WIDE TEMPERATURE ELECTROLYTE
An electrolyte includes a lithium salt dissolved in a solvent mixture. The solvent mixture may include a first solvent component including an organic solvent having no carbonate groups; a second solvent component configured to improve the electrochemical properties of the first solvent at low temperatures; a third solvent compound configured to promote formation of a passivating SEI layer between the electrolyte and an electrode layer; and a fourth solvent compound configured to stabilize a lithium salt at high temperatures.
1 . An electrolyte comprising:
a solvent mixture comprising:
at least one first solvent component comprising an organic solvent having no carbonate groups;
at least one second solvent component comprising a compound configured to improve the electrochemical properties of the first solvent at low temperatures;
at least one third solvent compound configured to promote formation of a passivating SEI between the electrolyte and an electrode layer; and
a lithium salt dissolved in the solvent mixture.
2 . The electrolyte of claim 1 , wherein the lithium salt comprises a lithium cation and an organic anion.
3 . The electrolyte of claim 2 , wherein the organic anion which comprises at least two halogen groups.
4 .- 7 . (canceled)
8 . The electrolyte of claim 3 , wherein the halogen groups are fluorine groups.
9 . The electrolyte of claim 2 , wherein the organic anion is a symmetric molecule centered about a nitrogen atom.
10 . The electrolyte of claim 9 , wherein the organic anion comprises two chains extending from this central atom each comprising a sulfur containing group.
11 . The electrolyte of claim 10 , wherein the sulfur containing group comprises a sulfonyl group.
12 . The electrolyte of claim 11 , wherein the sulfonyl group is a sulfonyl halide.
13 . The electrolyte of claim 2 , wherein the lithium salt comprises lithium bis(trifluoromethanesulfonyl)imide or lithium bis(fluorosulfonyl)imide.
14 . The electrolyte of claim 2 , wherein the lithium salt consists essentially of lithium bis(trifluoromethanesulfonyl)imide.
15 . The electrolyte of claim 1 , wherein the first solvent compound comprises at least one of butyronitrile, ethyl butyrate, methyl butyrate or butyl butyrate.
16 . The electrolyte of claim 1 , wherein the second solvent compound inhibits lithium dendrite formation at temperatures below −40 C.
17 . (canceled)
18 . (canceled)
19 . The electrolyte of claim 16 , wherein second solvent compound comprises at least one of gamma-butyrolactone, ethylene carbonate, diethyl carbonate, propylene carbonate, ethylmethyl carbonate or dimethyl carbonate.
20 . The electrolyte of claim 1 , wherein the third solvent compound is selected such that a substantial fraction of the compound is expended during a formation of the SEI.
21 . The electrolyte of claim 1 , wherein the third solvent compound comprises vinylene carbonate or fluoroethylene carbonate.
22 . The electrolyte of claim 1 , further comprising a fourth solvent compound, wherein the fourth solvent compound comprises an organosilicon compound.
23 . The electrolyte of claim 22 , wherein the fourth solvent compound comprises 4-[fluoro(dimethyl)silyl]butanenitrile.
24 . A lithium ion capacitor comprising the electrolyte of claim 1 .
25 . A lithium ion battery comprising the electrolyte of claim 1 .
26 . An electric double later capacitor comprising the electrolyte of claim 1 .
27 .- 32 . (canceled)