CN117936899A - Electrolyte, additive thereof and lithium battery - Google Patents
Electrolyte, additive thereof and lithium battery Download PDFInfo
- Publication number
- CN117936899A CN117936899A CN202410083779.1A CN202410083779A CN117936899A CN 117936899 A CN117936899 A CN 117936899A CN 202410083779 A CN202410083779 A CN 202410083779A CN 117936899 A CN117936899 A CN 117936899A
- Authority
- CN
- China
- Prior art keywords
- electrolyte
- lithium
- carbonate
- additive
- total mass
- 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 104
- 229910052744 lithium Inorganic materials 0.000 title claims abstract description 82
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims abstract description 81
- 239000000654 additive Substances 0.000 title claims abstract description 55
- 230000000996 additive effect Effects 0.000 title claims abstract description 53
- 150000001875 compounds Chemical class 0.000 claims abstract description 65
- 229910003002 lithium salt Inorganic materials 0.000 claims abstract description 21
- 159000000002 lithium salts Chemical class 0.000 claims abstract description 21
- 239000002904 solvent Substances 0.000 claims abstract description 17
- VAYTZRYEBVHVLE-UHFFFAOYSA-N 1,3-dioxol-2-one Chemical compound O=C1OC=CO1 VAYTZRYEBVHVLE-UHFFFAOYSA-N 0.000 claims description 56
- OIFBSDVPJOWBCH-UHFFFAOYSA-N Diethyl carbonate Chemical compound CCOC(=O)OCC OIFBSDVPJOWBCH-UHFFFAOYSA-N 0.000 claims description 36
- KMTRUDSVKNLOMY-UHFFFAOYSA-N Ethylene carbonate Chemical compound O=C1OCCO1 KMTRUDSVKNLOMY-UHFFFAOYSA-N 0.000 claims description 36
- JBTWLSYIZRCDFO-UHFFFAOYSA-N ethyl methyl carbonate Chemical compound CCOC(=O)OC JBTWLSYIZRCDFO-UHFFFAOYSA-N 0.000 claims description 36
- VEWLDLAARDMXSB-UHFFFAOYSA-N ethenyl sulfate;hydron Chemical compound OS(=O)(=O)OC=C VEWLDLAARDMXSB-UHFFFAOYSA-N 0.000 claims description 28
- -1 lithium hexafluorophosphate Chemical compound 0.000 claims description 26
- FSSPGSAQUIYDCN-UHFFFAOYSA-N 1,3-Propane sultone Chemical compound O=S1(=O)CCCO1 FSSPGSAQUIYDCN-UHFFFAOYSA-N 0.000 claims description 24
- BTBUEUYNUDRHOZ-UHFFFAOYSA-N Borate Chemical compound [O-]B([O-])[O-] BTBUEUYNUDRHOZ-UHFFFAOYSA-N 0.000 claims description 18
- RUOJZAUFBMNUDX-UHFFFAOYSA-N propylene carbonate Chemical compound CC1COC(=O)O1 RUOJZAUFBMNUDX-UHFFFAOYSA-N 0.000 claims description 18
- 229910052736 halogen Inorganic materials 0.000 claims description 13
- 150000002367 halogens Chemical class 0.000 claims description 13
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 claims description 10
- 229910052731 fluorine Inorganic materials 0.000 claims description 10
- 239000011737 fluorine Substances 0.000 claims description 10
- 125000003545 alkoxy group Chemical group 0.000 claims description 9
- SBLRHMKNNHXPHG-UHFFFAOYSA-N 4-fluoro-1,3-dioxolan-2-one Chemical compound FC1COC(=O)O1 SBLRHMKNNHXPHG-UHFFFAOYSA-N 0.000 claims description 8
- IGILRSKEFZLPKG-UHFFFAOYSA-M lithium;difluorophosphinate Chemical compound [Li+].[O-]P(F)(F)=O IGILRSKEFZLPKG-UHFFFAOYSA-M 0.000 claims description 7
- IEJIGPNLZYLLBP-UHFFFAOYSA-N dimethyl carbonate Chemical compound COC(=O)OC IEJIGPNLZYLLBP-UHFFFAOYSA-N 0.000 claims description 6
- 125000000304 alkynyl group Chemical group 0.000 claims description 5
- 125000004432 carbon atom Chemical group C* 0.000 claims description 5
- 125000006527 (C1-C5) alkyl group Chemical group 0.000 claims description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 4
- 125000003342 alkenyl group Chemical group 0.000 claims description 4
- 125000000217 alkyl group Chemical group 0.000 claims description 4
- 125000000262 haloalkenyl group Chemical group 0.000 claims description 4
- 125000004438 haloalkoxy group Chemical group 0.000 claims description 4
- 125000001188 haloalkyl group Chemical group 0.000 claims description 4
- 229910052739 hydrogen Inorganic materials 0.000 claims description 4
- 239000001257 hydrogen Substances 0.000 claims description 4
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims description 3
- 229910052801 chlorine Inorganic materials 0.000 claims description 3
- 239000000460 chlorine Substances 0.000 claims description 3
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 claims description 2
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 claims description 2
- 229910052794 bromium Inorganic materials 0.000 claims description 2
- SYRDSFGUUQPYOB-UHFFFAOYSA-N [Li+].[Li+].[Li+].[O-]B([O-])[O-].FC(=O)C(F)=O Chemical compound [Li+].[Li+].[Li+].[O-]B([O-])[O-].FC(=O)C(F)=O SYRDSFGUUQPYOB-UHFFFAOYSA-N 0.000 claims 1
- ZJPPTKRSFKBZMD-UHFFFAOYSA-N [Li].FS(=N)F Chemical compound [Li].FS(=N)F ZJPPTKRSFKBZMD-UHFFFAOYSA-N 0.000 claims 1
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 38
- DVATZODUVBMYHN-UHFFFAOYSA-K lithium;iron(2+);manganese(2+);phosphate Chemical compound [Li+].[Mn+2].[Fe+2].[O-]P([O-])([O-])=O DVATZODUVBMYHN-UHFFFAOYSA-K 0.000 description 19
- 238000000034 method Methods 0.000 description 18
- 230000000052 comparative effect Effects 0.000 description 15
- 229910013870 LiPF 6 Inorganic materials 0.000 description 14
- 230000008569 process Effects 0.000 description 14
- 229910052723 transition metal Inorganic materials 0.000 description 12
- 150000003624 transition metals Chemical class 0.000 description 12
- 230000015572 biosynthetic process Effects 0.000 description 8
- 238000004090 dissolution Methods 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 6
- ZPFAVCIQZKRBGF-UHFFFAOYSA-N 1,3,2-dioxathiolane 2,2-dioxide Chemical compound O=S1(=O)OCCO1 ZPFAVCIQZKRBGF-UHFFFAOYSA-N 0.000 description 5
- 239000006256 anode slurry Substances 0.000 description 5
- 230000002238 attenuated effect Effects 0.000 description 5
- 238000002360 preparation method Methods 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 229940126062 Compound A Drugs 0.000 description 4
- NLDMNSXOCDLTTB-UHFFFAOYSA-N Heterophylliin A Natural products O1C2COC(=O)C3=CC(O)=C(O)C(O)=C3C3=C(O)C(O)=C(O)C=C3C(=O)OC2C(OC(=O)C=2C=C(O)C(O)=C(O)C=2)C(O)C1OC(=O)C1=CC(O)=C(O)C(O)=C1 NLDMNSXOCDLTTB-UHFFFAOYSA-N 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 239000011230 binding agent Substances 0.000 description 4
