| abstract |
A lithium sulfur battery is described that includes at least one fluoro-substituted compound. Preferred fluoro-substituted compounds that are primarily solvents are fluoro-substituted carboxylic esters, fluoro-substituted carboxylic amides, fluoro-substituted fluorinated ethers, fluoro-substituted carbamates, fluoro-substituted cyclic carbonates, and fluoro-substituted acyclic carbonates fluoro-substituted ethers, perfluoroalkyls Particularly selected from the group consisting of phosphoranes, fluoro-substituted phosphites, fluoro-substituted phosphates, fluoro-substituted phosphonates and fluoro-substituted heterocycles. Monofluoroethylene carbonate, cis-difluoroethylene carbonate, trans-difluoroethylene carbonate, 4,4-difluoroethylene carbonate, trifluoroethylene carbonate, tetrafluoroethylene carbonate, 4-fluoro-4-methyl-1,3-dioxolane-2 -On, 4-fluoro-4-ethyl-1,3-dioxolan-2-one, 2,2,2-trifluoroethyl-methyl carbonate, 2,2,2-trifluoroethyl-fluoromethyl carbonate are preferred. The solvent may further comprise a non-fluorinated solvent such as ethylene carbonate, dialkyl carbonate or propylene carbonate. The present invention also relates to the use of fluorinated compounds and specific electrolyte solutions as additives for such batteries. |