CN116417677A - Secondary battery and device - Google Patents

Secondary battery and device Download PDF

Info

Publication number
CN116417677A
CN116417677A CN202310678976.3A CN202310678976A CN116417677A CN 116417677 A CN116417677 A CN 116417677A CN 202310678976 A CN202310678976 A CN 202310678976A CN 116417677 A CN116417677 A CN 116417677A
Authority
CN
China
Prior art keywords
formula
secondary battery
alkyl
positive electrode
nitrogen
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
CN202310678976.3A
Other languages
Chinese (zh)
Inventor
李思远
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.)
Weilai Battery Technology Anhui Co ltd
Original Assignee
Weilai Battery Technology Anhui Co 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 Weilai Battery Technology Anhui Co ltd filed Critical Weilai Battery Technology Anhui Co ltd
Priority to CN202310678976.3A priority Critical patent/CN116417677A/en
Publication of CN116417677A publication Critical patent/CN116417677A/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
    • H01M10/056—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
    • 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
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • 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)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Inorganic Chemistry (AREA)
  • Secondary Cells (AREA)

Abstract

The present application relates to a secondary battery and an apparatus. The secondary battery of the present application comprises a positive electrode, a negative electrode, and an electrolyte, wherein the electrolyte comprises a sulfur-containing additive and a nitrogen-containing additive; the positive electrode comprises a positive electrode active material layer and a solid electrolyte interface film positioned on the surface of the positive electrode active material layer, wherein the solid electrolyte interface film is tested by adopting an X-ray photoelectron spectrometer, the mass percentage of sulfur element in the solid electrolyte interface film is S, and the mass percentage of nitrogen element is N, wherein 2S-N is more than 0 and less than or equal to 1.5. The secondary battery improves the cycle performance, the storage performance and the safety performance at high temperature of the secondary battery while taking the low impedance into consideration by controlling the contents of the sulfur element and the nitrogen element in the solid electrolyte interface film formed on the surface of the positive electrode active material layer.

