Positive electrode active material composition, positive electrode sheet, secondary battery, power using device

Abstract

The present application relates to a positive electrode active material composition, a positive electrode sheet, a secondary battery, and a power using device. The positive electrode active material composition includes: a ternary material and a lithiated organic material; the chemical formula of the ternary material is LiNi x Co y Mn z O2, wherein, 0

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and particularly to a positive electrode active material composition, a positive electrode sheet, a secondary battery, and an electrical device. Background Art

[0002] In recent years, with the increasingly wide application range of lithium-ion batteries, lithium-ion batteries are widely used in energy storage power systems such as hydraulic, thermal, wind, and solar power stations, as well as in multiple fields such as power tools, electric bicycles, electric motorcycles, electric vehicles, military equipment, and aerospace. Among them, ternary materials, as positive electrode materials, can meet the performance requirements such as long life and low-temperature discharge of lithium-ion batteries, and have gradually received extensive attention.

[0003] However, the energy density of ternary batteries with ternary materials as positive electrode materials needs to be improved. In addition, ternary materials are prone to side reactions during cycling to generate gas, increasing the risk of battery thermal runaway. Summary of the Invention

[0004] Based on this, it is necessary to provide a positive electrode active material composition, a positive electrode sheet, a secondary battery, and an electrical device to improve the energy density of ternary batteries, reduce gas production, improve interfacial stability, and thus improve the cycle performance of the batteries.

[0005] The first aspect of the present application provides a positive electrode active material composition, which includes: a ternary material and a lithiated organic material; the chemical formula of the ternary material is LiNi x Co y Mn z O2, where 0 < x < 1, 0 < y < 1, 0 < z < 1, and x + y + z = 1; the chemical formula of the lithiated organic material is LiX, where X is selected from at least one of the compounds having the structural formulas shown in Formulas (I) to (V):

[0006]

[0007]

[0008] In some embodiments, the mass ratio of the ternary material to the lithiated organic material is (99:1) to (75:25).

[0009] In some embodiments, LiX is obtained by a lithiation reaction of X and a lithiating agent.

[0010] In some embodiments, the lithiating agent is selected from one or more of LiOH, LiNO3, and Li2CO₃.

[0011] In some embodiments, the precursor compound of X is pyrene-4,5,9,10-tetrone.

[0012] A second aspect of this application provides a positive electrode sheet, which includes: a positive current collector; and a positive active material layer disposed on at least one side of the surface of the positive current collector, the positive active material layer including the positive active material composition provided in the first aspect.

[0013] A third aspect of this application provides a secondary battery comprising the positive electrode provided in the second aspect above.

[0014] In some implementations, the secondary battery is a solid-state battery, which includes a solid electrolyte membrane.

[0015] In some embodiments, the solid electrolyte membrane includes at least one of oxide solid electrolyte, polymer solid electrolyte, and halide solid electrolyte.

[0016] The fourth aspect of this application provides an electrical device that includes the secondary battery provided in the third aspect above.

[0017] Compared with traditional technologies, this application has at least the following beneficial effects:

[0018] The positive electrode active material composition provided in this application, through the synergistic effect of ternary materials and lithium-ionized organic materials, achieves several advantages. On the one hand, the lithium-ionized organic material has a large π-π conjugated structure with multiple electron centers, which enhances electronic conductivity. Furthermore, the nitrogen atoms in the lithium-ionized organic material have lone pairs of electrons, which can serve as active sites for redox reactions. The alternating distribution of active sites in the lithium-ionized organic material reduces steric hindrance and improves the energy density of the ternary battery. On the other hand, the large π-π conjugated structure of the lithium-ionized organic material results in weak intermolecular interactions, which can adsorb gases generated during the cycling and storage of the ternary material, thereby reducing the risk of battery swelling. The large π-π conjugated structure also helps to improve the thermal stability of the material, reduce the risk of battery thermal runaway, and improve the safety performance of the battery. Moreover, the flexibility of the lithium-ionized organic material means that the volume and structural changes of the material are not significant after ion insertion / extraction, which helps to alleviate interfacial stress and thus improve the cycle performance of the battery. Detailed Implementation

[0019] Reference will now be made to detailed embodiments of this application, one or more of which are described below. Each example is provided for explanation and not for limitation of this application. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made to this application without departing from its scope or spirit. For example, features described or illustrated as part of one embodiment may be used in another embodiment to produce further embodiments.

