Positive active material composition rich in lithium and manganese

Abstract

The present disclosure provides a positive active material composition rich in lithium and manganese. A positive electrode active material for a lithium ion battery may include a compound represented by the general formula LiaMnbNic-xMxO2-yFy, where a is in the range of 1.02 to 1.08, b is in the range of 0.51 to 0.53, c is in the range of 0.40 to 0.47, x is in the range of 0 to 0.1, y is in the range of 0 to 0.1, and M = Co, Cr, or a combination thereof.

Description

Technical Field

[0001] In at least one aspect, a positive electrode active material for lithium-ion batteries is provided. Background Technology

[0002] Compared to currently used nickel-cobalt-manganese (NCM) and nickel-cobalt-aluminum (NCA) materials, lithium- and manganese-rich (LMR) positive electrode active materials are considered promising next-generation cathode materials due to their high gravimetric energy density. Summary of the Invention

[0003] In at least one aspect of this disclosure, a positive electrode active material for a lithium-ion battery is provided. The active material comprises a compound represented by the following general formula 1: a Mn b Ni c-x M x O 2-y F y Where a can be between 1.02 and 1.08, b can be between 0.51 and 0.53, c can be between 0.40 and 0.47, x can be between 0 and 0.1, y can be between 0 and 0.1, and M = Co, Cr, or a combination thereof. The average oxidation state of Mn in the positive electrode active material can be between 3.7 and 4.0. Additionally, the average oxidation state of Ni in the positive electrode active material can be 2.0. When the Li content is 1.04, the Mn content can be 0.52, and the Ni content can follow formula 0.44-x. When the Li content is 1.06, the Mn content can be 0.53, and the Ni content can follow formula 0.40-x. When the Li content is 1.02, the Mn content can be 0.51, and the Ni content can follow formula 0.47-x. The active material can be contained in the cathode.

[0004] In another aspect of this disclosure, a positive electrode for a lithium-ion battery is provided. The electrode comprises a positive electrode active material having a compound represented by the following chemical formula 1: a Mn b Ni c-x M x O 2-y F yWhere a can be between 1.02 and 1.08, b can be between 0.51 and 0.53, c can be between 0.40 and 0.47, x can be between 0 and 0.1, y can be between 0 and 0.1, and M = Co, Cr, or a combination thereof. The average oxidation state of Mn can be between 3.7 and 4.0. The average oxidation state of Ni can be 2.0. When the Li content is 1.04, the Mn content can be 0.52, and the Ni content can follow formula 0.44-x. When the Li content is 1.06, the Mn content can be 0.53, and the Ni content can follow formula 0.40-x. When the Li content is 1.08, the Mn content can be 0.52, and the Ni content can follow formula 0.40-x. When the Li content is 1.02, the Mn content can be 0.51, and the Ni content can follow formula 0.47-x.

[0005] In another aspect of this disclosure, a rechargeable lithium-ion battery having at least one lithium-ion battery cell is proposed. Each lithium-ion battery cell includes a positive electrode having a positive electrode active material as represented by the following formula 1: a Mn b Ni c-x M x O 2-y F y Where a can be between 1.02 and 1.08, b can be between 0.51 and 0.53, c can be between 0.40 and 0.47, x can be between 0 and 0.1, y can be between 0 and 0.1, and M = Co, Cr, or a combination thereof. When the Li content is 1.04, the Mn content can be 0.52, and the Ni content can follow formula 0.44-x. When the Li content is 1.06, the Mn content can be 0.53, and the Ni content can follow formula 0.40-x. When the Li content is 1.08, the Mn content can be 0.52, the Ni content can follow formula 0.40-x, and the average oxidation state of Ni is 2.0. When the Li content is 1.02, the Mn content can be 0.51, and the Ni content can follow formula 0.47-x. Attached Figure Description

[0006] Figure 1A It is a schematic cross-sectional view of a positive electrode containing cathode active material on one side of the current collector;

[0007] Figure 1B It is a schematic cross-sectional view of the positive electrodes containing cathode active material on both sides of the current collector;

[0008] Figure 2 It includes Figure 1A A schematic cross-sectional view of the positive electrode of the battery cell; and

[0009] Figure 3It includes Figure 2 A schematic cross-sectional view of the battery pack containing the battery cells. Detailed Implementation

[0010] The presently preferred compositions, embodiments, and methods of the invention, representing the inventors' most well-known practices, are described. The accompanying drawings are not necessarily drawn to scale. The disclosed embodiments are merely examples, and the invention may be embodied in various alternative forms. Therefore, the specific details provided should not be considered limiting. Rather, they serve as a representative basis for understanding any aspect of the invention and as guidance for those skilled in the art on how to apply the invention in various ways.