Description

Secondary battery and device
Technical Field
The present application relates to the field of energy storage. In particular, the present application relates to a secondary battery and an apparatus.
Background
The lithium ion battery rapidly occupies the 3C fields of mobile phones, notebook computers and the like by virtue of numerous advantages, and even becomes a key component of various electric automobiles. In order to further meet the demands of people for higher performance of batteries, development of lithium ion batteries with low price, high energy density, high safety and long service life is pursued by many developers.
However, in the battery cycle process, the positive and negative electrodes of the battery are easy to react with the electrolyte, so that on one hand, the capacity of the battery is reduced, the cycle life is greatly reduced, and on the other hand, the gas is generated, the volume of the battery is expanded, and the safety of the battery is reduced. As the battery operating temperature increases, the side reactions become more severe and the problem of gas production becomes more serious.
Disclosure of Invention
In view of the problems of the current lithium ion batteries, the present application provides a secondary battery and a related device. The secondary battery of the application improves the cycle performance, the storage performance and the safety performance at high temperature of the secondary battery while taking low impedance into consideration by controlling the contents of sulfur element and nitrogen element in the solid electrolyte interface film (CEI film) formed on the surface of the positive electrode active material layer.
A first aspect of the present application provides a secondary battery comprising a positive electrode, a negative electrode, and an electrolyte, wherein the electrolyte comprises a sulfur-containing additive and a nitrogen-containing additive; the positive electrode comprises a positive electrode active material layer and a solid electrolyte interface film positioned on the surface of the positive electrode active material layer, wherein the solid electrolyte interface film is tested by adopting an X-ray photoelectron spectrometer, the mass percentage of sulfur element in the solid electrolyte interface film is S, and the mass percentage of nitrogen element is N, wherein 2S-N is more than 0 and less than or equal to 1.5.
A second aspect of the present application provides an apparatus comprising the secondary battery of the first aspect.
The beneficial effects of this application are:
according to the secondary battery, the content of sulfur and nitrogen in the solid electrolyte interface film (CEI film) formed on the surface of the positive electrode active material layer is controlled, so that the CEI film is more compact and stable, contact between electrolyte and the positive electrode active material can be effectively inhibited to continuously decompose, gas production is inhibited, and further the cycle performance and safety performance of the secondary battery, particularly the cycle performance and storage performance at high temperature, are improved, meanwhile, the CEI film with the content of the specific sulfur and nitrogen being matched has high lithium ion conductivity, interface impedance can be reduced, and the impedance of the secondary battery is further reduced.
Detailed Description
For simplicity, this application discloses only a few numerical ranges specifically. However, any lower limit may be combined with any upper limit to form a range not explicitly recited; and any lower limit may be combined with any other lower limit to form a range not explicitly recited, and any upper limit may be combined with any other upper limit to form a range not explicitly recited. Furthermore, each separately disclosed point or individual value may itself be combined as a lower limit or upper limit with any other point or individual value or with other lower limit or upper limit to form a range not explicitly recited.
Unless otherwise indicated, terms used in the present application have well-known meanings commonly understood by those skilled in the art. Unless otherwise indicated, the numerical values of the parameters set forth in this application may be measured by various measurement methods commonly used in the art (e.g., may be tested according to the methods set forth in the examples of this application).
The list of items to which the term "at least one of" or other similar terms is attached may mean any combination of the listed items. For example, if items a and B are listed, the phrase "at least one of a and B" means only a; only B; or A and B. In another example, if items A, B and C are listed, then the phrase "at least one of A, B and C" means only a; or only B; only C; a and B (excluding C); a and C (excluding B); b and C (excluding A); or A, B and C. Item a may comprise a single component or multiple components. Item B may comprise a single component or multiple components. Item C may comprise a single component or multiple components.
The present application is further described below in conjunction with the detailed description. It should be understood that these specific embodiments are presented by way of example only and are not intended to limit the scope of the present application.
1. Secondary battery
The secondary battery comprises a positive electrode, a negative electrode and an electrolyte, wherein the electrolyte comprises a sulfur-containing additive and a nitrogen-containing additive; the positive electrode comprises a positive electrode active material layer and a solid electrolyte interface film positioned on the surface of the positive electrode active material layer, wherein the solid electrolyte interface film is tested by adopting an X-ray photoelectron spectrometer, the mass percentage of sulfur element in the solid electrolyte interface film is S, and the mass percentage of nitrogen element is N, wherein 2S-N is more than 0 and less than or equal to 1.5. The sulfur element from the sulfur-containing additive in the CEI of the positive electrode solid electrolyte interface film can improve the high-temperature stability of the CEI film, thereby being beneficial to improving the high-temperature storage performance and the high-temperature cycle performance of the positive electrode; however, since sulfur is a poor conductor of lithium ions and electrons, when the content of sulfur is large, the kinetic performance of the electrode is affected, and the electrochemical performance of the battery is further affected. The nitrogen element from the nitrogen-containing additive in the CEI film can improve the conductivity of lithium ions and electrons, but the CEI film formed on the surface of the positive electrode active material layer is not dense and stable enough, thereby affecting the cycle performance and storage performance of the battery. The inventor of the application finds through research that the content of sulfur element and nitrogen element is controlled in the above range, on one hand, the CEI film is more compact and stable, can effectively inhibit the electrolyte from being contacted with the positive electrode active material to be continuously decomposed, and inhibit gas production, so that the cycle performance and the safety performance of the secondary battery, particularly the cycle performance and the storage performance at high temperature, are improved, on the other hand, the sulfur element and the nitrogen element in the CEI film have good synergistic effect, the kinetic characteristic of lithium ion transmission at an interface can be improved, and the performance of the secondary battery is greatly improved.
In some embodiments, 2S-N is 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1, 1.05, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, or a range of any two of these values. In some embodiments, 0< 2S-N.ltoreq.1.
In some embodiments, 0.2.ltoreq.S.ltoreq.10. In some embodiments, S is 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.2, 3.5, 3.8, 4, 4.2, 4.5, 4.8, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, or a range of any two of these values. In some embodiments, 0.5.ltoreq.S.ltoreq.5. In some embodiments, 1.ltoreq.S.ltoreq.3.
In some embodiments, 1.ltoreq.N.ltoreq.12. In some embodiments, N is 1, 1.3, 1.5, 1.7, 2, 2.3, 2.5, 2.7, 3, 3.3, 3.5, 3.7, 4, 4.3, 4.5, 4.8, 5, 5.3, 5.5, 5.8, 6.3, 6.5, 6.8, 7, 7.3, 7.5, 7.8, 8, 8.3, 8.5, 8.8, 9, 9.3, 9.5, 9.8, 10, 10.3, 10.5, 10.8, 11, 11.3, 11.5, 11.8, 12 or a range of any two of these values. In some embodiments, 2.ltoreq.N.ltoreq.10. In some embodiments, 2.ltoreq.N.ltoreq.6.
In the application, the tortuosity of the positive pole piece is tau. Tortuosity is a parameter reflecting the degree of tortuosity of a path from one end to the other end of a cell in a porous medium relative to a straight line, i.e., the ratio of the actual flow path length to the straight line distance between the ends of the flow path. In the electrode structure, electrolyte fully infiltrates into pores, and lithium ions are required to be transferred along the pore canal through the electrolyte, so that the tortuosity of the electrode has important influence on the lithium ion conductivity and the electrolyte diffusion in the electrode, and has important significance in constructing the relationship between the performance of the battery and the interface composition and the structural characteristics of the electrode. In this application, tortuosity can be adjusted by conventional means in the art, such as controlling pole piece roll pressure, roll temperature, roll speed and number of rolls, depending on the active material characteristics selected.
In some embodiments, 0< NS-2τ <8. When the NS-2 tau value is too large, the content of nitrogen and sulfur in the CEI film is correspondingly too high, or the tortuosity of the positive electrode plate is too small, so that the reaction between the electrolyte and the electrode is increased, the electrolyte is consumed, the cycle life is reduced, and the gas production of the battery is increased. When the NS-2τ value is too small, the content of nitrogen and sulfur in the CEI film is correspondingly too low, or the tortuosity of the positive electrode plate is larger, the wettability of the positive electrode electrolyte is reduced, and the secondary battery is polarized in the circulation process, the capacity is reduced, and the circulation performance of the secondary battery is further influenced.
In some embodiments, NS-2τ is 0.2, 0.5, 0.8, 1, 1.2, 1.5, 1.8, 2, 2.2, 2.5, 2.8, 3, 3.2, 3.5, 3.8, 4, 4.2, 4.5, 4.8, 5, 5.2, 5.4, 5.6, 5.8, 6, 6.5, 7, 7.5, or a range consisting of any two of these values. In some embodiments, 0< NS-2τ <6. In some embodiments, 0< NS-2τ.ltoreq.5. In other embodiments, 1.ltoreq.NS-2τ.ltoreq.5.
In some embodiments, 0.5< τ <5. In some embodiments, τ is 0.6, 0.8, 1, 1.2, 1.4, 1.6, 1.8, 2, 2.2, 2.4, 2.6, 2.8, 3, 3.2, 3.4, 3.6, 3.8, 4, 4.2, 4.4, 4.6, 4.8, or a range of any two of these values. In some embodiments, 1< τ <3. In other embodiments, 1.5< τ <2.5.
In some embodiments, the sulfur-containing additive comprises at least one selected from the group consisting of sulfonate, sulfate, and sulfite. The sulfur-containing additive can improve the composition and structure of the interfacial film to more effectively exert the above effects, thereby further improving the cycle performance and storage performance of the secondary battery.
In some embodiments, the sulfonate comprises at least one of the compounds of formula I-1,
Figure SMS_1
formula I-1
In the formula I-1, Q 1 And Q 2 Independently selected from C1-C6 alkylene.
In some embodiments, Q 1 And Q 2 Independently selected from C1-C4 alkylene, such as methylene, ethylene or propylene. In some embodiments, the sulfonate comprises at least one of Methylene Methylsulfonate (MMDS), ethylene ethyldisulfonate, and propylene methylsulfonate.
In some embodiments, the sulfonate comprises at least one of the compounds of formula I-2,
Figure SMS_2
formula I-2
In the formula I-2, R 1 、R 2 Independently selected from hydrogen atom or C1-C6 alkyl, Q 3 Selected from the group consisting of C1-C6 alkylene, C2-C6 alkenylene.
In some embodiments, in formula I-2, R 1 、R 2 Independently selected from hydrogen atom or C1-C4 alkyl, Q 3 Selected from the group consisting of C1-C4 alkylene, C2-C4 alkenylene.
In some embodiments, the sulfonate comprises at least one of 1, 3-Propane Sultone (PS), 1-propylene-1, 3-sultone (PST), and 1, 4-Butane Sultone (BS).
In some embodiments, the sulfate comprises at least one of the compounds of formula I-3,
Figure SMS_3
formula I-3
In the formula I-3, R 3 、R 4 、R 5 、R 6 Independently selected from hydrogen atom or C1-C6 alkyl, Q 4 Absence or Q 4 Selected from C1-C6 alkylene.
In some embodiments, in formula I-3, R 3 、R 4 、R 5 、R 6 Independently selected from hydrogen atom or C1-C4 alkyl, Q 4 Absence or Q 4 Selected from C1-C4 alkylene.
In some embodiments, in formula I-3, R 3 、R 4 、R 5 、R 6 Independently selected from hydrogen atom, methyl, ethyl, n-propyl or isopropyl group, Q 4 Is not present.
In some embodiments, the sulfate comprises at least one of vinyl sulfate (DTD), 4-methyl ethylene sulfate (PCS), 4-ethyl ethylene sulfate (PES), 4-propyl ethylene sulfate (PEGLST), and propylene sulfate (TS).
In some embodiments, the sulfite comprises at least one of the compounds of formula I-4,
Figure SMS_4
formula I-4
In the formula I-4, R 7 、R 8 、R 9 、R 10 Independently selected from hydrogen atomsSon or C1-C6 alkyl, Q 5 Absence or Q 5 Selected from C1-C6 alkylene.
In some embodiments, in formula I-4, R 7 、R 8 、R 9 、R 10 Independently selected from hydrogen atom or C1-C4 alkyl, Q 5 Absence or Q 5 Selected from C1-C4 alkylene.
In some embodiments, the sulfite comprises ethylene sulfite (DTO).
In some embodiments, the sulfite comprises at least one of the compounds of formula I-5,
Figure SMS_5
formula I-5
In the formula I-5, R 11 And R is 12 Independently selected from C1-C6 alkyl.
In some embodiments, in formula I-5, R 11 And R is 12 Independently selected from C1-C4 alkyl. In some embodiments, the sulfite comprises at least one of dimethyl sulfite (DMS) and diethyl sulfite (DES).
In some embodiments, the nitrogen-containing additive includes at least one selected from the group consisting of a nitrile compound, a phosphazene, a nitrogen-containing lithium salt, and an amide. The nitrogen-containing additive can improve the ion conductivity of the electrolyte and the composition and structure of the interface film, so that the effect can be more effectively exerted, and the cycle performance and the storage performance of the secondary battery are further improved.
In some embodiments, the nitrile compound includes at least one of the compounds represented by formula II-1,
Figure SMS_6
formula II-1
In formula II-1, R 13 Selected from C2-C10 alkylene, oxygenated C2-C10 alkylene or nitrile substituted C2-C10 alkylene.
In some embodiments, in formula II-1, R 13 Selected from C2-C6 alkylene, oxygenated C2-C6 alkylene orNitrile substituted C2-C6 alkylene, for example ethylene, propylene, butylene, pentylene, hexylene, ethylene, propylene, butylene, pentylene, hexylene containing 1 or 2 oxygen atoms, or nitrile substituted ethylene, propylene, butylene, pentylene, hexylene. In some embodiments, the nitrile compound includes at least one of Succinonitrile (SN), adiponitrile (ADN), glutaronitrile (GLN), hexanetrinitrile (HTN), and ethylene glycol (bis) propionitrile ether (DENE).
In some embodiments, the phosphazene comprises at least one of the compounds of formula II-2,
Figure SMS_7
formula II-2
In formula II-2, R 19 Selected from C1-C6 alkyl or fluoro C1-C6 alkyl, R 14 、R 15 、R 16 、R 17 And R is 18 Independently selected from hydrogen atom, fluorine atom, C1-C6 alkyl or fluorinated C1-C6 alkyl, and R 14 、R 15 、R 16 、R 17 And R is 18 At least one of them being a fluorine atom or a fluorinated C1-C6 alkyl group.
In some embodiments, in formula II-2, R 19 Selected from C1-C4 alkyl or fluoro C1-C4 alkyl, R 14 、R 15 、R 16 、R 17 And R is 18 Independently selected from fluorine atom, C1-C4 alkyl or fluoro C1-C4 alkyl, and R 14 、R 15 、R 16 、R 17 And R is 18 At least one of them being a fluorine atom or a fluorinated C1-C6 alkyl group.
In some embodiments, in formula II-2, R 19 Selected from methyl, ethyl, n-propyl, isopropyl, trifluoromethyl or 2, 2-trifluoroethyl, R 14 、R 15 、R 16 、R 17 、R 18 Independently selected from fluorine atoms or fluoro C1-C4 alkyl groups, and R 14 、R 15 、R 16 、R 17 And R is 18 At least one of them being a fluorine atom.
In some embodiments, the phosphazene comprises at least one of methoxy pentafluoroethylene triphosphazene, trifluoromethoxy pentafluoroethylene triphosphazene, ethoxy pentafluoroethylene triphosphazene (PFPN), and trifluoroethoxy pentafluoroethylene Triphosphazene (TFPN).
In some embodiments, the nitrogen-containing lithium salt comprises at least one of the compounds of formula II-3,
Figure SMS_8
formula II-3