[0020] Therefore, this application is intended to cover such modifications and variations falling within the scope of the appended claims and their equivalents. Other objects, features, and aspects of this application are disclosed in or will be apparent from the following detailed description. It will be understood by those skilled in the art that this discussion is merely a description of exemplary embodiments and is not intended to limit the broader aspects of this application.

[0021] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0022] In this application, numerical ranges are referred to as continuous unless otherwise specified, and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0023] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0024] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0025] Unless otherwise specified, all steps of this application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order; for example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0026] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0027] Unless otherwise specified, the term "or" is inclusive in this application. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or present) and B is false (or absent); A is false (or absent) while B is true (or present); or both A and B are true (or present).

[0028] The first aspect of this application provides a cathode active material composition, which includes a ternary material and a lithiated organic material. The chemical formula of the ternary material is LiNi x Co y Mn z O2, where 0 < x < 1, 0 < y < 1, 0 < z < 1, and x + y + z = 1. The chemical formula of the lithiated organic material is LiX, where X is selected from at least one of the compounds having the structural formulas shown in Formulas (I) to (V):

[0029]

[0030]

[0031] For the cathode active material composition provided by this application, through the synergistic effect of the ternary material and the lithiated organic material, on the one hand, the lithiated organic material has a large π-π conjugated structure with multiple electron centers, enhancing the electronic conductivity. And the nitrogen atoms in the lithiated organic material have lone pairs of electrons, which can serve as active sites for redox reactions. The active sites of the lithiated organic material are alternately distributed, reducing steric hindrance and improving the energy density of the battery. On the other hand, the large π–π conjugated structure of the lithiated organic material enables weak intermolecular interactions, which can adsorb the gases generated during the cycling and storage of the ternary material, thereby reducing the risk of battery swelling. The large π–π conjugated structure is also beneficial to improving the thermal stability of the material, reducing the risk of battery thermal runaway, and improving the safety performance of the battery. The flexibility of the lithiated organic material makes the volume and structure of the material change insignificantly after ion insertion / extraction, which is beneficial to alleviating the interfacial stress and thus improving the cycling performance of the battery.

[0032] In some of these embodiments, the mass ratio of the ternary material to the lithiated organic material is (99:1) to (75:25). Within the above mass ratio range, it is possible to improve the energy density, safety performance, and cycling stability of the battery while ensuring a high energy density of the battery.

[0033] In some of these embodiments, LiX is obtained by a lithiation reaction of X with a lithiating agent. The lithiation reaction introduces lithium ions at the active sites in X, making LiX capable of serving as a lithium source to provide lithium ions for the electrode and also directly participating in the electrochemical reaction, thereby enhancing the specific capacity of the cathode material.

[0034] In some embodiments, the lithiating agent is selected from one or more of LiOH, LiNO3, and Li2CO3.

[0035] In some embodiments, the precursor compound of X is pyrene-4,5,9,10-tetraone. Pyrene-4,5,9,10-tetraone is a highly conjugated polycyclic compound. As a precursor of X, it can introduce side chains by reacting with ortho-amino compounds, regulating the side chains to have alternating active sites, thereby obtaining compound X with multiple electron centers and a large π-π conjugated structure.

[0036] A second aspect of this application provides a positive electrode sheet comprising a positive current collector and a positive active material layer. The positive active material layer is disposed on at least one surface of the positive current collector, and the positive active material layer comprises the positive active material composition provided in the first aspect.

