CN117477040A - Electrolyte and lithium ion battery containing same - Google Patents
Electrolyte and lithium ion battery containing same Download PDFInfo
- Publication number
- CN117477040A CN117477040A CN202311818961.9A CN202311818961A CN117477040A CN 117477040 A CN117477040 A CN 117477040A CN 202311818961 A CN202311818961 A CN 202311818961A CN 117477040 A CN117477040 A CN 117477040A
- Authority
- CN
- China
- Prior art keywords
- lithium
- electrolyte
- ion battery
- lithium ion
- carbonate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000003792 electrolyte Substances 0.000 title claims abstract description 91
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 title claims description 52
- 229910001416 lithium ion Inorganic materials 0.000 title claims description 52
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims abstract description 79
- 229910052744 lithium Inorganic materials 0.000 claims abstract description 71
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims abstract description 67
- 239000002608 ionic liquid Substances 0.000 claims abstract description 45
- 239000002904 solvent Substances 0.000 claims abstract description 44
- JBTWLSYIZRCDFO-UHFFFAOYSA-N ethyl methyl carbonate Chemical compound CCOC(=O)OC JBTWLSYIZRCDFO-UHFFFAOYSA-N 0.000 claims abstract description 33
- 229910003002 lithium salt Inorganic materials 0.000 claims abstract description 24
- 159000000002 lithium salts Chemical class 0.000 claims abstract description 24
- 239000000654 additive Substances 0.000 claims abstract description 23
- 230000000996 additive effect Effects 0.000 claims abstract description 21
- 238000002360 preparation method Methods 0.000 claims description 50
- LCGLNKUTAGEVQW-UHFFFAOYSA-N Dimethyl ether Chemical compound COC LCGLNKUTAGEVQW-UHFFFAOYSA-N 0.000 claims description 38
- SBLRHMKNNHXPHG-UHFFFAOYSA-N 4-fluoro-1,3-dioxolan-2-one Chemical compound FC1COC(=O)O1 SBLRHMKNNHXPHG-UHFFFAOYSA-N 0.000 claims description 21
- RXKLBLXXQQRGJH-UHFFFAOYSA-N bis(fluorosulfonyl)azanide 1-methyl-1-propylpyrrolidin-1-ium Chemical compound CCC[N+]1(C)CCCC1.FS(=O)(=O)[N-]S(F)(=O)=O RXKLBLXXQQRGJH-UHFFFAOYSA-N 0.000 claims description 15
- 229910013553 LiNO Inorganic materials 0.000 claims description 13
- -1 lithium hexafluorophosphate Chemical group 0.000 claims description 13
- XTHFKEDIFFGKHM-UHFFFAOYSA-N Dimethoxyethane Chemical compound COCCOC XTHFKEDIFFGKHM-UHFFFAOYSA-N 0.000 claims description 12
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 claims description 12
- IIPYXGDZVMZOAP-UHFFFAOYSA-N lithium nitrate Chemical compound [Li+].[O-][N+]([O-])=O IIPYXGDZVMZOAP-UHFFFAOYSA-N 0.000 claims description 12
- QSZMZKBZAYQGRS-UHFFFAOYSA-N lithium;bis(trifluoromethylsulfonyl)azanide Chemical compound [Li+].FC(F)(F)S(=O)(=O)[N-]S(=O)(=O)C(F)(F)F QSZMZKBZAYQGRS-UHFFFAOYSA-N 0.000 claims description 12
- 229910003473 lithium bis(trifluoromethanesulfonyl)imide Inorganic materials 0.000 claims description 11
- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 claims description 9
- 239000007774 positive electrode material Substances 0.000 claims description 9
- VAYTZRYEBVHVLE-UHFFFAOYSA-N 1,3-dioxol-2-one Chemical compound O=C1OC=CO1 VAYTZRYEBVHVLE-UHFFFAOYSA-N 0.000 claims description 6
- JWUJQDFVADABEY-UHFFFAOYSA-N 2-methyltetrahydrofuran Chemical compound CC1CCCO1 JWUJQDFVADABEY-UHFFFAOYSA-N 0.000 claims description 6
- XKTYXVDYIKIYJP-UHFFFAOYSA-N 3h-dioxole Chemical compound C1OOC=C1 XKTYXVDYIKIYJP-UHFFFAOYSA-N 0.000 claims description 6
- BTBUEUYNUDRHOZ-UHFFFAOYSA-N Borate Chemical compound [O-]B([O-])[O-] BTBUEUYNUDRHOZ-UHFFFAOYSA-N 0.000 claims description 6
- OIFBSDVPJOWBCH-UHFFFAOYSA-N Diethyl carbonate Chemical compound CCOC(=O)OCC OIFBSDVPJOWBCH-UHFFFAOYSA-N 0.000 claims description 6
- DHXVGJBLRPWPCS-UHFFFAOYSA-N Tetrahydropyran Chemical compound C1CCOCC1 DHXVGJBLRPWPCS-UHFFFAOYSA-N 0.000 claims description 6
- KFDQGLPGKXUTMZ-UHFFFAOYSA-N [Mn].[Co].[Ni] Chemical compound [Mn].[Co].[Ni] KFDQGLPGKXUTMZ-UHFFFAOYSA-N 0.000 claims description 6
- YKYONYBAUNKHLG-UHFFFAOYSA-N n-Propyl acetate Natural products CCCOC(C)=O YKYONYBAUNKHLG-UHFFFAOYSA-N 0.000 claims description 6
- 239000007773 negative electrode material Substances 0.000 claims description 6
- 229940090181 propyl acetate Drugs 0.000 claims description 6
- RUOJZAUFBMNUDX-UHFFFAOYSA-N propylene carbonate Chemical compound CC1COC(=O)O1 RUOJZAUFBMNUDX-UHFFFAOYSA-N 0.000 claims description 6
- ZUHZGEOKBKGPSW-UHFFFAOYSA-N tetraglyme Chemical compound COCCOCCOCCOCCOC ZUHZGEOKBKGPSW-UHFFFAOYSA-N 0.000 claims description 6
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 claims description 6
- NQPDZGIKBAWPEJ-UHFFFAOYSA-N valeric acid Chemical compound CCCCC(O)=O NQPDZGIKBAWPEJ-UHFFFAOYSA-N 0.000 claims description 6
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 claims description 5
- ODRHHBJRWDEQCY-UHFFFAOYSA-N 1-butyl-1-propylimidazol-1-ium Chemical compound CCCC[N+]1(CCC)C=CN=C1 ODRHHBJRWDEQCY-UHFFFAOYSA-N 0.000 claims description 4
- 229910015872 LiNi0.8Co0.1Mn0.1O2 Inorganic materials 0.000 claims description 4
- IEJIGPNLZYLLBP-UHFFFAOYSA-N dimethyl carbonate Chemical compound COC(=O)OC IEJIGPNLZYLLBP-UHFFFAOYSA-N 0.000 claims description 4
- VDVLPSWVDYJFRW-UHFFFAOYSA-N lithium;bis(fluorosulfonyl)azanide Chemical compound [Li+].FS(=O)(=O)[N-]S(F)(=O)=O VDVLPSWVDYJFRW-UHFFFAOYSA-N 0.000 claims description 4
- KTQDYGVEEFGIIL-UHFFFAOYSA-N n-fluorosulfonylsulfamoyl fluoride Chemical compound FS(=O)(=O)NS(F)(=O)=O KTQDYGVEEFGIIL-UHFFFAOYSA-N 0.000 claims description 4
- LZDKZFUFMNSQCJ-UHFFFAOYSA-N 1,2-diethoxyethane Chemical compound CCOCCOCC LZDKZFUFMNSQCJ-UHFFFAOYSA-N 0.000 claims description 3
- VDFVNEFVBPFDSB-UHFFFAOYSA-N 1,3-dioxane Chemical compound C1COCOC1 VDFVNEFVBPFDSB-UHFFFAOYSA-N 0.000 claims description 3
- WNXJIVFYUVYPPR-UHFFFAOYSA-N 1,3-dioxolane Chemical compound C1COCO1 WNXJIVFYUVYPPR-UHFFFAOYSA-N 0.000 claims description 3
- RYHBNJHYFVUHQT-UHFFFAOYSA-N 1,4-Dioxane Chemical compound C1COCCO1 RYHBNJHYFVUHQT-UHFFFAOYSA-N 0.000 claims description 3
- CNJRPYFBORAQAU-UHFFFAOYSA-N 1-ethoxy-2-(2-methoxyethoxy)ethane Chemical compound CCOCCOCCOC CNJRPYFBORAQAU-UHFFFAOYSA-N 0.000 claims description 3
- NGUUMHKSNSFLOS-UHFFFAOYSA-N 2-methoxyethyl hydrogen carbonate Chemical compound COCCOC(O)=O NGUUMHKSNSFLOS-UHFFFAOYSA-N 0.000 claims description 3
- IRTCJFCIQKNFPP-UHFFFAOYSA-N 2-methyl-1,4-dioxane Chemical compound CC1COCCO1 IRTCJFCIQKNFPP-UHFFFAOYSA-N 0.000 claims description 3
