Gel electrolytes based on ionic liquids for advanced lithium polymer batteries

A new ionic liquid-based polymer gel electrolyte for lithium ion batteries is prepared by combining N-methyl-N-propylpyrrolidinium bis(trifluoromethylsulfonyl)azanide, organic carbonates, lithium bis(trifluoromethylsulfonyl) azanide, and poly(vinylidene fluoride-co-hexafluoropropylene). The conductivities of the gel electrolytes at room temperature are about 1-2 mS/cm. It is shown that the polymer gel electrolytes work effectively with a graphite anode and a LiCo1/3Mn1/3Ni1/3O2 cathode. Further it is proven that the addition of vinylene carbonate and 4-vinylpyridine considerably improves the cell performance. (C) 2012 Elsevier Ltd. All rights reserved.