[0037] In some embodiments, the positive current collector is selected from metal foil or composite current collector; the composite current collector has a sandwich-like sandwich structure, with the middle polymer layer mainly composed of materials such as high-molecular insulating resin, and metal layers deposited on both sides of the middle polymer layer by electroplating, chemical plating, or other methods. Schematic, the high-molecular resin includes polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyetheretherketone, polyimide, polyamide, polyethylene glycol, polyamide-imide, polycarbonate, and cyclic resins. The material is selected from one or more of the following: polyolefins, polyphenylene sulfide, polyvinyl acetate, polytetrafluoroethylene, polymethylene naphthalene, polyvinylidene fluoride, polyethylene naphthalate, polypropylene carbonate, poly(vinylidene fluoride-hexafluoropropylene), poly(vinylidene fluoride-co-trifluorochloroethylene), silicone, vinylon, polypropylene, polyethylene, polyvinyl chloride, polystyrene, polyether nitrile, polyurethane, polyphenylene ether, polyester, polysulfone and its derivatives, sodium carboxymethyl cellulose, styrene-butadiene rubber, fluorinated rubber, polyvinyl alcohol, or polyvinylidene fluoride. The metal layer is selected from at least one of aluminum, copper, nickel, cobalt, tungsten, tin, lead, iron, silver, or gold. Further, the positive current collector is aluminum foil.

[0038] In some embodiments, the positive electrode active material layer also includes a conductive agent, which plays a role in collecting microcurrents between the positive electrode active materials and between the positive electrode active materials and the positive electrode current collector.

[0039] In some embodiments, the conductive agent accounts for 1% to 10% of the mass of the positive electrode active material layer.

[0040] In some embodiments, the conductive agent includes graphite, such as natural or artificial graphite; carbon materials, such as carbon black, acetylene black, Ketjen black, channel black, super-P, and thermally cracked black; conductive fibers, such as carbon fibers and metal fibers; conductive tubes, such as carbon nanotubes; metal powders, such as fluorocarbon powders, aluminum powders, and nickel powders; conductive whiskers, such as zinc oxide and potassium titanate; conductive metal oxides, such as titanium oxides; and polyphenylene derivatives, and super-P is preferably preferred for improving conductivity.

[0041] In some embodiments, the specific surface area of ​​the conductive agent can be 80 m². 2 / g~200m 2 / g, preferably 100m 2 / g~150m 2 / g.

[0042] In some embodiments, the positive electrode active material layer also includes a binder, which can serve to bond the positive electrode active material and the conductive agent together; the binder accounts for 1% to 10% of the mass of the positive electrode active material layer.

[0043] In some embodiments, the thickness of the positive electrode active material layer can be 30μm to 400μm, for example 30μm, 40μm, 50μm, 80μm, 110μm, 200μm, 300μm, 400μm, preferably 50μm to 110μm.

[0044] In some embodiments, the secondary battery further includes a negative electrode sheet. The negative electrode active material layer includes at least a negative electrode active material.

[0045] In some embodiments, the negative electrode active material in this application is not particularly limited, as long as it is a substance that can electrochemically absorb and release s-region metal ions such as lithium ions, sodium ions, potassium ions, and magnesium ions, such as carbonaceous materials, metal compound materials, or their oxides, carbides, nitrides, silicides, sulfides, phosphides, etc. These substances can be used alone, or two or more can be used in combination at will.

[0046] In some embodiments, carbon materials can be selected as the negative electrode active material, specifically one or more of the following: graphite, needle coke, amorphous carbon, carbon-containing mesophase, carbon fiber, and carbon materials with low graphitization. Graphite can include natural graphite, artificial graphite, etc. Alternatively, materials obtained by coating these materials with carbon materials, such as amorphous carbon or graphitides, can also be used. Amorphous carbon includes, but is not limited to, particles obtained by sintering a monolithic mesophase, and particles obtained by sintering a carbon precursor after a non-melting treatment. Examples of carbonaceous particles with low graphitization include particles obtained by sintering organic matter at temperatures typically below 2500°C.