- DSMUTQTWFHVVGQ-UHFFFAOYSA-N 4,5-difluoro-1,3-dioxolan-2-one Chemical compound FC1OC(=O)OC1F DSMUTQTWFHVVGQ-UHFFFAOYSA-N 0.000 claims description 3
- 229910013075 LiBF Inorganic materials 0.000 claims description 3
- HFCVPDYCRZVZDF-UHFFFAOYSA-N [Li+].[Co+2].[Ni+2].[O-][Mn]([O-])(=O)=O Chemical compound [Li+].[Co+2].[Ni+2].[O-][Mn]([O-])(=O)=O HFCVPDYCRZVZDF-UHFFFAOYSA-N 0.000 claims description 3
- 239000002253 acid Substances 0.000 claims description 3
- ZDMWZUAOSLBMEY-UHFFFAOYSA-N bis(trifluoromethylsulfonyl)azanide;1-butyl-1-methylpiperidin-1-ium Chemical class CCCC[N+]1(C)CCCCC1.FC(F)(F)S(=O)(=O)[N-]S(=O)(=O)C(F)(F)F ZDMWZUAOSLBMEY-UHFFFAOYSA-N 0.000 claims description 3
- SBZXBUIDTXKZTM-UHFFFAOYSA-N diglyme Chemical compound COCCOCCOC SBZXBUIDTXKZTM-UHFFFAOYSA-N 0.000 claims description 3
- QHGJSLXSVXVKHZ-UHFFFAOYSA-N dilithium;dioxido(dioxo)manganese Chemical compound [Li+].[Li+].[O-][Mn]([O-])(=O)=O QHGJSLXSVXVKHZ-UHFFFAOYSA-N 0.000 claims description 3
- VEWLDLAARDMXSB-UHFFFAOYSA-N ethenyl sulfate;hydron Chemical compound OS(=O)(=O)OC=C VEWLDLAARDMXSB-UHFFFAOYSA-N 0.000 claims description 3
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 claims description 3
- 229910001386 lithium phosphate Inorganic materials 0.000 claims description 3
- 229910001496 lithium tetrafluoroborate Inorganic materials 0.000 claims description 3
- GBPVMEKUJUKTBA-UHFFFAOYSA-N methyl 2,2,2-trifluoroethyl carbonate Chemical compound COC(=O)OCC(F)(F)F GBPVMEKUJUKTBA-UHFFFAOYSA-N 0.000 claims description 3
- YFNKIDBQEZZDLK-UHFFFAOYSA-N triglyme Chemical compound COCCOCCOCCOC YFNKIDBQEZZDLK-UHFFFAOYSA-N 0.000 claims description 3
- RIUWBIIVUYSTCN-UHFFFAOYSA-N trilithium borate Chemical compound [Li+].[Li+].[Li+].[O-]B([O-])[O-] RIUWBIIVUYSTCN-UHFFFAOYSA-N 0.000 claims description 3
- TWQULNDIKKJZPH-UHFFFAOYSA-K trilithium;phosphate Chemical compound [Li+].[Li+].[Li+].[O-]P([O-])([O-])=O TWQULNDIKKJZPH-UHFFFAOYSA-K 0.000 claims description 3
- HCGFUIQPSOCUHI-UHFFFAOYSA-N 2-propan-2-yloxyethanol Chemical compound CC(C)OCCO HCGFUIQPSOCUHI-UHFFFAOYSA-N 0.000 claims description 2
- 229910013870 LiPF 6 Inorganic materials 0.000 claims description 2
- 150000002596 lactones Chemical class 0.000 claims description 2
- 239000000463 material Substances 0.000 claims description 2
- GEWWCWZGHNIUBW-UHFFFAOYSA-N 1-(4-nitrophenyl)propan-2-one Chemical compound CC(=O)CC1=CC=C([N+]([O-])=O)C=C1 GEWWCWZGHNIUBW-UHFFFAOYSA-N 0.000 claims 1
- 230000000052 comparative effect Effects 0.000 description 26
- 238000000034 method Methods 0.000 description 25
- 229910052751 metal Inorganic materials 0.000 description 9
- 239000002184 metal Substances 0.000 description 9
- 230000008569 process Effects 0.000 description 7
- 230000003647 oxidation Effects 0.000 description 6
- 238000007254 oxidation reaction Methods 0.000 description 6
- 150000001450 anions Chemical class 0.000 description 5
- RAXXELZNTBOGNW-UHFFFAOYSA-N imidazole Natural products C1=CNC=N1 RAXXELZNTBOGNW-UHFFFAOYSA-N 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 239000011267 electrode slurry Substances 0.000 description 4
- 239000008151 electrolyte solution Substances 0.000 description 4
- 239000011888 foil Substances 0.000 description 4
- 150000002500 ions Chemical class 0.000 description 4
- 230000014759 maintenance of location Effects 0.000 description 4
- 239000011230 binding agent Substances 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 239000006258 conductive agent Substances 0.000 description 3
- 229940021013 electrolyte solution Drugs 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 238000011056 performance test Methods 0.000 description 3
- 238000007614 solvation Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- YEJRWHAVMIAJKC-UHFFFAOYSA-N 4-Butyrolactone Chemical compound O=C1CCCO1 YEJRWHAVMIAJKC-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 229910010941 LiFSI Inorganic materials 0.000 description 2
- 229910013872 LiPF Inorganic materials 0.000 description 2
- 101150058243 Lipf gene Proteins 0.000 description 2
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 2
- 239000002033 PVDF binder Substances 0.000 description 2
- KAESVJOAVNADME-UHFFFAOYSA-N Pyrrole Chemical compound C=1C=CNC=1 KAESVJOAVNADME-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 239000010405 anode material Substances 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 125000002091 cationic group Chemical group 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000012046 mixed solvent Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000005096 rolling process Methods 0.000 description 2
- 239000007784 solid electrolyte Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- CAQYAZNFWDDMIT-UHFFFAOYSA-N 1-ethoxy-2-methoxyethane Chemical compound CCOCCOC CAQYAZNFWDDMIT-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 230000003064 anti-oxidating effect Effects 0.000 description 1
- 239000003963 antioxidant agent Substances 0.000 description 1
- 230000003078 antioxidant effect Effects 0.000 description 1
- 239000012300 argon atmosphere Substances 0.000 description 1
- 239000012298 atmosphere Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000010406 cathode material Substances 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000009694 cold isostatic pressing Methods 0.000 description 1
- 238000010277 constant-current charging Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000001351 cycling effect Effects 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- HNCXPJFPCAYUGJ-UHFFFAOYSA-N dilithium bis(trifluoromethylsulfonyl)azanide Chemical compound [Li+].[Li+].FC(F)(F)S(=O)(=O)[N-]S(=O)(=O)C(F)(F)F.FC(F)(F)S(=O)(=O)[N-]S(=O)(=O)C(F)(F)F HNCXPJFPCAYUGJ-UHFFFAOYSA-N 0.000 description 1
- 125000000118 dimethyl group Chemical group [H]C([H])([H])* 0.000 description 1
- SNQXJPARXFUULZ-UHFFFAOYSA-N dioxolane Chemical compound C1COOC1 SNQXJPARXFUULZ-UHFFFAOYSA-N 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000007770 graphite material Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 208000037584 hereditary sensory and autonomic neuropathy Diseases 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000001764 infiltration Methods 0.000 description 1
- 230000008595 infiltration Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 238000004502 linear sweep voltammetry Methods 0.000 description 1
