CN115443569A - Electrolyte, electrochemical device containing electrolyte and electronic device - Google Patents

Electrolyte, electrochemical device containing electrolyte and electronic device Download PDF

Info

Publication number
CN115443569A
CN115443569A CN202180026202.1A CN202180026202A CN115443569A CN 115443569 A CN115443569 A CN 115443569A CN 202180026202 A CN202180026202 A CN 202180026202A CN 115443569 A CN115443569 A CN 115443569A
Authority
CN
China
Prior art keywords
electrolyte
substituted
formula
unsubstituted
compound
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
Application number
CN202180026202.1A
Other languages
Chinese (zh)
Inventor
彭谢学
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ningde Amperex Technology Ltd
Original Assignee
Ningde Amperex Technology Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Ningde Amperex Technology Ltd filed Critical Ningde Amperex Technology Ltd
Publication of CN115443569A publication Critical patent/CN115443569A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0566—Liquid materials
    • H01M10/0567—Liquid materials characterised by the additives
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
    • 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

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Inorganic Chemistry (AREA)
  • Secondary Cells (AREA)
  • Electric Double-Layer Capacitors Or The Like (AREA)

Abstract

An electrolyte, an electrochemical device and an electronic device including the same are provided, wherein the electrolyte includes a compound of formula (I-A). The electrolyte comprising the compound of the formula (I-A) is applied to an electrochemical device, so that a stable anode solid interface film can be formed on the surface of a positive electrode of the electrochemical device, and a stable cathode solid interface film can be formed on the surface of a negative electrode of the electrochemical device, and the cycle performance and the high-temperature storage performance of the electrochemical device are effectively improved. The electronic device comprising the electrochemical device also has good high-temperature storage performance and cycle performance.