[0047] In some embodiments, non-metallic materials that can be used as negative electrode active materials also include elemental silicon and its compounds, such as Si and SiO. x (0≤x<2), because silicon-containing materials are prone to expansion and easy to fall off from the negative electrode current collector, and have poor conductivity, they are often used in combination with carbon materials, such as core-shell structures containing carbon coating layers.

[0048] In some embodiments, elemental metals and metal compounds can also be selected as negative electrode active materials, such as compounds containing metals or metalloids such as Li, Ag, Al, Bi, Cu, Ga, Ge, In, Ni, Pb, Sb, Si, Sn, Sr, and Zn.

[0049] A third aspect of this application provides a secondary battery comprising the positive electrode provided in the second aspect above.

[0050] In some embodiments, the secondary battery is a solid-state battery, which includes a solid electrolyte membrane. The ternary material is an inorganic rigid material, and the lithium-ionized organic material is a flexible material. The lithium-ionized organic material is adsorbed onto the surface of the ternary particulate material via van der Waals forces, which can construct new ion / electron pathways, optimize the interface between the positive electrode and the solid electrolyte, and reduce the interfacial impedance of the solid-state battery. Therefore, the positive electrode active material composition provided in this application is particularly suitable for solid-state batteries.

[0051] In some embodiments, the solid electrolyte membrane includes at least one of oxide solid electrolyte, polymer solid electrolyte, and halide solid electrolyte.

[0052] In some embodiments, the oxide solid electrolyte includes at least one of garnet-type lithium lanthanum zirconium oxide (LLZO), NASICON type, and LISICON type.

[0053] NASICON type oxide solid electrolyte is AM′M″P3O 12The molecular formula of sodium superionic conductor typically represents a monovalent transport cation, such as at least one alkali metal ion from Na, K, or Li. The M′ and M″ positions can be occupied by either divalent or trivalent cations (e.g., Zn). 2+ Mg 2+ Ni 2+ Cr 3+ Al 3+ ,Sc 3+ Fe 3+ In 3+ and Y 3+ It can be at least one of the following), or a tetravalent or pentavalent cation (e.g., it may include Ti). 4+ Zr 4+ 、Ge 4+ Sn 4+ V 5+ 、Nb 5+ As 5+ (at least one of the following). Furthermore, P 5+ It can also be affected by other high-valence ions such as Si. 4+ V 5+ 、Nb 5+ Doping or substitution. Exemplarily, this NASICON-type oxide solid electrolyte can be, but is not limited to, Na3Zr2Si2PO4. 12 .

[0054] LISICON-type oxide solid electrolytes are lithium-ion conductors containing a robust three-dimensional anionic framework. The framework ions provide transport channels for migratable lithium ions. In addition to the framework, Li... + Located in interstitial positions, these lithium ions are mobile and conductive, exhibiting good proton exchange capabilities. In the exemplary example, this LISICON-type oxide solid-state electrolyte can be, but is not limited to, Li... 4-x Ge 1-x P x S4, where x can be 0.01 to 0.99. In the example, the value of x can be typical but not restrictive values ​​such as 0.01, 0.05, 0.1, 0.5, 0.75, 0.9, and 0.99.

[0055] In some embodiments, the polymer solid electrolyte is selected from one or more of the following: polyacrylonitrile (PAN), polyethylene oxide (PEO), polysiloxane (PSO), polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polymethyl methacrylate (PMMA), and derivatives thereof.

[0056] In some embodiments, the halide solid electrolyte includes LiaMY4, LiaMY6 and LiaMY8, wherein M may include at least one of metals such as Mn, Zn, Fe, Al, Yb, etc., and Y may include at least one of halogens such as F, Cl, Br, I.

[0057] The fourth aspect of this application provides an electrical device that includes the secondary battery provided in the third aspect above.