- TYZROVQLWOKYKF-ZDUSSCGKSA-N linezolid Chemical compound O=C1O[C@@H](CNC(=O)C)CN1C(C=C1F)=CC=C1N1CCOCC1 TYZROVQLWOKYKF-ZDUSSCGKSA-N 0.000 description 1
- 229960003907 linezolid Drugs 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 150000005677 organic carbonates Chemical class 0.000 description 1
- 150000002892 organic cations Chemical class 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 125000003386 piperidinyl group Chemical group 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- JUJWROOIHBZHMG-UHFFFAOYSA-N pyridine Substances C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 description 1
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 description 1
- 125000000168 pyrrolyl group Chemical group 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000007790 scraping Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- NQRYJNQNLNOLGT-UHFFFAOYSA-N tetrahydropyridine hydrochloride Natural products C1CCNCC1 NQRYJNQNLNOLGT-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
- H01M10/0566—Liquid materials
- H01M10/0569—Liquid materials characterised by the solvents
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
- H01M10/0566—Liquid materials
- H01M10/0567—Liquid materials characterised by the additives
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
- H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
- H01M10/0566—Liquid materials
- H01M10/0568—Liquid materials characterised by the solutes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Inorganic Chemistry (AREA)
- Materials Engineering (AREA)
- Secondary Cells (AREA)
Abstract
The invention relates to an electrolyte, comprising: 20-80 wt% of an ether solvent, 5-20 wt% of lithium salt, 5-70 wt% of an ionic liquid, 5-30 wt% of an ester solvent and 0-8 wt% of an additive. The electrolyte system has good compatibility with the metallic lithium negative electrode, and the voltage window is higher.
Description
Technical Field
The present invention relates to an electrolyte suitable for a lithium ion battery, and a lithium ion battery including the same.
Background
With the development of modern society, the use frequency of secondary batteries such as lithium ion batteries is increasing. The theoretical capacity of the metal lithium is about ten times that of the traditional graphite material, so that the advantage of directly using the metal lithium as the negative electrode in the aspect of improving the energy density is obvious. If a metallic lithium negative electrode is used in combination with a high voltage positive electrode, it is desirable to produce a battery having an energy density greater than 400 wh/kg.
However, most of the current commercial electrolytes mainly use organic carbonate solvents, and the stability of the commercial electrolytes to a metal lithium negative electrode is poor, so that the metal lithium negative electrode is extremely easy to react with the electrolyte, a great amount of active lithium is lost, and the solvents in the electrolyte are continuously consumed, so that the attenuation of the cell circulation capacity retention rate is accelerated. For the reasons, the metallic lithium anode material cannot be widely applied and popularized. Therefore, it is particularly important to develop an electrolytic solution system having good compatibility with a metallic lithium negative electrode material.
In addition, the research shows that the existing electrolyte mainly containing the ether solvent has better compatibility with the metallic lithium negative electrode, but has narrower electrochemical window and low oxidation resistance potential, can only be used in a low-voltage system with the upper limit voltage lower than 4.0V, and cannot be matched with a high-voltage positive electrode material. This limits to some extent the increase in the overall energy density of the cell.
Disclosure of Invention
The invention aims to construct an electrolyte system with good compatibility with a metallic lithium anode and a higher voltage window (4.2V). On the basis, the invention provides an electrolyte suitable for a lithium ion battery and the lithium ion battery using the electrolyte.
A first aspect of the present invention provides an electrolyte comprising:
20 to 80wt% of an ether solvent,
5 to 20wt% of a lithium salt,
5 to 70 weight percent of ionic liquid,
5-30wt% of an ester solvent
0-8 wt% of an additive.
In some embodiments, the ether solvent is present in an amount of 40 to 60wt%. In some embodiments, the lithium salt is present in an amount of 10 to 18wt%. In some embodiments, the ionic liquid is 5-40 wt%. In some embodiments, the ester solvent is present in an amount of 10 to 25wt%. In some embodiments, the content of the additive is 1-5wt%.
In some embodiments, the ether solvent is one or more selected from the group consisting of ethylene glycol dimethyl ether (DME), ethylene glycol methyl ethyl ether (EME), diethylene glycol dimethyl ether (G2), triethylene glycol dimethyl ether (G3), tetraethylene glycol dimethyl ether (G4), ethylene glycol diethyl ether (DEE), diethylene glycol methyl ethyl ether (dge), 1, 3-Dioxolane (DOL), 1, 3-dioxane (1, 3-DX), 1, 4-dioxane (1, 4-DX), 2-methyl-1, 4-dioxane (2-Me-1, 4-DX), tetrahydrofuran (THF), 2-methyltetrahydrofuran (2-Me-THF), and Tetrahydropyran (THP).
In some embodiments, the lithium salt is selected from lithium hexafluorophosphate (LiPF) 6 ) Lithium tetrafluoroborate (LiBF) 4 ) One or more of lithium bis (trifluoromethanesulfonyl) imide (LiTFSI), lithium bis (fluorosulfonyl) imide (LiLiFSI), lithium difluorooxalato borate (LiDFOB), and lithium dioxaoxalato borate (LiBOB).
In some embodiments, the ionic liquid is one or more selected from the group consisting of 1-butyl-1-propylimidazolium bis (fluorosulfonyl) imide, 1-butyl-1-methylpiperidinium bis (trifluoromethanesulfonyl) imide salt, and 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide.
In some embodiments, the ester solvent is one or more selected from the group consisting of gamma-butyrolactone (GBL), ethylene Carbonate (EC), propylene Carbonate (PC), diethyl carbonate (DEC), propyl Acetate (PA), dimethyl carbonate (DMC), ethylmethyl carbonate (EMC), fluoroethylene carbonate (FEC), (2-methoxyethyl) carbonate (BMEC), bis-fluoroethylene carbonate (DFEC), fluorinated bis (2, 2-trifluoroethyl) carbonate (TFEC), and 2, 2-trifluoroethylmethyl carbonate (FEMC).
In some embodiments, the additive is selected from the group consisting of Vinylene Carbonate (VC), vinyl sulfate (DTD), 1, 3-Propenolactone (PST), lithium nitrate (LiNO) 3 ) Lithium phosphate (Li) 3 PO 4 ) And lithium borate (Li) 3 BO 3 ) One or more of the following.
In some embodiments, the ether solvent is ethylene glycol dimethyl ether. In some embodiments, the lithium salt is lithium bis (trifluoromethanesulfonyl) imide. In some embodiments, the ionic liquid is 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide. In some embodiments, the ester solvent is FEC. In some embodiments, the additive is LiNO 3 。
The second aspect of the invention provides the use of the electrolyte of the first aspect of the invention as described above in a lithium ion battery.
A third aspect of the present invention provides a lithium ion battery comprising the electrolyte of the first aspect of the present invention described above.
In some embodiments, the lithium ion batteries of the present invention include metallic lithium as the negative electrode material.
In some embodiments, the positive active material of the lithium ion battery of the present invention is one or more of nickel cobalt manganese, lithium iron phosphate, lithium cobaltate, lithium manganate, lithium nickelate and lithium nickel cobalt manganate, preferably a nickel cobalt manganese ternary positive electrode material, more preferably LiNi 0.8 Co 0.1 Mn 0.1 O 2 。
The electrolyte system has good compatibility with a metallic lithium anode, and a voltage window (antioxidant potential) is higher (> 4.2V). Therefore, the lithium ion battery comprising the electrolyte provided by the invention can still have higher capacity retention rate after repeated charge and discharge under higher voltage. Further, according to some preferred embodiments of the present invention, by selecting preferred electrolyte components and preferred contents of each component, it is possible to further improve the compatibility of the electrolyte with the metallic lithium negative electrode while enabling to obtain a voltage window of up to 4.5V or more, thereby enabling the lithium ion battery including the electrolyte of the present invention to achieve a capacity retention rate of 80% or more after 100 cycles of charge and discharge at a charge voltage of 4.2V.
In addition, the invention also provides a lithium ion battery using the metal lithium as a negative electrode material and using the electrolyte, the lithium ion battery has low cost and simple structure, is suitable for large-scale production, and can obtain the technical effects.
Drawings
Fig. 1 shows a cycle capacity diagram of the high voltage lithium batteries of examples 1 to 8 of the present invention.
Fig. 2 shows the capacity ratio (constant current charge ratio) of the constant current charge capacity of 15 th turn in the cycle of the high voltage lithium battery of examples 1 to 8 of the present invention to the total charge process.
Detailed Description
The invention is further illustrated by the following detailed description. Unless otherwise defined, terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The numerical limits or ranges stated herein include the endpoints, and specifically include all values and subranges within the numerical limits or ranges.
Unless otherwise specified, the contents (%) in the present application are mass contents (wt%).
The first aspect of the present invention provides an electrolyte comprising:
20 to 80wt% of an ether solvent,
5 to 20wt% of a lithium salt,
5 to 70 weight percent of ionic liquid,
5-30wt% of an ester solvent
0-8 wt% of an additive.
In the present invention, the ether solvent may be one or more selected from the group consisting of ethylene glycol dimethyl ether (DME), ethylene glycol methylethyl ether (EME), diethylene glycol dimethyl ether (G2), triethylene glycol dimethyl ether (G3), tetraethylene glycol dimethyl ether (G4), ethylene glycol diethyl ether (DEE), diethylene glycol methylethyl ether (dge), 1, 3-Dioxolane (DOL), 1, 3-dioxane (1, 3-DX), 1, 4-dioxane (1, 4-DX), 2-methyl-1, 4-dioxane (2-Me-1, 4-DX), tetrahydrofuran (THF), 2-methyltetrahydrofuran (2-Me-THF), and Tetrahydropyran (THP). The ether solvent is preferably DME as a linear ether from the viewpoints of solvent properties, solubility to lithium salts, further improvement of ionic conductivity of the resulting electrolyte, compatibility with metallic lithium negative electrodes, and the like.
According to a preferred embodiment of the present invention, the content of the ether solvent is 40 to 60wt%, more preferably 45 to 55wt%. Specifically, the content of the ether solvent may be 20wt%, 25wt%, 30wt%, 35wt%, 40wt%, 45wt%, 50wt%, 55wt%, 60wt%, 65wt%, 70wt%, 75wt%, 80wt%, or the like.
In the present invention, the lithium salt may be selected from lithium hexafluorophosphate (LiPF) 6 ) Lithium tetrafluoroborate (LiBF) 4 ) Lithium bis (trifluoromethanesulfonyl imide) (LiTFSI), lithium bis (fluorosulfonyl imide) (LiFS)I) One or more of lithium difluorooxalato borate (LiDFOB), lithium dioxaato borate (LiBOB). In the lithium salts, the fluoride ions in the anions of LiFSI have stronger electron-withdrawing benefit, so that Li in the lithium salts + The lithium salt is preferably LiFSI because of higher dissociation and better solubility in various electrolyte solvents, resulting in higher ionic conductivity of the configured electrolyte.
According to a preferred embodiment of the present invention, the content of lithium salt is 10 to 18wt%, preferably 12 to 17wt%. Specifically, the content of the lithium salt may be 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, 18wt%, 19wt%, 20wt%, or the like.
In the present invention, the ionic liquid may be one or more selected from 1-butyl-1-propylimidazolium bis (fluorosulfonyl) imide, 1-butyl-1-methylpiperidinium bis (trifluoromethanesulfonyl) imide salt, 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide. Ionic liquids of the present invention include, but are not limited to, ionic liquid anion, cationic group-like substitutes. Examples of ionic liquid anions include, but are not limited to, cl - 、Br - 、I - 、BF 4 - 、PF 6 - 、N(CF 3 SO 2 ) 2 - And CF (compact F) 3 SO 3 - . Ionic liquid cations include, but are not limited to, organic cations containing nitrogen, sulfur, or phosphorus, such as alkylammonium cations, imidazole cations, pyridine cations, piperidine cations, and the like. Compared with the piperidinyl ionic liquid, the pyrrolyl ionic liquid has smaller cationic size, moderate viscosity and higher ionic conductivity; compared with imidazole ionic liquid, the pyrrole ionic liquid has higher stability to lithium metal. Thus, in some embodiments, the ionic liquid is preferably 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide.
According to a preferred embodiment of the present invention, the content of the ionic liquid is 5 to 40wt%, preferably 8 to 24wt%, more preferably 10 to 20wt%. Specifically, the content of the ionic liquid may be 5wt%, 10wt%, 15wt%, 20wt%, 25wt%, 30wt%, 35wt%, 40wt%, 45wt%, 50wt%, 55wt%, 60wt%, 65wt% or 70wt%, or the like.
In the present invention, the ester solvent may be one or more selected from the group consisting of gamma-butyrolactone (GBL), ethylene Carbonate (EC), propylene Carbonate (PC), diethyl carbonate (DEC), propyl Acetate (PA), dimethyl carbonate (DMC), ethylmethyl carbonate (EMC), fluoroethylene carbonate (FEC), (2-methoxyethyl) carbonate (BMEC), bis-fluoroethylene carbonate (DFEC), fluorinated bis (2, 2-trifluoroethyl) carbonate (TFEC), and 2, 2-trifluoroethyl methyl carbonate (FEMC). Considering that FEC can be used as a solvent and a film forming additive, and simultaneously participates in the construction of a lithium metal anode solid electrolyte interface (SEI, solid electrolyte interface) to react to generate LiF and LiCO 3 、LiRO x Thereby helping to further isolate the electrolyte from contact with the metal lithium, reducing side reaction of the electrolyte and the lithium negative electrode, reducing the consumption of the electrolyte and prolonging the cycle life. Therefore, the ester solvent is preferably FEC.
According to a preferred embodiment of the present invention, the content of the ester solvent is 10 to 25wt%, more preferably 12 to 20wt%. Specifically, the content of the ester solvent may be 3wt%, 5wt%, 10wt%, 15wt%, 20wt%, 25wt%, 30wt%, or the like.
In the present invention, the additive may be selected from Vinylene Carbonate (VC), vinyl sulfate (DTD), 1, 3-propenesulfonic acid lactone (PST), lithium nitrate (LiNO) 3 ) Lithium phosphate (Li) 3 PO 4 ) Lithium borate (Li) 3 BO 3 ) One or more of the following. When the lithium nitrate is used as an additive, lithium nitrate can provide lithium ions on one hand, nitrate has higher Donor Number (DN) and stronger interaction with the lithium ions on the other hand, and pushes away solvent molecules to reduce the solvent molecules and Li + Reducing the probability of solvent molecules to break down into films, increasing ion clusters within the primary solvation sheath, thereby forming anion-rich solvation sheaths, such as contact ion pairs (contact ion pairs, CIPs) and ion Aggregates (AGGs); at the same time NO 3 - Decomposing the lithium anode surface into film to obtain LiN x O y /LiN x /LiO x The SEI has higher ionic conductivity, and the SEI has higher interfacial energy and interfacial adhesion energy to Li metal, promotes uniform deposition of lithium, and is favorable for maintaining stable circulation of lithium metal cathode. Therefore, the additive is preferably LiNO 3 。
According to a preferred embodiment of the present invention, the content of the additive is 1 to 7wt%. Specifically, the content of the additive may be 0wt%, 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, or the like.
The second aspect of the invention provides the use of the electrolyte of the first aspect of the invention as described above in a lithium ion battery.
A third aspect of the present invention provides a lithium ion battery comprising the electrolyte of the first aspect of the present invention described above.
In some embodiments, the lithium ion battery of the present invention may be prepared by the steps of:
(1) Preparing a positive plate;
(2) Preparing an electrolyte; and
(3) And assembling the battery.
Step (1) and step (3) may be performed according to methods commonly used in the art for preparing a positive electrode sheet and assembling a battery. In some embodiments, in the step of preparing the positive electrode sheet, materials such as a positive electrode active material, a conductive agent, and a binder are mixed and dispersed in an organic solvent in a predetermined mass ratio to form a positive electrode slurry. The positive electrode slurry is then knife coated onto a metal foil, dried and further vacuum dried. And then rolling and slicing to prepare the positive plate. The positive electrode active material can be any one of nickel cobalt manganese, lithium iron phosphate, lithium cobaltate, lithium manganate, lithium nickelate and lithium nickel cobalt manganate, is preferably a nickel cobalt manganese ternary positive electrode material, and is more preferably LiNi 0.8 Co 0.1 Mn 0.1 O 2 . The conductive agent is preferably super P and the binder is preferably PVDF. The metal foil is preferably aluminum foil.
In step (2), the electrolyte may be obtained by mixing the various components of the electrolyte of the first aspect of the present invention in a predetermined ratio and then stirring until the lithium salt is completely dissolved.
In some embodiments, the positive and negative electrode cases, the elastic sheets and the gaskets of the button cell used for assembling the lithium battery are commercially available CR2032, and the metallic lithium sheet as the negative electrode material is a metallic lithium sheet having a thickness of 10 to 500 μm, preferably 10 to 50 μm from the viewpoints of cost and energy density.
Examples:
the present invention is described in detail below by way of examples, which are not intended to limit the present invention. The experimental methods in the following examples are conventional methods unless otherwise specified. The reagents and devices used in the following examples are all commercially available and are not particularly limited.
Example 1 preparation of lithium ion Battery Using the electrolyte of the invention
(1) Preparation of positive plate
Ternary cathode material (LiNi 0.8 Co 0.1 Mn 0.1 O 2 ) Mixing the conductive agent Super P and the binder PVDF according to the mass ratio of 8:1:1, dispersing in an organic solvent NMP (N-methyl pyrrolidone), stirring until the mixture is stable and uniform to form positive electrode slurry, scraping the positive electrode slurry on aluminum foil with the thickness of 10 mu m, drying at 80 ℃, heating to 120 ℃, further drying in vacuum, and rolling and slicing to prepare the positive electrode plate.
(2) Electrolyte preparation
51.5wt% of ether solvent DME, 15wt% of lithium salt LiTFSI, 16wt% of ionic liquid 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide, 16wt% of ester solvent FEC and 1.5wt% of additive LiNO 3 The mixture was stirred with a magnetic stirrer until the lithium salt was completely dissolved, to obtain an electrolyte.
(3) Lithium battery preparation
Sequentially assembling a negative electrode shell I, an elastic sheet I, a lithium sheet I, an electrolyte I, a diaphragm I, a positive electrode plate I and a positive electrode shell in a glove box under an inert atmosphere, and pressing for 5s at 800kPa to complete the assembly to prepare the button cell.
The basic compositions of the electrolytes used in examples 1 to 8 and comparative example 1 are shown in table 1.
Example 2 preparation of lithium ion Battery Using the electrolyte of the invention
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in example 2 was the same as in example 1.
As shown in Table 1, in the present example, unlike example 1, the proportion of ionic liquid 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide was adjusted down to 8% by weight, and the ether solvent was a mixed solvent of DME and DOL mixed at a ratio of 1:1 (volume ratio) and the proportion was increased to 59.5% by weight. The mass fraction of the rest components is unchanged.
Example 3 preparation of lithium ion Battery Using the electrolyte of the invention
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in example 3 was the same as in example 1.
As shown in table 1, unlike example 1, this example adjusts the ratio of the ester solvent FEC down to 8wt%, and the ether solvent uses a 1:1 (volume ratio) mixed solvent of DME and DOL and the ratio is increased to 59.5wt%. The mass fraction of the rest components is unchanged.
Example 4 preparation of lithium ion Battery Using the electrolyte of the invention
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in example 4 was the same as in example 1.
As shown in Table 1, unlike example 1, in this example, 1-butyl-1-propylimidazolium bis (fluorosulfonyl) imide was used as the ionic liquid and the proportion was increased to 24wt% and the proportion of the ether solvent DME was adjusted down to 43.5wt%. The mass fraction of the rest components is unchanged.
Example 5 preparation of lithium ion Battery Using the electrolyte of the invention
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in example 5 was the same as in example 1.
As shown in Table 1, in the present example, the ester solvent was mixed with the EC and FEC in a ratio of 1:1 (volume ratio) and the ratio was increased to 25wt%, and the ratio of the ether solvent DME was adjusted down to 42.5wt%, unlike example 1. The mass fraction of the rest components is unchanged.
Example 6 preparation of lithium ion Battery Using the electrolyte of the invention
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in example 6 was the same as in example 1.
As shown in Table 1, this example differs from example 1 in that the additive LiNO 3 The proportion of ether solvent DME was adjusted down to 50.5% by weight, with the proportion of (2) being increased to 2.5% by weight. The mass fraction of the rest components is unchanged.