In formula II-3, R 20 、R 21 Each independently selected from fluorine atom, C1-C6 alkyl or fluoro C1-C6 alkyl, and R 20 And R is 21 At least one of them being a fluorine atom or a fluorinated C1-C6 alkyl group.
In some embodiments, in formula II-3, R 20 、R 21 Each independently selected from fluorine atom, C1-C4 alkyl or fluoro C1-C4 alkyl, and R 20 And R is 21 At least one of them being a fluorine atom or a fluorinated C1-C4 alkyl group.
In some embodiments, the nitrogen-containing lithium salt includes at least one of lithium bis (fluorosulfonyl) imide (LiFSi), lithium bis (trifluoromethylsulfonyl) imide (LiTFSi), lithium bis (pentafluoroethanesulfonate) imide (LiBETI), and lithium (trifluoromethylsulfonyl) (perfluorobutylsulfonyl) imide (LiFNFSI).
In some embodiments, the nitrogen-containing lithium salt comprises at least one of the compounds of formula II-4,
Figure SMS_9
formula II-4
In formula II-4, R 22 、R 23 、R 24 Each independently selected from a hydrogen atom, a fluorine atom, a C1-C6 alkyl group, a fluorinated C1-C6 alkyl group or a nitrile group, and R 22 、R 23 And R is 24 At least one of them is a fluorine atom, a fluorinated C1-C6 alkyl group or a nitrile group.
In some embodiments, in formula II-4, R 22 Is a fluorine atom or a fluorinated C1-C4 alkyl group, R 23 And R is 24 At least one of them is a nitrile group. In some embodimentsWherein the nitrogen-containing lithium salt comprises lithium 4, 5-dicyano-2- (trifluoromethyl) imidazole (LiTDI).
In some embodiments, the amide comprises at least one of the compounds of formula II-5,
Figure SMS_10
formula II-5
In formula II-5, R 25 、R 26 、R 27 Each independently selected from a hydrogen atom, a C1-C6 alkyl group or a fluorinated C1-C6 alkyl group, and R 25 、R 26 And R is 27 At least one of them is a fluorinated C1-C6 alkyl group.
In some embodiments, in formula II-5, R 25 、R 26 、R 27 Each independently selected from a hydrogen atom, a C1-C4 alkyl group or a fluorinated C1-C4 alkyl group, and R 25 、R 26 And R is 27 At least one of them is a fluorinated C1-C4 alkyl group. In some embodiments, the amide comprises trifluoroacetamide.
In some embodiments, the sulfur-containing additive is present in an amount of 0.05% to 4% by mass based on the mass of the electrolyte. In some embodiments, the sulfur-containing additive is present in an amount by mass of 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.2%, 1.5%, 1.8%, 2%, 2.2%, 2.5%, 2.8%, 3%, 3.2%, 3.5%, 3.8%, 4% or a range consisting of any two of these values. In some embodiments, the sulfur-containing additive is present in an amount of 0.2% to 3% by mass.
In some embodiments, the nitrogen-containing additive is present in an amount of 0.1% to 15% by mass. In some embodiments, the nitrogen-containing additive is present in an amount of 0.2%, 0.4%, 0.6%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2%, 2.2%, 2.5%, 2.8%, 3%, 3.2%, 3.5%, 3.8%, 4%, 4.5%, 5%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 11%, 12%, 13%, 14%, 15% or a range of any two of these values by mass. In some embodiments, the nitrogen-containing additive is present in an amount of 0.2% to 10% by mass.
In some embodiments, the electrolyte further comprises other additives, the other additives include a material selected from the group consisting of Vinylene Carbonate (VC), ethylene carbonate (VEC), lithium difluorophosphate (LiDFP), tris (trimethylsilane) phosphate, tris (trimethylsilane) borate, fluoroethylene carbonate difluoro ethylene carbonate, trifluoro propylene carbonate, 2-trifluoro methyl ethyl carbonate, 2-trifluoro diethyl carbonate at least one of tris (trifluoroethyl) phosphate and 1, 2-tetrafluoroethyl-2, 3-tetrafluoropropyl ether. In some embodiments, the other additives include at least one of vinylene carbonate, ethylene carbonate, and lithium difluorophosphate.
The mass content of the other additives is 0.1% -10% based on the mass of the electrolyte. In some embodiments, the other additive is present in an amount of 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 6%, 7%, 8%, 9% or a range of any two of these values by mass. In some embodiments, the other additive is present in an amount of 0.1% to 5% by mass.
In some embodiments, the electrolyte further comprises an electrolyte lithium salt comprising a metal selected from lithium hexafluorophosphate (LiPF 6 ) Lithium tetrafluoroborate (LiBF) 4 ) At least one of lithium trifluoromethylsulfonate (LiOTf), lithium bis (fluoromalonic) borate (LiBOB), lithium bis (fluoromalonic) borate (LiBFMB), and lithium difluorooxalato borate (LiDFOB).
In some embodiments, the lithium salt may further include at least one of lithium bis (fluorosulfonyl) imide (LiFSI), lithium bis (trifluoromethylsulfonyl) imide (LiTFSI), lithium bis (pentafluoroethylsulfonate) imide (LiBETI), (trifluoromethylsulfonyl) (perfluorobutylsulfonyl) imide (LiFNFSI), and lithium 4, 5-dicyano-2- (trifluoromethyl) imidazole (liti).
In some embodiments, the electrolyte further comprises a solvent. In some embodiments, the solvent comprises at least one of a chain carbonate, a cyclic carbonate, and a carboxylate.
In some embodiments, the chain carbonate is selected from at least one of dimethyl carbonate, diethyl carbonate, dipropyl carbonate, methylethyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, and fluoro chain carbonate. In some embodiments, the cyclic carbonate comprises at least one of ethylene carbonate, propylene carbonate, and butylene carbonate. In some embodiments, the carboxylic acid ester is selected from at least one of methyl formate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, gamma-butyrolactone, and a fluorocarboxylic acid ester.
In some embodiments, the solvent comprises a chain carbonate and/or a cyclic carbonate, the mass content of which is above 90%, e.g. above 95%, 98% based on the mass of the solvent. In some embodiments, the solvent does not include a carboxylate. In some embodiments, the solvent does not include an ether.
In some embodiments, the positive electrode includes a positive electrode active material layer, and the positive electrode active material includes at least one selected from lithium nickel transition metal oxides. In some embodiments, the lithium nickel transition metal oxide has a chemical formula of LiNi m Co n A (1-m-n) O 2 Wherein A is selected from at least one of Mn, al, mg, cr, ca, zr, mo, ag or Nb, m is more than or equal to 0.5 and less than or equal to 1, n is more than or equal to 0 and less than or equal to 0.5, and m+n is more than or equal to 1.
In some embodiments, m is 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, or a range consisting of any two of these values. In some embodiments, n is 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, or a range consisting of any two of these values.
In some embodiments, the lithium nickel transition metal oxide comprises at least one of NCA, NCM111, NCM523, NCM622, NCM811, ni90, ni92, or Ni 95.
In some embodiments, the positive electrode active material may also include at least one of phosphate-based compounds having a chemical formula of LiMn k B (1-k) PO 4 Wherein k is more than or equal to 0 and less than or equal to 1, and B element is at least one of iron, cobalt, magnesium, calcium, zinc, chromium or lead. In some implementationsIn embodiments, k is 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, or a range of any two of these values. In some embodiments, the phosphate-based compound comprises lithium iron phosphate, liMn 0.6 Fe 0.4 PO 4 Or LiMn 0.8 Fe 0.2 PO 4 At least one of them.
In some embodiments, the positive electrode active material layer further includes a binder, and optionally includes a conductive agent. The binder enhances the bonding of the positive electrode active material particles to each other and also enhances the bonding of the positive electrode active material to the current collector.
In some embodiments, the binder includes, but is not limited to: polyvinyl alcohol, hydroxypropyl cellulose, diacetyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, an ethyleneoxy-containing polymer, polyvinylpyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, acrylated styrene-butadiene rubber, epoxy resin, nylon, or the like.
In some embodiments, the conductive agent includes, but is not limited to: carbon-based materials, metal-based materials, conductive polymers, and mixtures thereof. In some embodiments, the carbon-based material is selected from natural graphite, synthetic graphite, carbon black, acetylene black, ketjen black, carbon fiber, or any combination thereof. In some embodiments, the metal-based material is selected from metal powder, metal fiber, copper, nickel, aluminum, or silver. In some embodiments, the conductive polymer is a polyphenylene derivative.
In some embodiments, the positive electrode further includes a positive electrode current collector, which may be a metal foil or a composite current collector. For example, aluminum foil may be used. The composite current collector may be manufactured by a process of forming a metal material (copper, copper alloy, nickel alloy, titanium alloy, silver alloy, etc.) on a polymer substrate.
In some embodiments, the anode includes an anode active material layer, and the anode active material includes a silicon-based material. The silicon-based material includes at least one of silicon, a silicon alloy, a silicon oxygen compound, and a silicon carbon compound. In some embodiments, the silicon-based material comprises a silicon oxygen compound and/or a silicon carbon compound.
In some embodiments, the negative electrode active material further includes a mixture of at least one of a carbon-based material, a tin-based material, a phosphorus-based material, and metallic lithium. The carbon-based material includes at least one of graphite, soft carbon, hard carbon, carbon nanotubes, and graphene. The tin-based material includes at least one of tin, tin oxide, and tin alloy. The phosphorus-based material includes phosphorus and/or a phosphorus compound.
In some embodiments, the mass content g% of the silicon-based material, based on the mass of the anode active material, satisfies: g is more than or equal to 10 and less than or equal to 100. In some embodiments, g is 11, 13, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or a range of any two of these values. In some embodiments, 10.ltoreq.g.ltoreq.50. In other embodiments, 12.ltoreq.g.ltoreq.35.
In some embodiments, the anode active material layer further includes a binder and a conductive agent. In some embodiments, the binder includes, but is not limited to: polyvinyl alcohol, hydroxypropyl cellulose, diacetyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, an ethyleneoxy-containing polymer, polyvinylpyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, acrylated styrene-butadiene rubber, epoxy resin, nylon, or the like.
In some embodiments, the conductive agent includes, but is not limited to: carbon-based materials, metal-based materials, conductive polymers, and mixtures thereof. In some embodiments, the carbon-based material is selected from natural graphite, synthetic graphite, carbon black, acetylene black, ketjen black, carbon fiber, or any combination thereof. In some embodiments, the metal-based material is selected from metal powder, metal fiber, copper, nickel, aluminum, or silver. In some embodiments, the conductive polymer is a polyphenylene derivative.
In some embodiments, the negative electrode further comprises a negative electrode current collector comprising: copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, a polymer substrate coated with a conductive metal, or any combination thereof.
In some embodiments, a separator is provided between the positive and negative electrodes to prevent shorting. The materials and shape of the release film that can be used in the embodiments of the present application are not particularly limited, and can be any of the techniques disclosed in the prior art. In some embodiments, the separator comprises a polymer or inorganic, etc., formed from a material that is stable to the electrolyte of the present application.
For example, the release film may include a substrate layer and a surface treatment layer. The substrate layer is a non-woven fabric, a film or a composite film with a porous structure, and the material of the substrate layer comprises at least one of polyethylene, polypropylene, polyethylene terephthalate or polyimide. Specifically, a polypropylene porous membrane, a polyethylene porous membrane, a polypropylene nonwoven fabric, a polyethylene nonwoven fabric or a polypropylene-polyethylene-polypropylene porous composite membrane can be selected.
The surface treatment layer is provided on at least one surface of the base material layer, and the surface treatment layer may be a polymer layer or an inorganic layer, or may be a layer formed by mixing a polymer and an inorganic substance.
The inorganic layer includes inorganic particles including at least one of aluminum oxide, silicon oxide, magnesium oxide, titanium oxide, hafnium oxide, tin oxide, cerium oxide, nickel oxide, zinc oxide, calcium oxide, zirconium oxide, yttrium oxide, silicon carbide, boehmite, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, or barium sulfate, and a binder. The binder comprises at least one of polyvinylidene fluoride, 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, acrylic polymer, polyacrylic acid, polyacrylate, polyvinylpyrrolidone, polyvinyl ether, polyvinylidene fluoride or poly (vinylidene fluoride-hexafluoropropylene).
In some embodiments, the method of manufacturing the secondary battery includes providing an electrode assembly, injecting a liquid, packaging, and forming. In some embodiments, the temperature of the formation is 40 ℃ to 50 ℃, such as 41 ℃, 42 ℃, 43 ℃, 44 ℃, 45 ℃, 46 ℃, 47 ℃, 48 ℃, or 49 ℃. In some embodiments, the pressure of the formation is 150kgf to 250kgf, for example 160kgf, 170kgf, 180kgf, 190kgf, 200kgf, 210kgf, 220kgf, 230kgf, or 240kgf. In some embodiments, the charging current of the formation is 0.05C-0.1C and the discharging current of the formation is 0.1C-0.3C.
In some embodiments, the forming comprises: under conditions of a temperature of 40℃to 50℃such as 45℃and a pressure of 150kgf to 250kgf such as 200kgf, a current of 0.05C is charged to 4.2V and left standing for 60min, followed by charging of 0.1C to 4.2V, and then discharging of 0.2C to 3.0V.
In some embodiments, the secondary battery is a lithium secondary battery or a sodium secondary battery. In some embodiments, lithium secondary batteries include, but are not limited to: lithium metal secondary batteries, lithium ion secondary batteries, lithium polymer secondary batteries, or lithium ion polymer secondary batteries.
In some embodiments, the secondary battery may include an outer package, which may be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, or the like. The exterior package of the secondary battery may also be a pouch type pouch, for example. The soft bag can be made of one or more of polypropylene (PP), polybutylene terephthalate (PBT), polybutylene succinate (PBS), etc.
In some embodiments, the shape of the secondary battery is not particularly limited, and may be cylindrical, square, or any other shape.
In some embodiments, the present application also provides a battery module. The battery module includes the secondary battery described above. The battery module of the present application employs the above-described secondary battery, and thus has at least the same advantages as the secondary battery. The number of secondary batteries contained in the battery module of the present application may be plural, and the specific number may be adjusted according to the application and capacity of the battery module.
In some embodiments, the present application also provides a battery pack including the above battery module. The number of battery modules included in the battery pack may be adjusted according to the application and capacity of the battery pack.
2. Device and method for controlling the same
The present application also provides an apparatus comprising at least one of the above secondary battery, battery module or battery pack.
In some embodiments, the apparatus includes, but is not limited to: electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric storage systems, and the like. In order to meet the high power and high energy density requirements of the device for the secondary battery, a battery pack or a battery module may be employed.
In other embodiments, the device may be a cell phone, tablet, notebook, or the like. The device is generally required to be light and thin, and a secondary battery can be used as a power source.
Examples
Test method
1. Determination of pole piece tortuosity
The tortuosity of the pole piece can be obtained by an image recognition and analysis method, and specifically comprises the following steps: firstly, taking a morphology picture of the electrode surface through a scanning electron microscope SEM, then importing the picture into Wolfram Mathematica software, running a tortuosity index estimation code file CDF, calibrating the outline of active substance particles in the surface picture, clicking a Fit button, calculating the a, b and c triaxial characteristics and the particle orientation angle of the calibrated particles, clicking a calculation button, and calculating tortuosity indexes aX, aY and aZ of XYZ in three directions, wherein the aZ value is the tortuosity index of the pole piece, and tortuosity tau = epsilon -aZ 。
Wherein epsilon is the porosity of the pole piece, which is measured by a mercury porosimeter, and is specifically as follows: the dried pole piece samples were slit into strips of a certain size and the apparent volume of the pole piece coating was determined using a ten-thousandth ruler, apparent volume = sample coating thickness x sample length x sample width. The pole piece is then vacuum degassed and wound in a sample cell, the volume of the sample must be ensured to be 40-70% of the effective volume of the sample tube, so as to ensure measurement accuracy, and then the pore volume of the sample, i.e. the volume of mercury pressed into the sample, is measured by using a mercury porosimeter, so that the porosity epsilon=pore volume/apparent volume.
2. Battery internal resistance test
Discharging the lithium ion battery to a cut-off voltage of 3.0V at a constant current of 1C, charging for 18min at a constant current of 1C after the lithium ion battery is placed at 20+/-2 ℃ for 1h, adjusting the SOC to 30%, placing for 1h, recording a voltage U1 after the placement is finished, charging for 1.5min at a constant current of 3C, placing for 1h, discharging for 0.5min at a constant current of 9C, placing for 1h, charging for 6min at a constant current of 1C, adjusting the SOC to 40%, and placing for 1h. And (3) circulating until the SOC is 70%, recording the current of the voltage U2 and the voltage U1C after the standing is finished as I, and calculating to obtain the DCR value through the formula R=U2-U1/I.
3. Battery cycle capacity retention test
The lithium ion battery is charged to 4.25V at a constant current of 1C at 25 ℃, then charged to 0.05C at a constant voltage of 4.25V, and then discharged to 2.5V at a constant current of 1C. After 500 cycles of charge and discharge, the capacity retention after 500 cycles at 25℃was calculated according to the following formula: the discharge capacity after 500 th cycle/the discharge capacity after first cycle is multiplied by 100%.
The lithium ion battery is charged to 4.25V at a constant current of 1C at 45 ℃, then charged to 0.05C at a constant voltage of 4.25V, and then discharged to 2.5V at a constant current of 1C. After 400 cycles of charge and discharge, the capacity retention after 400 cycles at 45℃was calculated according to the following formula: the discharge capacity after 400 th cycle/the discharge capacity after first cycle is multiplied by 100%.
4. Cell 45 ℃ storage thickness change rate test
The cell was discharged to 3.0V at 25 ℃ with a constant current of 0.5C, charged to 4.45V with a constant current of 0.5C, then charged to 0.05C with a constant voltage of 4.45V, and the thickness of the cell was measured using a PPG soft pack cell thickness gauge and recorded as a. The battery was placed in an oven and stored for 15 days at a constant voltage of 4.45V at 45 ℃ for 15 days, and the thickness after 15 days of testing was noted as b, and the calculation formula of the thickness expansion ratio was: (b-a)/a.times.100%.
5. CEI film sulfur and Nitrogen content test
Discharging the lithium ion battery to 2.5V at the current of 0.1C, and dismantling the lithium ion battery in a glove box filled with argon to obtain the electrode plate. Cutting the obtained positive electrode plate into test samples with the size of 8mm multiplied by 8mm, soaking and cleaning for half an hour by using a low-boiling point dimethyl carbonate (DMC) solvent, sticking the test samples on a sample table of XPS after the test samples are completely dried, enabling the surface of the positive electrode active material layer, which is far away from a current collector, to face upwards, and measuring under the condition of not being exposed to the atmosphere. The specific test conditions and steps are as follows:
the mass percent of elemental sulfur and elemental nitrogen was calculated using single crystal spectral alkα radiation, using 1000X 1750 μm ellipse form output at 10KV and 22mA for the X-ray point, selecting data at sputter etch time of 0 seconds, using 284.8eV for neutral carbon C1s, and using 3-point smoothing, peak area measurement, background subtraction and peak synthesis for data processing such as peak differentiation.
Example 1
The preparation method of the positive electrode comprises the following steps: the positive electrode active material LiNi 0.9 Co 0.05 Mn 0.05 O 2 The conductive agent carbon nano tube/acetylene black, the binder polyvinylidene fluoride PVDF, and the weight ratio of LiNi 0.9 Co 0.05 Mn 0.05 O 2 And (2) fully homogenizing the mixture of CNT/Super-P (polyvinylidene fluoride) and PVDF (polyvinylidene fluoride) =95:2.0/1.0:2 in an N-methylpyrrolidone (NMP) solvent system, and then coating the mixture on a 12-mu m-thick aluminum-coated current collector, drying and rolling the mixture to obtain a positive electrode plate, wherein the tortuosity of the positive electrode plate is 1.98.
The preparation method of the negative electrode comprises the following steps: silicon oxide (SiO) as a negative electrode active material x X is more than or equal to 0.5 and less than or equal to 1.5), graphite compound (the mass ratio of silicon oxide to graphite in the compound is 14:86), conductive agent acetylene black, adhesive styrene-butadiene rubber SBR, thickener sodium carboxymethyl cellulose CMCNa and polyacrylic acid PAA are fully homogenized in deionized water according to the weight ratio of 96:2:1.5:1:0.5, and then the mixture is coated on the surface of an 8 mu m thick copper current collector, and the negative electrode plate is obtained after drying, rolling and stripping.
A diaphragm: adopts a PP/PE/PP three-layer composite diaphragm.
Preparing an electrolyte: in an argon-filled glove box (H) 2 O＜0.1ppm，O 2 < 0.1 ppm), lithium salt LiPF 6 And solvent EC/DEC/emc=25/20/55 were uniformly mixed in a certain ratio to prepare a 1M solution, and finally, the sulfur-containing compound additive (0.6% by total mass of the electrolyte) and the nitrogen-containing compound additive (1% by total mass of the electrolyte) in table 1 were added, and the solution was uniformly stirred to obtain a lithium ion battery electrolyte of example 1.
Preparation of a lithium ion battery: sequentially stacking the prepared positive pole piece, the diaphragm and the negative pole piece, enabling the diaphragm to be positioned between the positive pole piece and the negative pole piece, and winding to obtain a bare cell; the bare cell is placed in an aluminum plastic film outer package, the prepared lithium ion battery electrolyte is injected after the bare cell is fully dried, the battery is placed at 45 ℃ for 48 hours and is formed by high-temperature clamping (the formation condition is that the temperature is 45 ℃, the pressure is 200kgf, the current is charged to 4.2V for 60 minutes after 0.05C, then the current is charged to 4.2V after 0.1C, then the current is discharged to 3.0V after 0.2C, and the battery is repeatedly subjected to twice) and sealed for two times, and then the conventional capacity division is carried out.
Examples 2 to 11 and comparative examples 1 to 11
Examples 2 to 11 and comparative examples 1 to 11 were achieved by adjusting the kinds and contents of additives in the electrolyte, tortuosity of the positive electrode sheet (wherein tortuosity is achieved by adjusting the positive electrode roll line load during the preparation process, etc.), formation conditions, etc. on the basis of example 1, specific adjustment measures and detailed data are shown in table 1.
TABLE 1
Figure SMS_11
The battery performance test results of examples 1 to 11 and comparative examples 1 to 11 are shown in Table 2.
TABLE 2
Figure SMS_12
While certain exemplary embodiments of the present application have been illustrated and described, the present application is not limited to the disclosed embodiments. Rather, one of ordinary skill in the art will recognize that certain modifications and changes may be made to the described embodiments without departing from the spirit and scope of the present application, as described in the appended claims.

Claims (10)

1. A secondary battery includes a positive electrode, a negative electrode, and an electrolyte, wherein,
the electrolyte includes a sulfur-containing additive and a nitrogen-containing additive;
the positive electrode comprises a positive electrode active material layer and a solid electrolyte interface film positioned on the surface of the positive electrode active material layer, wherein the solid electrolyte interface film is tested by adopting an X-ray photoelectron spectrometer, the mass percentage of sulfur element in the solid electrolyte interface film is S, and the mass percentage of nitrogen element is N, wherein 2S-N is more than 0 and less than or equal to 1.5.
2. The secondary battery according to claim 1, wherein 0.2.ltoreq.s.ltoreq.10, and/or 1.ltoreq.n.ltoreq.12.
3. The secondary battery according to claim 1 or 2, wherein 0.5.ltoreq.s.ltoreq.5, and/or 2.ltoreq.n.ltoreq.10.
4. The secondary battery according to claim 1 or 2, wherein the positive electrode has a pole piece tortuosity of τ, wherein 0< ns-2τ <8.
5. The secondary battery according to claim 4, wherein 0.5< τ <5.
6. The secondary battery according to claim 1 or 2, wherein the sulfur-containing additive comprises at least one selected from the group consisting of a sulfonate, a sulfate and a sulfite, wherein,
the sulfonate comprises at least one of the compounds shown in the formula I-1 and the formula I-2,
Figure QLYQS_1
formula I-1, ">
Figure QLYQS_2
Formula I-2
In the formula I-1, Q 1 And Q 2 Independently selected from C1-C6 alkylene, in formula I-2, R 1 、R 2 Independently selected from hydrogen atom or C1-C6 alkyl, Q 3 Selected from C1-C6 alkylene, C2-C6 alkenylene;
the sulfate comprises at least one of the compounds shown in the formula I-3,
Figure QLYQS_3
formula I-3
In the formula I-3, R 3 、R 4 、R 5 、R 6 Independently selected from hydrogen atom or C1-C6 alkyl, Q 4 Absence or Q 4 Selected from C1-C6 alkylene;
the sulfite comprises at least one of the compounds shown in the formula I-4 and the formula I-5,
Figure QLYQS_4
formula I-4, ">
Figure QLYQS_5
Formula I-5
In the formula I-4, R 7 、R 8 、R 9 、R 10 Independently selected from hydrogen atom or C1-C6 alkyl, Q 5 Absence or Q 5 Selected from C1-C6 alkylene, of formula I-5, R 11 And R is 12 Independently selected from C1-C6 alkyl; and/or the number of the groups of groups,
the nitrogen-containing additive includes at least one selected from the group consisting of a nitrile compound, a phosphazene, a nitrogen-containing lithium salt, and an amide, wherein,
the nitrile compound includes at least one of the compounds represented by formula II-1,
Figure QLYQS_6
formula II-1
In formula II-1, R 13 Selected from C2-C10 alkylene, oxygenated C2-C10 alkylene, or nitrile substituted C2-C10 alkylene;
the phosphazene comprises at least one of compounds shown in a formula II-2,
Figure QLYQS_7
formula II-2
In formula II-2, R 19 Selected from C1-C6 alkyl or fluoro C1-C6 alkyl, R 14 、R 15 、R 16 、R 17 、R 18 Independently selected from hydrogen atom, fluorine atom, C1-C6 alkyl or fluorinated C1-C6 alkyl, and R 14 、R 15 、R 16 、R 17 、R 18 At least one of them is a fluorine atom or a fluorinated C1-C6 alkyl group;
the nitrogen-containing lithium salt comprises at least one of the compounds shown in the formulas II-3 and II-4,
Figure QLYQS_8
formula II-3, -/->
Figure QLYQS_9
Formula II-4
In formula II-3, R 20 、R 21 Each independently selected from fluorine atom, C1-C6 alkyl or fluoro C1-C6 alkyl, and R 20 And R is 21 At least one of them is a fluorine atom or a fluorinated C1-C6 alkyl group, in the formula II-4, R 22 、R 23 、R 24 Each independently selected from a hydrogen atom, a fluorine atom, a C1-C6 alkyl group, a fluorinated C1-C6 alkyl group or a nitrile group, and R 22 、R 23 And R is 24 At least one of them is a fluorine atom, a fluorinated C1-C6 alkyl group or a nitrile group;
the amide comprises at least one of the compounds represented by formula II-5,
Figure QLYQS_10
formula II-5
In formula II-5, R 25 、R 26 、R 27 Each independently selected from a hydrogen atom, a C1-C6 alkyl group or a fluorinated C1-C6 alkyl group, and R 25 、R 26 And R is 27 At least one of them is a fluorinated C1-C6 alkyl group.
7. The secondary battery according to claim 6, wherein the sulfonate ester comprises at least one of methyl methylene disulfonate, ethyl ethylene disulfonate, methyl propylene disulfonate, 1, 3-propane sultone, 1-propylene-1, 3-sultone, and 1, 4-butane sultone, and/or,
the sulfate comprises at least one of vinyl sulfate, 4-methyl ethylene sulfate, 4-ethyl ethylene sulfate, 4-propyl ethylene sulfate and propylene sulfate, and/or,
the sulfite comprises at least one of ethylene sulfite, dimethyl sulfite and diethyl sulfite, and/or,
the nitrile compound includes at least one of succinonitrile, adiponitrile, glutaronitrile, hexanetrinitrile and ethylene glycol (bis) propionitrile ether, and/or,
the phosphazenes comprise at least one of methoxy pentafluoroethyl triphosphazene, trifluoromethoxy pentafluoroethyl triphosphazene, ethoxy pentafluoroethyl triphosphazene and trifluoroethoxy pentafluoroethyl triphosphazene, and/or,
the nitrogen-containing lithium salt includes at least one of lithium bis (fluorosulfonyl) imide, lithium bis (pentafluoroethyl sulfonate) imide, lithium (trifluoromethylsulfonyl) (perfluorobutylsulfonyl) imide, and lithium 4, 5-dicyano-2- (trifluoromethyl) imidazole, and/or,
the amide comprises trifluoroacetamide.
8. The secondary battery according to claim 1 or 2, wherein the mass content of the sulfur-containing additive is 0.05% to 4% based on the mass of the electrolyte; and/or the number of the groups of groups,
the mass content of the nitrogen-containing additive is 0.1% -15% based on the mass of the electrolyte; and/or the number of the groups of groups,
the electrolyte further comprises other additives, wherein the other additives comprise at least one of ethylene carbonate, ethylene carbonate and lithium difluorophosphate, and the mass content of the other additives is 0.1-10% based on the mass of the electrolyte; and/or the number of the groups of groups,
the electrolyte includes a solvent including a chain carbonate and/or a cyclic carbonate, the mass content of the chain carbonate and/or the cyclic carbonate being 90% or more based on the mass of the solvent.
9. The secondary battery according to claim 1 or 2, wherein the positive electrode comprises an active material selected from lithium nickel transition metal oxides having a chemical formula of LiNi m Co n A (1-m-n) O 2 Wherein, A is selected from at least one of manganese, aluminum, magnesium, chromium, calcium, zirconium, molybdenum, silver or niobium, m is more than or equal to 0.5 and less than or equal to 1, n is more than or equal to 0 and less than or equal to 0.5, and m+n is more than or equal to 1; and/or the number of the groups of groups,
the negative electrode includes an active material selected from a silicon-based material including at least one of silicon, a silicon alloy, a silicon oxygen compound, and a silicon carbon compound, and the mass content g% of the silicon-based material, based on the mass of the negative electrode active material, satisfies: g is more than or equal to 10 and less than or equal to 100.
10. An apparatus comprising the secondary battery according to any one of claims 1 to 9.
CN202310678976.3A 2023-06-09 2023-06-09 Secondary battery and device Pending CN116417677A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310678976.3A CN116417677A (en) 2023-06-09 2023-06-09 Secondary battery and device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310678976.3A CN116417677A (en) 2023-06-09 2023-06-09 Secondary battery and device

