锂离子电池高电压和耐燃电解液研究进展

摘要

The electrolyte is an indispensable constituent in lithium ion batteries,and its role conducts electricity by means of the transportation of charge carries between the pair of electrodes.Its properties directly affect the energy density,cycle life and safety of the battery.However,there are two major challenges to using carbonate-based electrolytes in recent lithium ion batteries (LIBs) to further increase the energy density of the devices without compromising the safety.One is that carbonate-based electrolytes are not sufficiently stable at the positive electrode,and the other is their relatively high flammability.Therefore,developing high voltage and flame retardant electrolytes for LIBs is highly desired.Herein,we review the recent progress and challenges in new electrolytes,focusing on high-voltage electrolytes,flame retardant electrolytes and highly concentrated electrolytes.Among the reported electrolytes,highly concentrated electrolytes are worth a special attention,showing various unusual functionalities,for example,high oxidative stability,low volatility,high reductive stability,and non-corrosive to A1.These special properties are totally different from that of the conventional 1 moloL-1 LiPF6/EC-based electrolytes,which are result from solution structures.A discussion is also provided in this review on the prospects of further development of new electrolytes for LIBs.%电解液作为锂离子电池的重要组成部分,起着传输离子的作用,电解液的性质对电池的容量、循环性能及安全性能等影响巨大.近年来,随着高电压、高能量密度锂离子电池的开发应用,现有常规碳酸酯电解液存在正极稳定性差、闪点低、易燃烧等问题.因此,发展高电压耐燃电解液是应用高电压高容量正极材料、发展高电压高容量高安全性锂离f电池的迫切需要.主要综述了高电压电解液、耐燃性电解液及兼具抗氧化性和耐燃性的高浓度电解液的研究进展和现状.在此基础上,对锂离子电池新型电解液的发展方向进行了展望.