CN111370766A - Electrolyte containing-S-F group compound and electrochemical device thereof - Google Patents

Electrolyte containing-S-F group compound and electrochemical device thereof Download PDF

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CN111370766A
CN111370766A CN202010211085.3A CN202010211085A CN111370766A CN 111370766 A CN111370766 A CN 111370766A CN 202010211085 A CN202010211085 A CN 202010211085A CN 111370766 A CN111370766 A CN 111370766A
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compound
fluoride
substituted
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盖建丽
戴景杰
翟明戈
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Qingdao Binhai University
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    • 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
    • H01M2300/00—Electrolytes
    • H01M2300/0017—Non-aqueous electrolytes
    • H01M2300/0025—Organic electrolyte
    • 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 containing an-S-F group compound, which relates to the field of lithium ion batteries and also contains a nitrile compound. The invention also provides an electrochemical device, which comprises a positive plate containing the positive active material, a negative plate containing the negative active material, a separation film and the electrolyte containing the-S-F group compound, wherein the electrolyte contains the-S-F group compound and the nitrile compound, the S-F bond is easy to break, thin and compact LiF films are formed on the surfaces of the positive plate and the negative plate, the multiplying power performance and the cycling stability of the battery at room temperature are improved, and a high-temperature stable sulfate or sulfite protective film can be formed by oxidation or reduction of the LiF film, so that the high-temperature performance of the battery is improved; the nitrile compound can improve the floating charge performance of the battery cell.

Description

Electrolyte containing-S-F group compound and electrochemical device thereof
Technical Field
The invention relates to the field of lithium ion batteries, in particular to an electrolyte containing an-S-F group compound and an electrochemical device thereof.
Background
Along with the continuous promotion of people's standard of living, energy memory has become one part that modern mobile electronic product is indispensable or scarce, and lithium ion battery especially applies mobile device fields such as cell-phone, computer, unmanned aerial vehicle, electric motor car more and more extensively. At present, for a lithium ion battery, reducing the volume and increasing the energy density thereof are important research directions, wherein increasing the specific capacity of a positive electrode material is an important means for increasing the energy density. However, an increase in specific capacity (e.g., an increase in LCO voltage or an increase in Ni content in NCM) promotes oxidative decomposition of the electrolyte, which in turn increases the SEI film thickness on the positive and negative electrode surfaces, thereby reducing the service life of the battery. Therefore, it is an urgent problem to solve the cycling and storage performance of high energy density batteries.
Disclosure of Invention
The invention provides an electrolyte containing an-S-F group compound and an electrochemical device thereof, which solve the problem of poor battery cycle life when the specific capacity of a lithium ion battery is improved in the prior art.
The technical scheme of the invention is realized as follows:
an electrolyte of a compound containing an-S-F group, the compound containing an-S-F group having the general formula I:
Figure BDA0002422858120000011
wherein R1 is selected from substituted or unsubstituted C1～C12Alkyl or alkoxy, substituted or unsubstituted C2～C12Alkenyl or alkenyloxy, substituted or unsubstituted C2～C12Alkynyl or alkynyloxy, substituted or unsubstituted C3～C12Cycloalkyl or epoxyalkyl or boroxyalkyl, substituted or unsubstituted C6～C12One of aryl groups.
Alternatively, the compound of formula I is selected from at least one of the following compounds:
vinyl sulfonyl fluoride, 1-difluorosulfonyl ethane, cyclopentane-1, 3-disulfonyl fluoride, pentadecyl-1-heptanesulfonyl fluoride, perfluorooctylsulfonyl fluoride, n-butanesulfonyl fluoride, 1-perfluoropropanesulfonyl fluoride, perfluorodecansulfonyl fluoride, ben-zenesulfonyl fluoride, p-methylbenzenesulfonyl fluoride, 2-fluorobenzenesulfonyl fluoride, 2-cyano-ben-zenesulfonyl fluoride, 2-methylbenzenesulfonyl fluoride, 4-fluorobenzenesulfonyl fluoride, ethylsulfonyl fluoride, 2, 4-dimethylbenzenesulfonyl fluoride.