[0011] Unless otherwise expressly stated, when a given chemical structure includes substituents on a chemical moiety (e.g., on an aryl, alkyl, etc.), it is assumed that the substituents apply to a more general chemical structure encompassing the given structure. Percentages, “parts,” and ratio values ​​are by weight. The term “polymer” includes “oligomer,” “copolymer,” “terpolymer,” and similar structures. Unless otherwise indicated, the molecular weight provided for any polymer is a weight-average molecular weight. When a group or class of materials is described as suitable or preferred for a given purpose in conjunction with the present invention, it means that a mixture of any two or more members of that group or class is equally suitable or preferred. Descriptions of components in chemical terminology refer to the components as they are added to any specified combination, and chemical interactions between components are not necessarily excluded once mixed. The initial definition of an acronym or abbreviation applies to all subsequent uses of the same abbreviation, and appropriate modifications may be applied to normal grammatical variations of the originally defined abbreviation. Unless otherwise expressly stated, measurements of properties are determined by the same technique referenced before or after the same property.

[0012] Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” as used in the specification and appended claims include a plural of indicators. For example, references to components in the singular are intended to include multiple components. Furthermore, the invention is not limited to the specific embodiments and methods described herein, as specific components and / or conditions may differ. Moreover, the terminology used herein is for the purpose of describing particular embodiments of the invention only and is not intended to be limiting in any way.

[0013] The term "comprising" is synonymous with "including," "having," "containing," or "characterized by." These terms are inclusive and open-ended, meaning they do not exclude additional, undescribed elements or method steps. The phrase "consisting of" means "including" or "composed of," and is generally used to indicate that an object is formed from a specified material.

[0014] The integer range explicitly includes all intermediate integers. For example, the integer range 1 to 10 includes 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. Similarly, the range 1 to 100 includes all integers from 1 to 100. Additionally, when any range is specified, intermediate values ​​that are increments of the difference between the upper and lower limits divided by 10 can be considered as alternative upper or lower limits. For example, if the range is 1.1 to 2.1, the values ​​1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, and 2.0 can be chosen as alternative lower or upper limits.

[0015] Unless otherwise expressly stated, all values ​​and ranges relating to quantities, measurements, percentages, weights, and similar numerical references in this document should be understood as being preceded by the term "about". This applies even if "about" is not explicitly mentioned. The invention lies in the fact that all values ​​and ranges take into account variations that may arise from standard measurement techniques, manufacturing processes, material properties, and the intended functionality of the disclosed aspects. For example, when a composition is described as having "5% by weight of component", it should be understood as "about 5% by weight of component". Additionally, when values ​​are given as ranges such as "100 to 200 units", the range should be interpreted as meaning "about 100 to about 200 units". These variations are implicitly included within the scope of this disclosure.

[0016] The term "positive electrode" refers to the electrode in a lithium-ion battery cell from which current flows during discharge. This electrode is sometimes called the "cathode." Conversely, the term "negative electrode" refers to the electrode in a lithium-ion battery cell from which current flows during discharge. This electrode is sometimes called the "anode."

[0017] The term "cell" or "battery cell" refers to an electrochemical cell comprising at least one positive electrode, at least one negative electrode, an electrolyte, and a separator. The term "battery" or "battery pack" refers to an energy storage device comprising at least one battery cell. In an improved embodiment, a "battery" or "battery pack" is an energy storage device composed of multiple battery cells.

[0018] The term "specific capacity" refers to the capacity of anode active material per unit mass, measured in milliampere-hours per gram (mAh / g).

