含LiDFOB的FEC/PC/DMC基电解液的高电压电化学性能  

High Voltage Electrochemical Properties of FEC/PC/DMC Electrolyte with LiDFOB

作　　者：张亮 张兰[2] 陈仕谋[2] 王轶博[3] 吕兴梅[2] Liang ZHANG;Lan ZHANG;Shimou CHEN;Yibo WANG;Xingmei LV(School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China;Beijing Key Laboratory of lonic Liquids Clean Process, Key Laboratory of Green Process and Engineering, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;School of Science, Beijing Technology and Business University, Beijing 100048, China)

机构地区：[1]中国科学院大学化学与化工学院,北京100049 [2]中国科学院过程工程研究所多相复杂系统国家重点实验室,绿色过程与工程重点实验室.离子液体清洁过程北京市重点实验室,北京100190 [3]北京工商大学理学院,北京100048

出　　处：《过程工程学报》2018年第3期605-611,共7页The Chinese Journal of Process Engineering

基　　金：国家自然科学基金资助项目(编号:21476234;21210006;21336002);河南省科技开放合作项目(编号:172102110019)

摘　　要：利用氟代碳酸乙烯酯（FEC）和二氟草酸硼酸锂（LiDFOB）优良的成膜性、稳定性和耐高压性,研究了在1 mol/L LiPF6FEC/碳酸丙烯酯（PC）/碳酸二甲酯（DMC）中加入LiDFOB和三（三甲基硅烷）硼酸酯（TMSB）对高电压材料LiNi（0.5）Mn（1.5）O4电化学性能的影响,利用循环伏安法和扫描电镜分析了两种电解液中电化学性能的差异.结果表明,在FEC基电解液中加入LiDFOB和添加剂TMSB使电解液的分解电位提高至5.5 V（vs.Li/Li^＋）以上,对铝箔有良好的钝化作用.Li/LiNi（0.5）Mn（1.5）O4半电池在含LiDFOB和TMSB的电解液中的初始放电比容量达126.8 mA·h/g,库伦效率为99%,充放电200次后比容量仍为108.2 mA·h/g,容量保持率为85.3%.而在不含LiDFOB和TMSB的电解液中,电池容量迅速衰减,85次充放电循环后容量保持率仅为60.7%.Fluoroethylene carbonate（FEC） and lithium oxalyldifluoroborate（LiDFOB） were regarded as the excellent solvent and additive for high voltage lithium-ion battery electrolyte due to their excellent electrochemical stability and protection film forming ability. LiDFOB and Tris（trimethylsilyl）borate（TMSB） were chosen as additive of 1 mol/L LiPF6FEC/Propylene carbonate（PC）/Dimethyl carbonate（DMC） electrolyte for LiNi（0.5）Mn（1.5）O4 battery. The electrochemical performances of the electrolytes LiDFOB and additive TMSB have been systematically investigated. The differences between these two electrolytes were also demonstrated by SEM and cyclic voltammetry. The results showed that decomposed potential of the electrolyte with LiDFOB＋additive TMSB can be enhanced to 5.5 V（vs. Li/Li^＋） and the Al current collector could be effectively passivated. The initial discharge capacity of Li/LiNi（0.5）Mn（1.5）O4 half cell operated with electrolyte with LiDFOB and TMSB was 126.8 mA·h/g, the coulomb efficiency was 99%. After 200 cycles, the discharge specific capacity was 108.2 mA·h/g, and it added retained 85.3% of its initial discharge capacity, while it is only 60.7% after 85 cycles for the one operated with the same basic electrolyte but without additive.

关 键 词：高电压电解液 二氟草酸硼酸锂 氟代碳酸乙烯酯 锂离子电池 LiNi(0.5)Mn(1.5)O4 

分 类 号：O646[理学—物理化学] O614.111[理学—化学]