Optionally, the electrolyte further contains nitrile compounds including at least one of formula II, formula III, formula IV:
Figure BDA0002422858120000021
wherein R2, R3 and R4 are respectively and independently selected from substituted or unsubstituted C1～C12Alkyl or alkoxy, substituted or unsubstituted C2～C12Alkenyl or alkenyloxy, substituted or unsubstituted C2～C12Alkynyl or alkynyloxy, substituted or unsubstituted C3～C12Cycloalkyl or epoxyalkyl, substituted or unsubstituted C6～C12Aryl, wherein when substituted, the substituent is alkyl, alkenyl, alkynyl or halogen.
Alternatively, the compound of formula II, the compound of formula III, the compound of formula IV is selected from at least one of the following compounds:
1,3, 5-cyclohexanetrinitrile, 1,3, 5-benzenetricarboxylic acid, 3,4,5(2,4,5) (2,4,6) (2,3,6) -trifluoropropionitrile, tricyanomethane, methanetetracarbonitrile, terephthalonitrile, isophthalonitrile, dicyanobenzene, adiponitrile, sebaconitrile, nonadinitrile, 1, 6-dicyanoethane, pyridine-3, 4-dinitrile, 2, 5-dicyanopyridine, cis-malononitrile, tetrafluorophthalodinitrile, pyridine-2, 3-dinitrile, 4-cyanoheptanedinitrile, tetrafluoroterephthalonitrile, hexafluoroglutaronitrile, succinonitrile, ethoxymethylenemalononitrile, 1,2, 3-propanetricarbonitrile, octafluoro-1, 6-hexanenitrile, (methoxymethylene) malononitrile, hexafluorocyclotriphosphazene, ethylene-1, 1, 2-trimethylnitrile, 2,3,5, 6-pyrazine tetranitrile, 1,2,4, 5-tetracyanobenzene, propanetetranitrile, ethanetetranitrile, tetrafluorosuccinonitrile, 1,3, 6-hexanetrinitrile, fumaronitrile, p-trifluoromethylbenzonitrile, 2- (trifluoromethyl) pyridine-3-carbonitrile, 1H-1,2, 4-triazole-1-acetonitrile, ethylene glycol dipropionitrile ether.
Optionally, the electrolyte further comprises one or more of cyclic sulfonate or sulfate, carboxylic ester or fluorocarboxylic ester, fluoroether, vinylene carbonate, fluoroethylene carbonate, lithium difluorophosphate, tris (trimethylsilyl) phosphate or trivinyltrimethylcyclotrisiloxane, 1,4 dioxane, acid anhydride, and the like.
The invention also provides an electrochemical device which comprises a positive plate containing the positive active material, a negative plate containing the negative active material, a separation film and the electrolyte.
Alternatively, the positive electrode active material includes a positive electrode active material containing one or more kinds of positive electrode active materials capable of deintercalating lithium ions, a positive electrode binder, and a positive electrode conductive agent.
Optionally, the positive electrode active material includes a lithium-containing compound.
Optionally, the lithium-containing compound comprises at least one of a lithium transition metal composite oxide or a lithium transition metal phosphate compound.
Alternatively, the lithium transition metal composite oxide is an oxide containing Li and one or more transition metal elements as constituent elements.
Alternatively, the lithium transition metal phosphate compound is a phosphate compound containing Li and one or more transition metal elements as constituent elements.
Optionally, the transition metal element is one or more of Co, Ni, Mn, Fe, thereby obtaining higher voltage.
The chemical formulas of the lithium transition metal composite oxide and the lithium transition metal phosphate compound are respectively LixM1O2And LiyM2PO4. In the formula, M1And M2Respectively represents one or more transition metal elements, the values of x and y are changed along with the charge-discharge state, x is more than or equal to 0.05 and less than or equal to 1.10, and y is more than or equal to 0.05 and less than or equal to 1.10.
Optionally, the surface of the lithium-containing compound has a coating thereon, or may be mixed with another compound having a coating.
Optionally, the coating is at least one coating element compound of a coating element oxide, a coating element hydroxide, a coating element hydroxy-oxide, a coating element carbonate oxide, or a coating element hydroxy-carbonate.
Optionally, the coating element compound is amorphous or crystalline.
Optionally, the coating element is Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or mixtures thereof.
Optionally, the positive electrode conductive agent is a carbon material, a metal material, or a conductive polymer.
Optionally, the negative active material is natural graphite, artificial graphite, mesophase micro carbon spheres, hard carbon, soft carbon, silicon-carbon composite, Li-Sn alloy, Li-Sn-O alloy, Sn, SnO2Spinel-structured lithiated TiO2-Li4Ti5O12And a Li-Al alloy, wherein the silicon-carbon composite means that silicon is contained at least 10 wt% based on the weight of the silicon-carbon negative electrode active material.