[0058] The electrical device used in this application is not particularly limited and can be any electrical device known in the prior art. For example, the electrical device may include, but is not limited to, laptops, pen input computers, mobile computers, e-book players, portable telephones, portable fax machines, portable copiers, portable printers, stereo headphones, video recorders, LCD TVs, portable cleaners, portable CD players, mini CDs, transceivers, electronic notebooks, calculators, memory cards, portable recorders, radios, backup power supplies, motors, automobiles, motorcycles, electric bicycles, bicycles, lighting fixtures, toys, game consoles, clocks, power tools, flashlights, cameras, household large-capacity batteries, and lithium-ion capacitors.

[0059] The present application will be further described below with reference to specific preparation examples, embodiments and comparative examples.

[0060] Preparation Example 1

[0061] This preparation example provides a method for preparing lithium-ionized organic materials.

[0062] S1. Weigh 13g of pyrene-4,5,9,10-tetraone and 25g of 6,7-quinoxaline diamine, add them to 300mL of a mixed solvent of acetic acid and ethanol (1:1), and heat to 120℃ to react. After the reaction is completed, filter, wash and dry to obtain the compound shown in formula (Ⅰ).

[0063]

[0064] S2. The compound shown in formula (Ⅰ) above is added to the lithiation agent LiOH to carry out the lithiation reaction. After the reaction is completed, the mixture is washed and dried to obtain the lithified organic material.

[0065] Preparation Example 2

[0066] The preparation method of the lithium-ionized organic material in this preparation example is basically the same as that in Preparation Example 1, except that:

[0067] In step S1, o-diaminobenzene is replaced with 5,6-quinoxaline diamine to obtain the compound shown in formula (II).

[0068]

[0069] Preparation Example 3

[0070] The preparation method of the lithium-ionized organic material in this preparation example is basically the same as that in Preparation Example 1, except that:

[0071] In step S1, o-diaminobenzene is replaced with the compound shown in formula (VI) to obtain the compound shown in formula (III).

[0072]

[0073] Preparation Example 4

[0074] The preparation method of the lithium-ionized organic material in this preparation example is basically the same as that in Preparation Example 1, except that:

[0075] In step S1, o-diaminobenzene is replaced with 2,3-diaminophenolazine to obtain the compound shown in formula (Ⅳ).

[0076]

[0077] Preparation Example 5

[0078] The preparation method of the lithium-ionized organic material in this preparation example is basically the same as that in Preparation Example 1, except that:

[0079] In step S1, o-diaminobenzene is replaced with the compound shown in formula (VII) to obtain the compound shown in formula (V).

[0080]

[0081] Example 1

[0082] Positive electrode active material composition:

[0083] Ternary material LiNi 0.83 Co 0.12 Mn 0.05 O2 and the lithium-ionized organic material prepared in Example 1, wherein the mass ratio of the ternary material to the lithium-ionized organic material is 85:15.

[0084] Positive electrode sheet:

[0085] A positive electrode slurry was prepared by adding a positive electrode active material composition, conductive carbon black (Super-P) as a conductive agent, and polyvinylidene fluoride (PVDF) as a binder in a mass ratio of 96:3:1 to a solvent N-methylpyrrolidone (NMP). The positive electrode slurry was then coated onto a 13 μm thick aluminum foil for the positive electrode current collector and dried to form a positive electrode active material layer, thus obtaining the positive electrode sheet.

[0086] Secondary batteries:

[0087] The secondary battery in this embodiment is a solid-state battery. The solid electrolyte membrane includes a PEO polymer solid electrolyte. The negative electrode of the solid-state battery is a lithium metal negative electrode.

[0088] Example 2

[0089] The preparation methods of the positive electrode active material composition, positive electrode sheet, and secondary battery in this embodiment are basically the same as those in Example 1, except that:

[0090] The lithium-ionized organic material in the positive electrode active material composition is the lithium-ionized organic material prepared in Preparation Example 2.