[0019] As previously mentioned, LMR positive electrode active materials represent a promising class of cathode materials for lithium-ion batteries, characterized by their high specific capacity and energy density. These materials are particularly suitable for applications requiring long distances and high energy, such as electric vehicles and large-scale energy storage systems. A significant feature of LMR materials is their high manganese content, which, due to the relative abundance of manganese, makes them more attractive compared to their cobalt-rich counterparts.

[0020] LMR materials are composites of layered lithium (Li) transition metal oxides with additional Li ions bonded within the lattice. This composite structure can consist of layered LiMO2 and Li2MnO3 components, providing a unique combination of electrochemical properties. Due to the reversible redox reactions of both the transition metal and lattice oxygen, LMR materials exhibit high specific capacities typically exceeding 250 mAh / g. They can operate at high voltages, typically around 4.5 V, contributing to their high energy density. The electrochemical activity of LMR materials involves not only the transition metal redox pair but also the participation of lattice oxygen undergoing reversible redox reactions.

[0021] The high capacity and high voltage of LMR materials result in excellent energy density, making them attractive for applications requiring long-distance and high-energy batteries. The use of manganese (an element more abundant than cobalt) further enhances their appeal. Additionally, manganese-based materials typically offer better thermal stability compared to cobalt-rich materials.

[0022] However, several challenges need to be addressed for the practical application of LMR materials. One problem is voltage decay, i.e., the gradual loss of voltage during cycling, which leads to a decrease in energy density over time. Structural changes during cycling (including transition metal migration and oxygen loss) can affect the long-term cycling stability of LMR materials. Furthermore, LMR materials typically exhibit slower kinetics compared to conventional cathode materials, thus affecting their rate performance. Therefore, there is a need for LMR material compositions for positive electrode active materials in lithium-ion batteries that offer improved rate capability, cell performance, and volumetric energy density. This disclosure provides a composition for an LMR cathode used in lithium-ion batteries.

[0023] In one or more embodiments, the LMR composition has a lower Li content (Li₂MnO₃) than conventional compositions. This modification improves cycle performance, power performance, and rate capability by enhancing the voltage decay and electronic and ionic conductivity of the LMR. However, it is recognized that a lower Li content generally results in a lower capacity than conventional LMR. To offset the potential reduction in capacity, compositions of LMR materials for lithium-ion batteries have been modified to increase the nickel (Ni) content, while adjusting the amount of cobalt (Co) or chromium (Cr) and introducing a small amount of fluorine (F). This adjustment aims to increase the total capacity primarily by leveraging the effect of Ni to control its average oxidation state to 2.0. Meanwhile, the Co content plays a role in increasing both electronic and ionic conductivity, while the addition of F is expected to enhance the structural stability and electrochemical performance of the material.

[0024] On the one hand, it is proposed that Li... a Mn b Ni c-x M x O2-y F y The represented composition, where 1.02 ≤ a ≤ 1.08, 0.51 ≤ b ≤ 0.53, 0.40 ≤ c ≤ 0.47, 0 ≤ x ≤ 0.1, 0 < y ≤ 0.1, and M = Co, Cr, or a combination thereof. This configuration aims to address aspects such as cycle performance, power efficiency, and rate capability. The combination of Co and F with adjusted ratios of Li, Mn, and Ni is intended to enhance the durability and efficiency of the battery. This approach aims to maintain the average oxidation state of Mn between 3.7 and 4.0 and the average oxidation state of Ni at 2.0, thereby contributing to an overall improvement in the electrochemical properties and lifespan of the lithium-ion battery.

[0025] On the other hand, for applications emphasizing higher energy density and improved rate capability, alternative compositions with specific values of a, b, and c are proposed, such as Li 1.08 Mn 0.52 Ni 0.40-x M x O 2-y F y . These versions are designed to support longer charge-discharge cycles under demanding conditions, which is facilitated by the optimized contents of Li, Mn, Ni, Co, and F. The flexibility in adjusting x and y allows for fine-tuning of the electrochemical characteristics of the material, aiming to meet the performance requirements of various applications.