- 239000006258 conductive agent Substances 0.000 description 4
- 239000011267 electrode slurry Substances 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- QPJSUIGXIBEQAC-UHFFFAOYSA-N n-(2,4-dichloro-5-propan-2-yloxyphenyl)acetamide Chemical compound CC(C)OC1=CC(NC(C)=O)=C(Cl)C=C1Cl QPJSUIGXIBEQAC-UHFFFAOYSA-N 0.000 description 4
- 239000000843 powder Substances 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- 239000002000 Electrolyte additive Substances 0.000 description 3
- 239000004698 Polyethylene Substances 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 3
- 229920000573 polyethylene Polymers 0.000 description 3
- 125000002568 propynyl group Chemical group [*]C#CC([H])([H])[H] 0.000 description 3
- LVTJOONKWUXEFR-FZRMHRINSA-N protoneodioscin Natural products O(C[C@@H](CC[C@]1(O)[C@H](C)[C@@H]2[C@]3(C)[C@H]([C@H]4[C@@H]([C@]5(C)C(=CC4)C[C@@H](O[C@@H]4[C@H](O[C@H]6[C@@H](O)[C@@H](O)[C@@H](O)[C@H](C)O6)[C@@H](O)[C@H](O[C@H]6[C@@H](O)[C@@H](O)[C@@H](O)[C@H](C)O6)[C@H](CO)O4)CC5)CC3)C[C@@H]2O1)C)[C@H]1[C@H](O)[C@H](O)[C@H](O)[C@@H](CO)O1 LVTJOONKWUXEFR-FZRMHRINSA-N 0.000 description 3
- 238000005096 rolling process Methods 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 229910012258 LiPO Inorganic materials 0.000 description 2
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 2
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 2
- 239000002033 PVDF binder Substances 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
- 239000010405 anode material Substances 0.000 description 2
- 239000002041 carbon nanotube Substances 0.000 description 2
- 229910021393 carbon nanotube Inorganic materials 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 238000006731 degradation reaction Methods 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- 238000007599 discharging Methods 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 238000010828 elution Methods 0.000 description 2
- 239000011888 foil Substances 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 229910001416 lithium ion Inorganic materials 0.000 description 2
- 230000014759 maintenance of location Effects 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
- 239000011572 manganese Substances 0.000 description 2
- 239000012528 membrane Substances 0.000 description 2
- 125000000956 methoxy group Chemical group [H]C([H])([H])O* 0.000 description 2
- 239000012046 mixed solvent Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000011056 performance test Methods 0.000 description 2
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 2
- 230000008439 repair process Effects 0.000 description 2
- 239000007784 solid electrolyte Substances 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 1
- CPELXLSAUQHCOX-UHFFFAOYSA-N Hydrogen bromide Chemical compound Br CPELXLSAUQHCOX-UHFFFAOYSA-N 0.000 description 1
- 150000004996 alkyl benzenes Chemical class 0.000 description 1
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 125000000480 butynyl group Chemical group [*]C#CC([H])([H])C([H])([H])[H] 0.000 description 1
- 239000011203 carbon fibre reinforced carbon Substances 0.000 description 1
- 239000010406 cathode material Substances 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000007600 charging Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 238000010281 constant-current constant-voltage charging Methods 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 230000001351 cycling effect Effects 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 238000005562 fading Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 229910052740 iodine Inorganic materials 0.000 description 1
- 239000011630 iodine Substances 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 125000004115 pentoxy group Chemical group [*]OC([H])([H])C([H])([H])C([H])([H])C(C([H])([H])[H])([H])[H] 0.000 description 1
- 125000001147 pentyl group Chemical group C(CCCC)* 0.000 description 1
- 125000005981 pentynyl group Chemical group 0.000 description 1
- 239000007774 positive electrode material Substances 0.000 description 1
- 125000001436 propyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 125000000026 trimethylsilyl group Chemical group [H]C([H])([H])[Si]([*])(C([H])([H])[H])C([H])([H])[H] 0.000 description 1
Landscapes
- Secondary Cells (AREA)
Abstract
An electrolyte, an additive and a lithium battery thereof belong to the technical field of batteries. The electrolyte includes a lithium salt, an additive, and a solvent. Wherein the additive comprises a compound represented by formula (I):
Description
Technical Field
The application relates to the technical field of batteries, in particular to electrolyte, an additive thereof and a lithium battery.
Background
With the rapid development of new energy automobiles, lithium ion batteries are widely studied and applied as power sources thereof. However, the existing new energy automobile still has the problems of high cost of anode materials, short endurance mileage, long charging time, thermal runaway and the like. Therefore, in order to solve the problems of high cost of the positive electrode material and short endurance mileage of the new energy automobile, the development of the lithium ion battery with low cost and long cycle life is urgent.
Development of high voltage platform cathode materials is one of the main methods to increase battery energy density. The olivine-structured lithium iron manganese phosphate (LMFP) material has high energy density and high voltage platform, and is a novel anode material with high cost performance. However, the LMFP material inevitably undergoes elution of transition metal manganese and iron during charge and discharge cycles. The dissolution of the transition metal reduces the lithium storage capacity of the positive electrode on the one hand, and the dissolved transition metal is deposited on the surface of the negative electrode on the other hand, so that a large amount of electrolyte is decomposed, and the battery capacity is attenuated sharply.
Trace water in the electrolyte is also one of key factors affecting the cycle life of the battery, and lithium hexafluorophosphate is used as a commercially used electrolyte lithium salt, which reacts with trace water to easily generate hydrofluoric acid (HF), and the generated HF damages a solid electrolyte membrane of a negative electrode, thereby causing damage and repair of an SEI film and further causing capacity degradation of the battery.
Disclosure of Invention
In view of the above-described shortcomings, the present application provides an electrolyte, an additive thereof, and a lithium battery to partially or totally improve the problems of capacity fade of the battery in the related art.
The application is realized in the following way:
In a first aspect, examples of the present application provide an additive for an electrolyte comprising a compound of formula (I):
In formula (I), R1 and R2 are each independently selected from C1-C5 alkyl, C1-C5 alkoxy or alkynyl of at least 3 carbon atoms; r3, R4, R5, R6 and R7 are each independently selected from any one of alkyl, alkoxy, alkenyl, haloalkyl, haloalkoxy, haloalkenyl, hydroxy, carboxy, ether oxy, halogen or hydrogen.
In the implementation process, the compound shown in the formula (I) is added into the electrolyte, and the lithium battery prepared by using the electrolyte can participate in the formation of a positive electrode interface film (CEI film) under high voltage in the use process, so that the dissolution of positive electrode transition metal is inhibited, and meanwhile, the compound in the additive can react with hydrofluoric acid, so that the damage degree of the hydrofluoric acid to a negative electrode interface film (SEI film) can be reduced, and the cycle capacity of the lithium manganese iron phosphate battery can be improved.
With reference to the first aspect, in a possible embodiment, the halogen is selected from at least one of fluorine, chlorine or bromine.
With reference to the first aspect, in a possible embodiment, at least one halogen of R3, R4, R5, R6 and R7.
With reference to the first aspect, in one possible embodiment, R3, R4, R5, R6 and R7 are all selected from halogen.
Optionally, R3, R4, R5, R6 and R7 are all selected from fluorine, and the structural formula of the compound is:
In the implementation process, at least one of R3, R4, R5, R6 and R7 is selected from halogen such as fluorine, so that the compound can participate in the formation of an anode interface film under high voltage to inhibit the dissolution of anode transition metal, and meanwhile, the compound in the additive can react with hydrofluoric acid to reduce the damage degree of the hydrofluoric acid to the anode interface film, thereby improving the circulation capacity of the lithium manganese iron phosphate battery.
With reference to the first aspect, in one possible embodiment, the structural formula of the compound includes:
In the implementation process, the compound with the structural formula is used as an additive of the electrolyte, can participate in the formation of an anode interface film under high voltage, inhibits the dissolution of transition metal at the anode, can react with hydrofluoric acid, reduces the damage degree of the hydrofluoric acid to the cathode interface film, and further can improve the circulation capacity of the lithium manganese iron phosphate battery.
With reference to the first aspect, in one possible embodiment, the additive further comprises at least one of vinylene carbonate, vinyl sulfate, 1, 3-propane sultone, propenyl-1, 3-sultone, fluoroethylene carbonate.
In the implementation process, the compound shown in the formula (I) is matched with at least one of vinylene carbonate, vinyl sulfate, 1, 3-propane sultone, propenyl-1, 3-sultone or fluoroethylene carbonate, so that the problem of cycle capacity attenuation of the lithium iron manganese phosphate battery can be further improved.
With reference to the first aspect, in one possible embodiment, the additive is selected from the group consisting of a compound, vinylene carbonate and vinyl sulfate.
Optionally, the additive is selected from the group consisting of a compound, vinylene carbonate, vinyl sulfate, and 1, 3-propane sultone.
In the implementation process, the compound, the vinylene carbonate and the vinyl sulfate are matched, so that the circulation capacity of the lithium iron manganese phosphate battery can be further improved.
In a second aspect, an example of the application provides an electrolyte comprising a lithium salt, a solvent, and an additive as provided in the first aspect.
In the implementation process, the electrolyte comprises lithium salt, a solvent and the electrolyte additive provided in the first aspect, wherein a compound in the additive can participate in the formation of an anode interface film under high voltage to inhibit the dissolution of transition metal at the anode, and meanwhile, the compound in the additive can react with hydrofluoric acid to consume hydrofluoric acid, so that the damage degree of the hydrofluoric acid to the anode interface film can be reduced, and the circulation capacity of the lithium manganese iron phosphate battery can be improved.
With reference to the second aspect, in one possible embodiment, the additive comprises 0.5% -5.4% of the total mass of the electrolyte.
With reference to the second aspect, in one possible embodiment, the lithium salt comprises 10% -15% of the total mass of the electrolyte.
In the implementation process, the additive accounts for 0.5-5.4% of the total mass of the electrolyte, and the lithium salt accounts for 10-15% of the total mass of the electrolyte, so that the circulating capacity of the lithium iron manganese phosphate battery can be further improved.
With reference to the second aspect, in one possible embodiment, the lithium salt is selected from at least one of lithium hexafluorophosphate, lithium difluorosulfonimide, lithium dioxaborate, lithium difluorooxalato borate or lithium difluorophosphate.
With reference to the second aspect, in one possible embodiment, the solvent is selected from at least one of ethylene carbonate, propylene carbonate, ethylmethyl carbonate, dimethyl carbonate or diethyl carbonate.
With reference to the second aspect, in one possible embodiment, the solvent is selected from the group consisting of ethylene carbonate, propylene carbonate, ethylmethyl carbonate, dimethyl carbonate and diethyl carbonate.
Optionally, ethylene carbonate accounts for 10-15% of the total mass of the electrolyte, propylene carbonate accounts for 5-8% of the total mass of the electrolyte, methyl ethyl carbonate accounts for 30-40% of the total mass of the electrolyte, and diethyl carbonate accounts for 20-25% of the total mass of the electrolyte.
In the implementation process, the circulation capacity of the lithium iron manganese phosphate battery can be further improved by utilizing the combination of 10-15% of ethylene carbonate, 5-8% of propylene carbonate, 30-40% of methyl ethyl carbonate and 20-25% of diethyl carbonate.
With reference to the second aspect, in one possible embodiment, the additive further comprises at least one of vinylene carbonate, vinyl sulfate, 1, 3-propane sultone, propenyl-1, 3-sultone, fluoroethylene carbonate.
In the implementation process, the compound shown in the formula (I) is matched with at least one of vinylene carbonate, vinyl sulfate, 1, 3-propane sultone, propenyl-1, 3-sultone or fluoroethylene carbonate, so that the cycle capacity of the lithium iron manganese phosphate battery can be further improved.