[0091] Example 3

[0092] The preparation methods of the positive electrode active material composition, positive electrode sheet, and secondary battery in this embodiment are basically the same as those in Example 1, except that:

[0093] The lithium-ionized organic material in the positive electrode active material composition is the lithium-ionized organic material prepared in Preparation Example 3.

[0094] Example 4

[0095] The preparation methods of the positive electrode active material composition, positive electrode sheet, and secondary battery in this embodiment are basically the same as those in Example 1, except that:

[0096] The lithium-ionized organic material in the positive electrode active material composition is the lithium-ionized organic material prepared in Preparation Example 4.

[0097] Example 5

[0098] The preparation methods of the positive electrode active material composition, positive electrode sheet, and secondary battery in this embodiment are basically the same as those in Example 1, except that:

[0099] The lithium-ionized organic material in the positive electrode active material composition is the lithium-ionized organic material prepared in Preparation Example 5.

[0100] Example 6

[0101] The preparation methods of the positive electrode active material composition, positive electrode sheet, and secondary battery in this embodiment are basically the same as those in Example 1, except that:

[0102] The mass ratio of ternary material to lithium-ionized organic material in the positive electrode active material composition is 95:5.

[0103] Example 7

[0104] The preparation methods of the positive electrode active material composition, positive electrode sheet, and secondary battery in this embodiment are basically the same as those in Example 1, except that:

[0105] The mass ratio of ternary material to lithium-ion organic material in the positive electrode active material composition is 80:20.

[0106] Example 8

[0107] The preparation methods of the positive electrode active material composition, positive electrode sheet, and secondary battery in this embodiment are basically the same as those in Example 1, except that:

[0108] The mass ratio of ternary material to lithium-ionized organic material in the positive electrode active material composition is 70:30.

[0109] Comparative Example 1

[0110] Positive electrode active material:

[0111] Ternary material LiNi 0.83 Co 0.12 Mn 0.05 O2.

[0112] Positive electrode sheet:

[0113] A positive electrode slurry was prepared by adding positive electrode active material, conductive carbon black (Super-P) and binder polyvinylidene fluoride (PVDF) in a mass ratio of 96:3:1 to solvent N-methylpyrrolidone (NMP). The positive electrode slurry was then coated onto a 13 μm thick aluminum foil for positive electrode current collector and dried to form a positive electrode active material layer, thus obtaining the positive electrode sheet.

[0114] Secondary batteries:

[0115] The secondary battery in this comparative example is a solid-state battery. The solid electrolyte membrane includes a PEO polymer solid electrolyte. The negative electrode of the solid-state battery is a lithium metal negative electrode.

[0116] Comparative Example 2

[0117] Positive electrode active material:

[0118] The lithium-ionized organic material prepared in Example 1.

[0119] Positive electrode sheet:

[0120] A positive electrode slurry was prepared by adding positive electrode active material, conductive carbon black (Super-P) and binder polyvinylidene fluoride (PVDF) in a mass ratio of 96:3:1 to solvent N-methylpyrrolidone (NMP). The positive electrode slurry was then coated onto a 13 μm thick aluminum foil for positive electrode current collector and dried to form a positive electrode active material layer, thus obtaining the positive electrode sheet.

[0121] Secondary batteries:

[0122] The secondary battery in this comparative example is a solid-state battery. The solid electrolyte membrane includes a PEO polymer solid electrolyte. The negative electrode of the solid-state battery is a lithium metal negative electrode.

[0123] Comparative Example 3

[0124] Positive electrode active material composition:

[0125] LiNi 0.83 Co 0.12 Mn 0.05 O2 and lithium-ion organic materials, wherein the mass ratio of ternary material to lithium-ion organic materials is 85:15, and the chemical formula of lithium-ion organic materials is LiN, where N is a compound having the chemical formula shown in formula (VIII).

[0126]

[0127] Positive electrode sheet:

[0128] A positive electrode slurry was prepared by adding a positive electrode active material composition, conductive carbon black (Super-P) as a conductive agent, and polyvinylidene fluoride (PVDF) as a binder in a mass ratio of 96:3:1 to a solvent N-methylpyrrolidone (NMP). The positive electrode slurry was then coated onto a 13 μm thick aluminum foil for the positive electrode current collector and dried to form a positive electrode active material layer, thus obtaining the positive electrode sheet.

[0129] Secondary batteries:

[0130] The secondary battery in this comparative example is a solid-state battery. The solid electrolyte membrane includes a PEO polymer solid electrolyte. The negative electrode of the solid-state battery is a lithium metal negative electrode.

[0131] Performance testing

[0132] (1) Electrochemical performance testing

[0133] The secondary batteries of the above embodiments and comparative examples were subjected to 1 / 3C / 1 / 3C charge-discharge cycle tests under conditions of 45°C and 10MPa restraint force (the voltage test range for charge and discharge was 2.8V-4.25V). The test results are shown in Table 1.

[0134] (2) Gas production test

[0135] The secondary batteries from the above embodiments and comparative examples were suspended using a force gauge and completely immersed in silicone oil heated to 60°C. After the batteries were kept stationary, the force gauge reading was recorded as F1. After storage for 45 days, the force gauge reading was recorded as F2. Combining Newton's theorem and Archimedes' law of buoyancy: F1 - F2 = ρ 液 gV 电芯鼓胀得出 Gas production volume of the battery cell.

[0136] Table 1

[0137]

[0138] As shown in Table 1, comparing Examples 1-8 and Comparative Examples 1-3, it can be seen that the positive electrode active material composition provided in this application improves the energy density of ternary batteries, suppresses gas production, and improves the cycle performance of batteries.

[0139] Comparing Examples 1-8 with Comparative Example 3, it can be seen that the active sites of the lithium-ionized organic material in Comparative Example 3 are too close together, which leads to an increase in steric hindrance within the molecule. The tightly packed active centers also require higher energy input to achieve electrochemical conversion, thus affecting the cycle performance of the battery.

[0140] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0141] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A positive electrode active material composition, characterized in that, include: Ternary materials and lithium-ionized organic materials; The chemical formula of the ternary material is LiNi. x Co y Mn z O2, where 0 <x<1,0<y<1,0<z<1,x+y+z=1; The chemical formula of the lithium-ionized organic material is LiX, wherein X is selected from at least one compound having the structural formulas shown in formulas (I) to (V):

2. The positive electrode active material composition according to claim 1, characterized in that, The mass ratio of the ternary material to the lithium-ionized organic material is (99:1) to (75:25).

3. The positive electrode active material composition according to claim 1 or 2, characterized in that, The LiX is obtained by a lithiation reaction between the X and a lithifying agent.

4. The positive electrode active material composition according to claim 3, characterized in that, The lithiating agent is selected from one or more of LiOH, LiNO3 and Li2CO3.

5. The positive electrode active material composition according to claim 1 or 2, characterized in that, The precursor compound of X is pyrene-4,5,9,10-tetraone.

6. A positive electrode sheet, characterized in that, include: Positive current collector; A positive electrode active material layer is disposed on at least one side of the surface of the positive electrode current collector, wherein the positive electrode active material layer comprises the positive electrode active material composition according to any one of claims 1 to 5.

7. A secondary battery, characterized in that, Includes the positive electrode sheet as described in claim 6.

8. The secondary battery according to claim 7, characterized in that, The secondary battery is a solid-state battery, and the solid-state battery includes a solid electrolyte membrane.

9. The secondary battery according to claim 8, characterized in that, The solid electrolyte membrane includes at least one of oxide solid electrolyte, polymer solid electrolyte, and halide solid electrolyte.

10. An electrical device, characterized in that, Includes the secondary battery as described in any one of claims 7 to 9.

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