[0026] Reference Figure 1A and Figure 1B , a schematic diagram of the positive electrode 10 containing the positive electrode active material is provided. The positive electrode 10 includes a positive electrode active material layer 12 disposed above and generally in contact with the positive electrode current collector 14. Generally, the positive electrode current collector 14 is a metal plate or metal foil made of a metal such as aluminum (Al), copper (Cu), platinum (Pt), zinc (Zn), titanium (Ti), etc. Currently, Al is most commonly used for the positive electrode current collector. The positive electrode active material is represented by Formula 1:

[0027] Li a Mn b Ni c-x M x O 2-y F y (1)

[0028] where 1.02 ≤ a ≤ 1.08, 0.51 ≤ b ≤ 0.53, 0.40 ≤ c ≤ 0.47, 0 ≤ x ≤ 0.1, 0 < y ≤ 0.1, and M = Co, Cr, or a combination thereof.

[0029] For applications requiring increased power efficiency and robust cycle performance, a specific active electrode composition is Li 1.04 Mn0.52 Ni 0.44-x M x O 2-y F y In this formulation, Co, Cr, F, or combinations thereof are used to tune the electrochemical properties of the material to meet different operational requirements. The average oxidation state of Ni ions is controlled at 2.0 to adjust the capacity contribution from Ni, and the average oxidation state of Mn is maintained between 3.7 and 4.0 to achieve a balance between capacity, stability, and overall performance. The selection of x in the range of 0 to 0.1 and y in the range of 0 to 0.1 allows for fine-tuning of the composition to achieve the desired results.

[0030] In another formulation, for applications requiring higher energy density and increased rate capability, a specific active electrode composition is Li. 1.06 Mn 0.53 Ni 0.41-x M x O 2-y F y This variant is characterized by slightly higher Li and Mn contents to support the battery's ability to exhibit higher capacity under specific conditions. With the inclusion of Co, Cr, F, and combinations thereof to enhance structural stability and electrochemical performance, variables x and y set in the range of 0 to 0.1 allow the composition to be tuned to manage performance according to customized needs. The average oxidation state of Mn is controlled between 3.7 and 4.0, while the average oxidation state of Ni is 2.0, thereby maximizing the electrochemical efficiency and stability of the material. These detailed, specific active electrode compositions can be incorporated into a cathode, which, when combined with the anode and electrolyte, forms a comprehensive lithium-ion battery.

[0031] refer to Figure 2A schematic diagram of a rechargeable lithium-ion battery cell 20 is provided. The rechargeable lithium-ion battery cell 20 includes a positive electrode 10, a negative electrode 22, and a separator 24 inserted between the positive electrode 10 and the negative electrode 22, as described above. The negative electrode 22 includes a negative electrode current collector 26 and a negative electrode active material layer 28, which is disposed above and typically in contact with the negative electrode current collector 26. Typically, the negative electrode current collector 26 is a metal plate or foil made of metals such as Al, Cu, Pt, Zn, and Ti. Currently, Cu is most commonly used for negative electrode current collectors. The rechargeable lithium-ion battery cell 20 is immersed in an electrolyte 30 enclosed by a battery cell housing 32. The electrolyte 30 is absorbed into the separator 24. In other words, the separator 24 includes the electrolyte 30, thereby allowing Li ions to move between the positive electrode 10 and the negative electrode 22. The electrolyte 30 includes a non-aqueous organic solvent and a Li salt. Non-aqueous organic solvents are used as a medium for transporting ions that participate in the electrochemical reactions of the rechargeable lithium-ion battery cell 20. Advantageously, the rechargeable lithium-ion battery cell 20 can have a specific capacity greater than 250 mAh / g.

[0032] refer to Figure 3 A schematic diagram of a rechargeable lithium-ion battery 40 is provided. Battery 40 includes... Figure 2 At least one lithium-ion battery cell 20 i 20 lithium-ion battery cells i Each of the components includes: a positive electrode 10 comprising a compound represented by Formula 1; a negative electrode 22 comprising a negative electrode active material; and an electrolyte 30, wherein i is a lithium-ion battery cell 20. i Each of these is an integer marker. The marker i ranges from 1 to nmax, where nmax is the total number of battery cells in the rechargeable lithium-ion battery 40. The electrolyte 30 comprises a non-aqueous organic solvent and a Li salt. The non-aqueous organic solvent serves as a medium for transporting ions participating in the electrochemical reactions of the battery 40. Battery cell 20 i It can be connected in series, parallel, or in combination thereof. The cross terminals 42 and 44 provide voltage output from battery 40.