Description

Electrolyte, electrochemical device containing electrolyte and electronic device
Technical Field
The application relates to the field of electrochemistry, in particular to an electrolyte, an electrochemical device containing the electrolyte and an electronic device.
Background
As a new type of movable energy storage device, a secondary battery (e.g., a lithium ion battery) has characteristics of high energy density, high operating voltage, long cycle life, no memory effect, environmental friendliness, etc., and is widely used in the field of portable small electronic devices such as mobile phones, notebook computers, cameras, etc., and is gradually expanded to the fields of large-scale electric transportation work and renewable energy storage. With the wide application of lithium ion batteries in the above fields, people have higher and higher requirements on energy density of lithium ion batteries.
In order to further increase the energy density of lithium ion batteries, methods of increasing the charging voltage or increasing the capacity of the active material are generally employed. However, both methods can accelerate the decomposition of the electrolyte in the lithium ion battery, and further degrade the cycle performance and the high-temperature (not less than 60 ℃) storage performance of the lithium ion battery.
Disclosure of Invention
An electrolyte, an electrochemical device and an electronic device including the same are provided to improve cycle performance and high-temperature storage performance of the electrochemical device.
In a first aspect, the present application provides an electrolyte comprising a compound of formula (I-a):
Figure BDA0003872501210000011
wherein A is 1 Selected from the subunits of formula (I-B), formula (I-C), or formula (I-D):
Figure BDA0003872501210000012
x and Y are each independently selected from a subunit of formula (I-E), a subunit of formula (I-F), a subunit of formula (I-G), or a subunit of formula (I-H):
Figure BDA0003872501210000013
Figure BDA0003872501210000021
represents a binding site to an adjacent atom; r 12 And R 17 Each independently selected from substituted or unsubstituted C 1 To C 10 Alkyl of (2)Substituted or unsubstituted C 2 To C 10 Alkenyl of (a), substituted or unsubstituted C 2 To C 10 Alkynyl, substituted or unsubstituted C 6 To C 10 Aryl, substituted or unsubstituted C 3 To C 10 Alicyclic hydrocarbon group of (1), substituted or unsubstituted C 1 To C 10 Lipoheterocyclic group of (A), substituted or unsubstituted C 1 To C 10 When substituted, each substituent is independently selected from halogen atoms; r 11 、R 13 、R 14 、R 15 、R 16 、R 18 And R 19 Each independently selected from the group consisting of a single bond, substituted or unsubstituted C 1 To C 10 Alkylene of (a), substituted or unsubstituted C 2 To C 10 Alkenylene group of (a), substituted or unsubstituted C 2 To C 10 Alkynylene of (a), substituted or unsubstituted C 6 To C 10 Arylene of (a), substituted or unsubstituted C 3 To C 10 Alicyclic hydrocarbon group of (a), substituted or unsubstituted C 1 To C 10 Of (a) a heterocyclylene group, substituted or unsubstituted C 1 To C 10 When substituted, each substituent is independently selected from halogen atoms; the heteroatoms in the aliphatic heterocyclic group, aromatic heterocyclic group, aliphatic heterocyclic group, and aromatic heterocyclic group each independently comprise N, S or O.
The electrolyte comprising the compound of the formula (I-A) is applied to an electrochemical device, so that a stable anode solid interface film is formed on the surface of a positive electrode of the electrochemical device, a stable cathode solid interface film is formed on the surface of a negative electrode of the electrochemical device, the stability of the surface of the positive electrode and the surface of the negative electrode is further improved, and the continuous decomposition of the electrolyte at high temperature is inhibited, thereby improving the cycle performance and the high-temperature storage performance of the electrochemical device.
Preferably, the compound of formula (I-A) includes at least one of the following compounds (I-1) to (I-38):
Figure BDA0003872501210000022
Figure BDA0003872501210000031
in one embodiment of the present application, the mass percentage W of the compound of formula (I-a) is based on the mass of the electrolyte I 0.01% to 5%, preferably 0.1% to 1%. For example, W I The value of (b) may be 0.01%, 0.1%, 0.5%, 1%, 3%, 5%, or any value between any two of the above numerical ranges. By mixing the mass percent W of the compound of the formula (I-A) I The control within the above range is more advantageous for improving the cycle performance and high-temperature storage performance of the electrochemical device.
In one embodiment of the present application, the electrolyte further comprises a compound of formula (II-a):
Figure BDA0003872501210000032
wherein R is 21 And R 22 Each independently selected from substituted or unsubstituted C 1 To C 5 Alkyl, substituted or unsubstituted C 2 To C 5 Alkenyl, substituted or unsubstituted C 2 To C 5 When substituted, each substituent is independently selected from halogen or methyl, R 21 And R 22 A closed loop structure may be constructed.
The compound of the formula (II-A) is added into the electrolyte, so that the stability of the surface of the anode and the surface of the cathode can be further improved, the continuous decomposition of the electrolyte at high temperature can be inhibited, the consumption required by the redox reaction of the electrolyte can be reduced, the gas generation of the electrolyte can be inhibited, and the cycle performance and the high-temperature storage performance of the electrochemical device can be further improved.
Preferably, the compound of formula (II-A) includes at least one of the following compounds (II-1) to (II-12):
Figure BDA0003872501210000041
in one embodiment of the present application, the electrolyte satisfies at least one of the following (a) or (b): (a) The mass percentage content W of the compound of formula (II-A) based on the mass of the electrolyte II From 0.05% to 3%, preferably from 0.1% to 1%; (b) The mass percentage content W of the compound of formula (I-A) based on the mass of the electrolyte I W is the mass percentage of the compound of the formula (II-A) II Satisfies the following conditions: w is more than 0 I /W II 10 or less, preferably 0.25 or less W I /W II ≤5。
For example, W II The value of (d) may be 0.05%, 0.1%, 1%, 2%, 3%, or any value between any two of the above numerical ranges. By mixing the mass percentage W of the compound of the formula (II-A) II The control within the above range is more advantageous for improving the cycle performance and high-temperature storage performance of the electrochemical device.
For example, W I /W II The value of (d) may be 0.1, 0.17, 0.25, 0.5, 5, 10, or any value between any two of the above numerical ranges. By mixing W I /W II The value of (A) is controlled within the above range, so that the compound of formula (I-A) and the compound of formula (II-A) exert a synergistic effect, and the cycle performance and the high-temperature storage performance of the electrochemical device are more favorably improved.
In one embodiment of the present application, the electrolyte further comprises a first lithium salt comprising lithium difluorophosphate (LiPO) 2 F 2 ) At least one of lithium difluorobis (oxalato) phosphate (LiDFOP) or lithium tetrafluoro (oxalato) phosphate. The addition of the first lithium salt in the electrolyte can further improve the film forming effect of the anode solid interface film on the surface of the anode, reduce the contact between the electrolyte and the anode and inhibit the gas generation of the electrolyte. Thereby further improving the cycle performance and high-temperature storage performance of the electrochemical device.
In one embodiment of the present application, the mass percentage content W of the first lithium salt is based on the mass of the electrolyte L1 Is 0.1% to 1%. For example, W L1 The value of (b) may be 0.1%, 0.3%, 0.8%, 1%, or any value between any two of the above numerical ranges. By containing the first lithium salt in percentage by massQuantity W L1 The control within the above range is more advantageous for improving the cycle performance and high-temperature storage performance of the electrochemical device.
In one embodiment of the present application, the electrolyte further includes a sulfur-oxygen double bond compound, the sulfur-oxygen double bond compound including a compound of formula (III-a):
Figure BDA0003872501210000042
wherein A is 3 Any one selected from the group consisting of a subunit of formula (III-B), a subunit of formula (III-C), a subunit of formula (III-D), a subunit of formula (III-E), a subunit of formula (III-F), a subunit of formula (III-G), a subunit of formula (III-H), and a subunit of formula (III-I):
Figure BDA0003872501210000051
Figure BDA0003872501210000052
represents a binding site to an adjacent atom; r 31 And R 32 Each independently selected from substituted or unsubstituted C 1 To C 5 Alkyl, substituted or unsubstituted C 2 To C 10 Alkenyl of (a), substituted or unsubstituted C 2 To C 10 Alkynyl, substituted or unsubstituted C 3 To C 10 An alicyclic group of (A), substituted or unsubstituted C 6 To C 10 Aryl, substituted or unsubstituted C 1 To C 6 Lipoheterocyclic group of (A), substituted or unsubstituted C 1 To C 6 Aryl heterocyclic group of (1), substituted or unsubstituted C 1 To C 3 When substituted, each substituent is independently selected from halogen atom, C 1 To C 3 Alkyl of (C) 2 To C 3 Alkenyl or C 2 To C 3 Alkynyl of R 31 And R 32 A closed loop structure can be formed; the heteroatoms in the aliphatic and aromatic heterocyclic groups each independently comprise N, S orO。
The addition of the sulfur-oxygen double bond compound in the electrolyte can enhance the oxidation resistance of the electrolyte, reduce the possibility of oxidation of the anode active material, and form a layer of protective film on the surface of the metal lithium under the condition that the lithium is separated from the cathode, thereby inhibiting the decomposition and heat generation of the metal lithium and the electrolyte, enhancing the protection of the anode active material and the anode active material, and further improving the cycle performance, high-temperature storage performance and floating charge performance of the electrochemical device.
Preferably, the compound of formula (III-A) includes at least one of the following compounds (III-1) to (III-53):
Figure BDA0003872501210000053
Figure BDA0003872501210000061
more preferably, the compound of formula (III-a) comprises at least one of the following compounds:
Figure BDA0003872501210000062
in one embodiment of the present application, the electrolyte satisfies at least one of the following (c) or (d):
(c) Based on the mass of the electrolyte, the mass percentage content W of the sulfur-oxygen double bond compound S From 0.01% to 10%, preferably from 0.1% to 8%;
(d) The mass percentage content W of the compound of formula (I-A) based on the mass of the electrolyte I The mass percentage content W of the compound having a double bond with sulfur and oxygen S Satisfies the following conditions: w is more than 0 I /W S 1 or less, preferably 0.1 or less W I /W S ≤0.3。
For example, W S The value of (d) may be 0.01%, 0.1%, 4%, 8%, 10%, or any value between any two of the above numerical ranges. The mass percentage content W of the sulfur-oxygen double bond compound S The control within the above range is more favorable for improving the cycle performance, high-temperature storage performance and floating charge performance of the electrochemical device.
For example, W I /W S May be 0.01, 0.063, 0.1, 0.125, 0.3, 0.5, 1, or any number between any two of the above numerical ranges. W is to be I /W S The value of (A) is controlled within the above range, so that the compound of formula (I-A) and the sulfur-oxygen double bond compound exert a synergistic effect, and the cycle performance, the high-temperature storage performance and the floating charge performance of the electrochemical device are improved more favorably.
In one embodiment of the present application, the electrolyte further includes a polynitrile compound including at least one of the following compounds (i-1) to (i-16):
Figure BDA0003872501210000071
the addition of the polynitrile compound in the electrolyte enables the compound in the formula (I-A) and the polynitrile compound to play a synergistic role, and further improves the high-temperature storage performance and the floating charge performance of the electrochemical device.
In one embodiment of the present application, the mass percentage content W of the polynitrile compound based on the mass of the electrolyte D From 0.3% to 10%, preferably from 2% to 10%. For example, W D The value of (b) may be 0.3%, 1%, 2.5%, 3%, 5%, 10%, or any value between any two of the above numerical ranges. By mixing the mass percent W of the polynitrile compound D The control within the above range is more advantageous for improving the high-temperature storage performance and the float charge performance of the electrochemical device.
In one embodiment of the present application, the electrolyte further includes a first non-aqueous organic solvent including at least one of a cyclic carbonate, a chain carbonate, or a carboxylic ester. The addition of the first non-aqueous organic solvent in the electrolyte can further enhance the stability of the anode solid interface film on the surface of the anode and the cathode solid interface film on the surface of the cathode, improve the flexibility of the anode solid interface film and the cathode solid interface film, further increase the protection effect on the anode active material and the cathode active material, reduce the contact probability of the anode active material or the cathode active material and the electrolyte, and inhibit the increase of impedance in the circulation process of the electrochemical device, thereby further improving the circulation performance and the high-temperature storage performance of the electrochemical device.
In one embodiment of the present application, the cyclic carbonate comprises Sup>A compound of formulSup>A (IV-A):
Figure BDA0003872501210000081
wherein R is 4 Selected from substituted or unsubstituted C 1 To C 6 Alkylene, substituted or unsubstituted C 2 To C 6 Alkenylene, when substituted, each substituent is independently selected from halogen atom, C 1 To C 6 Alkyl or C 2 To C 6 An alkenyl group.
Preferably, the compound of formulSup>A (IV-A) includes at least one of the following compounds (IV-1) to (IV-12):
Figure BDA0003872501210000082
in one embodiment of the present application, the chain carbonate includes at least one of dimethyl carbonate, methylethyl carbonate, fluoromethyl methyl carbonate, bis (fluoromethyl) carbonate, difluoromethyl methyl carbonate, ethyl (fluoromethyl) carbonate, difluoromethyl ethyl carbonate, 2-fluoroethyl methyl carbonate, 2-fluoroethyl (fluoromethyl) carbonate, 2,2-difluoroethyl methyl carbonate, 2,2-difluoroethyl carbonate, 2,2,2-trifluoroethyl carbonate, ethyl (2-fluoroethyl) carbonate, bis (2-fluoroethyl) carbonate, 2,2-difluoroethyl (2-fluoroethyl) carbonate, bis (2,2-difluoroethyl) carbonate, bis (2,2,2-trifluoroethyl) carbonate, methylpropyl carbonate, or ethylpropyl carbonate; the carboxylic acid ester comprises at least one of methyl formate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl Propionate (EP), 2,2-difluoroethyl acetate, or 2,2-difluoroethyl acetate.
In one embodiment of the present application, the electrolyte satisfies at least one of the following (e) to (g):
(e) Based on the mass of the electrolyte, the mass percentage content W of the cyclic carbonate H From 0.01% to 30%, preferably from 0.1% to 30%;
(f) The mass ratio of the cyclic carbonate to the chain carbonate is (10-60) to 40;
(g) The mass ratio of the cyclic carbonate to the carboxylic ester is (10-60) to (20-60).
For example, W H The value of (d) may be 0.01%, 5%, 15%, 20%, 25%, 30%, or any value between any two of the above numerical ranges. The mass percentage of the cyclic carbonate W H The control within the above range is more advantageous for improving the cycle performance and high-temperature storage performance of the electrochemical device. W H The value of (b) is controlled within the above preferable range, and the cycle performance of the electrochemical device can be further improved.
For example, the mass ratio of the cyclic carbonate to the chain carbonate may be 10. The mass ratio of the cyclic carbonate to the chain carbonate is controlled within the above range, so that the cyclic carbonate and the chain carbonate exert a synergistic effect, and the cycle performance and the high-temperature storage performance of the electrochemical device are improved.
For example, the mass ratio of cyclic carbonate to carboxylate may be 10, 15, 55. The mass ratio of the cyclic carbonate to the carboxylic ester is controlled within the above range, so that the cyclic carbonate and the carboxylic ester exert a synergistic effect, and the cycle performance and the high-temperature storage performance of the electrochemical device are improved.
In one embodiment of the present application, the electrolyte further includes Sup>A second lithium salt including Sup>A compound of formulSup>A (V-Sup>A):
Figure BDA0003872501210000091
wherein A is 51 、A 52 、A 53 And A 54 Each independently selected from a halogen atom, a group of formula (V-B), a group of formula (V-C) or a group of formula (V-D), A 51 、A 52 、A 53 And A 54 Wherein two adjacent groups may form a closed ring structure:
Figure BDA0003872501210000092
Figure BDA0003872501210000093
represents a binding site to an adjacent atom; o in the two binding sites of the group of formula (V-C) is linked to B, k is 0 or 1; r 51 And R 53 Each independently selected from substituted or unsubstituted C 1 To C 6 Alkyl, substituted or unsubstituted C 2 To C 6 When substituted, each substituent is independently selected from halogen atoms; r 52 Selected from substituted or unsubstituted C 1 To C 6 Alkylene of (a), substituted or unsubstituted C 2 To C 6 When substituted, each substituent is independently selected from halogen atoms.
Preferably, the compound of formulSup>A (V-A) comprises lithium tetrafluoroborate (LiBF) 4 ) Lithium bis (oxalato) borate (LiB (C) 2 O 4 ) 2 LiBOB) or lithium difluorooxalato borate (LiBF) 2 (C 2 O 4 ) LiDFOB).
The second lithium salt is added into the electrolyte, so that a positive solid interfacial film can be formed on the surface of the positive electrode, and/or a negative solid interfacial film can be formed on the surface of the negative electrode, the stability of the positive electrode/electrolyte and negative electrode/electrolyte interfaces is maintained, and the cycle performance, the floating charge performance and the high-temperature storage performance of the electrochemical device are further improved.
In one embodiment of the present application, the mass percentage content W of the second lithium salt is based on the mass of the electrolyte L2 Is 0.1 to 2 percent. For example, W L2 The value of (b) may be 0.1% or 0.3%0.5%, 1%, 2%, or any value between any two of the above numerical ranges. The mass percentage content W of the second lithium salt L2 The control within the range is more favorable for improving the cycle performance, the floating charge performance and the high-temperature storage performance of the electrochemical device.
The electrolyte of the present application may further include a third lithium salt. The third lithium salt is not particularly limited as long as the object of the present invention can be achieved. For example, the third lithium salt includes lithium hexafluorophosphate (LiPF) 6 ) Lithium hexafluoroantimonate (LiSbF) 6 ) Lithium hexafluoroarsenate (LiAsF) 6 ) Lithium perfluorobutylsulfonate (LiC) 4 F 9 SO 3 ) Lithium perchlorate (LiClO) 4 ) Lithium aluminate (LiAlO) 2 ) Lithium aluminum tetrachloride (LiAlCl) 4 ) Lithium bis (sulfonimide) (LiN (C) x F 2x+1 SO 2 )(C y F 2y+1 SO 2 ) Wherein x and y are each independently selected from at least one of natural numbers 0 to 6), lithium chloride (LiCl), lithium fluoride (LiF).
The electrolyte of the present application may further include a second non-aqueous organic solvent. The second non-aqueous organic solvent is not particularly limited in kind in the present application as long as the object of the present application can be achieved. For example, the second non-aqueous organic solvent may include an ether-based solvent, a sulfone-based solvent, or other organic solvents. The ether solvent may include at least one of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, dibutyl ether, tetrahydrofuran, 2-methyltetrahydrofuran, or bis (2,2,2-trifluoroethyl) ether. The sulfone solvent may include at least one of ethyl vinyl sulfone, methyl isopropyl sulfone, dimethyl sulfoxide, 1,2-dioxolane, sulfolane, methyl sulfolane, isopropyl sec-butyl sulfone, or sulfolane. Other organic solvents may include at least one of 1,3-dimethyl-2-imidazolidinone, N-methyl-2-pyrrolidone, formamide, dimethylformamide, acetonitrile, trimethyl phosphate, triethyl phosphate, trioctyl phosphate, phosphate esters, propyl propionate, ethylene carbonate (also known as ethylene carbonate, abbreviated as EC), propylene carbonate (also known as propylene carbonate, abbreviated as PC), or diethyl carbonate (DEC). The second non-aqueous organic solvent is present in an amount of 5 to 90% by mass based on the mass of the electrolyte. For example, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or any number between any two of the above numerical ranges.
In a second aspect, the present application provides an electrochemical device comprising an electrolyte as described in any one of the previous aspects. Therefore, the electrochemical device of the present application has good cycle performance and high-temperature storage performance.
In the present application, the electrochemical device may further include a positive electrode, and the positive electrode generally includes a positive electrode current collector and a positive electrode material layer, and in the present application, the positive electrode current collector is not particularly limited as long as the object of the present application can be achieved, and may include, but is not limited to, an aluminum foil, an aluminum alloy foil, a composite current collector, or the like, for example. In the present application, the thickness of the positive electrode current collector is not particularly limited as long as the object of the present application can be achieved, and is, for example, 8 μm to 12 μm. In the present application, the positive electrode material layer may be provided on one surface in the thickness direction of the positive electrode current collector, and may also be provided on both surfaces in the thickness direction of the positive electrode current collector. The "surface" herein may be the entire region of the positive electrode current collector or a partial region of the positive electrode current collector, and the present application is not particularly limited as long as the object of the present application can be achieved.
In the present application, the positive electrode active material is included in the positive electrode material layer, and the present application does not particularly limit the positive electrode active material as long as the object of the present application can be achieved, and may include, for example, at least one of a complex oxide, sulfide, selenide, or halide of lithium or a transition metal element. The transition metal element is not particularly limited as long as the object of the present invention can be achieved, and may include at least one of nickel, manganese, cobalt, or iron, for example. Specifically, the positive active material may include LiCoO 2 、LiNiO 2 、LiMnO 2 、LiMn 2 O 4 、Li(Ni a1 Co b1 Mn c1 )O 2 (0<a1<1，0<b1<1，0<c1<1，a1+b1+c1＝1)、LiMn 2 O 4 LiNi 1-y1 Co y1 O 2 (0<y1<1)、LiCo l-y2 Mn y2 O 2 (0<y2<1)、LiNi l-y3 Mn y3 O 2 (0<y3<1)、Li(Ni a2 Mn b2 Co c2 )O 4 (0<a2<2，0<b2<2，0<c2<2，a2+b2+c2＝2)、LiMn 2-z1 Ni z1 O 4 (0<z1<2)、LiMn 2- z2 Co z2 O 4 (0<z2<2)、Li(Ni a3 Co b3 Al c3 )O 2 (0<a3<1，0<b3<1，0<c3<1，a3+b3+c3＝1)、LiCoPO 4 Or LiFePO 4 At least one of (a).
Alternatively, the positive electrode active material has a coating layer on the surface, and the compound of the coating layer is not particularly limited as long as the object of the present application can be achieved, and for example, the compound of the coating layer may be amorphous or crystalline, and the compound of the coating layer may include, but is not limited to, at least one of an oxide of the coating element, a hydroxide of the coating element, a oxyhydroxide of the coating element, an oxycarbonate of the coating element, or an oxycarbonate of the coating element. The coating element may include, but is not limited to, at least one of Mg, al, co, K, na, ca, si, ti, V, sn, ge, ga, B, as, or Zr. The method for preparing the coating layer is not particularly limited, and a method known in the art, such as a spraying method or a dipping method, may be used as long as the object of the present application can be achieved.
The positive electrode material layer may further include a positive electrode binder, and the present application has no particular limitation as long as the object of the present application can be achieved, and may include, for example, but not limited to, at least one of polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, diacetyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, ethylene oxide-containing polymer, polyvinyl pyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, acrylated styrene-butadiene rubber, epoxy resin, or nylon.
In the present application, the positive electrode material layer may further include a conductive agent, and the conductive agent is not particularly limited as long as the object of the present application can be achieved, and may include, for example, but not limited to, at least one of natural graphite, artificial graphite, conductive carbon black (Super P), carbon Nanotubes (CNTs), carbon fibers, flake graphite, ketjen black, graphene, a metal material, or a conductive polymer. The carbon nanotubes may include, but are not limited to, single-walled carbon nanotubes and/or multi-walled carbon nanotubes. The carbon fibers may include, but are not limited to, vapor Grown Carbon Fibers (VGCF) and/or carbon nanofibers. The metal material may include, but is not limited to, metal powder and/or metal fiber, and specifically, the metal may include, but is not limited to, at least one of copper, nickel, aluminum, or silver. The above-mentioned conductive polymer may include, but is not limited to, at least one of polyphenylene derivatives, polyaniline, polythiophene, polyacetylene, or polypyrrole.
Optionally, the positive electrode may further include a conductive layer between the positive current collector and the positive material layer. The composition of the conductive layer is not particularly limited in the present application, and may be a conductive layer commonly used in the art, and may include, for example, but not limited to, the above-mentioned conductive agent and the above-mentioned positive electrode binder.
In the present application, the electrochemical device may further include a negative electrode, and the negative electrode generally includes a negative electrode current collector, and the present application does not particularly limit the negative electrode current collector as long as the object of the present application can be achieved, and for example, may include, but is not limited to, a copper foil, a copper alloy foil, a nickel foil, a stainless steel foil, a titanium foil, a nickel foam, a copper foam, a composite current collector, or the like. In the present application, the thickness of the current collector of the negative electrode is not particularly limited as long as the object of the present application can be achieved, and is, for example, 4 to 12 μm. In the present application, the negative electrode material layer may be provided on one surface in the thickness direction of the negative electrode current collector, and may also be provided on both surfaces in the thickness direction of the negative electrode current collector. The "surface" herein may be the entire region of the negative electrode current collector or a partial region of the negative electrode current collector, and the present application is not particularly limited as long as the object of the present application can be achieved.
In the present application, the anode material layer includes an anode active material, wherein the anode active material is not particularly limited as long as the object of the present application can be achieved, and for example, may include, but is not limited to, at least one of a material that reversibly intercalates/deintercalates lithium ions, lithium metal, a lithium metal alloy, a material that can dope/dedope lithium, or a transition metal oxide.
The material that reversibly intercalates/deintercalates lithium ions may include, but is not limited to, carbon materials including crystalline carbon and/or amorphous carbon. Crystalline carbon may include, but is not limited to, amorphous or platy, platelet-shaped, spherical, or fibrous natural graphite, synthetic graphite, pyrolytic carbon, mesophase pitch-based carbon fibers, mesophase carbon microbeads, mesophase pitch, or high temperature calcined carbon (such as petroleum or coke derived from coal tar pitch). The amorphous carbon may include, but is not limited to, at least one of soft carbon, hard carbon, mesophase pitch carbonization products, or fired coke. The lithium metal alloy includes lithium and at least one metal of Na, K, rb, cs, fr, be, mg, ca, sr, si, sb, pb, in, zn, ba, ra, ge, al, or Sn. Materials capable of doping/dedoping lithium may include, but are not limited to, si, siO x (0<x is less than or equal to 2), si/C compound, si-Q alloy (wherein, Q comprises at least one of alkali metal, alkaline earth metal, 13-16 group element, transition element or rare earth element, but is not Si), sn, snO 2 Sn — C composite, sn — R (where R includes at least one of alkali metal, alkaline earth metal, group 13 to group 16 element, transition element, or rare earth element, but is not Sn), and the like. Q and R are each independently at least one of Mg, ca, sr, ba, ra, sc, Y, ti, zr, hf, rf, V, nb, ta, db, cr, mo, W, sg, tc, re, bh, fe, pb, ru, os, hs, rh, ir, pd, pt, cu, ag, au, zn, cd, B, al, ga, sn, in, tl, ge, P, as, sb, bi, S, se, te, or Po. The transition metal oxide may include, but is not limited to, vanadium oxide and/or lithium vanadium oxide.
In the present application, the negative electrode material layer may further include a conductive agent, and the conductive agent is not particularly limited as long as the object of the present application can be achieved, and may include, for example, but is not limited to, at least one of the above-described conductive agents.
In the present application, the negative electrode material layer may further include a negative electrode binder, and the present application is not particularly limited as long as the purpose of the present application can be achieved, and for example, at least one of vinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, ethylene oxide-containing polymer, polyvinyl pyrrolidone, polyurethane, polytetrafluoroethylene, polyethylene, polypropylene, styrene-butadiene rubber, acryl-styrene-butadiene rubber, epoxy resin, or nylon may be included, but is not limited thereto.
Optionally, the negative electrode may further include a conductive layer between the negative electrode current collector and the negative electrode material layer. The composition of the conductive layer is not particularly limited in the present application and may be a conductive layer commonly used in the art, and the conductive layer may include, but is not limited to, the above-mentioned conductive agent and the above-mentioned negative electrode binder.
The electrochemical device further comprises a diaphragm for separating the positive electrode from the negative electrode, preventing short circuit inside the lithium ion battery, allowing electrolyte ions to freely pass through, and completing the electrochemical charging and discharging process. The separator in the present application is not particularly limited as long as the object of the present application can be achieved. For example, at least one of a Polyolefin (PO) separator mainly composed of Polyethylene (PE) and polypropylene (PP), a polyester film (for example, a polyethylene terephthalate (PET) film), a cellulose film, a polyimide film (PI), a polyamide film (PA), spandex, an aramid film, a woven film, a nonwoven film (nonwoven fabric), a microporous film, a composite film, a separator paper, a roll film, a spun film, and the like. For example, the separator may include a substrate layer and a surface treatment layer. The substrate layer may be a non-woven fabric, a film or a composite film having a porous structure, and the material of the substrate layer may include at least one of polyethylene, polypropylene, polyethylene terephthalate, polyimide, and the like. Optionally, a polypropylene porous film, a polyethylene porous film, a polypropylene nonwoven fabric, a polyethylene nonwoven fabric, or a polypropylene-polyethylene-polypropylene porous composite film may be used. Optionally, a surface treatment layer is disposed on at least one surface of the substrate layer, and the surface treatment layer may be a polymer layer or an inorganic layer, or a layer formed by mixing a polymer and an inorganic substance. For example, the inorganic layer includes inorganic particles and a binder, and the inorganic particles are not particularly limited and may be, for example, at least one selected from 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, barium sulfate, or the like. The binder is not particularly limited, and may be, for example, at least one selected from polyvinylidene fluoride, a copolymer of vinylidene fluoride-hexafluoropropylene, polyamide, polyacrylonitrile, polyacrylate, polyacrylic acid, polyacrylate, polyvinylpyrrolidone, polyvinyl ether, polymethyl methacrylate, polytetrafluoroethylene, or polyhexafluoropropylene. The polymer layer contains a polymer, and the material of the polymer comprises at least one of polyamide, polyacrylonitrile, acrylate polymer, polyacrylic acid, polyacrylate, polyvinylpyrrolidone, polyvinyl ether, polyvinylidene fluoride, poly (vinylidene fluoride-hexafluoropropylene), and the like.
The electrochemical device of the present application is not particularly limited, and may include any device in which electrochemical reactions occur. In some embodiments, the electrochemical device may include, but is not limited to: a lithium metal secondary battery, a lithium ion secondary battery (lithium ion battery), a lithium polymer secondary battery, a lithium ion polymer secondary battery, or the like.
The preparation process of the electrochemical device is well known to those skilled in the art, and the present application is not particularly limited, and for example, may include, but is not limited to, the following steps: stacking the anode, the diaphragm and the cathode in sequence, winding and folding the anode, the diaphragm and the cathode according to needs to obtain an electrode assembly with a winding structure, putting the electrode assembly into a packaging shell, injecting electrolyte into the packaging shell and sealing the packaging shell to obtain the electrochemical device; or, the positive electrode, the separator and the negative electrode are sequentially stacked, then four corners of the entire lamination are fixed with an adhesive tape to obtain an electrode assembly of the lamination, the electrode assembly is placed in a packaging case, and an electrolyte is injected into the packaging case and sealed to obtain the electrochemical device. In addition, an overcurrent prevention element, a guide plate, or the like may be placed in the package case as necessary to prevent a pressure rise and overcharge/discharge inside the electrochemical device.
In a third aspect, the present application provides an electronic device comprising an electrochemical device as described in the second aspect of the present application. The electronic device has good cycle performance and high-temperature storage performance.
The electronic device of the present application is not particularly limited, and may include, but is not limited to, the following categories: notebook computers, pen-input computers, mobile computers, electronic book players, cellular phones, portable facsimile machines, portable copiers, portable printers, head-mounted stereo headphones, video recorders, liquid crystal televisions, portable cleaners, portable CD players, mini-discs, transceivers, electronic notebooks, calculators, memory cards, portable recorders, radios, backup power supplies, motors, automobiles, motorcycles, mopeds, bicycles, lighting equipment, toys, game machines, clocks, electric tools, flashlights, cameras, large household batteries, and lithium ion capacitors.
An electrolyte, an electrochemical device and an electronic device including the same are provided, wherein the electrolyte includes a compound of formula (I-A). The electrolyte comprising the compound of the formula (I-A) is applied to an electrochemical device, so that a stable anode solid interface film can be formed on the surface of a positive electrode of the electrochemical device, and a stable cathode solid interface film can be formed on the surface of a negative electrode of the electrochemical device, and the cycle performance and the high-temperature storage performance of the electrochemical device are effectively improved. An electronic device comprising the electrochemical device also has good high-temperature storage properties and cycle properties.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is further described in detail below with reference to embodiments. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other technical solutions obtained by a person of ordinary skill in the art based on the embodiments in the present application belong to the scope of protection of the present application.
Examples
Hereinafter, embodiments of the present application will be described in more detail with reference to examples and comparative examples. Various tests and evaluations were carried out according to the following methods.
Examples 1 to 1
< preparation of Positive electrode >
The positive electrode active material NCM811 (LiNi) 0.8 Mn 0.1 Co 0.1 O 2 ) Mixing acetylene black serving as a conductive agent and polyvinylidene fluoride serving as a binder according to a mass ratio of 96. And uniformly coating the positive electrode slurry on one surface of an aluminum foil of a positive electrode current collector with the thickness of 12 mu m, and drying the aluminum foil at 120 ℃ for 1h to obtain the positive electrode with the single surface coated with the positive electrode material layer. And repeating the steps on the other surface of the aluminum foil to obtain the anode with the anode material layer coated on the two surfaces. Then the anode is dried for 1h under the vacuum condition of 120 ℃ after cold pressing, cutting and cutting, the specification of 74mm multiplied by 867mm is obtained, and the compaction density of the anode is 3.50g/cm 3 。
< preparation of negative electrode >
Mixing a negative electrode active material graphite, a binder styrene butadiene rubber and a thickener carboxymethylcellulose sodium (CMC) according to a mass ratio of 97.4. And uniformly coating the negative electrode slurry on one surface of a copper foil of a negative electrode current collector with the thickness of 12 mu m, and drying the copper foil at 120 ℃ to obtain the negative electrode with the coating thickness of 130 mu m and the single surface coated with the negative electrode material layer. And repeating the steps on the other surface of the aluminum foil to obtain the cathode with the cathode material layer coated on the two surfaces. Then the mixture is dried for 1h under the vacuum condition of 120 ℃ after cold pressing, cutting into pieces and slitting, and the negative electrode with the specification of 76mm multiplied by 851mm is obtained, and the compaction density of the negative electrode is 1.80g/cm 3 。
< preparation of electrolyte solution >
At water content<In a 10ppm argon atmosphere glove box, EC, PC, DEC were mixed in a mass ratio of 30Adding a third lithium salt lithium hexafluorophosphate (LiPF) into the organic solvent 6 ) And a compound (I-1) of formula (I-A), to obtain an electrolyte. Wherein, liPF 6 Is 1mol/L, based on the mass of the electrolyte, the mass percentage content W of the compound of formula (I-A) I 0.1%, the balance being a third lithium salt and an organic solvent.
< preparation of separator >
Alumina was mixed with polyvinylidene fluoride in a mass ratio of 90. The ceramic slurry was then uniformly coated on one side of a porous substrate (polyethylene, thickness 5 μm, porosity 39%) by a gravure coating method, and subjected to a drying treatment to obtain a two-layer structure of a ceramic coating layer and the porous substrate, the ceramic coating layer having a thickness of 3 μm.
Polyvinylidene fluoride (PVDF) was mixed with polyacrylate in a mass ratio of 96. Then respectively and uniformly coating the polymer slurry on two surfaces of the double-layer structure of the ceramic coating and the porous substrate by adopting a micro-concave coating method, and drying to obtain the diaphragm, wherein the thickness of a single-layer coating formed by the polymer slurry is 2 mg/(50 multiplied by 100 mm) 2 )。
< preparation of lithium ion Battery >
And (3) stacking the prepared positive electrode, the diaphragm and the negative electrode in sequence, enabling the diaphragm to be positioned between the positive electrode and the negative electrode to play a role in isolation, and winding to obtain the electrode assembly. And (3) placing the electrode assembly in an aluminum-plastic film packaging bag, drying, injecting electrolyte, and performing vacuum packaging, standing, formation, degassing, edge cutting and other processes to obtain the lithium ion battery. The upper limit voltage of formation is 4.15V, the formation temperature is 70 ℃, and the formation standing time is 2h.
Examples 1-2 to examples 1-14
Except that the kind and mass% W of the compound of formula (I-A) were adjusted as shown in Table 1 I The procedure of example 1-1 was repeated except that the content of the organic solvent was changed.
Example 2-1 to example 2-7
The procedure was repeated as in example 1-1 except that the compound of the formula (II-A) was further added to < preparation of electrolyte solution > in accordance with the species and mass% shown in Table 2, and the content of the organic solvent was changed.
Example 3-1 to example 3-4
The procedure was repeated as in example 1-1, except that the first lithium salt was further added in the amount shown in Table 3 and the content of the organic solvent was changed as shown in < preparation of electrolyte solution >.
Example 4-1 to example 4-8
The procedure of example 1-1 was repeated, except that in < preparation of electrolyte solution > the sulfur-oxygen double bond compound was further added in accordance with the species and mass% shown in Table 4, and the content of the organic solvent was changed.
Example 5-1 to example 5-2
The procedure of example 1-1 was repeated, except that the contents of the compound of the formula (II-A), the first lithium salt, the thiooxy double bond compound and the organic solvent were further optionally changed in the following manner in the preparation of an electrolyte solution, in accordance with the kind and the content by mass shown in Table 5.
Example 6-1
< preparation of Positive electrode >
Mixing anode active material LCO (molecular formula is LiCoO) 2 ) The conductive carbon black, the conductive slurry and the binding agent polyvinylidene fluoride are fully stirred and mixed in a proper amount of NMP solvent according to the weight ratio of 97.9. And uniformly coating the positive electrode slurry on one surface of an aluminum foil of a positive electrode current collector with the thickness of 12 mu m, and drying the aluminum foil at 120 ℃ for 1h to obtain the positive electrode with the single surface coated with the positive electrode material layer. And repeating the steps on the other surface of the aluminum foil to obtain the anode with the anode material layer coated on the two surfaces. Then the anode is dried for 1h under the vacuum condition of 120 ℃ after cold pressing, cutting into pieces and cutting, and the anode with the specification of 74mm multiplied by 867mm is obtained, and the compaction density of the anode is 4.15g/cm 3 。
< preparation of electrolyte solution >
At water content<In a 10ppm argon atmosphere glove box, EC, PC, DEC, EP, propyl propionate were uniformly mixed at a mass ratio of 20 6 ) And a compound (I-1) of formula (I-A), to obtain an electrolyte. Wherein, liPF 6 Is 1mol/L, based on the mass of the electrolyte, the mass percentage content W of the compound of formula (I-A) I 0.1%, the balance being a third lithium salt and an organic solvent.
< preparation of negative electrode >, < preparation of separator > and < preparation of lithium ion battery > were the same as in example 1-1.
Example 6-2 to example 6-8
The procedure was repeated in the same manner as in example 6-1 except that the type and the content by mass of the polynitrile compound shown in Table 6 were changed in < preparation of electrolyte solution >.
Example 7-1 to example 7-7
The procedure was repeated in the same manner as in example 6-1 except that in < preparation of electrolyte solution > cyclic carbonate and chain carbonate were further added in accordance with the species and mass% shown in Table 7, and the content of organic solvent was changed.
Example 8-1 to example 8-6
The procedure was repeated as in example 6-1, except that the second lithium salt was further added in the amount shown in Table 8 and the content of the organic solvent was changed as shown in < preparation of electrolyte solution >.
Example 9-1 to example 9-4
The procedure of example 6-1 was repeated, except that a polynitrile compound, a second lithium salt and a thiooxy double bond compound were further optionally added in the amounts by mass shown in Table 9 in < preparation of electrolyte > and the content of the organic solvent was changed accordingly.
Comparative examples 1 to 2
Except that the kind and mass% W of the compound of formula (I-A) were adjusted as shown in Table 1 I The content of the organic solvent is changedThe procedure of example 1-1 was repeated except for changing the components.
The lithium ion batteries prepared in the above examples and comparative examples were subjected to performance tests according to the following test methods and equipment:
cycle capacity retention rate test:
the lithium ion battery was charged at 25 ℃ at 1C to 4.25V and at 4.25V to 0.05C at a constant voltage. And then discharging to 2.8V by using 4C current, and recording the capacity of the tested lithium ion battery as the first-turn capacity. And taking the charge-discharge process as a cycle, and performing cycle test for 800 circles, wherein the capacity of the lithium ion battery is recorded as the capacity after the cycle. Cycle capacity retention (%) = first-turn capacity/capacity after cycle × 100%.
And (3) testing the high-temperature storage performance:
lithium ion batteries prepared in each of examples and comparative examples in tables 1 to 5 were charged at 25 ℃ to 4.25V at a constant current of 0.5C and then charged at a constant voltage to a current of 0.05C, and the thickness of the lithium ion batteries was measured and designated as d 01 (ii) a The thickness of the lithium ion battery is tested after the lithium ion battery is placed in an oven at 85 ℃ for 6 hours and is recorded as d 1 . Thickness expansion rate (%) of lithium ion battery after 6h of 85 ℃ storage 1 -d 01 )/d 01 ×100％。
The lithium ion batteries prepared in the examples of tables 6 to 9 were charged at 25 ℃ to 4.45V at a constant current of 0.5C and then charged at a constant voltage to a current of 0.05C, and the thickness of the lithium ion batteries was measured and recorded as d 02 Testing the thickness of the lithium ion battery after the lithium ion battery is placed in an oven at 85 ℃ for 24 hours, and marking the thickness as d 2 . Thickness expansion rate (%) of lithium ion battery after storage for 24h at 85% 2 -d 02 )/d 02 X100%. Wherein, the test is stopped when the thickness expansion rate is more than 50%, and the thickness expansion rate "more than 50% in tables 6 to 9 means that the thickness expansion rate is more than 50% when the test time is less than 24h, and the test is stopped.
Testing the floating charge performance:
the lithium ion battery is discharged to 3.0V at 25 ℃ at 0.5C, charged to 4.45V at 0.5C, charged to 0.05C at constant voltage at 4.45V, tested for thickness and noted as d 03 Placing the mixture in a 45 ℃ ovenIn the middle, 4.45V constant voltage charging is carried out for 30 days, the thickness change is monitored, and the thickness is recorded as d 3 Thickness expansion rate (%) of lithium ion battery float charge = (d) 3 -d 03 )/d 03 X 100%, and stopping the test when the thickness expansion rate is more than 50%.
The preparation parameters and performance parameters of the respective examples and comparative examples are shown in tables 1 to 9:
TABLE 1
Figure BDA0003872501210000181
Note: the "\\" in Table 1 indicates no corresponding production or performance parameters. In table 1, "-" indicates that the number of cycles of the lithium ion batteries of comparative example 1 and comparative example 2 in the cycle capacity retention rate test did not reach 800 cycles.
As can be seen from examples 1-1 to examples 1-9 and comparative example 1, the cycle performance and high-temperature storage performance of the lithium ion battery vary depending on the kind of the compound of formula (I-A). Lithium ion batteries containing compounds of formula (I-A) within the scope of the present application have better cycling performance and high temperature storage performance.
The mass percentage content W of the compound of the formula (I-A) I And also generally has an effect on cycle performance and high-temperature storage performance of the lithium ion battery. As can be seen from examples 1-1, 1-10 to 1-14 and comparative example 2, the mass percentage W of the compound of formula (I-A) I The lithium ion battery in the range of the application has better cycle performance and high-temperature storage performance.
TABLE 2
Figure BDA0003872501210000182
Figure BDA0003872501210000191
Note: the "\\" in Table 2 indicates no corresponding production or performance parameters.
The kind and mass percentage content W of the compound of formula (II-A) II And W I /W II The value of (a) also generally has an effect on the cycle performance and high-temperature storage performance of the lithium ion battery. As can be seen from examples 1-1, 2-1 to 2-7, the kind and mass% W of the compound of the formula (II-A) II And W I /W II The lithium ion battery with the value in the range has good cycle performance and high-temperature storage performance.
TABLE 3
Figure BDA0003872501210000192
Note: the "\\" in Table 3 indicates no corresponding production or performance parameters.
The kind and mass percentage content W of the first lithium salt L1 And also generally have an effect on cycle performance and high temperature storage performance of the lithium ion battery. As can be seen from examples 1-1, 3-1 to 3-4, the kind and mass% W of the first lithium salt L1 The lithium ion battery in the range of the application has good cycle performance and high-temperature storage performance.
TABLE 4
Figure BDA0003872501210000193
Note: the "\\" in Table 4 indicates no corresponding production or performance parameters.
Kinds and mass percentage contents W of sulfur-oxygen double bond compounds S And W I /W S The value of (a) also generally has an effect on the cycle performance and high-temperature storage performance of the lithium ion battery. As can be seen from examples 1-1 and 4-1 to 4-8, the sulfur-oxygen double bond compound was present in the same type and in a same amount as W S And W I /W S The lithium ion battery with the value in the range has good cycle performance and high-temperature storage performance.
TABLE 5
Figure BDA0003872501210000201
Note: the "\\" in table 5 indicates no corresponding preparation parameters.
The compound of formula (I-a), optionally in combination with at least two of the compound of formula (II-a), the first lithium salt or the sulfur-oxygen double bond compound, has an effect on the cycle performance and float charge performance of the lithium ion battery. As can be seen from examples 1-1, 5-1 and 5-2, the compound of formula (I-A) has good compatibility and superposability with the compound of formula (II-A), the first lithium salt or the thiooxy-sulfur double bond compound, and the lithium ion batteries obtained by using the compound in combination all have good cycle performance and float charge performance.
TABLE 6
Figure BDA0003872501210000202
Note: the "\\" in Table 6 indicates no corresponding production or performance parameters.
The kind and mass percentage content W of the polynitrile compound D And generally has an impact on the high-temperature storage performance and the float charge performance of the lithium ion battery. As can be seen from examples 6-1 to 6-8, the kinds and mass percentages W of the polynitrile compounds D The lithium ion battery in the range of the application has good high-temperature storage performance and floating charge performance.
TABLE 7
Figure BDA0003872501210000211
Note: the "\\" in Table 7 indicates no corresponding production or performance parameters.
The kind and mass percentage content W of the first non-aqueous organic solvent H The mass ratio of the cyclic carbonate to the chain carbonate and the mass ratio of the cyclic carbonate to the carboxylic ester generally also contribute to the cycle performance and high-temperature storage of the lithium ion batteryPerformance is affected. As can be seen from examples 6-1, 7-1 to 7-7, the kind and mass% W of the first nonaqueous organic solvent H The lithium ion battery with the mass ratio of the cyclic carbonate to the chain carbonate and the mass ratio of the cyclic carbonate to the carboxylic ester within the range has good cycle performance and high-temperature storage performance. As can be seen from examples 7-1 to 7-5, the first nonaqueous organic solvent is contained in an amount W in percentage by mass H The lithium ion battery in the preferable range of the application has better cycle performance.
TABLE 8
Figure BDA0003872501210000212
Figure BDA0003872501210000221
Note: the "\\" in Table 8 indicates no corresponding production or performance parameters.
The kind and mass percentage content W of the second lithium salt L2 And also generally has an effect on the cycle performance, the float charge performance, and the high-temperature storage performance of the lithium ion battery. As can be seen from examples 6-1, 8-1 to 8-6, the kind and mass% W of the second lithium salt L2 The lithium ion battery in the range has good cycle performance, floating charge performance and high-temperature storage performance. Examples 8-1 to 8-6 especially have better cycle performance than example 6-1.
TABLE 9
Figure BDA0003872501210000222
Note: the "\\" in Table 9 indicates no corresponding production or performance parameters.
The compound of formula (I-a) is optionally used in combination with at least two of a sulfur-oxygen double bond compound, a polynitrile compound, or a second lithium salt, and affects cycle performance, float charge performance, and high temperature storage performance of a lithium ion battery. As can be seen from examples 6-1, 9-1 to 9-4, the compound of formula (I-A) has good compatibility and superimposability with a thioredoxin bond compound, a polynitrile compound or a second lithium salt, and the lithium ion batteries obtained by using the compounds in combination all have good high-temperature storage performance and floating charge performance.
The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims (24)

1. An electrolyte comprising a compound of formula (I-a):
Figure FDA0003872501200000011
wherein the content of the first and second substances,
A 1 selected from the subunits of formula (I-B), formula (I-C) or formula (I-D):
Figure FDA0003872501200000012
x and Y are each independently selected from a subunit of formula (I-E), a subunit of formula (I-F), a subunit of formula (I-G), or a subunit of formula (I-H):
Figure FDA0003872501200000013
Figure FDA0003872501200000014
represents a binding site to an adjacent atom;
R 12 and R 17 Each independently selected from substituted or unsubstituted C 1 To C 10 Alkyl, substituted or unsubstituted C 2 To C 10 Alkenyl of (a), substituted or unsubstituted C 2 To C 10 Alkynyl, substituted or unsubstituted C 6 To C 10 Aryl, substituted or unsubstituted C 3 To C 10 Alicyclic hydrocarbon group of (1), substituted or unsubstituted C 1 To C 10 Lipoheterocyclic group of (A), substituted or unsubstituted C 1 To C 10 When substituted, each substituent is independently selected from halogen atoms;
R 11 、R 13 、R 14 、R 15 、R 16 、R 18 and R 19 Each independently selected from the group consisting of a single bond, substituted or unsubstituted C 1 To C 10 Alkylene, substituted or unsubstituted C 2 To C 10 Alkenylene group of (1), substituted or unsubstituted C 2 To C 10 Alkynylene of (a), substituted or unsubstituted C 6 To C 10 Arylene of (a), substituted or unsubstituted C 3 To C 10 Alicyclic hydrocarbon group of (a), substituted or unsubstituted C 1 To C 10 A substituted or unsubstituted C 1 To C 10 When substituted, each substituent is independently selected from halogen atoms;
the heteroatoms in the aliphatic heterocyclic group, the aromatic heterocyclic group, the alkenylene heterocyclic group, and the arylene heterocyclic group each independently comprise N, S or O.
2. The electrolyte of claim 1, wherein the compound of formula (I-a) comprises at least one of the following compounds (I-1) to (I-38):
Figure FDA0003872501200000021
3. the electrolyte of claim 1, wherein the compound of formula (I-a) is present in an amount W based on the mass of the electrolyte I Is 0.01 to 5 percent.
4. The electrolyte of claim 3, wherein the electrolyte further comprises a compound of formula (II-A):
Figure FDA0003872501200000031
wherein the content of the first and second substances,
R 21 and R 22 Each independently selected from substituted or unsubstituted C 1 To C 5 Alkyl, substituted or unsubstituted C 2 To C 5 Alkenyl of (a), substituted or unsubstituted C 2 To C 5 When substituted, each substituent is independently selected from a halogen atom or a methyl group, R 21 And R 22 A closed loop structure may be constructed.
5. The electrolyte of claim 4, wherein the compound of formula (II-A) comprises at least one of the following compounds (II-1) to (II-12):
Figure FDA0003872501200000032
6. the electrolyte of claim 4, wherein the electrolyte meets at least one of the following (a) or (b):
(a) The mass percentage content W of the compound of the formula (II-A) based on the mass of the electrolyte II From 0.05% to 3%;
(b) The mass percentage content W of the compound of the formula (I-A) based on the mass of the electrolyte I And the mass percentage content W of the compound of the formula (II-A) II Satisfies the following conditions: w is more than 0 I /W II ≤10。
7. The electrolyte of claim 1, wherein the electrolyte further comprises a first lithium salt comprising at least one of lithium difluorophosphate, lithium difluorobis-oxalato-phosphate, or lithium tetrafluorooxalato-phosphate.
8. The electrolyte of claim 7, wherein the mass percent W of the first lithium salt is based on the mass of the electrolyte L1 Is 0.1% to 1%.
9. The electrolyte of claim 3, wherein the electrolyte further comprises a sulfur-oxygen double bond compound comprising a compound of formula (III-A):
Figure FDA0003872501200000041
wherein the content of the first and second substances,
A 3 any one selected from the group consisting of the subunit of formula (III-B), the subunit of formula (III-C), the subunit of formula (III-D), the subunit of formula (III-E), the subunit of formula (III-F), the subunit of formula (III-G), the subunit of formula (III-H), and the subunit of formula (III-I):
Figure FDA0003872501200000042
Figure FDA0003872501200000043
represents a binding site to an adjacent atom;
R 31 and R 32 Each independently selected from substituted or unsubstituted C 1 To C 5 Alkyl, substituted or unsubstituted C 2 To C 10 Alkenyl of (a), substituted or unsubstituted C 2 To C 10 Alkynyl, substituted or unsubstituted C 3 To C 10 An alicyclic group of (A), substituted or unsubstituted C 6 To C 10 Aryl, substituted or unsubstituted C 1 To C 6 Lipoheterocyclic group of (A), substituted or unsubstituted C 1 To C 6 Aryl heterocyclic group of (1), substituted or unsubstituted C 1 To C 3 When substituted, each substituent is independently selected from halogen atom, C 1 To C 3 Alkyl of (C) 2 To C 3 Alkenyl or C of 2 To C 3 Alkynyl of R 31 And R 32 A closed loop structure can be formed;
the heteroatoms in the aliphatic heterocyclic group and the aromatic heterocyclic group each independently comprise N, S or O.
10. The electrolyte of claim 9, wherein the compound of formula (III-a) comprises at least one of the following compounds (III-1) to (III-53):
Figure FDA0003872501200000044
Figure FDA0003872501200000051
11. the electrolyte of claim 9, wherein the compound of formula (III-a) comprises at least one of the following compounds:
Figure FDA0003872501200000052
12. the electrolyte of claim 9, wherein the electrolyte satisfies at least one of the following (c) or (d):
(c) Based on the mass of the electrolyte, the mass percentage content W of the sulfur-oxygen double bond compound S From 0.01% to 10%;
(d) The mass percentage content W of the compound of the formula (I-A) based on the mass of the electrolyte I And the sulfur-oxygen double bond compound is W S Satisfies the following conditions: w is more than 0 I /W S ≤1。
13. The electrolyte of claim 1, wherein the electrolyte further comprises a polynitrile compound including at least one of the following compounds (i-1) to (i-16):
Figure FDA0003872501200000061
14. the electrolyte of claim 13, wherein the polynitrile compound is present in a mass percent W based on the mass of the electrolyte D Is 0.3 to 10 percent.
15. The electrolyte of claim 1, further comprising a first non-aqueous organic solvent comprising at least one of a cyclic carbonate, a chain carbonate, or a carboxylic ester.
16. The electrolyte of claim 15, wherein the cyclic carbonate comprises Sup>A compound of formulSup>A (IV-Sup>A):
Figure FDA0003872501200000062
wherein R is 4 Selected from substituted or unsubstituted C 1 To C 6 Alkylene, substituted or unsubstituted C 2 To C 6 Alkenylene, when substituted, each substituent is independently selected from halogen atom, C 1 To C 6 Alkyl or C 2 To C 6 An alkenyl group.
17. The electrolyte of claim 16, wherein the compound of formulSup>A (IV-Sup>A) comprises at least one of the following compounds (IV-1) to (IV-12):
Figure FDA0003872501200000063
Figure FDA0003872501200000071
18. the electrolyte of claim 15,
the chain carbonate comprises at least one of dimethyl carbonate, methylethyl carbonate, fluoromethyl methyl carbonate, bis (fluoromethyl) carbonate, difluoromethyl methyl carbonate, ethyl (fluoromethyl) carbonate, difluoromethyl ethyl carbonate, 2-fluoroethyl methyl carbonate, 2-fluoroethyl (fluoromethyl) carbonate, 2,2-difluoroethyl methyl carbonate, 2,2-difluoroethyl carbonate, 2,2,2-trifluoroethyl ethyl carbonate, ethyl 2-fluoroethyl carbonate, bis (2-fluoroethyl) carbonate, 2,2-difluoroethyl (2-fluoroethyl) carbonate, bis (2,2-difluoroethyl) carbonate, bis (2,2,2-trifluoroethyl) carbonate, methylpropyl carbonate or ethylpropyl carbonate;
the carboxylic acid ester comprises at least one of methyl formate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, 2,2-difluoroethyl acetate or 2,2-difluoroethyl acetate.
19. The electrolyte of claim 15, wherein the electrolyte satisfies at least one of the following (e) to (g):
(e) The mass percentage content W of the cyclic carbonate based on the mass of the electrolyte H From 0.01% to 30%;
(f) The mass ratio of the cyclic carbonate to the chain carbonate is (10-60) to 40;
(g) The mass ratio of the cyclic carbonate to the carboxylic ester is (10-60) to (20-60).
20. The electrolyte of claim 3, wherein the electrolyte further comprises Sup>A second lithium salt comprising Sup>A compound of formulSup>A (V-A):
Figure FDA0003872501200000072
wherein the content of the first and second substances,
A 51 、A 52 、A 53 and A 54 Each independently selected from a halogen atom, a group of formula (V-B), a group of formula (V-C) or a group of formula (V-D), A 51 、A 52 、A 53 And A 54 Wherein two adjacent groups may form a closed ring structure:
Figure FDA0003872501200000073
Figure FDA0003872501200000074
represents a binding site to an adjacent atom;
o in the two binding sites of the group of formula (V-C) is linked to B, k is 0 or 1;
R 51 and R 53 Each independently selected from substituted or unsubstituted C 1 To C 6 Alkyl, substituted or unsubstituted C 2 To C 6 When substituted, each substituent is independently selected from halogen atoms;
R 52 selected from substituted or unsubstituted C 1 To C 6 Alkylene of (a), substituted or unsubstituted C 2 To C 6 When substituted, each substituent is independently selected from halogen atoms.
21. The electrolyte of claim 20, wherein the compound of formulSup>A (V-Sup>A) comprises at least one of lithium tetrafluoroborate, lithium dioxalate borate, or lithium difluorooxalate borate.
22. According to the rightThe electrolyte of claim 20, wherein the second lithium salt comprises W, in mass percent, based on the mass of the electrolyte L2 Is 0.1% to 2%.
23. An electrochemical device comprising the electrolyte of any one of claims 1 to 22.
24. An electronic device comprising the electrochemical device of claim 23.
CN202180026202.1A 2021-12-28 2021-12-28 Electrolyte, electrochemical device containing electrolyte and electronic device Pending CN115443569A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2021/142076 WO2023122956A1 (en) 2021-12-28 2021-12-28 Electrolyte, electrochemical apparatus containing same and electronic apparatus

Publications (1)

Publication Number Publication Date
CN115443569A true CN115443569A (en) 2022-12-06

Family

ID=84240900

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202180026202.1A Pending CN115443569A (en) 2021-12-28 2021-12-28 Electrolyte, electrochemical device containing electrolyte and electronic device

Country Status (2)

Country Link
CN (1) CN115443569A (en)
WO (1) WO2023122956A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116544514A (en) * 2023-07-07 2023-08-04 宁德新能源科技有限公司 Electrochemical device and electronic device

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003208920A (en) * 2002-01-16 2003-07-25 Mitsubishi Chemicals Corp Nonaqueous electrolytic solution and lithium secondary battery using the same
CN102119463A (en) * 2008-08-04 2011-07-06 宇部兴产株式会社 Nonaqueous electrolyte and lithium cell using the same
JP2012104439A (en) * 2010-11-12 2012-05-31 Mitsubishi Chemicals Corp Nonaqueous electrolyte and nonaqueous electrolyte secondary battery including the same
EP3557678A1 (en) * 2018-04-20 2019-10-23 Contemporary Amperex Technology Co., Limited Electrolyte and battery
CN112119530A (en) * 2019-12-24 2020-12-22 宁德新能源科技有限公司 Electrolyte solution, and electrochemical device and electronic device using same
CN112599854A (en) * 2020-12-11 2021-04-02 宁德新能源科技有限公司 Electrolyte solution, electrochemical device, and electronic device
CN113366687A (en) * 2020-09-23 2021-09-07 宁德新能源科技有限公司 Electrolyte solution, electrochemical device, and electronic device
CN113711412A (en) * 2020-12-30 2021-11-26 宁德新能源科技有限公司 Electrolyte solution, electrochemical device, and electronic device

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003208920A (en) * 2002-01-16 2003-07-25 Mitsubishi Chemicals Corp Nonaqueous electrolytic solution and lithium secondary battery using the same
CN102119463A (en) * 2008-08-04 2011-07-06 宇部兴产株式会社 Nonaqueous electrolyte and lithium cell using the same
JP2012104439A (en) * 2010-11-12 2012-05-31 Mitsubishi Chemicals Corp Nonaqueous electrolyte and nonaqueous electrolyte secondary battery including the same
EP3557678A1 (en) * 2018-04-20 2019-10-23 Contemporary Amperex Technology Co., Limited Electrolyte and battery
CN112119530A (en) * 2019-12-24 2020-12-22 宁德新能源科技有限公司 Electrolyte solution, and electrochemical device and electronic device using same
CN113366687A (en) * 2020-09-23 2021-09-07 宁德新能源科技有限公司 Electrolyte solution, electrochemical device, and electronic device
CN112599854A (en) * 2020-12-11 2021-04-02 宁德新能源科技有限公司 Electrolyte solution, electrochemical device, and electronic device
CN113711412A (en) * 2020-12-30 2021-11-26 宁德新能源科技有限公司 Electrolyte solution, electrochemical device, and electronic device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116544514A (en) * 2023-07-07 2023-08-04 宁德新能源科技有限公司 Electrochemical device and electronic device
CN116544514B (en) * 2023-07-07 2024-03-08 宁德新能源科技有限公司 Electrochemical device and electronic device

Also Published As

Publication number Publication date
WO2023122956A1 (en) 2023-07-06

Similar Documents

Publication Publication Date Title
CN111525191B (en) Electrolyte and electrochemical device
CN113437366B (en) Electrolyte and electrochemical device
CN113809399B (en) Electrolyte, electrochemical device and electronic device comprising same
CN110994018B (en) Electrolyte and electrochemical device
CN113906606B (en) Electrolyte, electrochemical device, and electronic device
CN112400249A (en) Electrolyte and electrochemical device
CN109830749B (en) Electrolyte and electrochemical device
CN111342137A (en) Electrolyte and electrochemical device
CN113366687B (en) Electrolyte, electrochemical device, and electronic device
JP7383716B2 (en) Electrolytes, electrochemical devices and electronic devices
CN113711412B (en) Electrolyte, electrochemical device, and electronic device
CN115443569A (en) Electrolyte, electrochemical device containing electrolyte and electronic device
CN111971845A (en) Electrolyte and electrochemical device
CN110854432A (en) Electrolyte solution, and electrochemical device and electronic device using same
CN114094191B (en) Electrolyte, electrochemical device and electronic device comprising same
WO2023123464A1 (en) Electrolyte solution, electrochemical device containing same, and electronic device
CN114400375A (en) Electrolyte solution, electrochemical device, and electronic device
CN114221034A (en) Electrochemical device and electronic device comprising same
CN112368872A (en) Electrolyte and electrochemical device
CN112670580B (en) Electrolyte solution, electrochemical device, and electronic device
CN114094188B (en) Electrochemical device and electronic device comprising same
CN116053461B (en) Electrochemical device and electronic device including the same
CN117175013A (en) Electrolyte, electrochemical device using same and electronic device
CN114335726A (en) Non-aqueous electrolyte and lithium ion battery containing same
JP2024516270A (en) Nonaqueous electrolyte for lithium secondary battery and lithium secondary battery containing same

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination