SOLID STATE ELECTROLYTE FOR ENERGY STORAGE DEVICES
Ways of making a solid-state electrolyte are provided. Various energy storage devices, such as solid-state lithium-ion batteries, can incorporate the solid-state electrolyte. The solid-state electrolyte can be manufactured by dissolving a fluoropolymer with a solvent and combining the dissolved fluoropolymer with an ionic liquid. A lithium salt can be added to the combined fluoropolymer and ionic liquid to form an electrolyte solution, which can be used to impregnate a porous membrane to provide the solid-state electrolyte.
1 . A method of making a solid-state electrolyte, comprising:
dissolving a fluoropolymer with a solvent;
combining the dissolved fluoropolymer with an ionic liquid;
adding a lithium salt to the combined fluoropolymer and ionic liquid to form an electrolyte solution; and
impregnating a porous membrane with the electrolyte solution to thereby form the solid-state electrolyte.
2 . The method of claim 1 , wherein the fluoropolymer includes polyvinylidene fluoride.
3 . The method of claim 1 , wherein the fluoropolymer includes a polyvinylidene fluoride copolymer.
4 . The method of claim 1 , wherein the fluoropolymer includes poly(vinylidene fluoride-co-hexafluoropropylene).
5 . The method of claim 1 , wherein the solvent includes a ketone.
6 . The method of claim 1 , wherein the solvent includes acetone.
7 . The method of claim 1 , wherein dissolving the fluoropolymer with the solvent includes dissolving poly(vinylidene fluoride-co-hexafluoropropylene) in acetone at 40-60 degrees Celsius.
8 . The method of claim 1 , wherein the ionic liquid includes an organic cation and an organic anion.
9 . The method of claim 1 , wherein the ionic liquid includes a member selected from a group consisting of: 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide; N-methyl-N-propylpiperidinium bis(trifluoromethylsulfonyl)imide; 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide; N-methyl-N-propylpiperidinium bis(fluorosulfonyl)imide; 1-ethyl-3-methylimidazolium hexafluorophosphate; N-methyl-N-propylpiperidinium hexafluorophosphate; and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (CAS No. 174899-83-3).
10 . The method of claim 1 , wherein the lithium salt includes a member selected from a group consisting of: LiPF 6 ; LiBF 4 ; LiBOB (lithium bisoxalato borate); LiTFSI (lithium bis(trifluorosulfonyl)imide); LiFSI (lithium fluorosulfonylimide); LiClO 4 ; LiAsF 6 ; LiSbF 6 ; LiSA; LiTf (lithium trifluoromethanesulfonate); LiCTFSI (lithium cyano(trifluoromethanesulfonyl)imide); LiTDI (lithium 4,5-dicyano-2-trifluoromethylimidazole); LiPDI (lithium 4,5-dicyano-2-(pentafluoroethyl) imidazolide); LiDCTA (lithium 4,5-dicyano-1,2,3-triazolate); and LiB(CN) 4 .
11 . The method of claim 1 , wherein the lithium salt includes LiFSI (lithium fluorosulfonylimide).
12 . The method of claim 1 , wherein the porous membrane includes a member selected from a group consisting of: a polysaccharide; a fluoropolymer; and a polyolefin.
13 . The method of claim 1 , wherein the porous membrane is formed by sintering.
14 . The method of claim 1 , wherein the porous membrane is formed by expansion.
15 . A solid-state electrolyte made according to the method of claim 1 .
16 . A solid-state lithium-ion battery comprising a solid-state electrolyte made according to the method of claim 1 .
17 . A method of making a solid-state electrolyte, comprising:
dissolving a fluoropolymer with a solvent;
combining the dissolved fluoropolymer with an ionic liquid;
adding a lithium salt to the combined fluoropolymer and ionic liquid to form an electrolyte solution; and
impregnating a porous membrane with the electrolyte solution to thereby form the solid-state electrolyte;
wherein:
the fluoropolymer includes a polyvinylidene fluoride copolymer;
the solvent includes a ketone;
the ionic liquid includes an organic cation and an organic anion; and
the porous membrane includes a member selected from a group consisting of: a polysaccharide; a fluoropolymer; and a polyolefin.
18 . A solid-state electrolyte made according to the method of claim 17 .
19 . A solid-state lithium-ion battery comprising a solid-state electrolyte made according to the method of claim 17 .
20 . A vehicle comprising a solid-state lithium-ion battery having a solid-state electrolyte made according to the method of claim 17 .