Optionally, the barrier film is at least one of polyethylene, polypropylene, polyethylene terephthalate, polyimide, and aramid.
Optionally, the barrier membrane comprises a porous layer disposed on at least one surface of the barrier membrane.
Optionally, the porous layer comprises inorganic particles and a binder.
Optionally, the inorganic particles are at least one of alumina, silica, magnesia, titania, hafnia, tin oxide, ceria, nickel oxide, zinc oxide, calcium oxide, zirconia, yttria, silicon carbide, boehmite, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, and barium sulfate.
Optionally, the binder is at least one of polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene, polyamide, polyacrylonitrile, polyacrylate, polyacrylic acid, polyacrylate, sodium carboxymethyl cellulose, polyvinylpyrrolidone, polyvinyl ether, polymethyl methacrylate, polytetrafluoroethylene, and polyhexafluoropropylene.
The invention has the beneficial effects that:
the electrolyte comprises a compound containing-S-F groups and a nitrile compound, wherein S-F bonds in the compound containing-S-F groups are easy to break, thin and compact LiF films can be effectively formed on the surfaces of a positive plate and a negative plate, the multiplying power performance and the cycling stability of the battery at room temperature are improved, and a high-temperature stable sulfate or sulfite protective film can be formed by oxidation or reduction of the LiF films, so that the high-temperature performance of the battery is improved; the nitrile compound can further improve the float charge performance of the battery cell.
Detailed Description
The following description sufficiently illustrates specific embodiments herein to enable those skilled in the art to practice them. Portions and features of some embodiments may be included in or substituted for those of others. The scope of the embodiments herein includes the full ambit of the claims, as well as all available equivalents of the claims. The terms "first," "second," and the like, herein are used solely to distinguish one element from another without requiring or implying any actual such relationship or order between such elements. In practice, a first element can also be referred to as a second element, and vice versa.
The technical solutions in the embodiments of the present invention will be described clearly and completely below, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
An electrolyte of a compound containing an-S-F group, the compound containing an-S-F group having the general formula I:
Figure BDA0002422858120000051
wherein R1 is selected from substituted or unsubstituted C1～C12Alkyl or alkoxy, substituted or unsubstituted C2～C12Alkenyl or alkenyloxy, substituted or unsubstituted C2～C12Alkynyl or alkynyloxy, substituted or unsubstituted C3～C12Cycloalkyl or epoxyalkyl or boroxyalkyl, substituted or unsubstituted C6～C12One of aryl groups.
Alternatively, the compound of formula I is selected from at least one of the following compounds:
Figure BDA0002422858120000052
(vinyl sulfonyl fluoride),
Figure BDA0002422858120000053
(1, 1-difluorosulfonylethane),
Figure BDA0002422858120000054
(cyclopentane-1, 3-disulfonyl fluoride),
Figure BDA0002422858120000055
(pentadecyl-1-heptanesulfonyl fluoride),
Figure BDA0002422858120000056
(perfluorooctanesulfonyl fluoride),
Figure BDA0002422858120000057
(n-butanesulfonyl fluoride),
Figure BDA0002422858120000058
(1-perfluoropropanesulfonyl fluoride),
Figure BDA0002422858120000059
(perfluorodecanesulfonyl fluoride),
Figure BDA00024228581200000510
(Benzenesulfonyl fluoride),
Figure BDA00024228581200000511
(p-toluenesulfonyl fluoride),
Figure BDA00024228581200000512
(2-fluorobenzenesulfonyl fluoride),
Figure BDA00024228581200000513
(2-cyano-benzenesulfonyl fluoride),
Figure BDA00024228581200000514
(2-methylbenzenesulfonyl fluoride),
Figure BDA00024228581200000515
(4-fluorobenzenesulfonyl fluoride),
Figure BDA00024228581200000516
(ethylsulfonyl fluoride),
Figure BDA00024228581200000517
(2, 4-Dimethylbenzenesulfonyl fluoride).
Optionally, the electrolyte further contains nitrile compounds including at least one of formula II, formula III, formula IV:
Figure BDA0002422858120000061
wherein R2, R3 and R4 are respectively and independently selected from substituted or unsubstituted C1～C12Alkyl or alkoxy, substituted or unsubstituted C2～C12Alkenyl or alkenyloxy, substituted or unsubstituted C2～C12Alkynyl or alkynyloxy, substituted or unsubstituted C3～C12Cycloalkyl or epoxyalkyl, substituted or unsubstituted C6～C12Aryl, wherein when substituted, the substituent is alkyl, alkenyl, alkynyl or halogen.
Alternatively, the compound of formula II, the compound of formula III, the compound of formula IV is selected from at least one of the following compounds:
Figure BDA0002422858120000062
(1,3, 5-cyclohexanetricarbonitrile),
Figure BDA0002422858120000063
(1,3, 5-benzenetricyanide),
Figure BDA0002422858120000064
(3,4,5(2,4,5) (2,4,6) (2,3,6) -trifluorophenylnitrile),
Figure BDA0002422858120000065
(tricyanomethane),
Figure BDA0002422858120000066
(methanetetracarbonitrile),
Figure BDA0002422858120000067
(terephthalonitrile),
Figure BDA0002422858120000068
(m-phthalonitrile),
Figure BDA0002422858120000069
(dicyanobenzene),
Figure BDA00024228581200000610
(adiponitrile),
Figure BDA00024228581200000611
(decanedionitrile),
Figure BDA00024228581200000612
(nonanedionitrile),
Figure BDA00024228581200000613
(1, 6-dicyanoethane),
Figure BDA00024228581200000614
(pyridine-3, 4-dinitrile),
Figure BDA00024228581200000615
(2, 5-dicyanopyridine),
Figure BDA00024228581200000616
(cis-malononitrile),
Figure BDA00024228581200000617
(tetrafluorophthalonitrile),
Figure BDA00024228581200000618
(pyridine-2, 3-dicarbonitrile),
Figure BDA00024228581200000619
(4-cyanoheptanedinitrile),
Figure BDA00024228581200000620
(tetrafluoroterephthalonitrile),
Figure BDA00024228581200000621
(hexafluoroglutaronitrile),
Figure BDA00024228581200000622
(succinonitrile),
Figure BDA00024228581200000623
(ethoxymethylenemalononitrile),
Figure BDA00024228581200000624
(1,2, 3-propanetrimethylnitrile),
Figure BDA00024228581200000625
(octafluoro-1, 6-hexanedinitrile),
Figure BDA0002422858120000071
((methoxymethylene) malononitrile),
Figure BDA0002422858120000072
(hexafluorocyclotriphosphazene),
Figure BDA0002422858120000073
(ethylene-1, 1, 2-trimethylnitrile),
Figure BDA0002422858120000074
(2,3,5, 6-pyrazinetetranitrile),
Figure BDA0002422858120000075
(1,2,4, 5-tetracyanobenzene),
Figure BDA0002422858120000076
(propanetetracarbonitrile),
Figure BDA0002422858120000077
(ethanedinitrile),
Figure BDA0002422858120000078
(tetrafluorosuccinonitrile),
Figure BDA0002422858120000079
(1,3, 6-hexanetricarbonitrile),
Figure BDA00024228581200000710
(fumaric acid),
Figure BDA00024228581200000711
(p-trifluoromethylbenzonitrile),
Figure BDA00024228581200000712
(2- (trifluoromethyl) pyridine-3-carbonitrile),
Figure BDA00024228581200000713
(1H-1,2, 4-triazole-1-acetonitrile),
Figure BDA00024228581200000714
(ethylene glycol-bis-propionitrile ether).
The invention also provides an electrochemical device which comprises a positive plate containing the positive active material, a negative plate containing the negative active material, a separation film and the electrolyte.
Optionally, the electrochemical device is a lithium secondary battery.
Alternatively, the electrochemical device is a lithium metal secondary battery, a lithium ion secondary battery, a lithium polymer secondary battery, or a lithium ion polymer secondary battery.
Alternatively, the positive electrode active material includes a positive electrode active material containing one or more kinds of positive electrode active materials capable of deintercalating lithium ions, a positive electrode binder, and a positive electrode conductive agent.
Alternatively, the positive electrode active material includes a lithium-containing compound, thereby achieving a high energy density.
Optionally, the lithium-containing compound comprises at least one of a lithium transition metal composite oxide or a lithium transition metal phosphate compound.
Alternatively, the lithium transition metal composite oxide is an oxide containing Li and one or more transition metal elements as constituent elements.
Alternatively, the lithium transition metal phosphate compound is a phosphate compound containing Li and one or more transition metal elements as constituent elements.
Alternatively, the transition metal element is one or more of Co, Ni, Mn, Fe, and the like, thereby obtaining a higher voltage.
The chemical formulas of the lithium transition metal composite oxide and the lithium transition metal phosphate compound are respectively LixM1O2、LiyM2PO4. In the formula, M1And M2Respectively represents one or more transition metal elements, the values of x and y are changed along with the charge-discharge state, x is more than or equal to 0.05 and less than or equal to 1.10, and y is more than or equal to 0.05 and less than or equal to 1.10.
Alternatively, the lithium transition metal composite oxide comprises LiCoO2、LiNiO2And from the formula LiNi1-x-yMnxCoyO2The compound oxide shown.
Alternatively, the lithium transition metal phosphate compound comprises LiFePO4，LiFe1-uMnuPO4(u<1) Thereby obtaining a high battery capacity and obtaining excellent cycle characteristics.
Optionally, the surface of the lithium-containing compound has a coating thereon, or may be mixed with another compound having a coating.
Optionally, the coating is at least one coating element compound of a coating element oxide, a coating element hydroxide, a coating element hydroxy-oxide, a coating element carbonate oxide, or a coating element hydroxy-carbonate.
Optionally, the coating element compound is amorphous or crystalline.
Optionally, the coating element is Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or mixtures thereof. Using these elements in the compound, the coating can be placed by a method that does not adversely affect (or substantially does not adversely affect) the properties of the positive electrode active material.
Alternatively, the positive electrode conductive agent is a carbon material, a metal material, or a conductive polymer, and any conductive material may be used as the conductive agent as long as it does not cause chemical changes in the battery, such as natural graphite, artificial graphite, carbon black, acetylene black, ketjen black, carbon fibers, carbon nanotubes, and other carbon-based materials; a metallic material comprising metal powder or metal fibers comprising one or more of copper, nickel, aluminum or silver; conductive polymers of polyphenylene derivatives; or mixtures thereof.
The specific type of the negative electrode active material of the present invention is not particularly limited, and may be selected as desired.
Optionally, the negative active material is natural graphite, artificial graphite, mesophase micro carbon spheres (MCMB), hard carbon, soft carbon, silicon-carbon composite, Li-Sn alloy, Li-Sn-O alloy, Sn, SnO2Spinel-structured lithiated TiO2-Li4Ti5O12And a Li-Al alloy, wherein the silicon-carbon composite means that at least 10 wt% of silicon is contained based on the weight of the silicon-carbon negative electrode active material.
Optionally, the barrier film is at least one of polyethylene, polypropylene, polyethylene terephthalate, polyimide, and aramid. Among them, polyethylene and polypropylene have a good effect of preventing short circuits, and the stability of the battery can be improved by the shutdown effect. Optionally, the polyethylene is at least one of high density polyethylene, low density polyethylene, and ultra high molecular weight polyethylene.
Optionally, the barrier membrane comprises a porous layer disposed on at least one surface of the barrier membrane. The porous layer on the surface of the isolating membrane can improve the heat resistance, the oxidation resistance and the electrolyte infiltration performance of the isolating membrane and enhance the adhesion between the isolating membrane and the pole piece.
Optionally, the porous layer comprises inorganic particles and a binder.
Optionally, the inorganic particles are at least one of alumina, silica, magnesia, titania, hafnia, tin oxide, ceria, nickel oxide, zinc oxide, calcium oxide, zirconia, yttria, silicon carbide, boehmite, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, and barium sulfate.
Optionally, the binder is at least one of polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene, polyamide, polyacrylonitrile, polyacrylate, polyacrylic acid, polyacrylate, sodium carboxymethyl cellulose, polyvinylpyrrolidone, polyvinyl ether, polymethyl methacrylate, polytetrafluoroethylene, and polyhexafluoropropylene.
The following describes performance evaluation of examples and comparative examples of lithium ion batteries according to the present invention. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention.
1. Preparation of lithium ion battery
The positive electrode active material lithium cobaltate (LiCoO)2) Or LiNi0.8Co0.15Al0.05O2(NCA), a conductive agent Super P and polyvinylidene fluoride (PVDF) are mixed according to the weight ratio of 96:2:2, N-methyl pyrrolidone (NMP) is added, and the mixture is uniformly stirred under the action of a vacuum stirrer to obtain positive electrode slurry, wherein the solid content of the positive electrode slurry is 72 wt%. And uniformly coating the obtained positive electrode slurry on a positive electrode current collector aluminum foil, drying the aluminum foil coated with the positive electrode slurry at 90 ℃, and then carrying out cold pressing, cutting and slitting to obtain the positive electrode plate.
Mixing a negative electrode active material graphite, a conductive additive Super P, sodium carboxymethylcellulose (CMC) and a binder Styrene Butadiene Rubber (SBR) according to a weight ratio of 95:2:1:2, adding deionized water, and obtaining a negative electrode slurry under the action of a vacuum stirrer, wherein the solid content of the negative electrode slurry is 54 wt%; uniformly coating the negative electrode slurry on a copper foil of a negative electrode current collector; and drying the copper foil at 80 ℃, then carrying out cold pressing, cutting and slitting, and drying for 12h at 110 ℃ under a vacuum condition to obtain the negative plate.
In a dry argon atmosphere glove box, Ethylene Carbonate (EC) and propylene carbonate are addedMixing alkenyl ester (PC), Ethyl Methyl Carbonate (EMC) and diethyl carbonate (DEC) according to the weight ratio of EC: PC: EMC: DEC: 20:10:30:40, adding additives, dissolving, fully stirring, adding lithium salt LiPF6And mixing uniformly to obtain the electrolyte. Wherein, LiPF6The concentration of (2) is 1.1 mol/L. The specific types and contents of the additives used in the electrolyte are shown in the following tables. In the following table, the content of the additive is a weight percentage calculated based on the total weight of the electrolyte.
The release film was a 16 μm thick Polyethylene (PE) release film.
And sequentially stacking the positive plate, the isolating film and the negative plate to enable the isolating film to be positioned between the positive plate and the negative plate to play an isolating role, then winding and welding the tabs, then placing the tabs into an outer packaging foil aluminum-plastic film, drying, injecting the prepared electrolyte, and carrying out vacuum packaging, standing, formation, shaping, capacity test and other procedures to obtain the lithium ion battery.
2. Test method
(1) Lithium ion battery cycle performance test
LCO system: and (3) placing the lithium ion battery in a constant temperature box at 25 ℃ or 45 ℃, and standing for 30 minutes to keep the temperature of the lithium ion battery constant. The lithium ion battery reaching a constant temperature was charged at a constant current of 1C to a voltage of 4.4V, then charged at a constant voltage of 4.4V to a current of 0.05C, and then discharged at a constant current of 1C to a voltage of 3.0V, which is a charge-discharge cycle. Thus, the capacity retention ratio after the battery was cycled 100 times was calculated, respectively. The lithium ion battery cycle test data at 25 ℃ and 45 ℃ are shown in table 2.
NCA system: and (3) placing the lithium ion battery in a constant temperature box at 25 ℃ or 45 ℃, and standing for 30 minutes to keep the temperature of the lithium ion battery constant. The lithium ion battery reaching a constant temperature was charged at a constant current of 0.5C to a voltage of 4.2V, then charged at a constant voltage of 4.2V to a current of 0.05C, and then discharged at a constant current of 0.5C to a voltage of 2.8V, which is a charge-discharge cycle. Thus, the capacity retention ratio after the battery was cycled 100 times was calculated, respectively. The lithium ion battery cycle test data at 25 ℃ and 45 ℃ are shown in table 3.
(2) Method for testing storage performance
The lithium ion battery is charged to 4.4V (LCO system) or 4.2V (NCA system) at a constant current of 0.5C and charged at a constant voltage to a current of 0.05C until the battery is fully charged. Testing the thickness THK of a lithium ion battery in a fully charged state0. Placing the fully charged cell in a 60 ℃ high-temperature furnace for storage for 7 days, and testing the thickness THK of the cell1. The swelling ratio of the lithium ion battery was calculated according to the following formula:
swelling ratio (THK)1-THK0)/THK0
(3) Floating charge performance testing method
And (3) placing the LCO lithium ion battery in a constant temperature box at 45 ℃, charging to 4.4V at a constant current of 0.5C, and charging at a constant voltage until the current is 0.05C until the battery is in a full charge state. And testing the thickness of the lithium ion battery in a full-charge state. Then, constant voltage charging of 4.4V was continued, and the thickness of the lithium ion battery was tested every 2 days. And (4) calculating the expansion rate of the lithium ion battery (the calculation formula is the same as the above), and recording the constant-voltage charging time when the expansion rate of the battery reaches 10%.
3. Test results
EXAMPLES arranging as shown in Table 1, the-S-F group-containing compounds were perfluorooctylsulfonyl fluoride (labeled 1), vinyl sulfonyl fluoride (labeled 2); the nitrile compound is hexanetricarbonitrile (labeled 1) and ethylene glycol dipropionitrile ether (labeled 2).
Table 1: DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION
Figure BDA0002422858120000111
Table 2: LCO System Performance test results
Figure BDA0002422858120000112
Table 3: NCA System Performance test results
Figure BDA0002422858120000121
By comparing examples 1-12 with comparative example 1, the addition of the compound containing the-S-F group to the electrolyte can improve the high-rate cycle and storage performance of the battery at room temperature; example 3 compares with examples 7 and 8, and it is found that the nitrile compound can further improve the float charge performance of the battery.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (10)

1. An electrolyte solution of a compound having an-S-F group, wherein the compound having an-S-F group has a general formula of formula I:
Figure FDA0002422858110000011
wherein R1 is selected from substituted or unsubstituted C1～C12Alkyl or alkoxy, substituted or unsubstituted C2～C12Alkenyl or alkenyloxy, substituted or unsubstituted C2～C12Alkynyl or alkynyloxy, substituted or unsubstituted C3～C12Cycloalkyl or epoxyalkyl or boroxyalkyl, substituted or unsubstituted C6～C12One of aryl groups.
2. The electrolyte of claim 1, wherein the compound of formula I is selected from at least one of the following compounds:
vinyl sulfonyl fluoride, 1-difluorosulfonyl ethane, cyclopentane-1, 3-disulfonyl fluoride, pentadecyl-1-heptanesulfonyl fluoride, perfluorooctylsulfonyl fluoride, n-butanesulfonyl fluoride, 1-perfluoropropanesulfonyl fluoride, perfluorodecansulfonyl fluoride, native sulfonyl fluoride, p-methylbenzenesulfonyl fluoride, 2-fluorobenzenesulfonyl fluoride, 2-cyano-native sulfonyl fluoride, 2-methylbenzenesulfonyl fluoride, 4-fluorobenzenesulfonyl fluoride, ethylsulfonyl fluoride, 2, 4-dimethylbenzenesulfonyl fluoride.
3. The electrolyte of claim 1, wherein the electrolyte further comprises a nitrile compound including at least one of formula II, formula III, and formula IV:
Figure FDA0002422858110000012
wherein R2, R3 and R4 are respectively and independently selected from substituted or unsubstituted C1～C12Alkyl or alkoxy, substituted or unsubstituted C2～C12Alkenyl or alkenyloxy, substituted or unsubstituted C2～C12Alkynyl or alkynyloxy, substituted or unsubstituted C3～C12Cycloalkyl or epoxyalkyl, substituted or unsubstituted C6～C12Aryl, wherein when substituted, the substituent is alkyl, alkenyl, alkynyl or halogen.
4. The electrolyte of claim 3, wherein the compound of formula II, the compound of formula III, and the compound of formula IV are selected from at least one of the following compounds:
1,3, 5-cyclohexanetrinitrile, 1,3, 5-benzenetricarbonitrile, 3,4,5(2,4,5) (2,4,6) (2,3,6) -trifluoropropionitrile, tricyanomethane, methanetetracarbonitrile, terephthalonitrile, isophthalonitrile, dicyanobenzene, adiponitrile, sebaconitrile, nonadinitrile, 1, 6-dicyanoethane, pyridine-3, 4-dinitrile, 2, 5-dicyanopyridine, cis-malononitrile, tetrafluorophthalodinitrile, pyridine-2, 3-dinitrile, 4-cyanoheptanedinitrile, tetrafluoroterephthalonitrile, hexafluoroglutaronitrile, succinonitrile, ethoxymethylenemalononitrile, 1,2, 3-propanetricarbonitrile, octafluoro-1, 6-hexane, (methoxymethylene) malononitrile, hexafluorocyclotriphosphazene, ethylene-1, 1, 2-trimethylnitrile, 2,3,5, 6-pyrazine tetracyanonitrile, 1,2,4, 5-tetracyanobenzene, propanetetracyanonitrile, ethanetetracyanonitrile, tetrafluorosuccinonitrile, 1,3, 6-hexanetrinitrile, fumaronitrile, p-trifluoromethylbenzonitrile, 2- (trifluoromethyl) pyridine-3-carbonitrile, 1H-1,2, 4-triazole-1-acetonitrile, ethylene glycol dipropionitrile ether.
5. The electrolyte of claim 1, wherein the electrolyte further comprises one or more of cyclic sulfonate or sulfate, carboxylate or fluorocarboxylate, fluoroether, vinylene carbonate, fluoroethylene carbonate, lithium difluorophosphate, tris (trimethylsilyl) phosphate or trivinyltrimethylcyclotrisiloxane, 1, 4-dioxane, and anhydride.
6. An electrochemical device comprising a positive electrode sheet containing a positive electrode active material, a negative electrode sheet containing a negative electrode active material, a separator and an electrolyte, wherein the electrolyte is the electrolyte containing the-S-F group-containing compound according to any one of claims 1 to 5.
7. The electrochemical device according to claim 6, wherein the positive electrode active material comprises one or more positive electrode active materials capable of releasing and inserting lithium ions, a positive electrode binder, and a positive electrode conductive agent, the positive electrode active material is a lithium-containing compound, the lithium-containing compound comprises at least one of a lithium transition metal composite oxide and a lithium transition metal phosphate compound, and the chemical formulas of the lithium transition metal composite oxide and the lithium transition metal phosphate compound are LixM1O2And LiyM2PO4Wherein M is1And M2Respectively represents one or more transition metal elements, x is more than or equal to 0.05 and less than or equal to 1.10, and y is more than or equal to 0.05 and less than or equal to 1.10.
8. An electrochemical device As in claim 7, wherein said lithium-containing compound has a coating on its surface or is mixed with another compound having a coating of at least one coating element compound selected from the group consisting of an oxide of a coating element, a hydroxide of a coating element, a oxyhydroxide of a coating element, a carbonate of a coating element, and a hydroxycarbonate of a coating element, said coating element being Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or mixtures thereof.
9. The electrochemical device according to claim 6, wherein the negative active material is natural graphite, artificial graphite, mesophase micro carbon spheres, hard carbon, soft carbon, silicon-carbon composite, Li-Sn alloy, Li-Sn-O alloy, Sn, SnO, or the like2Spinel-structured lithiated TiO2-Li4Ti5O12And a Li-Al alloy, wherein the silicon-carbon composite means that at least 10 wt% of silicon is contained based on the weight of the silicon-carbon negative electrode active material.
10. The electrochemical device as recited in claim 6, wherein the separator comprises a porous layer disposed on at least one surface of the separator.
CN202010211085.3A 2020-03-24 2020-03-24 Electrolyte containing-S-F group compound and electrochemical device thereof Pending CN111370766A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112831798A (en) * 2020-12-29 2021-05-25 中船重工（邯郸）派瑞特种气体有限公司 Multistage tubular electrolysis device for preparing octafluoropropane and preparation method
CN114552014A (en) * 2022-02-25 2022-05-27 惠州锂威新能源科技有限公司 Electrolyte and electrochemical device containing same

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105703007A (en) * 2016-03-30 2016-06-22 珠海市赛纬电子材料股份有限公司 Non-aqueous electrolyte for high-voltage rapid-charging type lithium ion battery
US20160261000A1 (en) * 2014-09-10 2016-09-08 Battelle Memorial Institute Anode-free rechargeable battery
CN109301162A (en) * 2013-03-27 2019-02-01 三菱化学株式会社 Nonaqueous electrolytic solution and the nonaqueous electrolyte battery for using the nonaqueous electrolytic solution

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109301162A (en) * 2013-03-27 2019-02-01 三菱化学株式会社 Nonaqueous electrolytic solution and the nonaqueous electrolyte battery for using the nonaqueous electrolytic solution
US20160261000A1 (en) * 2014-09-10 2016-09-08 Battelle Memorial Institute Anode-free rechargeable battery
CN105703007A (en) * 2016-03-30 2016-06-22 珠海市赛纬电子材料股份有限公司 Non-aqueous electrolyte for high-voltage rapid-charging type lithium ion battery

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112831798A (en) * 2020-12-29 2021-05-25 中船重工（邯郸）派瑞特种气体有限公司 Multistage tubular electrolysis device for preparing octafluoropropane and preparation method
CN114552014A (en) * 2022-02-25 2022-05-27 惠州锂威新能源科技有限公司 Electrolyte and electrochemical device containing same

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