并讨论了目前高电压电解液研究开发所带来的启示。

Research Progress of High-voltage Electrolytes for Lithium-ion Batteries

Increase of operating voltage of lithium-ion batteries and exploration of high-voltage cathode material become the main route to meet its requirement for high energy density, so it is necessary to research and design the high-voltage electrolyte systems matching with high energy lithium-ion batteries. The paper summarized the application of the lithium-ion battery electrolytes and characters of the high-voltage electrolytes, respectively. And the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) in the frontier orbital theory was also reviewed briefly, which are vital to the design of electrolytes. Especially combined with recent reports on high-voltage electrolytes of the Japanese leading enterprises and institutions, the paper introduced two approaches to achieve the high voltage electrolyte, including improving the oxidation resistance of the solvent and adding additives. Moreover, the key material types applied to high-voltage electrolytes were summarized, i.e. fluorinated esters, fluorinated ethers, boric acid esters, sulfones and anti-oxidation additives. Finally, some enlightenments about development of high-voltage electrolytes were discussed here.