[0033] refer to Figure 2 and Figure 3 The separator 24 physically separates the negative electrode 22 from the positive electrode 10, thereby preventing short circuits while allowing Li ion transport for charging and discharging. Therefore, the separator 24 can be made of any material suitable for this purpose. Examples of suitable materials for constituting the separator 24 include, but are not limited to, polytetrafluoroethylene (PTFE). Separators 24 can be made of woven or nonwoven fabrics. For example, polyolefin-based polymer separators (such as polyethylene and / or polypropylene) are commonly used in lithium-ion batteries. To ensure heat resistance or mechanical strength, coated separators, including coatings of ceramic or polymeric materials, can be used.

[0034] Electrolyte 30 comprises a Li salt dissolved in the non-aqueous organic solvent mentioned above. Therefore, electrolyte 30 comprises Li ions that can be intercalated into the positive electrode active material during discharge and into the anodic active material during charging. Examples of Li salts include, but are not limited to, LiPF6, LiBF4, LiSbF6, LiAsF6, LiC4F9SO3, LiClO4, LiAlO2, LiAlCl4, LiCl, LiI, LiB(C2O4)2, and combinations thereof. In an improved embodiment, electrolyte 30 comprises a Li salt in an amount from about 0.1 M to about 2.0 M.

[0035] Non-aqueous organic solvents serve as mediators for transporting ions, particularly Li ions involved in electrochemical reactions within the battery. Suitable non-aqueous organic solvents encompass carbonate-based solvents, ester-based solvents, ether-based solvents, ketone-based solvents, alcohol-based solvents, aprotic solvents, and combinations thereof. Examples of carbonate-based solvents include, but are not limited to, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, methyl ethyl carbonate, ethylene carbonate, propylene carbonate, butyl carbonate, and combinations thereof. Ester-based solvents include, but are not limited to, methyl acetate, ethyl acetate, n-propyl acetate, methyl propionate, ethyl propionate, γ-butyrolactone, decanolactone, valproic acid lactone, caprolactone, and combinations thereof. Ether-based solvents include, but are not limited to, dibutyl ether, tetraethylene glycol dimethyl ether, diethylene glycol dimethyl ether, dimethoxyethane, 2-methyltetrahydrofuran, and tetrahydrofuran. Ketone-based solvents may include cyclohexanone. Alcohol-based solvents include, but are not limited to, methanol, ethanol, n-propanol, and isopropanol. Aprotic solvents include, but are not limited to, nitriles such as R-CN (where R is C). 2-20 Straight-chain, branched, or cyclic hydrocarbons, which may include double bonds, aromatic rings, or ether bonds, amides such as dimethylformamide, dioxolane such as 1,3-dioxolane, and sulfolane.

[0036] Non-aqueous organic solvents can be used alone or as mixtures, and are typically formulated to optimize battery performance. In one improved approach, carbonate-based solvents are prepared by mixing cyclic carbonates with linear carbonates. Additionally, the electrolyte may include vinylene carbonate-based or ethylene carbonate-based compounds to extend battery cycle life.

[0037] The negative and positive electrodes can be fabricated using methods known to those skilled in the art of lithium-ion batteries. Typically, active materials (positive or negative electrodes) are mixed with conductive materials and binders in a solvent (such as N-methylpyrrolidone). This mixture forms an active material composition, which is then coated onto a current collector. Because the electrode fabrication methods are well-established, they are not described in detail in this specification. While N-methylpyrrolidone is a commonly used solvent, other solvents may also be suitable for this process.

[0038] The positive electrode active material layer 12 comprises a positive electrode active material represented by Formula 1, a binder, and a conductive material. The binder enhances the adhesion between the positive electrode active material particles and the positive electrode current collector 14. Suitable binders include, but are not limited to, 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, acrylate styrene-butadiene rubber, epoxy resin, nylon, and combinations thereof.

