Non-aqueous electrolytes for batteries
A non-aqueous electrolyte, with a coulombic efficiency with respect to lithium of at least 80%, that includes a Group 1 salt dissolved in a mixture containing two sulfone compounds, a mixture containing a sulfone compound and a sultone compound, and/or a mixture containing a sulfone compound and a sulfonamide compound. The Group 1 salt can be a lithium salt, the sulfone compound can be a cyclic sulfone such as thietane-1,1-dioxide and sulfolane, the sultone compound can be a cyclic sultone such as 1,3-propane sultone, and the sulfonamide compound can be a partially fluorinated sulfonamide such as 1,1,1-trifluoro-N,N-dimethylmethanesulfonamide and N-butyl-1,1,1-trifluoro-N-methylmethanesulfonamide. Additives such as another lithium salt, a polyunsaturated compound, a cyclic anhydride, a cyclic unsaturated sultone, and/or a cyclic phosphate can be included in the non-aqueous electrolyte.
1 . A non-aqueous electrolyte consisting essentially of:
(a) at least 97 weight percent (wt. %) of a mixture comprising:
a solvent; and
a Group 1 salt excluding lithium nitrate dissolved in the solvent;
the solvent consisting of: at least 50 wt. % of a sulfone compound and at least 20 wt. % of a saturated sultone compound;
the concentration of the Group 1 salt dissolved in the solvent being between 0.1 molal and 24 molal; and
(b) optionally, 3 wt. % or less of at least one additive selected from the group consisting of a lithium salt excluding lithium nitrate, a polyunsaturated compound, a cyclic anhydride, a cyclic unsaturated sultone, and a cyclic phosphate,
the non-aqueous electrolyte comprising a coulombic efficiency with respect to plating and stripping of lithium of at least 80%.
2 . The non-aqueous electrolyte according to claim 1 , wherein the Group 1 salt is at least one of lithium bis(trifluoromethanesulfonyl)imide, lithium bis (fluorosulfonyl)imide, lithium bis(oxalate)borate, lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium tetracyanoborate, lithium perchlorate, lithium tris(trifluoromethanesulfonyl)methanide, lithium tetrafluorooxalatophosphate, and any combination thereof.
3 . The non-aqueous electrolyte according to claim 1 , wherein the sulfone compound includes a cyclic sulfone, and the cyclic sulfone is selected from the group consisting of thietane-1,1-dioxide and sulfolane.
4 . The non-aqueous electrolyte according to claim 1 , wherein the non-aqueous electrolyte includes at least 0.05 weight percent (wt. %) of the at least one additive, the lithium salt is lithium bis(oxalate)borate, the polyunsaturated compound is selected from the group consisting of triallyl cyanurate and triallyl isocyanurate, the cyclic anhydride is 3-methyl-4-phenyl-oxazolidine-2,5-dione, the cyclic unsaturated sultone is 1-propene-1,3-sultone, and the cyclic phosphate is 2-(allyloxy)-1,3,2-dioxaphospholane 2-oxide.
5 . A non-aqueous electrolyte consisting essentially of:
(a) at least 97 weight percent (wt. %) of a mixture comprising:
a solvent; and
a lithium salt excluding lithium nitrate dissolved in the solvent;
the solvent consisting of:
at least 50 weight percent (wt. %) of thietane-1,1-dioxide or 1,3-oxathiolane-3,3-dioxide; and 1,3-propane sultone, sulfolane, or N-butyl-1,1,1,-trifluoro-N-methylmethanesulfonamide, and
the lithium salt concentration being between 0.1 molal and 24 molal; and
(b) optionally, 3 wt. % or less of at least one additive selected from the group consisting of another lithium salt excluding lithium nitrate, a polyunsaturated compound, a cyclic anhydride, a cyclic unsaturated sultone, and a cyclic phosphate,
the non-aqueous electrolyte comprising a coulombic efficiency with respect to plating and stripping of lithium of at least 80%.
6 . The non-aqueous electrolyte according to claim 5 , wherein the lithium salt is at least one of lithium bis(trifluoromethanesulfonyl)imide, lithium bis (fluorosulfonyl)imide, lithium bis(oxalate)borate, lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium tetracyanoborate, lithium perchlorate, lithium tris((trifluoromethanesulfonyl)methanide, lithium tetrafluorooxalatophosphate, and any combination thereof.
7 . The non-aqueous electrolyte according to claim 5 , wherein the non-aqueous electrolyte includes at least 0.05 weight percent (wt. %) of the at least one additive, the another lithium salt is lithium bis(oxalate)borate, the polyunsaturated compound is selected from the group consisting of triallyl cyanurate and triallyl isocyanurate, the cyclic anhydride is 3-methyl-4-phenyl-oxazolidine-2,5-dione, the cyclic unsaturated sultone is 1-propene-1,3-sultone, and the cyclic phosphate is 2-(allyloxy)-1,3,2-dioxaphospholane 2-oxide.
8 . The non-aqueous electrolyte according to claim 5 , wherein the solvent consist of at least 20 wt. % of sulfolane, N-butyl-1,1,1-trifluoro-N-methylmethane-sulfonamide, or 1,3-propane sultone.
9 . The non-aqueous electrolyte according to claim 7 , wherein the at least one additive is 3-methyl-4-phenyl-oxazolidine-2,5-dione, 1-propene-1,3-sultone, 2-(allyloxy)-1,3,2-dioxaphospholane 2-oxide, or any combination thereof.
10 . The non-aqueous electrolyte of claim 9 , further comprising a coulombic efficiency with respect to plating and stripping of lithium of at least 90%.
11 . The non-aqueous electrolyte according to claim 1 , wherein the solvent consists of at least 50 wt. % of the saturated sultone compound.
12 . The non-aqueous electrolyte according to claim 1 , wherein the sulfone compound is thietane-1,1-dioxide and/or the saturated sultone compound is 1,3-propane sultone.
13 . The non-aqueous electrolyte according to claim 4 , wherein the at least one additive is 3-methyl-4-phenyl-oxazolidine-2,5-dione, 1-propene-1,3-sultone, 2-(allyloxy)-1,3,2-dioxaphospholane 2-oxide, or any combination thereof.