Example 7 preparation of lithium ion Battery Using the electrolyte of the invention
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in example 7 was the same as in example 1.
As shown in Table 1, in the present example, unlike example 1, lithium bistrifluoromethanesulfonimide Lithium (LiTFSI) was used as the lithium salt in a constant ratio, and LiNO was used as the additive 3 The proportion of ether solvent DME was adjusted down to 49% by weight, with the proportion of (C) rising to 4.0% by weight. The mass fraction of the rest components is unchanged.
Example 8 preparation of lithium ion Battery Using the electrolyte of the invention
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in example 8 was the same as in example 1.
As shown in Table 1, this example was different from example 1 in that the proportion of ionic liquid 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide was adjusted down to 8% by weight and the proportion of ether solvent DME was adjusted down to 47% by weight. The mass fraction of the rest components is unchanged.
Example 9 preparation of lithium ion Battery Using the electrolyte of the invention
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in example 9 was the same as in example 1.
As shown in table 1, this example was different from example 1 in that the proportion of lithium salt LiTFSI was adjusted down to 5wt%, the proportion of ionic liquid 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide was adjusted up to 50wt%, the proportion of ester solvent FEC was adjusted up to 20wt%, and the proportion of ether solvent DME was adjusted down to 23.5wt%. The mass fraction of the rest components is unchanged.
Comparative example 1 preparation of lithium ion Battery Using Prior Art electrolyte
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in comparative example 1 was the same as in example 1.
As shown in table 1, comparative example 1 uses Ethylene Carbonate (EC): carbon (C)Dimethyl acid (DMC) =3:7, containing 1 mol/L LiPF 6 And 2wt% of FEC electrolyte to prepare a lithium battery.
Comparative example 2 preparation of lithium ion Battery Using Prior Art electrolyte
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in comparative example 2 was the same as in example 1.
As shown in Table 1, comparative examples 2, 3-Dioxolane (DOL) and 1, 2-Dimethoxyethane (DME) =3:7, containing 1 mol/L LiSSI and 2wt% LiNO 3 The electrolyte of (2) is used for preparing a lithium battery.
Comparative example 3 preparation of lithium ion Battery Using electrolyte having too low an ionic liquid proportion
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in comparative example 3 was the same as in example 1.
As shown in Table 1, this example was different from example 1 in that the proportion of ionic liquid 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide was adjusted down to 2% by weight and the proportion of ether solvent DME was adjusted up to 65.5% by weight. The mass fraction of the rest components is unchanged.
Comparative example 4 preparation of lithium ion Battery Using electrolyte having too low an ionic liquid proportion
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in comparative example 4 was the same as in example 1.
As shown in Table 1, unlike example 1, this example down-regulates the proportion of ionic liquid 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide to 2wt%, up-regulates the proportion of ether solvent DME to 67.0wt%, and no additive is used. The mass fraction of the rest components is unchanged.
Comparative example 5 preparation of lithium ion Battery Using electrolyte with too low an ionic liquid proportion
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in comparative example 5 was the same as in example 1.
As shown in table 1, this example was different from example 1 in that the proportion of lithium salt LiTFSI was adjusted up to 20wt%, the proportion of ionic liquid 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide was adjusted down to 2wt%, the proportion of ester solvent FEC was adjusted down to 8wt%, and the proportion of ether solvent DME was adjusted up to 68.5wt%. The mass fraction of the rest components is unchanged.
Comparative example 6 preparation of lithium ion Battery Using electrolyte having too low an ionic liquid proportion
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in comparative example 6 was the same as in example 1.
As shown in table 1, this example was different from example 1 in that the proportion of lithium salt LiTFSI was adjusted down to 12wt%, the proportion of ionic liquid 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide was adjusted down to 2wt%, the proportion of ester solvent FEC was adjusted up to 30wt%, and the proportion of ether solvent DME was adjusted up to 54.5wt%. The mass fraction of the rest components is unchanged.
Comparative example 7 preparation of lithium ion Battery Using electrolyte having too high an ester solvent ratio
The procedure for the preparation of the positive electrode sheet and the preparation of the lithium battery in comparative example 7 was the same as in example 1.
As shown in Table 1, this example was different from example 1 in that the proportion of ionic liquid 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide was adjusted down to 8wt%, the proportion of ester solvent FEC was adjusted up to 40wt%, and the proportion of ether solvent DME was adjusted down to 23.5wt%. The mass fraction of the rest components is unchanged.
TABLE 1
Performance test:
the performance test is carried out on the electrolyte solutions and the prepared lithium ion batteries in the examples 1-9 and the comparative examples 1-7 respectively, and the test process and method are as follows:
(1) Oxidation potential test
The high voltage resistance of the electrolyte was measured by linear sweep voltammetry. Under the argon atmosphere, the electrolyte to be tested, the stainless steel sheet and the lithium sheet form a button cell (wherein the stainless steel sheet is used as a working electrode, the lithium sheet is used as a reference electrode and a counter electrode), an electrochemical window of the button cell is tested on an electrochemical workstation (CHI 760D), the testing range is 2.5-5V, and the scanning speed is 1mV/s.
(2) Normal temperature cycle performance test
The lithium battery using the sample electrolyte was charged to 4.2V at a constant current and constant voltage of 0.33C at 25C, and then discharged to 3.0V at a constant current of 0.5C, thus 1 cycle. Coulombic efficiency is calculated as the ratio of the same cycle discharge capacity to the charge capacity.
Table 2 shows the oxidation resistance potential (in V) of the electrolytes of examples 1 to 9 and comparative examples 1 to 7. As shown in table 2, the electrolyte of the present invention exhibits excellent high voltage resistance and can be applied to a high voltage lithium battery. As shown in examples 4-9, when appropriate components and contents are selected, the antioxidation potential of the electrolyte may reach 4.4V or more.
In contrast, when the ionic liquid content is less than 8wt% (comparative examples 3-5), the voltage window is reduced to some extent (all lower than 4.2V). Therefore, the ether solvent in the electrolyte is easily oxidized and decomposed in a high voltage state when charged to 4.2V, and the overcharge phenomenon occurs in the battery.
In addition, in comparative examples 6 to 7, the content of the ester solvent was increased to allow the oxidation resistance potential to reach 4.20V or more. On the other hand, the assembled battery cells of comparative examples 6 to 7 are affected by Li due to too high ratio of ester electrolyte and too high solvent molecule ratio + Solvated structure, li + The surrounding anion content is reduced, the FEC coordination is increased, SEI which is mainly constructed by FEC solvent molecular decomposition is formed on the surface of the negative electrode, and under the solvation structure, the compatibility of electrolyte and a lithium negative electrode is poor. Meanwhile, as the FEC is decomposed into films to cause more gas production in the circulation process, the battery cell bulge can be observed in the circulation process, and the safety of the battery cell is easy to be reduced.
TABLE 2
Fig. 1 shows cycle capacity diagrams of high-voltage lithium batteries using examples 1 to 8 and comparative examples 1 to 2. As shown in fig. 1, the electrolyte solutions of examples 1 to 8 have high compatibility with the metallic lithium negative electrode material and high oxidation resistance potential, so that the lithium ion battery including the electrolyte solution of the present invention can still have a capacity retention rate of 70% or more after 60 charge and discharge cycles. In contrast, the lithium ion battery using the electrolyte of comparative example 1 began to significantly decrease in capacity after 20 cycles, while the capacity was decayed to below 70% after about 40 cycles. Analysis causes this phenomenon probably because the electrolyte is incompatible with the lithium metal anode material, and a stable SEI film cannot be formed. In the lithium ion battery using the electrolyte of comparative example 2, the electrochemical stability window is narrow, the ether solvent is easily oxidized and decomposed in the circulation process, the electrolyte consumes fast, and the capacity fade is accelerated.
On the other hand, as shown in fig. 1, by selecting appropriate electrolyte components and contents (examples 6 to 8), the capacity of a lithium ion battery using the electrolyte of the present invention after up to 100 charge and discharge cycles can be maintained at 80% or more.
Fig. 2 shows the 15 th constant current charge ratio during cycling using the high voltage lithium batteries of examples 1-8 and comparative example 1. By combining analysis of the table 2, the ionic liquid and the large-proportion ester solvent are mixed, so that the whole voltage window of the electrolyte is improved, and the voltage window is more than 4.2V.
On the other hand, when the content of the ionic liquid is increased within the content range of the invention, the practical application window of the electrolyte can be widened, and the stability and oxidation resistance of the electrolyte are improved. When the content of the ionic liquid is too low, the ionic conductivity of the ionic liquid is increased, the system impedance is reduced, the constant-current charge ratio is increased, but the system stability is weakened, and when the content of the ionic liquid is too high, the system impedance is obviously increased, and the constant-current charge ratio is reduced. When the content of the ionic liquid is outside the content range of the present invention, the effect is generally poor. When the content of the ionic liquid is too low, the ionic conductivity of the system is increased, the impedance is reduced, the constant-current charge ratio is increased, but the stability of the system is weakened; when the content of the ionic liquid is too high, the viscosity of the electrolyte is very high, the system impedance is obviously increased, the constant-current charging ratio is reduced, the electrolyte is very poor in infiltration of a cell diaphragm and a positive electrode gap, the processes of formation, capacity calibration and the like in the production of the cell cannot be completed, and the obtained electrolyte cannot meet the normal circulation of the cell.
On the other hand, the ester solvent and the ether solvent also reduce the electrolyte to a certain extentViscosity, improving ionic conductivity; secondly, an ester solvent participates in the film forming process of the cathode SEI to generate reduction products such as LiF, li (COOR) x and the like, and the main function of the ether solvent is to dissolve LiNO 3 The method comprises the steps of carrying out a first treatment on the surface of the Therefore, when the content of the ester solvent is too low, the film formation is insufficient, and the service life of the battery is affected; when the content of the ester solvent is too high, the ether solvent content is inevitably reduced, so that the solubility of the additive LiNO3 is reduced or even separated out; additives, especially LiNO 3 The reduction products are LiN, liNOx and the like with high conductivity and good stability, and have key effects on the generation of a negative electrode SEI film, the content of additives is reduced, the film formation is insufficient, and the service life of a battery is influenced; when LiNO 3 When the content of the electrolyte is too much, the viscosity of the electrolyte is obviously increased, the impedance of the system is increased, the constant current charge ratio of the battery core is reduced, and the circulation effect is gradually reduced.
Claims (14)
1. An electrolyte, characterized in that the electrolyte comprises:
20 to 80wt% of an ether solvent,
5 to 20wt% of a lithium salt,
5 to 70 weight percent of ionic liquid,
5-30wt% of an ester solvent
0-8 wt% of an additive.
2. Electrolyte according to claim 1, characterized in that the ether solvent content is 40-60 wt%, and/or the lithium salt content is 10-18 wt%, and/or the ionic liquid content is 5-40 wt%, and/or the ester solvent content is 10-25 wt%, and/or the additive content is 1-5 wt%.
3. The electrolyte according to claim 1, wherein the ether solvent is one or more selected from the group consisting of ethylene glycol dimethyl ether (DME), ethylene glycol methylethyl ether (EME), diethylene glycol dimethyl ether (G2), triethylene glycol dimethyl ether (G3), tetraethylene glycol dimethyl ether (G4), ethylene glycol diethyl ether (DEE), diethylene glycol methylethyl ether (dge), 1, 3-Dioxolane (DOL), 1, 3-dioxane (1, 3-DX), 1, 4-dioxane (1, 4-DX), 2-methyl-1, 4-dioxane (2-Me-1, 4-DX), tetrahydrofuran (THF), 2-methyltetrahydrofuran (2-Me-THF), and Tetrahydropyran (THP).
4. The electrolyte of claim 1, wherein the lithium salt is selected from lithium hexafluorophosphate (LiPF 6 ) Lithium tetrafluoroborate (LiBF) 4 ) One or more of lithium bis (trifluoromethanesulfonyl) imide (LiTFSI), lithium bis (fluorosulfonyl) imide (LiLiFSI), lithium difluorooxalato borate (LiDFOB), and lithium dioxaoxalato borate (LiBOB).
5. The electrolyte according to claim 1, wherein the ionic liquid is one or more selected from the group consisting of 1-butyl-1-propylimidazolium bis (fluorosulfonyl) imide, 1-butyl-1-methylpiperidinium bis (trifluoromethanesulfonyl) imide salt, and 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide.
6. The electrolyte according to claim 1, wherein the ester solvent is one or more selected from the group consisting of γ -butyrolactone (GBL), ethylene Carbonate (EC), propylene Carbonate (PC), diethyl carbonate (DEC), propyl Acetate (PA), dimethyl carbonate (DMC), methylethyl carbonate (EMC), fluoroethylene carbonate (FEC), (2-methoxyethyl) carbonate (BMEC), bis-fluoroethylene carbonate (DFEC), fluorinated bis (2, 2-trifluoroethyl) carbonate (TFEC) and 2, 2-trifluoroethylmethyl carbonate (FEMC).
7. The electrolyte according to claim 1, wherein the additive is selected from the group consisting of Vinylene Carbonate (VC), vinyl sulfate (DTD), 1, 3-propenesulfonic acid lactone (PST), lithium nitrate (LiNO) 3 ) Lithium phosphate (Li) 3 PO 4 ) And lithium borate (Li) 3 BO 3 ) One or more of the following.
8. The electrolyte according to any one of claim 1 to 7,characterized in that the ether solvent is ethylene glycol dimethyl ether, and/or the lithium salt is lithium bistrifluoromethanesulfonimide, and/or the ionic liquid is 1-methyl-1-propylpyrrolidinium bis (fluorosulfonyl) imide, and/or the ester solvent is FEC, and/or the additive is LiNO 3 。
9. Use of the electrolyte according to any one of claims 1 to 8 for the preparation of lithium ion batteries.
10. A lithium ion battery, characterized in that the lithium ion battery comprises the electrolyte as claimed in any one of claims 1 to 8.
11. The lithium ion battery of claim 10, wherein the lithium ion battery comprises metallic lithium as the negative electrode material.
12. The lithium ion battery of claim 10 or 11, wherein the positive active material of the lithium ion battery is one or more of nickel cobalt manganese, lithium iron phosphate, lithium cobaltate, lithium manganate, lithium nickelate, and lithium nickel cobalt manganate.
13. The lithium ion battery of claim 12, wherein the positive active material of the lithium ion battery is a nickel cobalt manganese ternary positive material.
14. The lithium ion battery of claim 13, wherein the positive electrode active material of the lithium ion battery is LiNi 0.8 Co 0.1 Mn 0.1 O 2 。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311818961.9A CN117477040A (en) | 2023-12-27 | 2023-12-27 | Electrolyte and lithium ion battery containing same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311818961.9A CN117477040A (en) | 2023-12-27 | 2023-12-27 | Electrolyte and lithium ion battery containing same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117477040A true CN117477040A (en) | 2024-01-30 |
Family
ID=89627806
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311818961.9A Pending CN117477040A (en) | 2023-12-27 | 2023-12-27 | Electrolyte and lithium ion battery containing same |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117477040A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117691191A (en) * | 2024-01-31 | 2024-03-12 | 南京理工大学 | Non-inflammable and high-voltage-resistant sultone-based lithium battery and electrolyte |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102738508A (en) * | 2011-04-11 | 2012-10-17 | 中国科学院过程工程研究所 | Lithium ion battery electrolyte with low lithium salt content |
| US20130029232A1 (en) * | 2011-07-25 | 2013-01-31 | Microvast New Materials (Huzhou) Co., LTD. | Lithium ion secondary battery including ionic liquid electrolyte |
| CN103996891A (en) * | 2013-02-19 | 2014-08-20 | 中国科学院宁波材料技术与工程研究所 | Lithium-air cell electrolyte solution system |
| JP2018181511A (en) * | 2017-04-07 | 2018-11-15 | トヨタ自動車株式会社 | Lithium ion secondary battery |
| CN109119692A (en) * | 2018-09-26 | 2019-01-01 | 烟台大学 | A kind of electrolyte adding deep congruent melting agent and the low temperature resistant lithium-sulfur cell comprising the electrolyte |
| CN109830643A (en) * | 2019-01-11 | 2019-05-31 | 蜂巢能源科技有限公司 | Reduce the film and its preparation method and application of lithium battery interface impedance |
| CN111600072A (en) * | 2020-05-29 | 2020-08-28 | 犀望新能源科技（昆山）有限公司 | Lithium battery electrolyte and preparation method and application thereof |
| CN113299997A (en) * | 2021-05-20 | 2021-08-24 | 惠州亿纬锂能股份有限公司 | Electrolyte for metal lithium battery and preparation method and application thereof |
| CN114792806A (en) * | 2022-05-19 | 2022-07-26 | 惠州亿纬锂能股份有限公司 | Lithium metal secondary electrolyte and lithium metal secondary battery |
| CN116231089A (en) * | 2023-03-24 | 2023-06-06 | 珠海中科先进技术研究院有限公司 | Local high-concentration ionic liquid modified electrolyte and preparation method and application thereof |
| CN116505081A (en) * | 2023-03-29 | 2023-07-28 | 中国科学院苏州纳米技术与纳米仿生研究所 | Electrolyte and sulfur-based lithium battery containing same |
-
2023
- 2023-12-27 CN CN202311818961.9A patent/CN117477040A/en active Pending
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102738508A (en) * | 2011-04-11 | 2012-10-17 | 中国科学院过程工程研究所 | Lithium ion battery electrolyte with low lithium salt content |
| US20130029232A1 (en) * | 2011-07-25 | 2013-01-31 | Microvast New Materials (Huzhou) Co., LTD. | Lithium ion secondary battery including ionic liquid electrolyte |
| CN103996891A (en) * | 2013-02-19 | 2014-08-20 | 中国科学院宁波材料技术与工程研究所 | Lithium-air cell electrolyte solution system |
| JP2018181511A (en) * | 2017-04-07 | 2018-11-15 | トヨタ自動車株式会社 | Lithium ion secondary battery |
| CN109119692A (en) * | 2018-09-26 | 2019-01-01 | 烟台大学 | A kind of electrolyte adding deep congruent melting agent and the low temperature resistant lithium-sulfur cell comprising the electrolyte |
| CN109830643A (en) * | 2019-01-11 | 2019-05-31 | 蜂巢能源科技有限公司 | Reduce the film and its preparation method and application of lithium battery interface impedance |
| CN111600072A (en) * | 2020-05-29 | 2020-08-28 | 犀望新能源科技（昆山）有限公司 | Lithium battery electrolyte and preparation method and application thereof |
| CN113299997A (en) * | 2021-05-20 | 2021-08-24 | 惠州亿纬锂能股份有限公司 | Electrolyte for metal lithium battery and preparation method and application thereof |
| CN114792806A (en) * | 2022-05-19 | 2022-07-26 | 惠州亿纬锂能股份有限公司 | Lithium metal secondary electrolyte and lithium metal secondary battery |
| CN116231089A (en) * | 2023-03-24 | 2023-06-06 | 珠海中科先进技术研究院有限公司 | Local high-concentration ionic liquid modified electrolyte and preparation method and application thereof |
| CN116505081A (en) * | 2023-03-29 | 2023-07-28 | 中国科学院苏州纳米技术与纳米仿生研究所 | Electrolyte and sulfur-based lithium battery containing same |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117691191A (en) * | 2024-01-31 | 2024-03-12 | 南京理工大学 | Non-inflammable and high-voltage-resistant sultone-based lithium battery and electrolyte |
| CN117691191B (en) * | 2024-01-31 | 2024-04-16 | 南京理工大学 | Non-inflammable and high-voltage-resistant sultone-based lithium battery and electrolyte |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110911752A (en) | Low-internal-resistance lithium secondary battery electrolyte and lithium secondary battery | |
| CN110600804B (en) | Lithium ion battery electrolyte suitable for NCM811 and SiO-C material system and preparation method thereof | |
| CN111883839B (en) | High-voltage electrolyte and lithium ion battery based on same | |
| CN109473719B (en) | Lithium ion battery electrolyte and lithium ion battery containing same | |
| US10840541B2 (en) | Pretreatment method for lithium electrode, and lithium metal battery | |
| CN107017432A (en) | Nonaqueous electrolytic solution and lithium ion battery | |
| CN111354978A (en) | High-voltage ternary lithium ion battery electrolyte and high-voltage ternary lithium ion battery | |
| CN111725575A (en) | High nickel lithium cell and car | |
| CN113437363A (en) | Non-aqueous electrolyte and secondary battery thereof | |
| CN114552006A (en) | Electrolyte additive composition and application | |
| CN117477040A (en) | Electrolyte and lithium ion battery containing same | |
| CN111900481A (en) | Electrolyte for high-nickel anode material lithium ion battery | |
| CN113206293A (en) | Lithium metal battery electrolyte and preparation method and application thereof | |
| CN113113668B (en) | Electrolyte additive, non-aqueous electrolyte containing electrolyte additive and lithium ion battery | |
| CN111384442A (en) | Film forming additive for battery electrolyte anode, electrolyte using film forming additive and lithium ion battery | |
| CN112086684B (en) | Cesium-containing high-voltage lithium ion battery electrolyte composite additive, electrolyte and battery thereof | |
| CN113346142B (en) | Low-concentration electrolyte for lithium ion secondary battery and lithium ion secondary battery | |
| CN111146497B (en) | Additive for battery electrolyte, lithium ion battery electrolyte and lithium ion battery | |
| CN113764728A (en) | Electrolyte and lithium metal battery | |
| CN110890590A (en) | Multifunctional high-voltage lithium ion battery electrolyte and high-voltage lithium ion battery | |
| CN111342133A (en) | Novel non-aqueous electrolyte for lithium ion battery and lithium ion battery | |
| CN113193229B (en) | Silicon-based electrolyte additive, electrolyte and lithium ion battery | |
| CN107681191A (en) | A kind of high-voltage lithium ion batteries | |
| CN117293392A (en) | Electrolyte with metal compensation function and application thereof | |
| CN110994025A (en) | Electrolyte additive, electrolyte and lithium ion battery |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |