Positive electrode slurry for rechargeable lithium battery and rechargeable lithium battery

Abstract

The present disclosure relates to a positive electrode slurry for a rechargeable lithium battery and a rechargeable lithium battery. The positive electrode slurry for a rechargeable lithium battery includes a positive electrode active material, a binder, and a positive electrode additive, wherein the positive electrode additive includes a compound represented by Chemical Formula 1: Chemical Formula 1:

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2024-0179301, filed on December 5, 2024, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] This disclosure relates to a positive electrode slurry for a rechargeable lithium battery and a rechargeable lithium battery including a positive electrode. Background Technology

[0004] With the increasing prevalence of battery-powered electronic devices (such as mobile phones, laptops, electric vehicles, etc.), the demand for rechargeable batteries with high energy density and high capacity (e.g., rechargeable lithium batteries) has increased. Accordingly, improving the performance of rechargeable lithium batteries is advantageous.

[0005] A rechargeable lithium battery includes a positive electrode and a negative electrode (the positive electrode and the negative electrode include active materials capable of inserting and deintercalating lithium ions) and an electrolyte. When lithium ions are inserted into or deintercalated from the positive electrode and the negative electrode, the rechargeable lithium battery generates electrical energy through oxidation and reduction reactions. Summary of the Invention

[0006] One example implementation includes a positive electrode slurry for a rechargeable lithium battery, which can be used to implement a positive electrode for a rechargeable lithium battery, providing reduced resistance and reduced gas generation during high-voltage and high-temperature storage.

[0007] One example embodiment includes a positive electrode slurry for a rechargeable lithium battery, comprising a positive electrode active material, a binder, and a positive electrode additive, wherein the positive electrode additive comprises an additive of Formula 1 (a compound represented by Formula 1):

[0008] Chemical Formula 1:

[0009] .

[0010] In chemical formula 1,

[0011] R 1 R 2 R 3 and R 4 Each as defined in the following description of this disclosure.

[0012] Another example implementation includes a rechargeable lithium battery comprising a positive electrode (formed from or comprising a positive electrode active material slurry) and a negative electrode (comprising a negative electrode active material). Attached Figure Description

[0013] The accompanying drawings illustrate exemplary embodiments of the present disclosure and, together with the detailed description of the present disclosure, further describe aspects and features of the present disclosure. Therefore, the present disclosure should not be construed as limited to the drawings, wherein:

[0014] Figure 1 A conceptual diagram of a rechargeable lithium battery according to an example embodiment of the present disclosure is shown for illustrative purposes.

[0015] Figures 2-5 A diagram illustrating a rechargeable lithium battery according to an example embodiment is shown for illustrative purposes. Detailed Implementation

[0016] To fully understand the configuration and effects of this disclosure, exemplary embodiments of this disclosure are described with reference to the accompanying drawings. However, it should be understood that the exemplary embodiments disclosed below can be embodied in various forms and modified in various ways, and are not limited to the exemplary embodiments described herein. The description of these exemplary embodiments is provided only to ensure that the disclosure is complete and to fully inform those skilled in the art of the scope of this disclosure.

[0017] In this specification, when any component is referred to as being "on" another component, it means that the component can be formed directly on the other component, or that a third component can be inserted between them. Furthermore, in the accompanying drawings, the dimensions (e.g., thickness) of components may be enlarged for effective description of the technical content. Throughout this specification, portions indicated by the same reference numerals denote the same components.

[0018] Unless otherwise indicated in this specification, any feature indicated in the singular may also include the plural. Furthermore, unless otherwise specifically stated herein, “A or B” may mean “including A, including B, or including both A and B”. As used in this specification, the terms “comprising” and / or “including” do not exclude the presence or addition of one or more other components.

[0019] In this specification, the term "combination thereof" may refer to mixtures of components, laminates, composites, copolymers, alloys, blends, reaction products, etc.

[0020] Unless otherwise defined in this specification, the term "substitution" means that at least one hydrogen atom in a substituent or compound is replaced by at least one of the following: deuterium, halogen, hydroxyl, amino, C1-C30 amino, nitro, C1-C40 silyl, C1-C30 alkyl, C1-C10 alkylsilyl, C6-C30 arylsilyl, C3-C30 cycloalkyl, C3-C30 heterocycloalkyl, C6-C30 aryl, C2-C30 heteroaryl, C1-C20 alkoxy, C1-C10 fluoroalkyl, cyano, or a combination thereof.

[0021] For example, the term "substitution" may mean that at least one hydrogen atom in a substituent or compound is replaced by: deuterium, halogroup, C1-C30 alkyl, C1-C10 alkylsilyl, C6-C30 arylsilyl, C3-C30 cycloalkyl, C3-C30 heterocycloalkyl, C6-C30 aryl, C2-C30 heteroaryl, C1-C10 fluoroalkyl, or cyano. Alternatively, the term "substitution" may mean that at least one hydrogen atom in a substituent or compound is replaced by: deuterium, halogroup, C1-C20 alkyl, C6-C30 aryl, C1-C10 fluoroalkyl, or cyano. As an example, the term "substitution" may mean that at least one hydrogen atom in a substituent or compound is replaced by one of the following: deuterium, cyano, halogen, methyl, ethyl, propyl, butyl, phenyl, biphenyl, terphenyl, trifluoromethyl, or naphthyl.

[0022] Unless otherwise specified in this specification, the symbol “ "" refers to the portion connected to the same or different atoms or chemical formulas. Unless specifically mentioned in the chemical formula described in this specification, hydrogen bonds are present in the structure of the chemical formula.

[0023] When the terms “about” or “substantially” are used in conjunction with numerical values ​​in this specification, it means that the relevant numerical value includes a tolerance of ±10% around the stated value. When a range is specified, the range includes all values ​​within it, such as increments of 0.1%.

[0024] Figure 1 A conceptual diagram of a rechargeable lithium battery according to an example embodiment of the present disclosure is shown for illustrative purposes. Reference Figure 1 A rechargeable lithium battery may include a positive electrode 10, a negative electrode 20, a separator 30, and an electrolyte ELL.

[0025] The positive electrode 10 and the negative electrode 20 may be spaced apart from each other by a diaphragm 30 inserted between them. The diaphragm 30 may be disposed between the positive electrode 10 and the negative electrode 20. The positive electrode 10, the negative electrode 20 and the diaphragm 30 may be in contact with the electrolyte ELL. The positive electrode 10, the negative electrode 20 and the diaphragm 30 may be impregnated with the electrolyte ELL.

[0026] The electrolyte ELL may be or include a medium for transporting lithium ions between the positive electrode 10 and the negative electrode 20. In the electrolyte ELL, lithium ions can pass through the separator 30 to move toward the positive electrode 10 or the negative electrode 20.

[0027] Positive electrode 10

[0028] The positive electrode 10 for a rechargeable lithium battery may include a positive electrode current collector COL1 and a positive electrode active material layer AML1 formed on the positive electrode current collector COL1. The positive electrode active material layer AML1 includes a positive electrode active material and may further include a binder and / or a conductive material.

[0029] As an example, the positive electrode 10 may further include components that can constitute a sacrificial positive electrode.

[0030] Based on 100% by weight of the positive electrode active material layer AML1, the content of the positive electrode active material in the positive electrode active material layer AML1 can be in the range of about 90% by weight to about 99% by weight. Based on 100% by weight of the positive electrode active material layer AML1, the content of the binder and the conductive material can each independently be in the range of about 0.5% by weight to about 5% by weight.

[0031] The binder bonds the positive electrode active material particles together and to the positive electrode current collector COL1. Representative examples of binders include at least one of polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, diacetyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, ethylene oxide-containing polymers, polyvinylpyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, (meth)acrylated styrene-butadiene rubber, epoxy resin, (meth)acrylate resin, polyester resin, nylon, etc., but this disclosure is not limited thereto.

[0032] Conductive materials impart conductivity to electrodes, and any material can be used as long as it is conductive and does not cause undesirable chemical changes in the battery to be formed. Examples of conductive materials include carbon-based materials (such as at least one of natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, carbon fiber, carbon nanofiber, carbon nanotube, etc.); metallic materials in the form of metal powders or metal fibers containing at least one of copper, nickel, aluminum, silver, etc.; conductive polymers (such as polyphenylene derivatives, etc.); or mixtures thereof.

[0033] Al foil can be used as the positive electrode current collector COL1, but this disclosure is not limited thereto.

[0034] Positive electrode active material

[0035] As the positive electrode active material in the positive electrode active material layer AML1, a compound capable of reversibly inserting and de-intercalating lithium (lithiation-intercalated compound) can be used. For example, at least one of the composite oxides of lithium with a metal (such as or including at least one of cobalt, manganese and nickel) can be used.

[0036] The composite oxide may be or include lithium transition metal composite oxides, and examples of such composite oxides include at least one of lithium nickel oxides, lithium cobalt oxides, lithium manganese oxides, lithium iron phosphate compounds, and cobalt-free nickel manganese oxides.

[0037] As an example, a compound represented by any of the following chemical formulas can be used: Li a A 1-b X b O 2-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Mn 2-b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Ni 1-b-c Co b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0≤α≤2); Li a Ni 1-b- c Mn b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0≤α≤2); Lia Ni b Co c L 1 d G e O2 (0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0≤e≤0.1); Li a NiG b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a CoG b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-b G b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn2G b O4 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-g G g PO4 (0.90≤a≤1.8, 0≤g≤0.5); Li (3-f) Fe2(PO4)3 (0≤f≤2); and Li a FePO4 (0.90≤a≤1.8).

[0038] In the above chemical formulas, A is or includes at least one of Ni, Co, and Mn; X is or includes at least one of Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, and rare earth elements; D is or includes at least one of O, F, S, and P; G is or includes at least one of Al, Cr, Mn, Fe, Mg, La, Ce, Sr, and V; and L 1 It may include at least one of Mn and Al.

[0039] As an example, the positive electrode active material may be or include a high-nickel positive electrode active material, wherein the nickel content is in the range of about 80 mol% or more, about 85 mol% or more, about 90 mol% or more, about 91 mol% or more, or about 94 mol% or more and about 99 mol% or less, based on 100 mol% of metals other than lithium in the lithium transition metal complex oxide (high-nickel positive electrode active material). High-nickel positive electrode active materials can achieve high capacity and are therefore applicable to high-capacity, high-energy-density rechargeable lithium batteries.

[0040] negative electrode 20

[0041] The negative electrode 20 for a rechargeable lithium battery includes a negative electrode current collector COL2 and a negative electrode active material layer AML2 disposed on the negative electrode current collector COL2. The negative electrode active material layer AML2 includes a negative electrode active material and may further include a binder and / or a conductive material.

[0042] For example, based on 100% by weight of the negative electrode active material layer AML2, the negative electrode active material layer AML2 may include a negative electrode active material ranging from about 90% by weight to about 99.5% by weight, a binder ranging from about 0.5% by weight to about 5% by weight, and a conductive material ranging from about 0% by weight to about 5% by weight.

[0043] The binder bonds the negative electrode active material particles together and to the negative electrode current collector COL2. Non-aqueous binders, aqueous binders, dry binders, or combinations thereof can be used as binders.

[0044] Non-aqueous adhesives include at least one of polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, ethylene-propylene copolymer, polystyrene, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyamide-imide, and polyimide.

[0045] The waterborne adhesive may be or include at least one of styrene-butadiene rubber, (meth)acrylated styrene-butadiene rubber, (meth)acrylonitrile-butadiene rubber, (meth)acrylic rubber, butyl rubber, fluoroelastomer, polyethylene oxide, polyvinylpyrrolidone, polyepoxychloropropane, polyphosphazene, poly(meth)acrylonitrile, ethylene propylene diene copolymer, polyvinylpyridine, chlorosulfonated polyethylene, latex, polyester resin, (meth)acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, and combinations thereof.

[0046] When the aqueous binder is used as a binder in the negative electrode active material layer AML2, the aqueous binder may further include a cellulose-based compound capable of imparting viscosity. As a cellulose-based compound, one or more types of carboxymethyl cellulose, hydroxypropyl methyl cellulose, methyl cellulose, and their alkali metal salts may be mixed and used. At least one of Na, K, and Li may be used as an alkali metal.

[0047] The dry binder is or includes a fibrous polymeric material, and may be or include at least one of, for example, polytetrafluoroethylene, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, and polyethylene oxide.

[0048] The conductive material imparts conductivity to the electrode, and any material can be used as long as it is conductive and does not cause adverse chemical changes in the battery to be formed. Examples of the conductive material include carbonaceous materials (such as at least one of natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, carbon fiber, carbon nanofiber, carbon nanotube, etc.); metallic materials in the form of metal powders or metal fibers containing at least one of copper, nickel, aluminum, silver, etc.; conductive polymers (such as polyphenylene derivatives, etc.); or mixtures thereof.

[0049] A current collector such as or including at least one of copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, and a polymer substrate coated with a conductive metal can be used as the negative electrode current collector COL2.

[0050] Negative electrode active material

[0051] The negative electrode active material in the negative electrode active material layer AML2 includes at least one of a material capable of reversibly intercalating / deintercalating lithium ions, lithium metal, an alloy of lithium and a metal, a material capable of doping and dedoping lithium, and a transition metal oxide.

[0052] The material capable of reversibly intercalating / deintercalating lithium ions may include carbonaceous negative electrode active materials, for example, crystalline carbon, amorphous carbon, or a combination thereof. Examples of crystalline carbon include graphite (such as amorphous, plate-like, flaky, spherical, or fibrous natural graphite or artificial graphite). Examples of amorphous carbon include at least one of soft carbon or hard carbon, mesophase pitch carbide, calcined coke, etc.

[0053] As the alloy of lithium and a metal, an alloy of lithium and a metal such as or including at least one of Na, K, Rb, Cs, Fr, Be, Mg, Ca, Sr, Si, Sb, Pb, In, Zn, Ba, Ra, Ge, Al, and Sn can be used.

[0054] As the material capable of doping and dedoping lithium, Si-based negative electrode active materials or Sn-based negative electrode active materials can be used. The Si-based negative electrode active material can be or include silicon, a silicon-carbon composite (Si-C composite), SiO x (0 < x ≤ 2, for example, SiO2) and a Si-Q alloy (where Q is or includes at least one of an alkali metal, an alkaline earth metal, a Group 13 element, a Group 14 element (excluding Si), a Group 15 element, a Group 16 element, a transition metal, and a rare earth element). The Sn-based negative electrode active material can be or include at least one of Sn, SnO k (0 < k ≤ 2, for example, SnO2) and Sn-based alloys.

[0055] The silicon-carbon composite may be or include a composite of silicon and amorphous carbon. According to one example embodiment, the silicon-carbon composite may be in the form of silicon particles (Si particles) with a surface coated with amorphous carbon. For example, the silicon-carbon composite may include secondary particles (cores) in which primary silicon particles are aggregated and an amorphous carbon coating (shell) disposed on the surface of the secondary particles. The amorphous carbon may also be located between the primary silicon particles; for example, the primary silicon particles may be coated with amorphous carbon. The secondary particles may be dispersed within an amorphous carbon matrix.

[0056] The silicon-carbon composite may further include crystalline carbon. For example, the silicon-carbon composite may include a core comprising crystalline carbon and silicon particles, and an amorphous carbon coating disposed on the surface of the core.

[0057] Si-based and / or Sn-based negative electrode active materials can be used in combination with carbon-based negative electrode active materials.

[0058] Diaphragm 30

[0059] Depending on the type of rechargeable lithium battery, the separator 30 may be present between the positive electrode 10 and the negative electrode 20. As the separator 30, a multilayer membrane consisting of at least one or two or more layers of polyethylene separator, polypropylene separator, and polyvinylidene fluoride separator may be used, such as a polyethylene / polypropylene two-layer separator, a polyethylene / polypropylene / polyethylene three-layer separator, a polypropylene / polyethylene / polypropylene three-layer separator, etc.

[0060] The diaphragm 30 may include a porous substrate and a coating, the coating comprising an organic material, an inorganic material, or a combination thereof, and disposed on one or both surfaces of the porous substrate.

[0061] The porous substrate may be or include a polymer membrane formed of any one of the following polymers or copolymers or mixtures thereof, or include any one of the following polymers or copolymers or mixtures thereof: polyolefins (such as polyethylene, polypropylene, etc.), polyesters (such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.), polyacetal, polyamide, polyimide, polycarbonate, polyetherketone, polyaryletherketone, polyetherimide, polyamideimide, polybenzimidazole, polyethersulfone, polyphenylene ether, cyclic olefin copolymers, polyphenylene sulfide, glass fiber, and at least one of polytetrafluoroethylene (e.g., Teflon).

[0062] Organic materials may include polymers such as polyvinylidene fluoride or (meth)acrylic acid polymers.

[0063] Inorganic materials may include inorganic particles such as at least one of Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2 and boehmite, or inorganic particles including at least one of Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2 and boehmite, but this disclosure is not limited thereto.

[0064] Organic and inorganic materials can exist as a mixture in a coating, or they can exist in the form of a coating that includes organic materials and a coating that includes inorganic materials laminated together.

[0065] Electrolyte ELL

[0066] Electrolytes used in rechargeable lithium batteries (ELL) consist of non-aqueous organic solvents and lithium salts.

[0067] Non-aqueous organic solvents constitute the medium through which ions participating in the electrochemical reactions in the battery can move.

[0068] The non-aqueous organic solvent may be or include at least one of carbonate solvents, ester solvents, ether solvents, ketone solvents, alcohol solvents, and aprotic solvents.

[0069] As a carbonate solvent, at least one of the following can be used: dimethyl carbonate (DMC), diethyl carbonate (DEC), dipropyl carbonate (DPC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), methyl ethyl carbonate (EMC), ethylene carbonate (EC), propylene carbonate (PC), and butyl carbonate (BC).

[0070] As an ester solvent, at least one of the following can be used: methyl acetate, ethyl acetate, n-propyl acetate, dimethyl acetate, methyl propionate, ethyl propionate, decanoic acid lactone, mevalonate lactone, caprolactone, etc.

[0071] As ether solvents, at least one of dibutyl ether, tetraethylene glycol dimethyl ether, diethylene glycol dimethyl ether, ethylene glycol dimethyl ether, 2-methyltetrahydrofuran, 2,5-dimethyltetrahydrofuran, tetrahydrofuran, etc., can be used. Cyclohexanone, etc., can be used as ketone solvents. Ethanol, isopropanol, etc., can be used as alcohol solvents. As a protic solvent, at least one of the following can be used: nitriles (such as R-CN, where R is a straight-chain, branched, or cyclic hydrocarbon group having 2 to 20 carbon atoms, and may include double bonds, aromatic rings, or ether bonds); amides (such as dimethylformamide); dioxolane (such as 1,3-dioxolane, 1,4-dioxolane); and sulfolane.

[0072] Non-aqueous organic solvents can be used alone or in combination with two or more solvents.

[0073] When using carbonate solvents, cyclic carbonates and chain carbonates can be used in combination, and cyclic carbonates and chain carbonates can be mixed in a volume ratio ranging from about 1:1 to about 1:9.

[0074] Lithium salts dissolve in non-aqueous organic solvents and thus constitute the source of lithium ions in the battery, allowing for the basic operation of rechargeable lithium batteries and facilitating the movement of lithium ions between the positive and negative electrodes. Representative examples of lithium salts may include LiPF6, LiBF4, LiSbF6, LiAsF6, LiClO4, LiAlO2, LiAlCl4, LiPO2F2, LiCl, LiI, LiN(SO3C2F5)2, Li(FSO2)2N (lithium bis(fluorosulfonyl)imide (LiFSI)), LiC4F9SO3, LiN(C x F 2x+1 SO2)(C y F 2y+1 One or more of the following: (SO2) (where x and y are integers in the range of 1 to 20), lithium trifluoromethanesulfonate (LiSO3CF3), lithium tetrafluoroethanesulfonate, lithium difluoro(oxalate)borate (LiDFOB), lithium difluorobis(oxalate)phosphate (LiDFBOP), lithium bis(oxalate)borate (LiBOB), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and lithium tetrafluorooxalate phosphate (LiTFOP).

[0075] Rechargeable lithium batteries

[0076] Rechargeable lithium batteries can be classified according to their type as cylindrical, prismatic, pouch, and coin-shaped batteries. Figures 2-5 A diagram illustrating a rechargeable lithium battery according to an example embodiment is shown. (See also...) Figure 2 , Figure 3 , Figure 4 and Figure 5 The figures show that rechargeable lithium batteries can be cylindrical, prismatic, and pouch-type. (Reference) Figures 2-5 The rechargeable lithium battery 100 may include an electrode assembly 40 having a separator 30 inserted between a positive electrode 10 and a negative electrode 20, and a housing 50 therein housing the electrode assembly 40. The positive electrode 10, negative electrode 20, and separator 30 may be impregnated with an electrolyte (not shown). Figure 2 As shown, the rechargeable lithium battery 100 may include a sealing member 60 configured as a sealed housing 50. (See diagram for reference.) Figure 3As shown, the rechargeable lithium battery 100 may include a positive electrode lead connector 11, a positive electrode terminal 12 connected to the positive electrode lead connector 11, a negative electrode lead connector 21, and a negative electrode terminal 22 connected to the negative electrode lead connector 21. Figure 4 and Figure 5 As shown, the rechargeable lithium battery 100 may include Figure 5 The electrode terminal 70 explained in the text, or Figure 4 The positive electrode terminal 71 and negative electrode terminal 72, as illustrated in the diagram, form an electrical path for guiding the current generated in the electrode assembly 40 to the outside of the battery 100.

[0077] The following describes in more detail a positive electrode slurry for a rechargeable lithium battery according to an exemplary embodiment of the present disclosure.

[0078] The positive electrode slurry for rechargeable lithium batteries includes a positive electrode active material, a binder, and a positive electrode additive, wherein the positive electrode additive includes an additive of the following chemical formula 1.

[0079] Chemical Formula 1:

[0080] .

[0081] In chemical formula 1,

[0082] R 1 and R 2 Each of these elements independently comprises or includes hydrogen, substituted or unsubstituted C1-C20 alkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C2-C20 alkynyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C6-C20 aryl, or substituted or unsubstituted C2-C20 heteroaryl.

[0083] R 3 and R 4 Each of these groups independently comprises or includes hydrogen, substituted or unsubstituted C1-C20 alkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C2-C20 alkynyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C6-C20 aryl, substituted or unsubstituted C2-C20 heteroaryl, or a group represented by the following chemical formula 1-1.

[0084] R 3 and R 4 At least one of them includes a group represented by chemical formula 1-1 (e.g., represented by chemical formula 1-1 below).

[0085] Chemical formula 1-1:

[0086] .

[0087] In chemical formula 1-1,

[0088] R 5 and R 6 Each of these elements independently comprises or includes a single bond, a substituted or unsubstituted C1-C20 alkylene group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C3-C20 cycloalkylene group, a substituted or unsubstituted C6-C20 aryl group, or a substituted or unsubstituted C2-C20 heteroaryl group. It refers to the part that is connected to N in chemical formula 1.

[0089] The additive of Formula 1 can provide a positive electrode that exhibits low gas generation rate, low resistance increase rate, and high open-circuit voltage (OCV) retention rate after storage at high voltage and high temperature. These characteristics are due to the formation of a substantially uniform and stable film on the surface of the positive electrode by the additive of Formula 1 during activation and operation of the rechargeable battery, but this disclosure is not limited thereto.

[0090] When applied to positive electrode slurries containing positive electrode active materials with high nickel content, the additive of Formula 1 can provide a positive electrode that offers low gas generation rate, low resistance increase rate, and high OCV retention rate even during high voltage and high temperature storage, without affecting the high energy density of the positive electrode active material.

[0091] In the example, R in chemical formula 1 3 and R 4 All of them may be groups represented by chemical formula 1-1. In this case, the compound represented by chemical formula 1 may have the following desired or improved effects: providing low gas generation rate, low resistance increase rate and high OCV retention rate during high voltage and high temperature storage in a positive electrode slurry comprising a positive electrode active material with a high nickel content.

[0092] In the example, in chemical formula 1-1, R 5 and R 6Each of these compounds may independently be or include substituted or unsubstituted C1-C20 alkylene groups, such as substituted or unsubstituted C1-C10 alkylene groups or substituted or unsubstituted C1-C5 alkylene groups, such as substituted or unsubstituted methylene, substituted or unsubstituted ethylene, substituted or unsubstituted linear or branched propylene, substituted or unsubstituted linear or branched butylene, or substituted or unsubstituted linear or branched pentylene. In this case, the compound represented by Formula 1 may have the desired or improved effect of providing low gas generation rate, low resistance increase rate, and high OCV retention rate during high voltage and high temperature storage in a positive electrode slurry comprising a positive electrode active material with a high nickel content.