With reference to the second aspect, in one possible embodiment, the additive is selected from the group consisting of vinylene carbonate, vinyl sulfate, 1, 3-propane sultone, propenyl-1, 3-sultone and compounds.
Optionally, the vinylene carbonate accounts for 0.5-2% of the total mass of the electrolyte, the vinyl sulfate accounts for 0.5-1.2% of the total mass of the electrolyte, the 1, 3-propane sultone accounts for 0.2-1.2% of the total mass of the electrolyte, the propenyl-1, 3-sultone accounts for 0.2-0.5% of the total mass of the electrolyte, and the compound accounts for 0.5-3% of the total mass of the electrolyte.
Optionally, the compound accounts for 0.5-1.5% of the total mass of the electrolyte.
In the implementation process, the circulation capacity of the lithium iron manganese phosphate battery can be further improved by utilizing the combination of 0.5-2% of vinylene carbonate, 0.5-1.2% of vinyl sulfate, 0.2-1.2% of 1, 3-propane sultone, 0.2-0.5% of propenyl-1, 3-sultone and 0.5-3% of compounds.
In a third aspect, the present examples provide a lithium battery comprising the electrolyte provided in the second aspect.
In the implementation process, the electrolyte provided by the example of the application is used for preparing the lithium battery, the compound in the electrolyte additive can participate in the formation of the positive electrode interface film under high voltage to inhibit the dissolution of the positive electrode transition metal, and meanwhile, the compound in the additive can react with hydrofluoric acid to reduce the damage degree of the hydrofluoric acid to the negative electrode interface film, so that the circulation capacity of the lithium iron manganese phosphate battery can be improved.
Detailed Description
Embodiments of the present application will be described in detail below with reference to examples, but it will be understood by those skilled in the art that the following examples are only for illustrating the present application and should not be construed as limiting the scope of the present application. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.
The olivine-structured lithium iron manganese phosphate (LMFP) material has high energy density and a high voltage platform, and can improve the energy density of a lithium battery.
However, the LMFP material inevitably undergoes elution of transition metal manganese and iron during charge and discharge cycles. On the one hand, the lithium storage capacity of the positive electrode can be reduced by the dissolution of the transition metal, and on the other hand, the dissolved transition metal can be deposited on the surface of the negative electrode, so that a large amount of electrolyte can be decomposed, and the battery capacity can be rapidly attenuated.
In addition, trace water in the electrolyte can also affect the cycle life of a lithium battery, lithium hexafluorophosphate is a commercially used electrolyte lithium salt, hydrofluoric acid (HF) is easy to generate when the lithium hexafluorophosphate reacts with trace water, and the generated HF can damage a solid electrolyte membrane of a negative electrode, so that an SEI film is damaged and repaired, and the battery capacity is further reduced.
Therefore, the application further improves the electrolyte, thereby improving the battery capacity of the lithium battery to a certain extent and improving the problem of battery capacity attenuation.
The electrolyte provided by the application comprises lithium salt, solvent and additive.
Wherein the additive comprises a compound represented by formula (I):
In formula (I), R1 and R2 are each independently selected from C1-C5 alkyl, alkoxy or alkynyl of at least 3 carbon atoms; r3, R4, R5, R6 and R7 are each independently selected from any one of alkyl, alkoxy, alkenyl, haloalkyl, haloalkoxy, haloalkenyl, hydroxy, carboxy, ether oxy, halogen or hydrogen.
The compound shown in the formula (I) is used as an additive of the electrolyte, and contains unsaturated double bonds such as nitrogen-carbon double bonds, carbon-sulfur double bonds, carbon-carbon double bonds and silicon-carbon bonds, so that the compound can participate in the formation of an anode interface film under high voltage, further the dissolution of transition metal at the anode is inhibited, and the battery capacity and the capacity attenuation of a lithium battery are improved.
Meanwhile, the compound in the additive can react with hydrofluoric acid, so that the hydrofluoric acid generated in the electrolyte can be consumed, the damage degree of the hydrofluoric acid to the negative electrode interface film is further reduced, the circulating capacity of the lithium manganese iron phosphate battery can be further improved, and the capacity attenuation of the lithium battery is relieved.
The application is not limited to the specific type of choice of R1 and R2, and the relevant person may make the corresponding choice within the range of C1-C5 alkyl, C1-C5 alkoxy or alkynyl of at least 3 carbon atoms, as desired.
In one possible embodiment, R1 and R2 are each independently selected from any one of methyl, ethyl, propyl, butyl, or pentyl.
In one possible embodiment, R1 and R2 are each independently selected from any one of methoxy, ethoxy, propoxy, butoxy, or pentoxy.
In one possible embodiment, R1 and R2 are each independently selected from any one of propynyl, butynyl or pentynyl.
Further, in one possible embodiment, R1 and R2 may be the same.
Illustratively, R1 and R2 may each be selected from methyl.
Illustratively, R1 and R2 may each be selected from methoxy.
Illustratively, R1 and R2 may each be selected from propynyl.
Further, the application is not limited to the specific types of R3, R4, R5, R6 and R7.
In one possible embodiment, R3, R4, R5, R6 and R7 are each independently selected from any one of alkyl, alkoxy, alkenyl, haloalkyl, haloalkoxy, haloalkenyl, hydroxy, carboxy, ether oxy, halogen or hydrogen.
Further, in one possible embodiment, at least one of R3, R4, R5, R6, and R7 is selected from halogen.
Illustratively, the halogen is selected from elemental fluorine, elemental chlorine, elemental bromine, or elemental iodine.
Further, R3, R4, R5, R6 and R7 are the same.
Illustratively, R3, R4, R5, R6, and R7 may each be selected from the group consisting of elemental fluorine.
In the compounds, R3, R4, R5, R6 and R7 are each selected from fluorine, and R1 and R2 are each selected from methyl. The structural formula of the compound is as follows:
and is designated as compound a.
In the compound, R3, R4, R5, R6 and R7 are each selected from fluorine elements, and R1 and R2 may be each selected from methoxy groups. The structural formula of the compound is as follows:
And is designated compound B.
In the compounds, R3, R4, R5, R6 and R7 are each selected from fluorine elements, and R1 and R2 may each be selected from propynyl. The structural formula of the compound is as follows:
And is designated compound C.
Further, the application also provides a preparation method of the compound:
The substitution reaction is carried out by utilizing alkylbenzene and trimethylsilyl.