Publications (1)

Publication Number Publication Date
CN116417677A true CN116417677A (en) 2023-07-11

Family

ID=87059693

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310678976.3A Pending CN116417677A (en) 2023-06-09 2023-06-09 Secondary battery and device

Country Status (1)

Country Link
CN (1) CN116417677A (en)

Similar Documents

Publication Publication Date Title
US11355742B2 (en) Negative electrode plate and lithium-ion secondary battery
CN112310483B (en) Lithium ion battery
CN109361018B (en) Electrolyte solution and electrochemical device
CN116314595B (en) Secondary battery and device
TWI605633B (en) Negative active material for rechargeable lithium battery, method for preparing same, and rechargeable lithium battery comprising same
CN116454393B (en) Secondary battery and device
CN116154177B (en) Secondary battery and device
EP3588625B1 (en) Positive electrode plate and lithium-ion secondary battery
CN116154176B (en) Secondary battery and device
CN116454394B (en) Secondary battery and device
CN116525949A (en) Secondary battery and device
CN116231091A (en) Electrolyte for lithium secondary battery, and electricity using device
CN116435602B (en) Secondary battery and device
CN112103561B (en) Electrolyte and electrochemical device
CN109119599B (en) Secondary battery and preparation method thereof
CN116470143B (en) Secondary battery and device
CN111477964B (en) Electrolyte and electrochemical device
CN116544348A (en) Secondary battery and device
CN116759646A (en) Secondary battery and electricity utilization device
JP4581503B2 (en) Non-aqueous electrolyte battery
CN116404258B (en) Secondary battery and device
CN116417677A (en) Secondary battery and device
CN116417569B (en) Secondary battery and device
CN116417570B (en) Secondary battery and device
CN116435600B (en) Secondary battery and device

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