[0093] R 1 and R 2 Each of these components may independently be or include hydrogen or substituted or unsubstituted C1-C20 alkyl groups, such as substituted or unsubstituted C1-C10 alkyl groups or substituted or unsubstituted C1-C5 alkyl groups, such as hydrogen, substituted or unsubstituted methyl groups, substituted or unsubstituted ethyl groups, substituted or unsubstituted straight-chain or branched propyl groups, substituted or unsubstituted straight-chain or branched butyl groups, or substituted or unsubstituted straight-chain or branched pentyl groups. In this case, the compound represented by Formula 1 may have the desired or improved effects of providing low gas generation rate, low resistance increase rate, and high OCV retention rate in positive electrode slurries comprising positive electrode active materials with high nickel content.

[0094] According to another exemplary embodiment of this disclosure, the compound represented by chemical formula 1 may be or include one or more of the compounds represented by chemical formulas 1-3 below.

[0095] Chemical formulas 1-3:

[0096] .

[0097] In chemical formulas 1-3,

[0098] R 1 and R 2 Each independently as defined in chemical formula 1,

[0099] R 7 and R 8 Each of these elements independently comprises or includes substituted or unsubstituted C1-C20 alkylene, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C2-C20 alkynyl, substituted or unsubstituted C3-C20 cycloalkylene, substituted or unsubstituted C6-C20 aryl, or substituted or unsubstituted C2-C20 heteroaryl.

[0100] In the example, in chemical formulas 1-3, R 7 and R 8 Each of these compounds may independently be or include substituted or unsubstituted C1-C20 alkylene groups, such as substituted or unsubstituted C1-C10 alkylene groups or substituted or unsubstituted C1-C5 alkylene groups, such as substituted or unsubstituted methylene, substituted or unsubstituted ethylene, substituted or unsubstituted linear or branched propylene, substituted or unsubstituted linear or branched butylene, or substituted or unsubstituted linear or branched pentylene. In this case, when applied to a positive electrode slurry comprising a positive electrode active material with a high nickel content, the compound represented by Formula 1 may have the desired or improved effects of providing low gas generation rate, low resistance increase rate, and high OCV retention rate.

[0101] In an example embodiment, the compound represented by chemical formula 1 may include one or more of the compounds represented by chemical formulas 1-4 to 1-10 below.

[0102] Chemical formulas 1-4:

[0103] ,

[0104] Chemical formulas 1-5:

[0105] ,

[0106] Chemical formulas 1-6:

[0107] ,

[0108] Chemical formulas 1-7:

[0109] ,

[0110] Chemical formulas 1-8:

[0111] ,

[0112] Chemical formulas 1-9:

[0113] ,

[0114] Chemical formulas 1-10:

[0115] .

[0116] Compounds represented by Formula 1 and those represented by Formulas 1-3 can be synthesized using conventional synthetic methods known to those skilled in the art. For example, the compound can be prepared using compounds providing a 4H-1,2,4-triazolyl and a CN-group.

[0117] Based on 100 parts by weight of the positive electrode active material, the additive of Formula 1 may be included in an amount ranging from about 0.1 parts by weight to about 10 parts by weight. The content of the additive of Formula 1 may be the content of the additive of Formula 1 in the positive electrode slurry based on the total weight of 100 parts by weight of the positive electrode active material in the positive electrode slurry. Within the above content range, a positive electrode that provides a low resistance increase rate and a low gas generation rate during high voltage and high temperature storage can be provided. For example, based on 100 parts by weight of the positive electrode active material, the additive of Formula 1 may be included in an amount ranging from about 0.1 parts by weight to about 5 parts by weight, about 0.1 parts by weight to about 3 parts by weight, or about 0.1 parts by weight to about 1 part by weight.

[0118] The positive electrode paste may include the above-mentioned lithium transition metal composite oxides as positive electrode active materials. That is, the positive electrode paste may include at least one of lithium nickel oxides, lithium cobalt oxides, lithium manganese oxides, lithium iron phosphate compounds, and cobalt-free nickel manganese oxides as positive electrode active materials.

[0119] In the example, the positive electrode slurry may include lithium nickel oxides. For example, lithium nickel oxides may be represented by the following chemical formula 2.

[0120] Chemical formula 2:

[0121] Li a1 Ni x1 M 1 y1 M 2 z1 O 2-b1 X b1 .

[0122] In chemical formula 2, 0.9 ≤ a1 ≤ 1.8, 0.3 ≤ x1 ≤ 1, 0 ≤ y1 ≤ 0.7, 0 ≤ z1 ≤ 0.7, 0.9 ≤ x1 + y1 + z1 ≤ 1.1, and 0 ≤ b1 ≤ 0.1, M 1 and M 2 Each of the following is independently one or more of Al, B, Ba, Ca, Ce, Co, Cr, Cu, Fe, Mg, Mn, Mo, Nb, Si, Sn, Sr, Ti, V, W, Y, and Zr, and X is one or more of F, P, and S.

[0123] In chemical formula 2, 0.6≤x1≤1, 0≤y1≤0.4, and 0≤z1≤0.4, or 0.8≤x1≤1, 0≤y1≤0.2, and 0≤z1≤0.2.

[0124] For example, the positive electrode active material may be or include high-nickel lithium nickel oxides, wherein the nickel content, based on 100 mol% of metals other than lithium in the lithium nickel oxide, is in the range of about 80 mol% or more, about 85 mol% or more, about 90 mol% or more, about 91 mol% or more, and about 99 mol% or less. High-nickel lithium nickel oxides can exhibit high capacity, thereby providing rechargeable lithium batteries with high capacity and high energy density.

[0125] In the example, lithium nickel oxides may be included in the range of about 95 wt% or more of the positive electrode active material (e.g., about 95 wt% to about 100 wt%, about 99 wt% to about 100 wt%, or about 100 wt%).

[0126] The binder may include one or more of the binders described for the positive electrode above.

[0127] In the examples, the adhesive may include fluorinated adhesives. For example, fluorinated adhesives may include fluorinated hydrocarbon resins. For example, fluorinated hydrocarbon resins may include at least one of polyvinylidene fluoride (PVDF), vinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), etc.

[0128] The positive electrode paste may further include conductive materials.

[0129] The conductive material may include one or more of the conductive materials described for the positive electrode above.

[0130] In the example, the conductive material may include one or more of artificial graphite and carbon black.

[0131] Based on a total of 100 parts by weight of positive electrode active material, conductive material and binder, the positive electrode paste may include approximately 90 parts by weight to approximately 99 parts by weight of positive electrode active material, approximately 0.5 parts by weight to approximately 5 parts by weight of conductive material and approximately 0.5 parts by weight to approximately 5 parts by weight of binder.

[0132] The positive electrode slurry may further include a dispersion medium.

[0133] The dispersion medium may include polar organic solvents, such as N-methyl-2-pyrrolidone.

[0134] The dispersion medium may be included in an amount ranging from about 15 wt% to about 30 wt% of the weight of the positive electrode slurry.

[0135] The solid content of the positive electrode paste can be in the range of approximately 70 wt% to 85 wt%.

[0136] The viscosity of the positive electrode slurry can be in the range of approximately 1,000 cP to approximately 10,000 cP. For example, the viscosity of the positive electrode slurry can be in the range of 1,000 cP to 5,000 cP or 2,000 cP to 4,000 cP. By controlling the amount of dispersion medium added during the manufacture of the positive electrode slurry, a slurry that meets this viscosity range can be prepared. When the positive electrode slurry meets this viscosity range, the positive electrode stabilizing effect of the positive electrode additive can be improved or maximized.

[0137] When the viscosity of the positive electrode slurry is within the above range, there will be no slurry loss when coating the positive electrode current collector with the slurry, and there will be no problem of excessive slurry coating or thickening of the positive electrode active material layer.

[0138] The viscosity of the positive electrode slurry can be measured at room temperature (25°C) using, for example, a Type B viscometer. However, the viscosity measuring device is not limited to the one described above, and any device capable of measuring the viscosity of liquids can be used without limitation.

[0139] The preparation of positive electrode slurry can be carried out by mixing positive electrode active material, binder, conductive material and compound represented by chemical formula 1 as positive electrode additive.

[0140] The following describes in more detail a positive electrode for a rechargeable lithium battery according to an exemplary embodiment of the present disclosure.

[0141] The positive electrode may include a layer of positive electrode active material made using a positive electrode slurry.

[0142] The positive electrode can be manufactured by preparing a positive electrode slurry, coating the positive electrode current collector with the positive electrode slurry, and forming a layer of positive electrode active material.

[0143] In another exemplary embodiment of this disclosure, a rechargeable lithium battery may include a positive electrode comprising a positive electrode active material and a negative electrode comprising a negative electrode active material, wherein the positive electrode may comprise a positive electrode made of a positive electrode slurry.

[0144] Rechargeable lithium batteries can be used in, for example, vehicles, mobile phones and / or various types of electronic devices, and this disclosure is not limited thereto.

[0145] Since the positive electrode has already been described above, a detailed description of the positive electrode slurry and the positive electrode itself is omitted.

[0146] In an example embodiment, the negative electrode active material may contain at least one of graphite and a Si composite.

[0147] When the negative electrode active material contains both a Si composite and graphite, the Si composite and graphite may be included in the form of a mixture, and in this case, based on a total of 100 parts by weight of the Si composite and graphite, the Si composite and graphite may be included at a weight ratio within the range of about 1:99 to about 50:50. For example, the Si composite and graphite may be included at a weight ratio within the range of about 3:97 to about 20:80, about 4:96 to about 20:80, or about 5:95 to about 20:80.

[0148] The Si composite includes a core containing Si-based particles and an amorphous carbon coating. For example, the Si-based particles may include one or more of a Si-C composite, SiO x (0 < x ≤ 2, for example, SiO2) and a Si alloy. For example, the Si-C composite may include a core containing Si particles and crystalline carbon and an amorphous carbon coating on the surface of the core. The crystalline carbon may include, for example, graphite, which may include, for example, natural graphite, artificial graphite, or a mixture thereof.

[0149] The rechargeable lithium battery may further include an electrolyte.

[0150] The electrolyte includes a non-aqueous organic solvent and a lithium salt.

[0151] The non-aqueous organic solvent may include one or more of the above non-aqueous organic solvents.

[0152] In one example, the non-aqueous organic solvent may be or include a mixture containing ethylene carbonate (EC): ethyl methyl carbonate (EMC): dimethyl carbonate (DMC) at a volume ratio within the range of about 10 to 30:10 to 30:40 to 80. Here, the volume ratio is a value based on a total of 100 volume% of ethylene carbonate (EC): ethyl methyl carbonate (EMC): dimethyl carbonate (DMC). Within the above range, the effects of the additives described below can be implemented, and in a rechargeable lithium battery including a positive electrode active material with a high nickel content described below, the battery life can be further increased under high voltage and high temperature conditions.

[0153] The lithium salt according to an exemplary embodiment of the present disclosure may include LiPF6, LiClO4, LiBF4, lithium bis(fluorosulfonyl)imide (LiFSI, Li(FSO2)2N), lithium bis(trifluoromethylsulfonyl)imide (LiTFSI), LiSO3CF3, LiBOB, LiDFOB, LiDFBOP, LiTFOP, LiPO2F2, LiSbF6, LiAsF6, LiAlO2, LiAlCl4, LiCl, LiI, LiN(SO3C2F5)2, LiN(C x F 2x+1 SO2)(C y F2y+1 One or more of SO2 (where x and y are integers in the range of 1 to 20) and LiC4F9SO3. According to one example embodiment, LiPF6 can be used as the lithium salt.

[0154] The concentration of the lithium salt can be in the range of about 0.1 M to about 3.0 M. For example, the concentration of the lithium salt can be about 0.5 M or higher, and can be about 1.0 M or higher. The concentration of the lithium salt can be about 3.0 M or lower, about 2.5 M or lower, or about 2.0 M or lower. In this disclosure, when the concentration of the lithium salt is in the range of about 0.1 M to about 2.0 M, the conductivity and viscosity of the electrolyte can be maintained as needed.

[0155] The following describes embodiments and comparative examples of this disclosure. However, the following examples are merely one exemplary implementation of this disclosure, and this disclosure is not limited to the following examples.

[0156] Examples and Comparative Examples

[0157] Example 1

[0158] (1) Preparation of additives for positive electrode paste

[0159] Add 8 g of NaOH to a round-bottom flask, add 50 g of distilled water, and stir the mixture at room temperature (23±2℃) for 30 minutes.

[0160] Add 8.41 g of 4-amino-1,2,4-triazole to the mixture and stir for another 30 minutes. Then slowly add 13.3 g of acrylonitrile dropwise to the reactants while keeping the internal temperature of the reactants below 40°C.

[0161] When a white solid is formed, the white solid is filtered through a filter and washed with water and ethanol, and then dried under vacuum to obtain the compound represented by the following chemical formulas 1-4 (400 MHz, DMSO-d6): δ 8.74 (s, 2H), 3.40-3.37 (m, 4H), 2.53-2.49 (m, 4H)).

[0162] Chemical formulas 1-4:

[0163] .

[0164] (2) Preparation of positive electrode paste

[0165] The positive electrode slurry was prepared by mixing 97.5 wt% LiNi 0.91 Co 0.08 Al 0.01O2, 0.5 wt% artificial graphite powder, 1 wt% carbon black (Ketjen black) and 1 wt% polyvinylidene fluoride (PVDF) were mixed with 0.5 wt% of the compound represented by chemical formulas 1-4 based on 100 wt% of the positive electrode active material. The mixture was then added to N-methyl-2-pyrrolidone (NMP) and stirred using a mechanical stirrer for 30 minutes.

[0166] (3) Preparation of rechargeable lithium batteries

[0167] The positive electrode was prepared by coating an aluminum current collector with a thickness of 20 µm to a thickness of 60 µm using a doctor blade, drying the aluminum current collector in a hot air dryer at 100 °C for 0.5 hours, drying the aluminum current collector again under vacuum at 120 °C for 4 hours, and then rolling the aluminum current collector.

[0168] The negative electrode active material slurry was prepared as follows: 98 wt% of a negative electrode active material containing a graphite and Si composite mixed in a weight ratio of 95.8:4.2, 1 wt% of styrene-butadiene rubber (SBR), and 1 wt% of carboxymethyl cellulose (CMC) were mixed, distilled water was added, and the mixture was stirred using a mechanical stirrer for 60 minutes. The negative electrode was prepared as follows: a copper current collector with a thickness of 10 µm was coated with the negative electrode active material slurry to a thickness of 60 µm using a doctor blade, the copper current collector was dried in a hot air dryer at 100 °C for 0.5 hours, dried again under vacuum at 120 °C for 4 hours, and then rolled.

[0169] Cylindrical rechargeable lithium batteries are prepared by assembling a positive electrode, a negative electrode, and a separator formed of or comprising polyethylene with a thickness of 16 µm to prepare an electrode assembly, and injecting an electrolyte into the electrode assembly. The electrolyte is prepared by dissolving and mixing 1.25 M LiPF6 in a carbonate solvent containing ethylene carbonate (EC): ethyl methyl carbonate (EMC): dimethyl carbonate (DMC) in a 20:30:50 volume ratio (volume ratio).

[0170] Example 2

[0171] The positive electrode slurry and rechargeable lithium battery were prepared by essentially the same method as in Example 1, except that in Example 1, 100 parts by weight of the positive electrode active material included compounds represented by chemical formulas 1-4 in an amount of 1 part by weight.

[0172] Example 3

[0173] The positive electrode slurry and rechargeable lithium battery were prepared by essentially the same method as in Example 1, except that in Example 1, 2 parts by weight of compounds represented by chemical formulas 1-4 were included based on 100 parts by weight of the positive electrode active material.

[0174] Example 4

[0175] The positive electrode slurry and rechargeable lithium battery were prepared by essentially the same method as in Example 1, except that in Example 1, based on 100 parts by weight of the positive electrode active material, 5 parts by weight of compounds represented by chemical formulas 1-4 were included.

[0176] Comparative Example 1

[0177] The positive electrode slurry and rechargeable lithium battery were prepared by essentially the same method as in Example 1, except that they did not contain the compounds represented by chemical formulas 1-4 as in Example 1.

[0178] Evaluation Example

[0179] The following methods were used to evaluate rechargeable lithium batteries.

[0180] Evaluation Example 1: High-Temperature Storage Characteristics Evaluation (Increase in Cell Thickness)

[0181] For the rechargeable lithium batteries according to the embodiments and comparative examples, the cell thickness increase rate was measured to evaluate the high-temperature gas generation characteristics. The thickness of the initial cell (initial thickness of the cell or thickness of the cell after 0 days) and the thickness of the cell after 28 days of storage at 60°C (thickness of the cell after 28 days) were measured, and the thickness increase rate was calculated. The thickness increase rate was calculated according to the following equation.

[0182] equation:

[0183] Thickness increase rate (%) = [(thickness of the battery cell after 28 days of storage at 60°C) / (initial thickness of the battery cell)] × 100.

[0184] Specifically, the thickness of the battery cell was measured using a Mitutoyo compression thickness measuring device while the battery cell was located between compression plates and compressed to a weight of 300g.

[0185] Evaluation Example 2: High-Temperature Storage Characteristics Evaluation (OCV Retention Rate)

[0186] For the rechargeable lithium batteries according to the embodiments and comparative examples, the initial OCV (OCV on day 0) was measured after charging at 0.5 CC / CV (4.4 V 0.05 C cutoff), and the OCV (OCV on day 28) was measured after storage at 60°C for 28 days. δOCV (ΔOCV) was then calculated from these values ​​(i.e., ΔOCV = OCV on day 0 - OCV on day 28). A smaller ΔOCV value indicates that capacity retention is desirable or has been improved.

[0187] Evaluation Example 3: High-Temperature Storage Characteristics Evaluation (DCIR Increase Rate)

[0188] For the rechargeable lithium battery according to the embodiments and comparative examples, the ΔV / ΔI (voltage change / current change) value is measured as the initial DC internal resistance (initial DCIR or DCIR after 0 days). Then, the maximum energy state inside the rechargeable lithium battery is made to a fully charged state (SOC 100%). In this state, the rechargeable lithium battery is stored at 60°C for 60 days. Then, the DC internal resistance (DCIR after 60 days) is measured, and the DCIR increase rate (%) is calculated according to the following equation.

[0189] equation:

[0190] DCIR increase rate (%) = (DCIR after 60 days / initial DCIR) × 100.

[0191] The results of evaluation examples 1 to 3 are shown in Table 1 below.

[0192] Table 1:

[0193]

[0194] In Table 1,

[0195] content Content of compounds (parts by weight) based on 100 parts by weight of the positive electrode active material.

[0196] in conclusion

[0197] Referring to Table 1, based on the results of Evaluation Examples 1 to 3, the following conclusion can be drawn: even when high-nickel positive electrode active materials are included, rechargeable lithium batteries having a positive electrode manufactured using the positive electrode slurry of the examples can improve lifespan and performance at high temperatures.

[0198] However, referring to Table 1, based on the results of Evaluation Examples 1 to 3, in Comparative Example 1, which does not include the compound represented by Chemical Formula 1 of this disclosure, the effect of improving lifespan and performance at high temperatures is not significant even when the rechargeable lithium battery includes a high-nickel positive electrode active material.

[0199] In a positive electrode slurry for a rechargeable lithium battery according to an example embodiment, when the rechargeable lithium battery is activated during high-voltage and high-temperature storage, the characteristics and stability of the rechargeable lithium battery can be improved by providing a positive electrode with a low gas generation rate, a low resistance increase rate, and a high open-circuit voltage (OCV) retention rate.

[0200] Although exemplary embodiments of the present disclosure have been described above, the present disclosure is not limited thereto, and modifications may be made in any form within the scope of the claims, the detailed description of the present disclosure and the accompanying drawings, and such modifications also fall within the scope of the present disclosure.

Claims

1. A positive electrode slurry for a rechargeable lithium battery, the positive electrode slurry comprising: Positive electrode active material; Adhesives; and Positive electrode additive, The positive electrode additive mentioned above comprises a compound represented by chemical formula 1: Chemical Formula 1: ； in: R 1 and R 2 Each of these elements independently includes hydrogen, substituted or unsubstituted C1-C20 alkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C2-C20 alkynyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C6-C20 aryl, or substituted or unsubstituted C2-C20 heteroaryl. R 3 and R 4 Each of these groups independently comprises hydrogen, substituted or unsubstituted C1-C20 alkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C2-C20 alkynyl, substituted or unsubstituted C3-C20 cycloalkyl, substituted or unsubstituted C6-C20 aryl, substituted or unsubstituted C2-C20 heteroaryl, or a group represented by formula 1-1. R 3 and R 4 At least one of them includes a group represented by the chemical formula 1-1: Chemical formula 1-1: ； in: R 5 and R 6 Each independently comprises a single bond, a substituted or unsubstituted C1-C20 alkylene group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 ynynyl group, a substituted or unsubstituted C3-C20 cycloalkylene group, a substituted or unsubstituted C6-C20 aryl group, or a substituted or unsubstituted C2-C20 heteroaryl group, and Refers to the part that connects to N in chemical formula 1.

2. The positive electrode paste according to claim 1, wherein the compound represented by chemical formula 1 is represented by chemical formulas 1-3: Chemical formulas 1-3: ； in: R 1 and R 2 Each is independently defined as in chemical formula 1, and R 7 and R 8 Each of these independently includes substituted or unsubstituted C1-C20 alkylene, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C2-C20 alkynyl, substituted or unsubstituted C3-C20 cycloalkylene, substituted or unsubstituted C6-C20 aryl, or substituted or unsubstituted C2-C20 heteroaryl.

3. The positive electrode paste according to claim 1, wherein the compound represented by chemical formula 1 includes one or more compounds represented by chemical formulas 1-4 to 1-10: Chemical formulas 1-4: ； Chemical formulas 1-5: ； Chemical formulas 1-6: ； Chemical formulas 1-7: ； Chemical formulas 1-8: ； Chemical formulas 1-9: ;and Chemical formulas 1-10: 。 4. The positive electrode slurry of claim 1, wherein the compound represented by chemical formula 1 is included in an amount ranging from 0.1 parts by weight to 10 parts by weight based on 100 parts by weight of the positive electrode active material.

5. The positive electrode slurry of claim 1, wherein the positive electrode active material comprises lithium nickel oxide, and the lithium nickel oxide has a nickel content of 80 mol% or more, based on 100 mol% of metals other than lithium in the lithium nickel oxide.

6. The positive electrode slurry of claim 1, wherein the positive electrode active material comprises lithium nickel oxide, and the lithium nickel oxide is represented by chemical formula 2: Chemical formula 2: Li a1 Ni x1 M 1 y1 M 2 z1 O 2-b1 X b1 ; in: 0.9≤a1≤1.8, 0.6≤x1≤1, 0≤y1≤0.4, 0≤z1≤0.4, 0.9≤x1+y1+z1≤1.1, and 0≤b1≤0.

1. M 1 and M 2 Each independently includes one or more of Al, B, Ba, Ca, Ce, Co, Cr, Cu, Fe, Mg, Mn, Mo, Nb, Si, Sn, Sr, Ti, V, W, Y, and Zr, and X includes one or more of F, P, and S.

7. The positive electrode slurry of claim 5, wherein the lithium nickel oxide comprises 95 wt% or more of the positive electrode active material.

8. The positive electrode paste of claim 1, wherein the binder comprises a fluorinated binder.

9. The positive electrode paste of claim 1, wherein the positive electrode paste further comprises one or more conductive materials selected from carbon black and artificial graphite.

10. The positive electrode paste of claim 9, wherein the positive electrode paste comprises, based on a total of 100 parts by weight of the positive electrode active material, the conductive material, and the binder, the positive electrode paste includes: The positive electrode active material is in the range of 90 parts by weight to 99 parts by weight; The conductive material is present in the range of 0.5 parts by weight to 5 parts by weight; and The adhesive is in the range of 0.5 parts by weight to 5 parts by weight.

11. The positive electrode slurry as described in claim 1 or 9, further comprising a dispersion medium. The dispersion medium is included in an amount ranging from 15 wt% to 30 wt% of the weight of the positive electrode slurry, and The solid content of the positive electrode slurry ranges from 70 wt% to 85 wt%.

12. A rechargeable lithium battery, comprising: Positive electrode; and The negative electrode, including the negative electrode active material, The positive electrode is manufactured using the positive electrode paste as described in any one of claims 1 to 11.

13. The rechargeable lithium battery of claim 12, wherein the negative electrode active material comprises at least one of graphite and Si composite.

14. The rechargeable lithium battery of claim 12, wherein the rechargeable lithium battery is a cylindrical battery, a prismatic battery, a pouch battery, or a coin-shaped battery.

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