To further improve the battery capacity degradation problem, in one possible embodiment, the additive may further include at least one of Vinylene Carbonate (VC), vinyl sulfate (DTD), 1, 3-Propane Sultone (PS), propenyl-1, 3-sultone (PES), fluoroethylene carbonate (PEC).
The compound is matched with Vinylene Carbonate (VC), vinyl sulfate (DTD), 1, 3-Propane Sultone (PS), propenyl-1, 3-sultone (PES), fluoroethylene carbonate (PEC) and the like, so that the formation and repair of an electrode interface film can be further promoted, the impedance of a battery is reduced, the decomposition of electrolyte is inhibited, the content of hydrofluoric acid is consumed, the attenuation problem of the battery capacity is improved, and the battery capacity is improved.
In one possible embodiment, the additive is selected from the group consisting of a compound, vinylene Carbonate (VC), and vinyl sulfate (DTD).
Further, in one possible embodiment, the additive is selected from the group consisting of a compound, vinylene Carbonate (VC), vinyl sulfate (DTD), and 1, 3-Propane Sultone (PS).
Further, in one possible embodiment, the additive is selected from the group consisting of a compound, vinylene Carbonate (VC), vinyl sulfate (DTD), 1, 3-Propane Sultone (PS), and propenyl-1, 3-sultone (PES).
Further, in one possible embodiment, the additive comprises 0.5% -8% of the total mass of the electrolyte.
Further, in one possible embodiment, the additive comprises 1.9% -7.9% of the total mass of the electrolyte.
Illustratively, the additive comprises, by weight of the electrolyte, 0.5 to 2% Vinylene Carbonate (VC), 0.5 to 1.2% vinyl sulfate (DTD), 0.2 to 1.2% 1, 3-Propane Sultone (PS), 0.2 to 0.5% propenyl-1, 3-sultone (PES) and 0.5 to 3% of a compound, the balance being a lithium salt and a solvent.
Further, in one possible embodiment, the additive comprises 2.5% -5.4% of the total mass of the electrolyte.
Further, the compound accounts for 0.5 to 1.5 percent of the total mass of the electrolyte.
Illustratively, the compound comprises a range between one or any two of 0.5%, 1.0%, or 1.5% of the total mass of the electrolyte.
Further, the present application is not limited to a particular type of lithium salt, and in one possible embodiment, the lithium salt is selected from at least one of lithium hexafluorophosphate, lithium difluorosulfonimide, lithium dioxaborate, lithium difluorooxalato borate, or lithium difluorophosphate.
Illustratively, in the electrolyte, the lithium salt is selected from four of lithium hexafluorophosphate (LiPF 6), lithium bis-fluorosulfonyl imide (LiFSI), lithium difluorooxalato borate (lipfob), and lithium difluorophosphate (LiPO 2F2).
Further, in one possible embodiment, the lithium salt comprises 10% to 15% of the total mass of the electrolyte.
Illustratively, the lithium salt comprises a range between one or any two of 10%, 11%, 12%, 13%, 14% and 15% of the total mass of the electrolyte.
Illustratively, the electrolyte comprises, in weight percent, 8 to 9.5% lithium hexafluorophosphate (LiPF 6), 1 to 3% lithium difluorosulfonimide (LiFSI), 0.5 to 1.5% lithium difluorooxalato borate (lipfob), and 0.5 to 1% lithium difluorophosphate (LiPO 2F2), the balance being additives and solvents.
Further, the present application is not limited to a specific type of solvent, and in one possible embodiment, the solvent is selected from at least one of Ethylene Carbonate (EC), propylene Carbonate (PC), ethylmethyl carbonate (EMC), dimethyl carbonate (DMC), or diethyl carbonate (DEC).
Illustratively, the solvent in the electrolyte is selected from the group consisting of ethylene carbonate, propylene carbonate, ethylmethyl carbonate, dimethyl carbonate, and diethyl carbonate.
Further, in one possible embodiment, the electrolyte comprises, in weight percent, 10 to 15% Ethylene Carbonate (EC), 5 to 8% Propylene Carbonate (PC), 30 to 40% ethylmethyl carbonate (EMC) and 20 to 25% diethyl carbonate (DEC), the balance being additives and lithium salts.
Or in one possible embodiment, the electrolyte comprises, in weight percent: 8-12% of lithium hexafluorophosphate (LiPF 6), 0.5-1.5% of lithium difluorooxalato borate (LiDFOB), 20-25% of Ethylene Carbonate (EC), 1-5% of Propylene Carbonate (PC), 20-30% of methyl ethyl carbonate (EMC) and 15-25% of diethyl carbonate (DEC); 0.5 to 1 percent of Vinylene Carbonate (VC) and 0.5 to 2 percent of compound A.
Or in one possible embodiment, the electrolyte comprises, in weight percent: 8-12% of lithium hexafluorophosphate (LiPF 6), 0.5-1.5% of lithium difluorooxalato borate (LiDFOB), 20-25% of Ethylene Carbonate (EC), 1-5% of Propylene Carbonate (PC), 20-30% of methyl ethyl carbonate (EMC) and 15-25% of diethyl carbonate (DEC); 0.5 to 1 percent of Vinylene Carbonate (VC) and 0.5 to 2 percent of compound B.
Or in one possible embodiment, the electrolyte comprises, in weight percent: 8-12% of lithium hexafluorophosphate (LiPF 6), 0.5-1.5% of lithium difluorooxalato borate (LiDFOB), 20-25% of Ethylene Carbonate (EC), 1-5% of Propylene Carbonate (PC), 20-30% of methyl ethyl carbonate (EMC) and 15-25% of diethyl carbonate (DEC); 0.5 to 1 percent of Vinylene Carbonate (VC) and 0.5 to 2 percent of compound C.
Further, the application also provides a preparation method of the electrolyte.
The preparation method of the electrolyte comprises the following steps:
S1, mixing weighed solvents to obtain a mixed solvent;
S2, adding the weighed lithium salt and the additive into the mixed solvent prepared in the step S1;
And S3, fully and uniformly stirring the obtained solution to obtain the colorless and transparent electrolyte.
Further, the application also provides a lithium battery. The lithium battery includes the electrolyte provided by the example of the application.
Further, the lithium battery also comprises a positive pole piece, a negative pole piece and a diaphragm.
Further, the positive electrode sheet can be prepared by the following method:
And uniformly dispersing the anode powder lithium iron manganese phosphate, the conductive agent carbon nano tube and super P as well as the binder PVDF into the solvent NMP according to a certain mass ratio. The solid content of the anode slurry after uniform dispersion is controlled to be 60 percent, and the anode slurry is uniformly coated on an aluminum foil, dried, rolled and die-cut for later use.
Further, the negative electrode plate can be prepared by the following method:
Uniformly dispersing negative electrode powder graphite, a conductive agent super P, a binder CMC and SBR in deionized water according to a certain mass ratio. And (3) fully and uniformly stirring, controlling the solid content of the negative electrode slurry to be 50%, discharging, uniformly coating the negative electrode slurry on a negative electrode current collector, and drying, rolling and die-cutting for later use.
Further, the separator may be a composite separator such as a composite separator formed of a 9 μm polyethylene-based film and a double-sided alumina ceramic separator.
The electrolyte of the present application is described in further detail below with reference to examples.
Example 1
Example 1 provides an electrolyte comprising, in weight percent: 12.8% of lithium hexafluorophosphate (LiPF 6), 1.5% of lithium difluorooxalato borate (LiDFOB), 25% of Ethylene Carbonate (EC), 43.2% of methyl ethyl carbonate (EMC), 15% of diethyl carbonate (DEC) and 1.5% of Vinylene Carbonate (VC); compound a1.0%.
Example 2
Example 2 provides an electrolyte comprising, in weight percent: 12.8% of lithium hexafluorophosphate (LiPF 6), 1.5% of lithium difluorooxalato borate (LiDFOB), 25% of Ethylene Carbonate (EC), 42% of methyl ethyl carbonate (EMC), 15% of diethyl carbonate (DEC) and 1.5% of Vinylene Carbonate (VC); vinyl sulfate (DTD) 1.2%, compound a1.0%.
Example 3
Example 3 provides an electrolyte comprising, in weight percent: 12.8% of lithium hexafluorophosphate (LiPF 6), 1.5% of lithium difluorooxalato borate (LiDFOB), 25% of Ethylene Carbonate (EC), 40.8% of ethylmethyl carbonate (EMC), 15% of diethyl carbonate (DEC), 1.5% of Vinylene Carbonate (VC), 1.2% of ethylene sulfate (DTD), 1.2% of 1, 3-Propane Sultone (PS) and 1.0% of compound A.
Example 4
Example 4 provides an electrolyte comprising, in weight percent: 12.8% of lithium hexafluorophosphate (LiPF 6), 1.5% of lithium difluorooxalato borate (LiDFOB), 25% of Ethylene Carbonate (EC), 41.3% of ethylmethyl carbonate (EMC), 15% of diethyl carbonate (DEC), 1.5% of Vinylene Carbonate (VC), 1.2% of ethylene sulfate (DTD), 1.2% of 1, 3-Propane Sultone (PS) and 0.5% of compound A.
Example 5
Example 5 provides an electrolyte comprising, in weight percent: 12.8% of lithium hexafluorophosphate (LiPF 6), 1.5% of lithium difluorooxalato borate (LiDFOB), 25% of Ethylene Carbonate (EC), 40.3% of ethylmethyl carbonate (EMC), 15% of diethyl carbonate (DEC), 1.5% of Vinylene Carbonate (VC), 1.2% of ethylene sulfate (DTD), 1.2% of 1, 3-Propane Sultone (PS) and 1.5% of compound A.
Example 6
Example 6 provides an electrolyte comprising, in weight percent: 12.8% of lithium hexafluorophosphate (LiPF 6), 1.5% of lithium difluorooxalato borate (LiDFOB), 25% of Ethylene Carbonate (EC), 40.3% of ethylmethyl carbonate (EMC), 15% of diethyl carbonate (DEC), 2% of Vinylene Carbonate (VC), 1.2% of vinyl sulfate (DTD), 1.2% of 1, 3-Propane Sultone (PS) and 1.0% of compound B.
Example 7
Example 7 provides an electrolyte comprising, in weight percent: 12.8% of lithium hexafluorophosphate (LiPF 6), 1.5% of lithium difluorooxalato borate (LiDFOB), 25% of Ethylene Carbonate (EC), 40.8% of ethylmethyl carbonate (EMC), 15% of diethyl carbonate (DEC), 1.5% of Vinylene Carbonate (VC), 1.2% of ethylene sulfate (DTD), 1.2% of 1, 3-Propane Sultone (PS) and 1.0% of compound C.
Comparative example 1
Comparative example 1 provides an electrolyte comprising, in weight percent: 12.8% of lithium hexafluorophosphate (LiPF 6), 1.5% of lithium difluorooxalato borate (LiDFOB), 25% of Ethylene Carbonate (EC), 44.2% of ethylmethyl carbonate (EMC), 15% of diethyl carbonate (DEC) and 1.5% of Vinylene Carbonate (VC). Comparative example 1 contains no compound additive.
Comparative example 2
Comparative example 2 provides an electrolyte comprising, in weight percent: 12.8% of lithium hexafluorophosphate (LiPF 6), 1.5% of lithium difluorooxalato borate (LiDFOB), 25% of Ethylene Carbonate (EC), 43% of ethylmethyl carbonate (EMC), 15% of diethyl carbonate (DEC), 1.5% of Vinylene Carbonate (VC) and 1.2% of ethylene sulfate (DTD). Comparative example 2 contains no compound additive.
Test case
Lithium iron manganese phosphate (LMFP) batteries were prepared using the electrolytes provided in examples 1 to 7 and comparative examples 1 to 2, respectively.
The preparation method comprises the following steps:
Firstly, preparing an LMFP positive pole piece;
Uniformly dispersing anode powder such as lithium iron manganese phosphate, a conductive agent carbon nano tube, super P and a binder PVDF in a solvent NMP according to a certain mass ratio. And controlling the solid content of the anode slurry after uniform dispersion to be 60%, uniformly coating the anode slurry on an aluminum foil, and drying, rolling and die-cutting the anode slurry for later use.
Secondly, preparing a negative electrode plate;
uniformly dispersing negative electrode powder such as graphite, a conductive agent super P, a binder CMC and SBR in deionized water according to a certain mass ratio. And (3) fully and uniformly stirring, controlling the solid content of the negative electrode slurry to be 50%, discharging, uniformly coating the negative electrode slurry on a negative electrode current collector, and drying, rolling and die-cutting for later use.
Thirdly, preparing a diaphragm;
A ceramic separator consisting of a Polyethylene (PE) base film 9 μm plus double-sided alumina (Al 2O3) was used.
Fourth, preparation of the battery:
and manufacturing the battery pole group with 10 positive pole pieces and 11 negative pole pieces by using the positive pole pieces, the diaphragms and the negative pole pieces through a lamination process. After the electrode groups are assembled, the electrolyte provided in the examples 1-7 and the electrolyte provided in the comparative examples 1-2 are respectively injected, and the finished battery is obtained after the processes of standing, formation and capacity division.
Cycling performance tests were performed on lithium iron manganese phosphate batteries prepared using the electrolytes provided in examples 1 to 7 and comparative examples 1 to 2, respectively.
The method for testing the cycle performance comprises the following steps:
the lithium iron manganese phosphate batteries prepared in examples 1 to 7 and comparative examples 1 to 2 were subjected to constant-current constant-voltage charging at a rate of 1C, with an upper limit voltage of 4.2V and a cut-off current of 0.05C. And carrying out constant-current discharge on the battery at the rate of 1C, wherein the lower limit voltage of discharge is 2.5V.
The above charge and discharge steps were repeated until the capacity of the battery decayed to 80% of the initial capacity, and the number of cycles of the battery was recorded.
The test results are shown in Table 1.
Table 1 cyclic performance test table
| 25 ℃ Cycle @80% capacity retention | 45 ℃ Cycle @80% capacity retention | |
| Example 1 | 1000 | 850 |
| Example 2 | 3200 | 2800 |
| Example 3 | 3500 | 2900 |
| Example 4 | 1800 | 1200 |
| Example 5 | 2000 | 1500 |
| Example 6 | 3800 | 3500 |
| Example 7 | 4000 | 3700 |
| Comparative example 1 | 800 | 600 |
| Comparative example 2 | 850 | 700 |
Analysis of results:
In Table 1, in combination with examples 1 to 7 and comparative examples 1 to 2, it can be seen that the number of cycles is not less than 1000 cycles, higher than those of comparative examples 1 and 2 when the capacity of the lithium battery is reduced to 80% of the initial capacity at 25℃in the lithium battery obtained by preparing the electrolyte containing the compound additive provided in the examples of the present application. The lithium battery prepared from the electrolyte containing the compound additive provided by the embodiment of the application has a cycle number of not less than 850 circles and higher than 600-700 circles of comparative examples 1 and 2 when the capacity of the lithium battery is reduced to 80% of the initial capacity after being cycled at 45 ℃. By using the compound provided by the example of the application as an electrolyte additive, the capacity fading problem of a lithium battery can be relieved, and the cyclicity of the lithium battery can be improved.
In combination with examples 1 and 2, the lithium battery obtained by using the electrolyte provided in example 2 of the present application has a cycle number of up to 3200 cycles at 25 ℃ when the capacity of the lithium battery is attenuated to 80% of the initial capacity, which is higher than 1000 cycles of example 1; the number of cycles at 45 ℃ until the capacity of the lithium battery decays to 80% of the initial capacity is as high as 2800 cycles, higher than 850 cycles of example 1. By way of illustration, the present example can further alleviate the capacity fade problem of a lithium battery and can further improve the recyclability of the lithium battery by using the combination of Vinylene Carbonate (VC), vinyl sulfate (DTD) and compound a.
In combination with example 2 and example 3, the lithium battery obtained by using the electrolyte provided in example 3 of the present application has a cycle number of up to 3500 cycles, higher than 3200 cycles of example 2, when the capacity of the lithium battery is reduced to 80% of the initial capacity at 25 ℃; the number of cycles at 45 ℃ until the capacity of the lithium battery decays to 80% of the initial capacity is as high as 2900 turns, which is higher than 2800 turns of example 2. The present application is exemplified by the fact that the capacity fade problem of a lithium battery can be further improved and the cyclicity of the lithium battery can be further improved by compounding Vinylene Carbonate (VC), vinyl sulfate (DTD), 1, 3-Propane Sultone (PS) and compound a.
In combination with examples 2, 3 and 4, it can be seen that as the amount of compound a added increases from 0.5% to 1.5%, the number of cycles of the lithium battery increases and decreases, and when the amount of compound a added is 1%, the number of cycles of the lithium battery at 25 ℃ until the capacity of the lithium battery decays to 80% of the initial capacity is as high as 3500 cycles, and the number of cycles at 45 ℃ until the capacity of the lithium battery decays to 80% of the initial capacity is as high as 2900 cycles.
In combination with examples 3,6 and 7, it can be seen that, in the compound provided in example 6, R1 and R2 are both selected from alkoxy groups, the cycle number of the lithium battery when the lithium battery is cycled at 25 ℃ until the capacity of the lithium battery is attenuated to 80% of the initial capacity is 3800, and the cycle number of the lithium battery when the lithium battery is cycled at 45 ℃ until the capacity of the lithium battery is attenuated to 80% of the initial capacity is 3500, so that the capacity attenuation problem of the lithium battery can be further improved, and the cyclicity of the lithium battery can be further improved; in the compound provided in example 7, R1 and R2 are both selected from alkynyl groups of three carbon atoms, the cycle number of the lithium battery at 25 ℃ until the capacity of the lithium battery is reduced to 80% of the initial capacity is up to 4000 cycles, and the cycle number of the lithium battery at 45 ℃ until the capacity of the lithium battery is reduced to 80% of the initial capacity is up to 3700 cycles, so that the capacity reduction problem of the lithium battery can be further improved, and the cycle performance of the lithium battery can be further improved.
The above description is only of the preferred embodiments of the present application and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims (17)
1. An additive for an electrolyte, characterized in that the additive comprises a compound represented by formula (I):
In formula (I), R1 and R2 are each independently selected from C1-C5 alkyl, C1-C5 alkoxy or alkynyl of at least 3 carbon atoms; r3, R4, R5, R6 and R7 are each independently selected from any one of alkyl, alkoxy, alkenyl, haloalkyl, haloalkoxy, haloalkenyl, hydroxy, carboxy, ether oxy, halogen or hydrogen.
2. The additive of claim 1, wherein the halogen is selected from at least one of fluorine, chlorine or bromine.
3. An additive according to claim 1, wherein at least one of R3, R4, R5, R6 and R7 is halogen.
4. An additive according to claim 1, wherein R3, R4, R5, R6 and R7 are all selected from the halogens;
optionally, R3, R4, R5, R6 and R7 are all selected from fluorine elements, and the structural formula of the compound is:
5. The additive of claim 4 wherein the structural formula of the compound comprises:
6. An additive according to any one of claims 1 to 5, further comprising at least one of vinylene carbonate, vinyl sulfate, 1, 3-propane sultone, propenyl-1, 3-sultone and fluoroethylene carbonate.
7. An additive according to claim 6, wherein the additive is selected from the group consisting of the compound, the vinylene carbonate and the vinyl sulfate;
optionally, the additive is selected from the group consisting of the compound, the vinylene carbonate, the vinyl sulfate, and the 1, 3-propane sultone.
8. An electrolyte comprising a lithium salt, a solvent and the additive of any one of claims 1-7.
9. The electrolyte of claim 8 wherein the additive comprises 0.5% to 5.4% of the total mass of the electrolyte.
10. The electrolyte of claim 8 wherein the lithium salt comprises 10% -15% of the total mass of the electrolyte.
11. The electrolyte of claim 10, wherein the lithium salt is selected from at least one of lithium hexafluorophosphate, lithium difluorosulfonimide, lithium dioxaborate, lithium difluorooxalato borate, or lithium difluorophosphate.
12. The electrolyte of claim 11 wherein the lithium salt is selected from the group consisting of lithium hexafluorophosphate, lithium difluorosulfonimide, lithium difluorooxalato borate, and lithium difluorophosphate;
the lithium hexafluorophosphate accounts for 8-9.5% of the total mass of the electrolyte, the lithium difluorosulfimide accounts for 1-3% of the total mass of the electrolyte, the lithium difluorooxalate borate accounts for 0.5-1.5% of the total mass of the electrolyte, and the lithium difluorophosphate accounts for 0.5-1% of the total mass of the electrolyte.
13. The electrolyte of claim 8, wherein the solvent is selected from at least one of ethylene carbonate, propylene carbonate, ethylmethyl carbonate, dimethyl carbonate, or diethyl carbonate.
14. The electrolyte of claim 13 wherein the solvent is selected from the group consisting of the ethylene carbonate, the propylene carbonate, the methyl ethyl carbonate, the dimethyl carbonate, and the diethyl carbonate;
Optionally, the ethylene carbonate accounts for 10-15% of the total mass of the electrolyte, the propylene carbonate accounts for 5-8% of the total mass of the electrolyte, the methyl ethyl carbonate accounts for 30-40% of the total mass of the electrolyte, and the diethyl carbonate accounts for 20-25% of the total mass of the electrolyte.
15. The electrolyte of claim 8 wherein the additive further comprises at least one of vinylene carbonate, vinyl sulfate, 1, 3-propane sultone, propenyl-1, 3-sultone, fluoroethylene carbonate.
16. The electrolyte of claim 15 wherein the additive is selected from the group consisting of the vinylene carbonate, the vinyl sulfate, the 1, 3-propane sultone, the propenyl-1, 3-sultone, and the compound;
Optionally, the vinylene carbonate accounts for 0.5-2% of the total mass of the electrolyte, the vinyl sulfate accounts for 0.5-1.2% of the total mass of the electrolyte, the 1, 3-propane sultone accounts for 0.2-1.2% of the total mass of the electrolyte, the propenyl-1, 3-sultone accounts for 0.2-0.5% of the total mass of the electrolyte, and the compound accounts for 0.5-3% of the total mass of the electrolyte;
Optionally, the compound accounts for 0.5-1.5% of the total mass of the electrolyte.
17. A lithium battery comprising the electrolyte of any one of claims 8-16.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410083779.1A CN117936899A (en) | 2024-01-19 | 2024-01-19 | Electrolyte, additive thereof and lithium battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410083779.1A CN117936899A (en) | 2024-01-19 | 2024-01-19 | Electrolyte, additive thereof and lithium battery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117936899A true CN117936899A (en) | 2024-04-26 |
Family
ID=90751771
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410083779.1A Pending CN117936899A (en) | 2024-01-19 | 2024-01-19 | Electrolyte, additive thereof and lithium battery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117936899A (en) |
-
2024
- 2024-01-19 CN CN202410083779.1A patent/CN117936899A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109193029B (en) | High-nickel ternary lithium ion battery non-aqueous electrolyte and high-nickel ternary lithium ion battery containing electrolyte | |
| CN109585925B (en) | Electrolyte and lithium ion battery using same | |
| CN109671982B (en) | High-temperature high-safety electrolyte matched with silicon-carbon negative electrode material for lithium ion battery | |
| CN111900477A (en) | High-voltage lithium ion battery electrolyte film-forming additive, electrolyte and battery thereof | |
| CN109004275B (en) | Electrolyte solution and secondary battery | |
| CN113078354A (en) | Ternary lithium ion battery non-aqueous electrolyte and lithium ion battery thereof | |
| CN110690501B (en) | Electrolyte solution and electrochemical device | |
| CN112216862A (en) | High-nickel ternary lithium ion battery electrolyte and ternary lithium ion battery | |
| CN113517470A (en) | High-nickel high-voltage ternary lithium ion battery non-aqueous electrolyte and lithium ion battery | |
| CN111129590A (en) | High-voltage lithium ion battery non-aqueous electrolyte and high-voltage lithium ion battery | |
| CN112467203A (en) | High-voltage-resistant non-aqueous electrolyte for lithium ion battery and ternary high-voltage lithium ion battery | |
| CN113078358A (en) | Lithium ion battery non-aqueous electrolyte and lithium ion battery thereof | |
| CN110911754B (en) | Lithium ion battery electrolyte and preparation method thereof | |
| CN115332628A (en) | Lithium ion battery electrolyte, lithium ion battery and electric equipment | |
| CN110797544A (en) | High-performance lithium primary battery and preparation method thereof | |
| CN114552007A (en) | Non-aqueous electrolyte of lithium ion battery and lithium ion battery | |
| CN112290090A (en) | High-nickel ternary lithium ion battery non-aqueous electrolyte and battery containing electrolyte | |
| CN113078356B (en) | High-voltage lithium cobalt oxide lithium ion battery non-aqueous electrolyte and lithium ion battery | |
| CN112086684B (en) | Cesium-containing high-voltage lithium ion battery electrolyte composite additive, electrolyte and battery thereof | |
| CN110034332B (en) | Low-impedance and long-cycle-life lithium ion battery electrolyte and preparation method thereof | |
| CN111900474A (en) | Electrolyte for natural graphite cathode lithium ion battery | |
| CN113488696B (en) | High-wettability electrolyte for cylindrical lithium ion battery | |
| CN115020806A (en) | Electrolyte and lithium ion battery containing same | |
| CN115332626A (en) | Electrolyte and battery comprising same | |
| CN114464889A (en) | Non-aqueous electrolyte for high-voltage lithium ion battery and lithium ion battery thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication |