CN116632350A - Electrolyte and battery comprising same - Google Patents
Electrolyte and battery comprising same Download PDFInfo
- Publication number
- CN116632350A CN116632350A CN202310742514.3A CN202310742514A CN116632350A CN 116632350 A CN116632350 A CN 116632350A CN 202310742514 A CN202310742514 A CN 202310742514A CN 116632350 A CN116632350 A CN 116632350A
- Authority
- CN
- China
- Prior art keywords
- electrolyte
- additive
- negative electrode
- silicon
- anode
- 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 117
- 239000000654 additive Substances 0.000 claims abstract description 144
- 230000000996 additive effect Effects 0.000 claims abstract description 126
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 44
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 44
- 239000010703 silicon Substances 0.000 claims abstract description 44
- 150000003839 salts Chemical class 0.000 claims abstract description 21
- 239000002904 solvent Substances 0.000 claims abstract description 9
- -1 1, 3-propylene sultone Chemical class 0.000 claims description 53
- OIFBSDVPJOWBCH-UHFFFAOYSA-N Diethyl carbonate Chemical compound CCOC(=O)OCC OIFBSDVPJOWBCH-UHFFFAOYSA-N 0.000 claims description 31
- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 claims description 31
- BTGRAWJCKBQKAO-UHFFFAOYSA-N adiponitrile Chemical compound N#CCCCCC#N BTGRAWJCKBQKAO-UHFFFAOYSA-N 0.000 claims description 31
- RUOJZAUFBMNUDX-UHFFFAOYSA-N propylene carbonate Chemical compound CC1COC(=O)O1 RUOJZAUFBMNUDX-UHFFFAOYSA-N 0.000 claims description 31
- LSNNMFCWUKXFEE-UHFFFAOYSA-M Bisulfite Chemical compound OS([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-M 0.000 claims description 24
- 239000007773 negative electrode material Substances 0.000 claims description 18
- 239000007774 positive electrode material Substances 0.000 claims description 18
- FSSPGSAQUIYDCN-UHFFFAOYSA-N 1,3-Propane sultone Chemical compound O=S1(=O)CCCO1 FSSPGSAQUIYDCN-UHFFFAOYSA-N 0.000 claims description 17
- UHOPWFKONJYLCF-UHFFFAOYSA-N 2-(2-sulfanylethyl)isoindole-1,3-dione Chemical compound C1=CC=C2C(=O)N(CCS)C(=O)C2=C1 UHOPWFKONJYLCF-UHFFFAOYSA-N 0.000 claims description 17
- 125000000217 alkyl group Chemical group 0.000 claims description 17
- 239000002131 composite material Substances 0.000 claims description 17
- 229910052736 halogen Inorganic materials 0.000 claims description 15
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 13
- 150000002367 halogens Chemical group 0.000 claims description 12
- 150000001336 alkenes Chemical class 0.000 claims description 10
- 150000001345 alkine derivatives Chemical class 0.000 claims description 10
- 239000010405 anode material Substances 0.000 claims description 10
- 150000004945 aromatic hydrocarbons Chemical class 0.000 claims description 9
- DKPFZGUDAPQIHT-UHFFFAOYSA-N butyl acetate Chemical compound CCCCOC(C)=O DKPFZGUDAPQIHT-UHFFFAOYSA-N 0.000 claims description 6
- OBNCKNCVKJNDBV-UHFFFAOYSA-N ethyl butyrate Chemical compound CCCC(=O)OCC OBNCKNCVKJNDBV-UHFFFAOYSA-N 0.000 claims description 6
- FKRCODPIKNYEAC-UHFFFAOYSA-N ethyl propionate Chemical compound CCOC(=O)CC FKRCODPIKNYEAC-UHFFFAOYSA-N 0.000 claims description 6
- MLFHJEHSLIIPHL-UHFFFAOYSA-N isoamyl acetate Chemical compound CC(C)CCOC(C)=O MLFHJEHSLIIPHL-UHFFFAOYSA-N 0.000 claims description 6
- PGMYKACGEOXYJE-UHFFFAOYSA-N pentyl acetate Chemical compound CCCCCOC(C)=O PGMYKACGEOXYJE-UHFFFAOYSA-N 0.000 claims description 6
- 229910052799 carbon Inorganic materials 0.000 claims description 5
- 239000006183 anode active material Substances 0.000 claims description 4
- 125000004430 oxygen atom Chemical group O* 0.000 claims description 4
- 125000004434 sulfur atom Chemical group 0.000 claims description 4
- VWEYDBUEGDKEHC-UHFFFAOYSA-N 3-methyloxathiolane 2,2-dioxide Chemical compound CC1CCOS1(=O)=O VWEYDBUEGDKEHC-UHFFFAOYSA-N 0.000 claims description 3
- JGFBQFKZKSSODQ-UHFFFAOYSA-N Isothiocyanatocyclopropane Chemical compound S=C=NC1CC1 JGFBQFKZKSSODQ-UHFFFAOYSA-N 0.000 claims description 3
- PWLNAUNEAKQYLH-UHFFFAOYSA-N butyric acid octyl ester Natural products CCCCCCCCOC(=O)CCC PWLNAUNEAKQYLH-UHFFFAOYSA-N 0.000 claims description 3
- 150000004649 carbonic acid derivatives Chemical class 0.000 claims description 3
- 150000007942 carboxylates Chemical class 0.000 claims description 3
- 150000001733 carboxylic acid esters Chemical class 0.000 claims description 3
- IEJIGPNLZYLLBP-UHFFFAOYSA-N dimethyl carbonate Chemical compound COC(=O)OC IEJIGPNLZYLLBP-UHFFFAOYSA-N 0.000 claims description 3
- 150000002148 esters Chemical class 0.000 claims description 3
- JBTWLSYIZRCDFO-UHFFFAOYSA-N ethyl methyl carbonate Chemical compound CCOC(=O)OC JBTWLSYIZRCDFO-UHFFFAOYSA-N 0.000 claims description 3
- GJRQTCIYDGXPES-UHFFFAOYSA-N iso-butyl acetate Natural products CC(C)COC(C)=O GJRQTCIYDGXPES-UHFFFAOYSA-N 0.000 claims description 3
- FGKJLKRYENPLQH-UHFFFAOYSA-M isocaproate Chemical compound CC(C)CCC([O-])=O FGKJLKRYENPLQH-UHFFFAOYSA-M 0.000 claims description 3
- OQAGVSWESNCJJT-UHFFFAOYSA-N isovaleric acid methyl ester Natural products COC(=O)CC(C)C OQAGVSWESNCJJT-UHFFFAOYSA-N 0.000 claims description 3
- YKYONYBAUNKHLG-UHFFFAOYSA-N n-Propyl acetate Natural products CCCOC(C)=O YKYONYBAUNKHLG-UHFFFAOYSA-N 0.000 claims description 3
- UUIQMZJEGPQKFD-UHFFFAOYSA-N n-butyric acid methyl ester Natural products CCCC(=O)OC UUIQMZJEGPQKFD-UHFFFAOYSA-N 0.000 claims description 3
- MHYFEEDKONKGEB-UHFFFAOYSA-N oxathiane 2,2-dioxide Chemical compound O=S1(=O)CCCCO1 MHYFEEDKONKGEB-UHFFFAOYSA-N 0.000 claims description 3
- 229940090181 propyl acetate Drugs 0.000 claims description 3
- 238000000926 separation method Methods 0.000 claims description 3
- IAHFWCOBPZCAEA-UHFFFAOYSA-N succinonitrile Chemical compound N#CCCC#N IAHFWCOBPZCAEA-UHFFFAOYSA-N 0.000 claims description 3
- NQPDZGIKBAWPEJ-UHFFFAOYSA-N valeric acid Chemical compound CCCCC(O)=O NQPDZGIKBAWPEJ-UHFFFAOYSA-N 0.000 claims description 3
- 125000005843 halogen group Chemical group 0.000 claims 2
- 125000002029 aromatic hydrocarbon group Chemical group 0.000 claims 1
- 230000015572 biosynthetic process Effects 0.000 abstract description 10
- 150000001875 compounds Chemical class 0.000 abstract description 5
- HMDDXIMCDZRSNE-UHFFFAOYSA-N [C].[Si] Chemical compound [C].[Si] HMDDXIMCDZRSNE-UHFFFAOYSA-N 0.000 abstract description 4
- 239000000463 material Substances 0.000 abstract description 4
- 238000010276 construction Methods 0.000 abstract description 3
- 229920000642 polymer Polymers 0.000 abstract description 3
- 239000002210 silicon-based material Substances 0.000 abstract description 3
- 238000002360 preparation method Methods 0.000 description 45
- 229910013872 LiPF Inorganic materials 0.000 description 15
- 101150058243 Lipf gene Proteins 0.000 description 15
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 15
- 229910001416 lithium ion Inorganic materials 0.000 description 15
- 239000003960 organic solvent Substances 0.000 description 15
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 14
- XBDQKXXYIPTUBI-UHFFFAOYSA-M Propionate Chemical compound CCC([O-])=O XBDQKXXYIPTUBI-UHFFFAOYSA-M 0.000 description 14
- 229910052744 lithium Inorganic materials 0.000 description 14
- 238000012360 testing method Methods 0.000 description 10
- 239000011230 binding agent Substances 0.000 description 7
- 230000000052 comparative effect Effects 0.000 description 7
- 239000006258 conductive agent Substances 0.000 description 7
- 238000011056 performance test Methods 0.000 description 7
- 238000003860 storage Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 238000002156 mixing Methods 0.000 description 4
- 239000002002 slurry Substances 0.000 description 4
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 3
- 239000002041 carbon nanotube Substances 0.000 description 3
- 229910021393 carbon nanotube Inorganic materials 0.000 description 3
- 238000004880 explosion Methods 0.000 description 3
- 239000011888 foil Substances 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 229910002804 graphite Inorganic materials 0.000 description 3
- 239000010439 graphite Substances 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- BTBUEUYNUDRHOZ-UHFFFAOYSA-N Borate Chemical compound [O-]B([O-])[O-] BTBUEUYNUDRHOZ-UHFFFAOYSA-N 0.000 description 2
- 229920000049 Carbon (fiber) Polymers 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 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
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 2
- ZVLDJSZFKQJMKD-UHFFFAOYSA-N [Li].[Si] Chemical compound [Li].[Si] ZVLDJSZFKQJMKD-UHFFFAOYSA-N 0.000 description 2
- DPXJVFZANSGRMM-UHFFFAOYSA-N acetic acid;2,3,4,5,6-pentahydroxyhexanal;sodium Chemical compound [Na].CC(O)=O.OCC(O)C(O)C(O)C(O)C=O DPXJVFZANSGRMM-UHFFFAOYSA-N 0.000 description 2
- 230000009471 action Effects 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 2
- 229910021383 artificial graphite Inorganic materials 0.000 description 2
- 239000004917 carbon fiber Substances 0.000 description 2
- 239000001768 carboxy methyl cellulose Substances 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 239000011889 copper foil Substances 0.000 description 2
- 125000004122 cyclic group Chemical group 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 239000008151 electrolyte solution Substances 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 229910000625 lithium cobalt oxide Inorganic materials 0.000 description 2
- 229910001947 lithium oxide Inorganic materials 0.000 description 2
- 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 description 2
- BFZPBUKRYWOWDV-UHFFFAOYSA-N lithium;oxido(oxo)cobalt Chemical compound [Li+].[O-][Co]=O BFZPBUKRYWOWDV-UHFFFAOYSA-N 0.000 description 2
- 230000014759 maintenance of location Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 238000004806 packaging method and process Methods 0.000 description 2
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 229910000077 silane Inorganic materials 0.000 description 2
- 239000002109 single walled nanotube Substances 0.000 description 2
- 235000019812 sodium carboxymethyl cellulose Nutrition 0.000 description 2
- 229920001027 sodium carboxymethylcellulose Polymers 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 229920003048 styrene butadiene rubber Polymers 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 230000002195 synergetic effect Effects 0.000 description 2
- 229910052723 transition metal Inorganic materials 0.000 description 2
- 229910018040 Li 1+x Ni Inorganic materials 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 229920003171 Poly (ethylene oxide) Polymers 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 239000002174 Styrene-butadiene Substances 0.000 description 1
- OBNDGIHQAIXEAO-UHFFFAOYSA-N [O].[Si] Chemical compound [O].[Si] OBNDGIHQAIXEAO-UHFFFAOYSA-N 0.000 description 1
- 239000006230 acetylene black Substances 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- MTAZNLWOLGHBHU-UHFFFAOYSA-N butadiene-styrene rubber Chemical compound C=CC=C.C=CC1=CC=CC=C1 MTAZNLWOLGHBHU-UHFFFAOYSA-N 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 125000004093 cyano group Chemical group *C#N 0.000 description 1
- 230000001351 cycling effect Effects 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 239000008367 deionised water Substances 0.000 description 1
- 229910021641 deionized water Inorganic materials 0.000 description 1
- QHGJSLXSVXVKHZ-UHFFFAOYSA-N dilithium;dioxido(dioxo)manganese Chemical compound [Li+].[Li+].[O-][Mn]([O-])(=O)=O QHGJSLXSVXVKHZ-UHFFFAOYSA-N 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910021385 hard carbon Inorganic materials 0.000 description 1
- 150000003949 imides Chemical class 0.000 description 1
- 230000002687 intercalation Effects 0.000 description 1
- 238000009830 intercalation Methods 0.000 description 1
- 239000003273 ketjen black Substances 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 229920000126 latex Polymers 0.000 description 1
- 239000004816 latex Substances 0.000 description 1
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 description 1
- 229910003002 lithium salt Inorganic materials 0.000 description 1
- 159000000002 lithium salts Chemical class 0.000 description 1
- 229910001496 lithium tetrafluoroborate Inorganic materials 0.000 description 1
- ACFSQHQYDZIPRL-UHFFFAOYSA-N lithium;bis(1,1,2,2,2-pentafluoroethylsulfonyl)azanide Chemical compound [Li+].FC(F)(F)C(F)(F)S(=O)(=O)[N-]S(=O)(=O)C(F)(F)C(F)(F)F ACFSQHQYDZIPRL-UHFFFAOYSA-N 0.000 description 1
- IGILRSKEFZLPKG-UHFFFAOYSA-M lithium;difluorophosphinate Chemical compound [Li+].[O-]P(F)(F)=O IGILRSKEFZLPKG-UHFFFAOYSA-M 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000000873 masking effect Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000004005 microsphere Substances 0.000 description 1
- 229910021382 natural graphite Inorganic materials 0.000 description 1
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 description 1
- 238000006864 oxidative decomposition reaction Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 239000010452 phosphate Substances 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910021384 soft carbon Inorganic materials 0.000 description 1
- 239000011115 styrene butadiene Substances 0.000 description 1
- 238000009461 vacuum packaging Methods 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
- 229910052726 zirconium Inorganic materials 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
- H01M10/0567—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
- H01M10/052—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
- H01M10/058—Construction or manufacture
-
- 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
Abstract
The invention provides an electrolyte and a battery comprising the same, wherein the electrolyte comprises the following components: an electrolyte salt, a solvent, a first additive, and a second additive; the Si in the first additive structural formula can be combined with the HF in the electrolyte to remove the HF in the electrolyte, so that the stability of the anode-cathode interface is improved. When the anode is a silicon-carbon anode, the silicon element in the first additive can be well compatible with silicon doped in the anode, and the anode participates in the construction of the SEI film in the formation stage, and the formed polymer network can effectively inhibit the volume expansion of the silicon material, so that the circulation stability of the material is improved. When the negative electrode contains more F-substituted compound, the second additive can be further reduced on the surface of the negative electrode to generate more LiF, so that a low-impedance battery is obtained.
Description
Technical Field
The invention relates to the technical field of electrolyte, in particular to electrolyte and a battery comprising the same.
Background
Lithium ion batteries are widely used in various electronic products due to their advantages of high specific energy density, long cycle life, and the like, and have been widely used in electric vehicles, various electric tools, and energy storage devices thereof in recent years. Along with the expansion of the application range of lithium ion batteries, the size of the batteries is also increased, and the requirement for improving the energy density of the batteries is also increased, and meanwhile, the safety performance of the batteries is also required to be ensured.
In order to increase the energy density of the battery, it is a common path to further increase the voltage of the positive electrode material of the lithium ion battery. However, as the limiting voltage of the positive electrode material increases, the gram capacity of the positive electrode material gradually increases, and the high temperature performance of the battery is seriously deteriorated, and the long cycle life cannot be ensured. Especially under high voltage, the volume of the positive electrode material expands and causes serious cracks in the long-term cyclic charge and discharge process, electrolyte enters the positive electrode material to damage the structure of the positive electrode material, and meanwhile, the release of active oxygen further accelerates the oxidative decomposition of the electrolyte. In addition, the ultra-high gram capacity of the silicon anode material can also improve the energy density of the battery, but silicon is easy to cause more side reactions of electrolyte on the surface due to easy breakage of surface particles and large volume expansion rate, and finally the problem of serious attenuation of the battery capacity is caused.
Disclosure of Invention
In view of the above, the present invention provides an electrolyte and a battery including the same, wherein the electrolyte includes a first additive and a second additive, and when the second additive cooperates with the first additive to act on the surface of a negative electrode together, a tightly repairable SEI structure layer can be formed without increasing impedance, and the two additives cooperate to protect the positive electrode and the negative electrode together.
In order to solve the technical problems in the background technology, the invention adopts the following technical scheme:
in a first aspect, the present invention provides an electrolyte, including:
an electrolyte salt, a solvent, a first additive, and a second additive;
the structural formula of the first additive is shown as formula (1):
x is independently selected from any one of O atom, S atom, -NH-, -PH-or-BH-; n is any natural number from 0 to 6; r is R 1 Each independently selected from the group consisting of alkyl, alkene, alkyne and aromatic hydrocarbon, or any one of the alkyl, alkene, alkyne and aromatic hydrocarbon substituted by halogen;
the structural formula of the second additive is shown as formula (2):
R 2 is a null bond or-CH 2 -, said R 2 R is represented by a null bond 3 、R 4 The two are connected through a single bond; r is R 3 、R 4 Each independently selected from at least one of halogen, alkyl, and alkyl substituted with halogen.
Further, the addition amount of the first additive is 0.1-10.0 wt% of the total mass of the electrolyte.
Further, the addition amount of the second additive is 5.0-25.0 wt% of the total mass of the electrolyte.
Further, the first additive includes any one of structural formulas 1-1 to 1-12:
further, the second additive includes any one of structural formulas 2-1 to 2-6:
further, the solvent includes: carbonates and/or carboxylates; the carbonic ester comprises at least one of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate and methyl ethyl carbonate; the carboxylic acid ester comprises at least one of propyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl acetate, isopentyl acetate, propyl propionate, ethyl propionate, methyl butyrate and ethyl n-butyrate.
Further, the electrolyte further comprises: sulfonic acid additives; the sulfonic acid additive comprises at least one of 1, 3-propane sultone, 1-propylene-1, 3-sultone, 5-methyl oxathiapentane 2, 2-dioxide, 1, 3-propylene sultone, 2, 4-butane sultone and 1, 4-butane sultone; and/or the electrolyte further comprises: nitrile compounds; the nitrile compound comprises at least one of adiponitrile, succinonitrile and 1,3, 6-hexanetrinitrile.
In a second aspect, the present invention provides a battery, including: an electrolyte as described above; a positive electrode sheet containing a positive electrode active material; a negative electrode sheet containing a negative electrode active material; and a separation film.
Further, the anode active material includes a silicon composite material and a carbon-based anode material.
Further, the percentage of silicon element in the anode material to the total mass of the anode material is A percent, the addition of the first additive to the total mass of the electrolyte is B percent, and the addition of the second additive to the total mass of the electrolyte is C percent; wherein, the value range of A is 1-25, the value range of B is 0.1-10, and the value range of C is 5-25; A. b, C satisfy the following relationship:
0.12≤(B+C/10)/A≤3。
the technical scheme of the invention has the following beneficial effects:
the invention provides an electrolyte and a battery comprising the same, wherein the electrolyte comprises the following components: an electrolyte salt, a solvent, a first additive, and a second additive; the structural formula of the first additive is shown as formula (1):
x is independently selected from any one of O atom, S atom, -NH-, -PH-or-BH-; n is any natural number from 0 to 6; r is R 1 Each independently selected from the group consisting of alkyl, alkene, alkyne and aromatic hydrocarbon, or any one of the alkyl, alkene, alkyne and aromatic hydrocarbon substituted by halogen;
the structural formula of the second additive is shown as formula (2):
the R is 2 Is a null bond or-CH 2 -, said R 2 R is represented by a null bond 3 、R 4 The two are connected through a single bond; the R is 3 、R 4 Each independently selected from at least one of halogen, alkyl, and alkyl substituted with halogen.
The first additive in the electrolyte is a silane-containing compound, and Si in the structural formula of the first additive can be combined with HF in the electrolyte to remove the HF in the electrolyte. In addition, the first additive can participate in reduction on the surface of the negative electrode to generate an SEI film, so that the negative electrode is protected. Especially when the anode is a silicon-carbon anode, the silicon element in the first additive can be well compatible with silicon doped in the anode, and the anode participates in the construction of the SEI film in the formation stage, and the formed polymer network can effectively inhibit the volume expansion of the silicon material, so that the circulation stability of the material is improved. Further, the first additive can be polymerized to form a film on the surface of the positive electrode, so that the effect of protecting the positive electrode plate is achieved. When the negative electrode contains more F-substituted compound, the second additive can be further reduced on the surface of the negative electrode to generate more LiF, so that a low-impedance battery is obtained. When the second additive and the first additive act on the surface of the negative electrode together, the electrolyte provided by the invention can form a compact repairable SEI structure layer without increasing impedance, and the positive electrode and the negative electrode are protected together by the synergistic effect of the second additive and the first additive, so that the electrolyte is prevented from being further decomposed, and the quick-charge stability of the electrolyte is improved.
Drawings
FIG. 1 is a structural formula of a first additive in an electrolyte;
fig. 2 is a structural formula of a second additive in an electrolyte.
Detailed Description
For a further understanding of the present invention, preferred embodiments of the invention are described below in conjunction with the examples, but it is to be understood that these descriptions are merely intended to illustrate further the features and advantages of the invention and are not limiting of the invention.
The electrolyte solution and the battery including the same in the present invention are further explained below with reference to specific examples.
In a first aspect, the present invention provides an electrolyte, including:
an electrolyte salt, a solvent, a first additive, and a second additive;
the structural formula of the first additive is shown as formula (1):
x is independently selected from any one of O atom, S atom, -NH-, -PH-or-BH-; n is any natural number from 0 to 6; r is R 1 Each independently selected from the group consisting of alkyl, alkene, alkyne and aromatic hydrocarbon, or any one of the alkyl, alkene, alkyne and aromatic hydrocarbon substituted by halogen;
the structural formula of the second additive is shown as formula (2):
R 2 is a null bond or-CH 2 -, said R 2 R is represented by a null bond 3 、R 4 The two are connected through a single bond; r is R 3 、R 4 Each independently selected from at least one of halogen, alkyl, and alkyl substituted with halogen.
According to some embodiments of the invention, the R 1 When alkyl, it may be-CH 3 、-CH 2 CH 3 、-CH 2 CH 2 CH 3 、-(CH 2 ) 3 CH 3 、-(CH 2 ) 4 CH 3 、-(CH 2 ) 5 CH 3 、-(CH 2 ) 6 CH 3 、-(CH 2 ) 7 CH 3 、-(CH 2 ) 8 CH 3 、-(CH 2 ) 9 CH 3 、-(CH 2 ) 10 CH 3 The method comprises the steps of carrying out a first treatment on the surface of the When R is 1 In the case of olefins, it may be-CH=CH 3 、-CH 2 -CH＝CH 3 、-(CH 2 ) 2 -CH＝CH 3 、-(CH 2 ) 3 -CH＝CH 3 、-(CH 2 ) 4 -CH＝CH 3 、-(CH 2 ) 5 -CH＝CH 3 、-(CH 2 ) 6 -CH＝CH 3 、-(CH 2 ) 7 -CH＝CH 3 、-(CH 2 ) 8 -CH＝CH 3 、-(CH 2 ) 9 -CH＝CH 3 、-(CH 2 ) 10 -CH＝CH 3 The method comprises the steps of carrying out a first treatment on the surface of the When R is 1 In the case of alkynes, they may be-C.ident.CH, -CH 2 -C≡CH、-(CH 2 ) 2 -C≡CH、-(CH 2 ) 3 -C≡CH、-(CH 2 ) 4 -C≡CH、-(CH 2 ) 5 -C≡CH、-(CH 2 ) 6 -C≡CH、-(CH 2 ) 7 -C≡CH、-(CH 2 ) 8 -C≡CH、-(CH 2 ) 9 -C≡CH、-(CH 2 ) 10 -c≡ch; when R is 1 In the case of aromatic hydrocarbons, it may be-C 6 H 5 、-CH 2 C 6 H 5 、-(CH 2 ) 2 C 6 H 5 、-(CH 2 ) 3 C 6 H 5 、-(CH 2 ) 4 C 6 H 5 、-(CH 2 ) 5 C 6 H 5 、-(CH 2 ) 6 C 6 H 5 、-(CH 2 ) 7 C 6 H 5 、-(CH 2 ) 8 C 6 H 5 、-(CH 2 ) 9 C 6 H 5 、-(CH 2 ) 10 C 6 H 5 . When R is halogen substituted alkyl, it is preferably-CH 2 F、-CH 2 CH 2 F、-CH 2 CH 2 CH 2 F、-(CH 2 ) 3 CH 2 F、-(CH 2 ) 4 CH 2 F、-(CH 2 ) 5 CH 2 F、-(CH 2 ) 6 CH 2 F、-(CH 2 ) 7 CH 2 F、-(CH 2 ) 8 CH 2 F、-(CH 2 ) 9 CH 2 F、-(CH 2 ) 10 CH 2 F, when R is a halogen substituted olefin, is preferably-ch=ch 2 F、-CH 2 -CH＝CH 2 F、-(CH 2 ) 2 -CH＝CH 2 F、-(CH 2 ) 3 -CH＝CH 2 F、-(CH 2 ) 4 -CH＝CH 2 F、-(CH 2 ) 5 -CH＝CH 2 F、-(CH 2 ) 6 -CH＝CH 2 F、-(CH 2 ) 7 -CH＝CH 2 F、-(CH 2 ) 8 -CH＝CH 2 F、-(CH 2 ) 9 -CH＝CH 2 F、-(CH 2 ) 10 -CH＝CH 2 F, when R is a halogen substituted alkyne, it may be-C.ident.CF, -CH 2 -C≡CF、-(CH 2 ) 2 -C≡CF、-(CH 2 ) 3 -C≡CF、-(CH 2 ) 4 -C≡CF、-(CH 2 ) 5 -C≡CF、-(CH 2 ) 6 -C≡CF、-(CH 2 ) 7 -C≡CF、-(CH 2 ) 8 -C≡CF、-(CH 2 ) 9 -C≡CF、-(CH 2 ) 10 -c≡cf; when R is an aromatic hydrocarbon, it may be-C 6 H 4 F、-CH 2 C 6 H 4 F、-(CH 2 ) 2 C 6 H 4 F、-(CH 2 ) 3 C 6 H 4 F、-(CH 2 ) 4 C 6 H 4 F、-(CH 2 ) 5 C 6 H 4 F、-(CH 2 ) 6 C 6 H 4 F、-(CH 2 ) 7 C 6 H 4 F、-(CH 2 ) 8 C 6 H 4 F、-(CH 2 ) 9 C 6 H 4 F、-(CH 2 ) 10 C 6 H 4 F。
Aiming at the technical problems in the prior art, the invention provides an electrolyte and a battery containing the same, wherein the electrolyte comprises electrolyte salt, a solvent, a first additive and a second additive, the first additive is a silane-containing compound, the structure of the first additive is shown as a formula (1), si in the structural formula of the first additive can be combined with HF in the electrolyte, and the Si can be used for removing HF in the electrolyte, so that the stability of an anode-cathode interface is improved. In addition, the first additive can participate in reduction on the surface of the negative electrode to generate an SEI film, so that the negative electrode is protected. Especially when the anode is a silicon-carbon anode, the silicon element in the first additive can be well compatible with silicon doped in the anode, and the anode participates in the construction of the SEI film in the formation stage, and the formed polymer network can effectively inhibit the volume expansion of the silicon material, so that the circulation stability of the material is improved. When the negative electrode contains more F substituted compounds, the second additive can be further reduced on the surface of the negative electrode to generate more LiF, so that a battery with low impedance is obtained. When the second additive and the first additive act on the surface of the negative electrode together, the electrolyte provided by the invention can form a compact repairable SEI structure layer without increasing impedance, and the positive electrode and the negative electrode are protected together by the synergistic effect of the second additive and the first additive, so that the electrolyte is prevented from being further decomposed, and the quick-charge stability of the electrolyte is improved.
