Ionic liquids for rechargeable lithium batteries

Salminen, Justin ; Papaiconomou, Nicolas ; Kerr, John ; Prausnitz,John ; Newman, John

COLLABORATION - UCBerkeley

关键词: Calorimetry;    Electrodes;    37;    Electrolytes;    Lithium;   

DOI  :  10.2172/929086
RP-ID  :  LBNL--58901
RP-ID  :  DE-AC02-05CH11231
RP-ID  :  929086

美国|英语

来源: UNT Digital Library

【 摘 要 】

We have investigated possible anticipated advantages of ionic-liquid electrolytes for use in lithium-ion batteries. Thermal stabilities and phase behavior were studied by thermal gravimetric analysis and differential scanning calorimetry. The ionic liquids studied include various imidazoliumTFSI systems, pyrrolidiniumTFSI, BMIMPF{sub 6}, BMIMBF{sub 4}, and BMIMTf. Thermal stabilities were measured for neat ionic liquids and for BMIMBF{sub 4}-LiBF{sub 4}, BMIMTf-LiTf, BMIMTFSI-LiTFSI mixtures. Conductivities have been measured for various ionic-liquid lithium-salt systems. We show the development of interfacial impedance in a Li|BMIMBF{sub 4} + LiBF{sub 4}|Li cell and we report results from cycling experiments for a Li|BMIMBF{sub 4} + 1 mol/kg LIBF{sub 4}|C cell. The interfacial resistance increases with time and the ionic liquid reacts with the lithium electrode. As expected, imidazolium-based ionic liquids react with lithium electrodes. We seek new ionic liquids that have better chemical stabilities.