[0039] A conductive material provides conductivity to the positive electrode 10. Suitable conductive materials include, but are not limited to, natural graphite, artificial graphite, carbon (C) black, acetylene black, Ketjen black, C fibers, Cu, metal powders, and metal fibers. Examples of metal powders and metal fibers include those composed of Ni, Al, silver (Ag), and combinations thereof.

[0040] Refer to Figure 1. Figure 2 and Figure 3 The negative electrode active material layer 28 comprises a negative electrode active material, a binder, and optionally a conductive material. The negative electrode active material used herein may be any negative electrode material known to those skilled in the art of lithium-ion batteries. Negative electrode active materials include, but are not limited to, C-based negative electrode active materials, silicon-based (Si-based) negative electrode active materials, and combinations thereof. Suitable C-based negative electrode active materials may include graphite and graphene. Suitable Si-based negative electrode active materials may include at least one selected from Si, Si oxide, Si oxide coated with conductive C on its surface, and Si coated with conductive C on its surface. For example, Si oxide may be of the formula SiO z Description, where z is 0.09 to 1.1. A mixture of C-based or Si-based anode active materials can also be used as anode active materials.

[0041] The negative electrode active material layer 28 comprises a negative electrode active material, a binder, and optionally a conductive material. Suitable negative electrode active materials for use in this context are well known to those skilled in the art of lithium-ion batteries. These materials include, but are not limited to, C-based negative electrode active materials, Si-based negative electrode active materials, and combinations thereof.

[0042] The negative electrode binder enhances the adhesion of the negative electrode active material particles to each other and to the current collector. The binder can be a non-aqueous binder, an aqueous binder, or a combination of both. Non-aqueous binders include polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, polymers containing ethylene oxide, polyvinylpyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyamideimide, polyimide, and combinations thereof. The aqueous binder can be a rubber-based binder or a polymer resin-based binder. Examples of rubber-based binders include styrene-butadiene rubber, acrylated styrene-butadiene rubber, acrylonitrile-butadiene rubber, acrylic rubber, butyl rubber, fluororubber, and combinations thereof. Polymer resin binders include polyethylene, polypropylene, ethylene-propylene copolymer, poly(ethylene oxide), polyvinylpyrrolidone, epichlorohydrin, polyphosphazene, polyacrylonitrile, polystyrene, ethylene-propylene-diene copolymer, polyvinylpyridine, chlorosulfonated polyethylene, latex, polyester resin, acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, and combinations thereof.

[0043] Although the exemplary embodiments are described above, they are not intended to represent all possible forms of the invention. The language used in the specification is descriptive rather than restrictive, and it should be understood that various modifications can be made without departing from the spirit and scope of the invention. Additionally, the features of different embodiments can be combined to create further embodiments of the invention.

[0044] According to the present invention, there is provided a positive electrode active material for a lithium ion battery, the positive electrode active material having a compound represented by the following general formula 1: Li a Mn b Ni c-x M x O 2-y F y (1), where 1.02 ≤ a ≤ 1.08; 0.51 ≤ b ≤ 0.53; 0.40 ≤ c ≤ 0.47; 0 ≤ x ≤ 0.1; 0 < y ≤ 0.1; and M = Co, Cr, or a combination thereof.

[0045] According to an embodiment, the average oxidation state of Mn is between 3.7 and 4.0.

[0046] According to an embodiment, the average oxidation state of Ni is 2.0.

[0047] According to an embodiment, a is 1.04, b is 0.52, and c is 0.44.

[0048] According to an embodiment, a is 1.06, b is 0.53, and c is 0.41.

[0049] According to an embodiment, a is at 1.08, b is 0.52, and c is 0.40.

[0050] According to an embodiment, a is 1.02, b is 0.51, and c is 0.47.

[0051] According to an embodiment, the positive electrode active material is included in the cathode.

[0052] According to the present invention, there is provided a positive electrode for a lithium ion battery, the positive electrode having a positive electrode active material including a compound represented by the following Chemical Formula 1: Li a Mn b Ni c-x M x O 2-y F y (1), where: 1.02 ≤ a ≤ 1.08; 0.51 ≤ b ≤ 0.53; 0.40 ≤ c ≤ 0.47; 0 ≤ x ≤ 0.1; 0 < y ≤ 0.1; and M = Co, Cr, or a combination thereof.

[0053] According to an embodiment, the average oxidation state of Mn is between 3.7 and 4.0.

[0054] According to an embodiment, the average oxidation state of Ni is 2.0.

[0055] According to an embodiment, a is 1.04, b is 0.52, and c is 0.44.

[0056] According to an embodiment, a is 1.06, b is 0.53, and c is 0.41.

[0057] According to an embodiment, a is 1.08, b is 0.52, c is 0.40, and the average oxidation state of Ni ions is 2.0.

[0058] According to an embodiment, a is 1.02, b is 0.51, and c is 0.47. <e

[0059] According to the present invention, there is provided a rechargeable lithium ion battery having at least one lithium ion battery cell, each lithium ion battery cell including: a positive electrode including a positive electrode active material represented by the following Formula 1: Li<00s00067>[[ID=u1]]Mn b Ni c-x M x O 2-y F y (1), where: 1.02 ≤ a ≤ 1.08; 0.51 ≤ b ≤ 0.53; 0.40 ≤ c ≤ 0.47; 0 ≤ x ≤ e0.1; 0 < y ≤ 0.1; M = Co, Cr, or a combination thereof; a negative electrode including a negative electrode active material; and an electrolyte.

[0060] It should be noted that there seems to be an error in the original text where "0 ≤ x ≤ e0.1" in the translation of item might be incorrect. It should probably be "0 ≤ x ≤ 0.1" as in the previous similar expressions. If this is a real error, please correct it in the original text for a more accurate translation.According to the embodiment, a is 1.04, b is 0.52, and c is 0.44.

[0061] According to the embodiment, a is 1.06, b is 0.53, and c is 0.41.

[0062] According to the example, a is 1.08, b is 0.52, c is 0.40, and the average oxidation state of Ni is 2.0.

[0063] According to the embodiment, a is 1.02, b is 0.51, and c is 0.47.

Claims

1. A positive electrode active material for lithium-ion batteries, said positive electrode active material comprising a compound represented by the following general formula 1: Li a Mr b Ni c-x Co x O 2-y F y (1) in: 1.02≤a≤1.08， 0.51≤b≤0.53， 0.40≤c≤0.47， 0 ≤ x ≤ 0.1, and 0<y≤0.1。 2. The positive electrode active material according to claim 1, wherein the average oxidation state of Mn is between 3.8 and 4.

0.

3. The positive electrode active material according to claim 1, wherein the average oxidation state of Ni is 2.

0.

4. The positive electrode active material as described in claim 1, wherein a is 1.04, b is 0.52, and c is 0.

44.

5. The positive electrode active material as described in claim 1, wherein a is 1.06, b is 0.53, and c is 0.

41.

6. The positive electrode active material as described in claim 1, wherein a is 1.08, b is 0.52, and c is 0.

40.

7. The positive electrode active material as claimed in claim 1, wherein a is 1.02, b is 0.51, and c is 0.

47.

8. The positive electrode active material as claimed in claim 1, wherein the positive electrode active material is contained in the cathode.

9. A positive electrode for a lithium-ion battery, the positive electrode comprising a positive electrode active material, the positive electrode active material comprising a compound represented by the following chemical formula 1: Li a Mr b Ni c-x Co x O 2-y F y (1) in: 1.02≤a≤1.08， 0.51≤b≤0.53， 0.40≤c≤0.47， 0 ≤ x ≤ 0.1, and 0<y≤0.1。 10. The positive electrode of claim 9, wherein the average oxidation state of Mn is between 3.7 and 4.

0.

11. The positive electrode of claim 9, wherein the average oxidation state of Ni is 2.

0.

12. The positive electrode as claimed in claim 9, wherein a is 1.04, b is 0.52, and c is 0.

44.

13. The positive electrode as claimed in claim 9, wherein a is 1.06, b is 0.53, and c is 0.

41.

14. The positive electrode as claimed in claim 9, wherein a is 1.08, b is 0.52, c is 0.40, and the average oxidation state of Ni ions is 2.

0.

15. The positive electrode as claimed in claim 9, wherein a is 1.02, b is 0.51, and c is 0.47.

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