According to some embodiments of the invention, the first additive is added in an amount of 0.1wt% to 10.0wt% of the total mass of the electrolyte. Specifically, the first additive may be added in an amount of 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1wt%, 1.2wt%, 1.3wt%, 1.5wt%, 1.6wt%, 1.8wt%, 2wt%, 2.2wt%, 2.4wt%, 2.5wt%, 2.6wt%, 2.8wt%, 3wt%, 3.3wt%, 3.5wt%, 3.8wt%, 4wt%, 4.2wt%, 4.5wt%, 4.8wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt% and 10wt%.
According to some embodiments of the invention, the second additive is added in an amount of 5.0wt% to 25.0wt% of the total mass of the electrolyte. Specifically, the second additive may be added in an amount of 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, 18wt%, 19wt%, 20wt%, 21wt%, 22wt%, 23wt%, 24wt% and 25wt%.
According to some embodiments of the invention, the first additive comprises any one of formulas 1-1 to 1-12:
according to some embodiments of the invention, the second additive comprises any one of formulas 2-1 to 2-6:
according to some embodiments of the invention, the solvent comprises: carbonates and/or carboxylates; the carbonic ester comprises at least one of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate and methyl ethyl carbonate; the carboxylic acid ester comprises at least one of propyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl acetate, isopentyl acetate, propyl propionate, ethyl propionate, methyl butyrate and ethyl n-butyrate.
According to some embodiments of the invention, the electrolyte further comprises: sulfonic acid additives; the sulfonic acid additive comprises at least one of 1, 3-propane sultone, 1-propylene-1, 3-sultone, 5-methyl oxathiapentane 2, 2-dioxide, 1, 3-propylene sultone, 2, 4-butane sultone and 1, 4-butane sultone.
According to some embodiments of the invention, the electrolyte further comprises: nitrile compounds; the nitrile compound comprises at least one of adiponitrile, succinonitrile and 1,3, 6-hexanetrinitrile
In the present invention, when the first additive, the second additive, the sulfonic acid additive and the nitrile compound are used together, the positive and negative electrodes of the battery can be protected together in different aspects in cooperation with each other. The sulfonic acid additive can help to form a film on the negative electrode in the electrolyte, so that the gas production on the surface of the negative electrode can be influenced to a large extent, and the residual sulfonic acid additive in the electrolyte can well inhibit the generation of gas in high-temperature storage, thereby achieving the effects of reducing battery circulation and storing the gas production. The bond energy of the carbon-nitrogen triple bond in the nitrile compound is very high, so that the nitrile compound has very good stability and very strong oxidation resistance on the anode. Meanwhile, cyano has stronger coordination capability, can be combined with active sites on the surface of an electrode, and plays a role in masking active ions on the surface of a positive electrode, so that the decomposition effect of the electrode on electrolyte is reduced. On the positive electrode, the nitrile compound is stable and can complex active ions, so that the nitrile compound can enhance the resistance of the electrolyte to the oxidation of the positive electrode, thereby prolonging the cycle life of the battery under high voltage.
According to some embodiments of the invention, the electrolyte salt in the electrolyte solution comprises at least one of lithium hexafluorophosphate, lithium difluorophosphate, lithium difluorooxalato borate, lithium bistrifluoromethylsulfonyl imide, lithium difluorobisoxalato phosphate, lithium tetrafluoroborate, lithium bisoxalato borate, lithium hexafluoroantimonate, lithium hexafluoroarsenate, lithium bis (trifluoromethylsulfonyl) imide, lithium bis (pentafluoroethylsulfonyl) imide, lithium tris (trifluoromethylsulfonyl) methyl lithium, and lithium bis (trifluoromethylsulfonyl) imide. For example, the lithium salt may be lithium hexafluorophosphate.
In a second aspect, the present invention provides a battery, including: an electrolyte as described above; a positive electrode sheet containing a positive electrode active material; a negative electrode sheet containing a negative electrode active material; and a separation film.
According to other embodiments of the present invention, the positive electrode sheet includes a positive electrode current collector and a positive electrode active material layer coated on one side or both sides of the positive electrode current collector, the positive electrode active material layer including a positive electrode active material, a conductive agent, and a binder.
According to other embodiments of the present invention, the positive electrode active material layer comprises the following components in percentage by mass: 80-99.8wt% of positive electrode active material, 0.1-10wt% of conductive agent, and 0.1-10wt% of binder. Preferably, the positive electrode active material layer comprises the following components in percentage by mass: 90-99.6wt% of positive electrode active material, 0.2-5wt% of conductive agent, and 0.2-5wt% of binder.
According to other embodiments of the present invention, the negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer coated on one or both side surfaces of the negative electrode current collector, the negative electrode active material layer including a negative electrode active material, a conductive agent, and a binder.
According to other embodiments of the present invention, the mass percentage of each component in the negative electrode active material layer is: 80-99.8wt% of negative electrode active material, 0.1-10wt% of conductive agent, and 0.1-10wt% of binder. Preferably, the mass percentage of each component in the anode active material layer is as follows: 90-99.6wt% of negative electrode active material, 0.2-5wt% of conductive agent, and 0.2-5wt% of binder.
According to other embodiments of the present invention, the positive electrode active material is selected from one or more of transition metal lithium oxide, lithium iron phosphate, lithium manganate; the chemical formula of the transition metal lithium oxide is Li 1+x Ni y Co z M (1-y-z) O 2 Wherein, -0.1 is less than or equal to x is less than or equal to 1; y is more than or equal to 0 and less than or equal to 1, z is more than or equal to 0 and less than or equal to 1, and y+z is more than or equal to 0 and less than or equal to 1; wherein M is one or more of Mg, zn, ga, ba, al, fe, cr, sn, V, mn, sc, ti, nb, mo and Zr.
According to other embodiments of the present invention, the anode active material includes a silicon composite material and a carbon-based anode material. Further, the silicon composite material is at least one of graphite doped silicon carbon and graphite doped silicon oxide. The carbon-based negative electrode material comprises at least one of artificial graphite, natural graphite, mesophase carbon microspheres, hard carbon and soft carbon.
According to other embodiments of the present invention, the conductive agent is at least one selected from the group consisting of conductive carbon black, acetylene black, ketjen black, conductive graphite, conductive carbon fiber, carbon nanotube, metal powder, and carbon fiber.
According to other embodiments of the present invention, the binder is at least one selected from sodium carboxymethyl cellulose, styrene-butadiene latex, polytetrafluoroethylene, polyethylene oxide.
According to other embodiments of the present invention, the percentage of silicon element in the negative electrode material is a% of the total mass of the negative electrode material, the addition amount of the first additive is B% of the total mass of the electrolyte, and the addition amount of the second additive is C% of the total mass of the electrolyte; wherein, the value range of A is 1-25, the value range of B is 0.1-10, and the value range of C is 5-25; A. b, C satisfy the following relationship:
0.12≤(B+C/10)/A≤3。
according to other embodiments of the present invention, the lithium content of the anode material after the first formation is D%, and the following relationship is satisfied between a and D:
0≤D/A≤0.05。
the first formation conditions are as follows: charging at 70deg.C under high temperature and high pressure of 600kgf for 30min at 0.1C for 30min at 0.5C and 45min at 0.7C.
The inventor finds that the silicon content in the anode material has a certain correlation with the dosage of the first additive and the second additive in the electrolyte through experimental study. Specifically, the percentage of silicon element in the silicon composite material accounting for the total mass of the anode material is A percent, the addition of the first additive accounts for the percentage of the total mass of the electrolyte to be B percent, and the addition of the second additive accounts for the percentage of the total mass of the electrolyte to be C percent; A. b, C satisfy the following relationship: the ratio of (B+C/10)/A is more than or equal to 0.12 and less than or equal to 3, which is beneficial to improving the thickness expansion and the cycle stability of the battery. Meanwhile, the negative electrode material contains lithium in different amounts according to different raw materials, lithium remains in a silicon negative electrode and SEI after the prepared battery is subjected to first lithium intercalation formation, and the lithium content of a negative electrode sheet after formation is measured to be D percent, and when the following relation is satisfied between A and D: D/A is more than or equal to 0 and less than or equal to 0.05, which is beneficial to improving the thickness expansion and the cycling stability of the battery.
The invention is further illustrated by the following examples.
Example 1
Preparation of electrolyte
1.1 the electrolyte comprises the following components:
organic solvent: 7wt% of Ethylene Carbonate (EC), 7wt% of Propylene Carbonate (PC), 14wt% of diethyl carbonate (DEC) and 39wt% of Propyl Propionate (PP), which are 67wt% in total;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
A first additive: structural formula 1-1;0.5wt%;
and a second additive: structural formula 2-1;10wt%;
nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 in an argon-filled glove box (H 2 O<0.1ppm，O 2 <0.1 ppm), adding and mixing the organic solvent according to the proportion, and rapidly adding 1mol/L of fully dried lithium hexafluorophosphate (LiPF) 6 ) And (3) fully mixing and shaking uniformly, adding the first additive, the second additive, the nitrile compound and the sulfonic acid additive uniformly, and stirring uniformly to obtain the required electrolyte.
Example 2
1.1 the electrolyte comprises the following components:
organic solvent: 7wt% of Ethylene Carbonate (EC), 7wt% of Propylene Carbonate (PC), 14wt% of diethyl carbonate (DEC) and 38.5wt% of Propyl Propionate (PP), which amounts to 66.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
A first additive: structural formula 1-1;1wt%;
and a second additive: structural formula 2-1;10wt%;
nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method: the same as in example 1.
Example 3
1.1 the electrolyte comprises the following components:
organic solvent: 7wt% of Ethylene Carbonate (EC), 7wt% of Propylene Carbonate (PC), 14wt% of diethyl carbonate (DEC) and 36.5wt% of Propyl Propionate (PP), which amounts to 64.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
A first additive: structural formula 1-1;3wt%;
and a second additive: structural formula 2-1;10wt%.
Nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method: the same as in example 1.
Example 4
1.1 the electrolyte comprises the following components:
organic solvent: 6wt% of Ethylene Carbonate (EC), 6wt% of Propylene Carbonate (PC), 12wt% of diethyl carbonate (DEC) and 36.5wt% of Propyl Propionate (PP), which amounts to 60.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
A first additive: structural formula 1-1;7wt%;
and a second additive: structural formula 2-1;10wt%;
nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method: the same as in example 1.
Example 5
1.1 the electrolyte comprises the following components:
organic solvent: 6wt% of Ethylene Carbonate (EC), 6wt% of Propylene Carbonate (PC), 12wt% of diethyl carbonate (DEC) and 33.5wt% of Propyl Propionate (PP), which amounts to 57.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
A first additive: structural formula 1-1;10wt%;
and a second additive: structural formula 2-1;10wt%;
nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method: the same as in example 1.
Example 6
1.1 the electrolyte comprises the following components:
organic solvent: 7wt% of Ethylene Carbonate (EC), 7wt% of Propylene Carbonate (PC), 14wt% of diethyl carbonate (DEC) and 41.5wt% of Propyl Propionate (PP), which amounts to 69.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
A first additive: structural formula 1-1;1wt%;
and a second additive: structural formula 2-1;7wt%;
nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method: the same as in example 1.
Example 7
1.1 the electrolyte comprises the following components:
organic solvent: 6wt% of Ethylene Carbonate (EC), 6wt% of Propylene Carbonate (PC), 12wt% of diethyl carbonate (DEC) and 37.5wt% of Propyl Propionate (PP), which amounts to 61.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
A first additive: structural formula 1-1;1wt%;
and a second additive: structural formula 2-1;15wt%;
nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method: the same as in example 1.
Example 8
1.1 the electrolyte comprises the following components:
organic solvent: 6wt% of Ethylene Carbonate (EC), 6wt% of Propylene Carbonate (PC), 12wt% of diethyl carbonate (DEC) and 32.5wt% of Propyl Propionate (PP), which amounts to 56.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
A first additive: structural formula 1-1;1wt%;
and a second additive: structural formula 2-1;20wt%;
nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method: the same as in example 1.
Example 9
1.1 the electrolyte comprises the following components:
organic solvent: 6wt% of Ethylene Carbonate (EC), 6wt% of Propylene Carbonate (PC), 12wt% of diethyl carbonate (DEC) and 27.5wt% of Propyl Propionate (PP), which amounts to 51.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
A first additive: structural formula 1-1;1wt%;
and a second additive: structural formula 2-1;25wt%;
nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method: the same as in example 1.
Example 10
1.1 the electrolyte comprises the following components:
the difference from the components in example 7 is that:
the structural formula of the first additive is 1-2, and the structural formula of the second additive is 2-2; the remainder were identical.
1.2 preparation method: the same as in example 7.
Example 11
1.1 the electrolyte comprises the following components:
the difference from the components in example 7 is that:
the structural formula of the first additive is 1-4, and the structural formula of the second additive is 2-3; the remainder were identical.
1.2 preparation method: the same as in example 7.
Example 12
1.1 the electrolyte comprises the following components:
the difference from the components in example 7 is that:
the structural formula of the first additive is 1-5, and the structural formula of the second additive is 2-4; the remainder were identical.
1.2 preparation method: the same as in example 7.
Example 13
1.1 the electrolyte comprises the following components:
the difference from the components in example 7 is that:
the structural formula of the first additive is 1-9, and the structural formula of the second additive is 2-5; the remainder were identical.
1.2 preparation method: the same as in example 7.
Example 14
1.1 the electrolyte comprises the following components:
the difference from the components in example 7 is that:
the structural formula of the first additive is 1-11, and the structural formula of the second additive is 2-6; the remainder were identical.
1.2 preparation method: the same as in example 7.
Preparation examples 1 to 14
1.1 preparation of lithium ion batteries
1) Preparation of positive plate
Lithium cobalt oxide (LiCoO) as a positive electrode active material 2 ) Mixing polyvinylidene fluoride (PVDF), SP (super P) and Carbon Nano Tube (CNT) according to the mass ratio of 96:2:1.5:0.5, adding N-methyl pyrrolidone (NMP), and stirring under the action of a vacuum stirrer until the mixed system becomes anode active slurry with uniform fluidity; uniformly coating anode active slurry on two surfaces of an aluminum foil; and drying the coated aluminum foil, and then rolling and slitting to obtain the required positive plate.
2) Preparation of silicon negative electrode sheet
Mixing negative electrode active material artificial graphite with silicon composite material I, sodium carboxymethylcellulose (CMC-Na), styrene-butadiene rubber, conductive carbon black (SP) and single-walled carbon nanotubes (SWCNTs) according to the mass ratio of 94.5:2.5:1.5:1:0.5, adding deionized water, and obtaining negative electrode active slurry under the action of a vacuum stirrer; uniformly coating the anode active slurry on two surfaces of a copper foil; and (3) airing the coated copper foil at room temperature, transferring to an 80 ℃ oven for drying for 10 hours, and then carrying out cold pressing and slitting to obtain the negative plate.
3) Laminating the prepared positive plate, the prepared negative plate and the prepared isolating film according to the sequence of the positive plate, the prepared isolating film and the prepared negative plate, and then winding to obtain the battery cell; and placing the battery cells in an outer packaging aluminum foil, respectively injecting the electrolyte prepared in the examples and the comparative examples into the outer packaging, and carrying out the procedures of vacuum packaging, standing, formation, shaping, sorting and the like to obtain different lithium ion batteries. The charge and discharge range of the battery is 3.0-4.5V.
1.2 the electrolyte comprises the following components: the electrolytes in examples 1 to 14 were used, respectively.
Preparation example 15
1.1 preparation of lithium ion batteries: the silicon negative electrode was made of silicon composite II, and the remainder was the same as in preparation example 1.
1.2 the electrolyte comprises the following components: the electrolyte in example 7 was used.
PREPARATION EXAMPLE 16
1.1 preparation of lithium ion batteries: the silicon negative electrode was made of silicon composite material III, and the remainder was the same as in preparation example 1.
1.2 the electrolyte comprises the following components: the electrolyte in example 7 was used.
Preparation example 17
1.1 preparation of lithium ion batteries: the silicon negative electrode was made of silicon composite material IV, and the remainder was the same as in preparation example 1.
1.2 the electrolyte comprises the following components: the electrolyte in example 7 was used.
Comparative example 1
1.1 the electrolyte comprises the following components:
organic solvent: 6wt% of Ethylene Carbonate (EC), 6wt% of Propylene Carbonate (PC), 12wt% of diethyl carbonate (DEC) and 38.5wt% of Propyl Propionate (PP), which amounts to 62.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
And a second additive: structural formula 2-1;15wt%;
nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method of electrolyte: the same as in example 7.
1.3 preparation of lithium ion batteries: the silicon negative electrode was made of silicon composite material I, and the remainder was the same as in preparation example 1.
Comparative example 2
1.1 the electrolyte comprises the following components:
organic solvent: 6wt% of Ethylene Carbonate (EC), 6wt% of Propylene Carbonate (PC), 12wt% of diethyl carbonate (DEC) and 52.5wt% of Propyl Propionate (PP), which amounts to 76.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
A first additive: structural formula 1-1;1wt%;
nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method: the same as in example 7.
1.3 preparation of lithium ion batteries: the silicon negative electrode was made of silicon composite material I, and the remainder was the same as in preparation example 1.
Comparative example 3
1.1 the electrolyte comprises the following components:
organic solvent: 6wt% of Ethylene Carbonate (EC), 6wt% of Propylene Carbonate (PC), 12wt% of diethyl carbonate (DEC) and 53.5wt% of Propyl Propionate (PP), which amounts to 77.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
Nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method: the same as in example 7.
1.3 preparation of lithium ion batteries: the silicon negative electrode was made of silicon composite material I, and the remainder was the same as in preparation example 1.
Comparative example 4
Organic solvent: ethylene Carbonate (EC) 5wt%, propylene Carbonate (PC) 5wt%, diethyl carbonate (DEC) 10wt%, propyl Propionate (PP) 27.5wt%, totaling 47.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
A first additive: structural formula 1-1;15%;
and a second additive: structural formula 2-1;15wt%;
nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method: the same as in example 7.
1.3 preparation of lithium ion batteries: the silicon negative electrode was made of silicon composite material I, and the remainder was the same as in preparation example 1.
Comparative example 5
Organic solvent: ethylene Carbonate (EC) 5wt%, propylene Carbonate (PC) 5wt%, diethyl carbonate (DEC) 10wt%, propyl Propionate (PP) 39.5wt%, total 59.5wt%;
electrolyte salt: lithium hexafluorophosphate (LiPF) 6 )，13wt％；
A first additive: structural formula 1-1;15%;
and a second additive: structural formula 2-1;3wt%;
nitrile compound: 3wt% of Adiponitrile (ADN), 3wt% of 1,3, 6-Hexanetrinitrile (HTCN);
sulfonic acid additives; 1, 3-Propane Sultone (PS), 3.5wt%.
1.2 preparation method: the same as in example 7.
1.3 preparation of lithium ion batteries: the silicon negative electrode was made of silicon composite material I, and the remainder was the same as in preparation example 1.
The silicon composite materials I-IV are lithium doped silicon oxygen materials, and the lithium doping amount and the silicon content in the silicon composite materials I-IV are different. Specifically, after the batteries prepared from the silicon composite materials I-IV are subjected to formation, the lithium content of the negative electrode and the silicon content of the negative electrode are measured and recorded in table 1. The conditions of the formation are as follows: charging at 70deg.C under high temperature and high pressure of 600kgf for 30min at 0.1C for 30min at 0.5C and 45min at 0.7C.
Among them, the lithium content and the silicon content of the anode material were tested by ICP elemental measurement. The types and amounts of the first additive and the second additive, and the lithium content and the silicon content in the negative electrode material in the above preparation examples are shown in table 1.
TABLE 1
Performance testing
The prepared lithium ion battery is respectively subjected to 45 ℃ cycle performance test, high-temperature storage test and furnace temperature safety performance test, and the test results are shown in table 2.
(1) 45 ℃ cycle performance test
The prepared battery is subjected to charge-discharge circulation for 1000 weeks in a charge-discharge cut-off voltage range according to a multiplying power of 1C at 45 ℃, the discharge capacity of the 1 st week is tested to be x1 mAh, and the discharge capacity of the N th circle is tested to be y1 mAh; the capacity at week N divided by the capacity at week 1 gives the cyclic capacity retention rate at week N r1=y1/x 1.
(2) 85 ℃ storage Performance test
Firstly, standing the battery with the chemical components for 10min, then standing for 10min at 0.2C and 3V, then fully charging at 0.5C, stopping at 0.05C, and standing for 10min. And testing the voltage, the internal resistance and the thickness of the full-charge state at the temperature of 25+/-5 ℃, placing the full-charge state in an oven at the temperature of 85 ℃ for 8 hours, taking out the voltage, the internal resistance and the thickness of the thermal state battery, and performing capacity retention and recovery tests.
(3) Furnace temperature safety performance test
Charging the battery cell with the capacity of 0.5C to the upper limit, cutting the voltage to 0.05C at constant voltage, placing the fully charged sample in a thermal shock test box at the temperature of 25+/-5 ℃, then raising the temperature to 130+/-2 ℃ at the speed of 15+/-2 ℃/min, keeping the temperature for 42min, and then finishing the test, and observing whether the battery is on fire or explosion, if not, the safety performance is expressed as safety by passing; if only fires, the fire is shown as "fire" if only explosions are generated, the fail is shown as "fail", if both fires and explosions are generated, the safety performance is shown as "fail", and all fail tests are used.
The lithium ion batteries obtained in the examples and the comparative examples were respectively subjected to 45 ℃ cycle performance test, 85 ℃ storage performance test and 130 ℃ safety heat test, and the test results are as follows:
TABLE 2
TABLE 3 Table 3
From the above experimental data, it is evident that the first additive and the second additive have an improving effect on high temperature circulation and high temperature storage and 130 ℃ furnace temperature, wherein the optimum amount of the first additive is 1% wt and the optimum amount of the second additive is 15% wt. By comparing preparation example 7 with preparation examples 15, 16 and 17, even if the same addition amount of the first additive and the second additive is selected, the silicon-lithium content ratio in the negative electrode material affects various performances of the battery, and when the silicon-lithium content ratio is out of the range defined by the present invention, the performances such as high temperature cycle and high temperature storage of the battery are degraded.
Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. The terms "first," "second," and the like, as used herein, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", etc. are used merely to indicate a relative positional relationship, which changes accordingly when the absolute position of the object to be described changes.
While the foregoing is directed to the preferred embodiments of the present invention, it will be appreciated by those skilled in the art that various modifications and adaptations can be made without departing from the principles of the present invention, and such modifications and adaptations are intended to be comprehended within the scope of the present invention.
Claims (10)
1. An electrolyte, characterized in that the electrolyte comprises:
an electrolyte salt, a solvent, a first additive, and a second additive;
the structural formula of the first additive is shown as formula (1):
x is independently selected from any one of O atom, S atom, -NH-, -PH-or-BH-; n is any natural number from 0 to 6; r is R 1 Each independently selected from the group consisting of alkyl, alkene, alkyne and aromatic hydrocarbon, or any one of the alkyl, alkene, alkyne and aromatic hydrocarbon substituted by halogen;
the structural formula of the second additive is shown as formula (2):
R 2 is a null bond or-CH 2 -, said R 2 R is represented by a null bond 3 、R 4 The two are connected through a single bond; r is R 3 、R 4 Each independently selected from at least one of halogen, alkyl, and alkyl substituted with halogen.
2. The electrolyte of claim 1, wherein the first additive is added in an amount of 0.1wt% to 10.0wt% of the total mass of the electrolyte.
3. The electrolyte of claim 1, wherein the second additive is added in an amount of 5.0wt% to 25.0wt% of the total mass of the electrolyte.
4. The electrolyte of claim 1, wherein the first additive comprises any one of structural formulas 1-1 to 1-12:
5. the electrolyte of claim 1, wherein the second additive comprises any one of structural formulas 2-1 to 2-6:
6. the electrolyte of claim 1, wherein the solvent comprises:
carbonates and/or carboxylates;
the carbonic ester comprises at least one of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate and methyl ethyl carbonate;
the carboxylic acid ester comprises at least one of propyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl acetate, isopentyl acetate, propyl propionate, ethyl propionate, methyl butyrate and ethyl n-butyrate.
7. The electrolyte of claim 1, wherein the electrolyte further comprises: sulfonic acid additives; the sulfonic acid additive comprises at least one of 1, 3-propane sultone, 1-propylene-1, 3-sultone, 5-methyl oxathiapentane 2, 2-dioxide, 1, 3-propylene sultone, 2, 4-butane sultone and 1, 4-butane sultone; and/or
The electrolyte also comprises: nitrile compounds; the nitrile compound comprises at least one of adiponitrile, succinonitrile and 1,3, 6-hexanetrinitrile.
8. A battery, comprising:
the electrolyte according to any one of claims 1 to 7;
a positive electrode sheet containing a positive electrode active material;
a negative electrode sheet containing a negative electrode active material;
and a separation film.
9. The battery according to claim 8, wherein the anode active material includes a silicon composite material and a carbon-based anode material.
10. The battery according to claim 9, wherein the percentage of silicon element in the negative electrode material is a% of the total mass of the negative electrode material, the percentage of the first additive added is B% of the total mass of the electrolyte, and the percentage of the second additive added is C%;
wherein, the value range of A is 1-25, the value range of B is 0.1-10, and the value range of C is 5-25;
A. b, C satisfy the following relationship:
0.12≤(B+C/10)/A≤3。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310742514.3A CN116632350A (en) | 2023-06-21 | 2023-06-21 | Electrolyte and battery comprising same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310742514.3A CN116632350A (en) | 2023-06-21 | 2023-06-21 | Electrolyte and battery comprising same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116632350A true CN116632350A (en) | 2023-08-22 |
Family
ID=87602650
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310742514.3A Pending CN116632350A (en) | 2023-06-21 | 2023-06-21 | Electrolyte and battery comprising same |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116632350A (en) |
-
2023
- 2023-06-21 CN CN202310742514.3A patent/CN116632350A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109728340B (en) | Lithium ion battery | |
| CN113839093A (en) | Non-aqueous electrolyte of lithium ion battery and application thereof | |
| CN111640985A (en) | Non-aqueous electrolyte and high-voltage lithium ion battery containing same | |
| CN108987802B (en) | Non-aqueous electrolyte for high-voltage lithium ion battery | |
| CN111200162A (en) | Lithium ion battery electrolyte and preparation method thereof | |
| CN109390629B (en) | Electrolyte and battery | |
| WO2022141283A1 (en) | Electrolyte, electrochemical device, and electronic device | |
| WO2024082979A1 (en) | Electrolyte and battery comprising electrolyte | |
| CN114883648B (en) | Non-aqueous electrolyte of lithium ion battery and lithium ion battery | |
| CN110808413A (en) | Non-aqueous electrolyte of lithium ion battery and lithium ion battery using same | |
| CN109119631B (en) | Secondary battery | |
| CN115441057A (en) | Electrolyte and battery comprising same | |
| CN115295881A (en) | Electrolyte additive, electrolyte and secondary battery | |
| CN115312861A (en) | Electrolyte comprises battery of the electrolyte | |
| CN110970660A (en) | Non-aqueous electrolyte and lithium ion battery | |
| CN114899476A (en) | Electrolyte and battery comprising same | |
| CN116632350A (en) | Electrolyte and battery comprising same | |
| CN114024029B (en) | Nonaqueous electrolyte and battery comprising same | |
| CN114243109B (en) | Electrolyte and battery comprising same | |
| CN116666758A (en) | Electrolyte and battery comprising same | |
| CN116365030A (en) | Electrolyte and battery comprising same | |
| CN116344942A (en) | Electrolyte and battery | |
| CN117673467A (en) | Electrolyte and battery comprising same | |
| CN116387618A (en) | Electrolyte and battery | |
| CN116344940A (en) | Electrolyte and battery comprising same |
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 |