CPC H01M 10/0569 (2013.01) [H01M 10/0525 (2013.01); H01M 10/0567 (2013.01); H01M 10/0568 (2013.01); H01M 2300/0034 (2013.01)] | 14 Claims |
1. An electrolyte composition comprising:
from 50 to about 80% by weight of a fluorinated solvent,
lithium bis (fluorosulfonyl) imide (LiFSI), in an amount of from 0.3% to about 5.0% by weight, based on the total weight of the electrolyte composition;
at least one linear or cyclic organic carbonate, that is fluorinated or non-fluorinated in an amount of from about 20% to about 40% by weight of the electrolyte composition; and
a main electrolyte different from LiFSI and in a greater amount than LiFSI, at a concentration ranging from 0.5 to 1.2M, and selected from the group consisting of lithium hexafluorophosphate (LiPF6), lithium bis (trifluoromethanesulfonyl) imide, lithium bis (perfluoroethanesulfonyl) imide, lithium (fluorosulfonyl) (nonafluorobutanesulfonyl) imide, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium trifluoromethanesulfonate, lithium tris (trifluoromethanesulfonyl) methide, Li2B12F12-xHx where x is equal to 0 to 8, mixtures of lithium fluoride and anion receptor B (OC6F5)3 and mixtures thereof,
wherein the fluorinated solvent is an acyclic carboxylic acid esters represented by the formula:
R1—COO—R2
wherein
i) R1 is an alkyl group;
ii) R2 is a fluoroalkyl group; and
iii) R1 and R2, taken as a pair, comprise at least two carbon atoms but not more than seven carbon atoms.
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