Process for manufacturing lithium-containing mixed metal oxide materials

Abstract

A cathode material is formed by calcining a mixed metal oxide composition. The mixed metal oxide composition is formed by mixing (i) a metal-containing precursor with (ii) a lithium precursor containing lithium peroxide (Li2O2), lithium hydroperoxide (LiOOH), lithium peroxide monoperoxohydrate trihydrate (Li2O2.H2O2.3H2O), or a mixture of two or more of the above. The resulting cathode material has the formula (II): qLi2MnO3·(1-q)LiNi a Mn b Co c M y O 2+z The compound contains (II), where 0≦q≦0.8, c=1-ab, 0≦a≦1, 0

Description

[Technical Field]

[0001] Cross-reference of related applications This application claims the interests of U.S. Provisional Patent Application No. 63 / 469,998, filed on 31 May 2023, which is incorporated herein by reference in its entirety.

[0002] This disclosure relates to a process for producing lithium-containing mixed metal oxides, including oxides useful for manufacturing cathodes for secondary lithium-ion batteries. [Overview of the Initiative]

[0003] Lithium-containing mixed metal oxides are widely used as cathode materials for producing cathodes useful in secondary Li-ion batteries. Previously, these cathode materials involved combining a lithium-containing precursor with a mixed transition metal-containing precursor (e.g., nickel-manganese-cobalt oxide) to form a mixture, and then using this mixture for cathode formation. 3+ These have been formed by placing the material under conditions that lead to the formation of lithium mixed metal oxides (e.g., lithium nickel manganese cobalt oxide, often abbreviated as "NMC"). Common lithium precursors used for these purposes are lithium hydroxide or lithium carbonate, and their formation is typically carried out under a flow of oxygen to control the chemical reaction environment. As an example, NMC 811 (LiNi 0.8 Mn 0.1 Co 0.1 High-performance cathode materials such as qLi2MnO3·(1-q)LiMO2 can be synthesized in an oxygen-rich atmosphere using lithium hydroxide (LiOH or LiOH.H2O) as the lithium source, with the addition of a process to remove by-products such as water or carbon dioxide, depending on the selected lithium source. Another example is the lithium, manganese-rich cathode material qLi2MnO3·(1-q)LiMO2, e.g., 0.5(Li2MnO3)·0.5(LiNi 0.5 Mn 0.5 O2)(If normalized to O2, Li 1.2Ni 0.2 Mn 0.6 (which may also be represented as O2) can be similarly synthesized in an oxygen-rich atmosphere using lithium hydroxide (LiOH or LiOH·H2O) as the lithium source, and depending on the selected lithium source, a process for removing by-products such as water or carbon dioxide is added. However, in these processes, it is necessary to supply a rich oxygen stream to carry out the process, and thus it is costly and may be more complex to carry out on a commercial scale. Therefore, there is a continuing need to develop new processes for manufacturing lithium-containing cathode materials more efficiently and economically.

[0004] Generally, the present disclosure provides a calcined mixed metal oxide composition for forming a cathode material, the composition comprising a compound having the formula (II), qLi2MnO3·(1 - q)LiNi a Mn b Co c M y O 2+z (II) where 0 ≤ q ≤ 0.8, c = 1 - ab, 0 ≤ a ≤ 1, 0 < b ≤ 1, 0 ≤ y ≤ 0.05, -0.025 ≤ z ≤ 0.125, and M is selected from the group consisting of Al, Mg, Ti, Mo, Nb, Zr, Hf, Ta, W, B, P, F, and combinations of any two or more of the foregoing.

[0005] Generally, the present disclosure also provides a process comprising calcining a mixed metal oxide composition to form a cathode material, where the mixed metal oxide compound is formed by mixing (i) a transition metal-containing precursor and (ii) a lithium precursor comprising lithium peroxide (Li2O2), lithium hydroperoxide (LiOOH), lithium peroxide monoperoxohydrate trihydrate (Li2O2·H2O2·3H2O), or a mixture of any two or more of the foregoing, and the me tal-containing precursor comprises a compound or mixture of compounds each having the formula (I), or an oxide counterpart thereof, qMn(OH)2·(1-q)Ni a Mn b Co c M y X 1+k (I) Where 0 ≦ q ≦ 0.8, c = 1 - a - b, 0 ≦ a ≦ 1, 0 < b ≦ 1, 0 ≦ y ≦ 0.05, M contains one or more selected from the group consisting of Al, Mg, Ti, Mo, Nb, Zr, Hf, Ta, W, B, P, and F, and X is OH - , CO3 2- , NO3 - , SO4 2- , C2O4 2- , C2H3O2 - , CHO2 - , selected from the group consisting of stearate, oleate, tartrate, and lactate, when X is OH - , C3H3O2 - , NO3 - , CHO2 - , selected from the group consisting of stearate, oleate, and lactate, -0.025 ≦ k ≦ 0.25, when X is other than these, 0.975 ≦ k ≦ 1.25 The cathode material thus formed contains a compound having the formula (II) qLi2MnO3·(1-q)LiNi a Mn b Co c M y O 2+z (II) Where 0 ≦ q ≦ 0.8, c = 1 - ab, 0 ≦ a ≦ 1, 0 < b ≦ 1, 0 ≦ y ≦ 0.05, -0.025 ≦ z ≦ 0.125, and M is selected from the group consisting of Al, Mg, Ti, Mo, Nb, Zr, Hf, Ta, W, B, P, F, and any combination of two or more of the foregoing

[0006] Interestingly, oxygen (O2) generated in situ during the synthesis of cathode materials from lithium precursors has been found to accelerate the reaction, while water, a typical by-product generated during the synthesis of cathode materials from LiOH·H2O or LiOH, needs to be removed from the system as quickly as possible. This characteristic reduces the need for oxygen supply to the reactor, overcomes the diffusion limit of oxygen in the precursor mixture during the reaction, and consequently, when using lithium precursors (as defined herein), a much simpler reactor configuration can be used, shortening the synthesis time of the cathode material. Furthermore, in at least some aspects of this disclosure, lithium precursors enable the synthesis of single-crystal NMC materials with, for example, preferred particle size and performance. For example, NMC 811 prepared according to this disclosure has improved particle size and performance compared to single-crystal NMC 811 synthesized using the same process with LiOH·H2O or LiOH as the lithium source. Using lithium precursors of this disclosure also enables the synthesis of cathode materials at higher temperatures compared to when using LiOH·H2O or LiOH. Because Li2O has a higher melting point compared to LiOH or Li2CO3, in some aspects of the present invention, using the lithium precursor of the present disclosure instead of LiOH·H2O or LiOH may result in faster reactions at high temperatures and shorter conversion times. In at least some aspects of the present disclosure, the process also facilitates the production of cathode materials using continuous reactors such as rotary kilns while reducing or eliminating the use of oxygen supply to the reactor. This cathode material should also be suitable for incorporation into core-shell and gradient-type cathode materials, or for use as core-shell and gradient-type cathode materials.

[0007] Accordingly, in one embodiment, the process of the present disclosure is carried out in the mixing step such that the moles of Li are equal to or greater than the total moles of Ni, Mn, and Co. In another embodiment, the mixing step is carried out in an atmosphere containing less than 3% by weight of moisture in order to form a mixed metal oxide composition. In yet another embodiment, the mixing step is carried out under ambient temperature and pressure conditions.

[0008] In another aspect of the disclosure, the calcination process is carried out by an external supply of a gas containing oxygen in an amount ranging from about 0.1% to about 90% by weight. In yet another aspect of the disclosure, the external supply of gas provides an amount of oxygen such that the molar ratio of oxygen to the mixed metal oxide composition to be calcined is 1:4 or less. In yet another aspect, the calcination process is carried out in an atmosphere with a moisture content of 3% by weight or less. In yet another aspect, the calcination process is carried out at a temperature ranging from 700°C to 1200°C for a period of time ranging from 1 hour to 24 hours.

[0009] In at least some aspects of this disclosure, the process may further include pre-oxidizing a metal-containing precursor before the mixing step.

[0010] In another aspect of this disclosure, the mixed metal oxide composition in the process is in the form of fine particles with an average particle size of less than 100 microns.

[0011] In yet another embodiment, in the process, the cathode material is in the form of fine particles with an average particle size of less than 50 microns.

[0012] In yet another aspect of this disclosure, the mixed metal oxide composition in the process is continuously supplied to the reactor, and the cathode material is continuously removed from the reactor, at least partially. In another aspect, the reactor includes either a rotary reactor or a roller hearth kiln.

[0013] While several aspects and embodiments of this disclosure are disclosed herein, further embodiments will become apparent to those skilled in the art from the following detailed description. As will be apparent, certain embodiments disclosed herein can be modified in various ways that will be apparent to those skilled in the art in light of this disclosure, without departing in any way from the spirit and scope of the claims presented below. Accordingly, the drawings and detailed description should be considered as illustrative and not restrictive in nature.

[0014] For a detailed description of specific embodiments of the disclosed subject matter, please refer here to the attached drawings. [Brief explanation of the drawing]

[0015] [Figure 1-1a] This is an overall scanning electron microscope (SEM) image of the final NMC 811 synthesized in a stream of O2 using Li2O as the lithium source in Comparative Example 1. [Figure 1-1b] This is a magnified SEM image of the final NMC 811 synthesized in a stream of O2 using Li2O as the lithium source in Comparative Example 1. [Figure 1-2] This is an X-ray powder diffraction (XRD) characterization evaluation of the final product of Comparative Example 1. [Figure 2-1] This is a cross-sectional SEM image of NMC 811 synthesized using LiOH·H2O in an O2 stream in Comparative Example 2. [Figure 2-2] This is the XRD characterization of the final product of Comparative Example 2. [Figure 3-1a] This is an overall SEM image of NMC 811 synthesized using Li2O2 in an O2 stream in Example 1. [Figure 3-1b] This is a magnified SEM image of NMC 811 synthesized using Li2O2 in an O2 stream in Example 1. [Figure 3-2] This is an XRD characterization evaluation of the final product of Example 1. [Figure 4-1a] This is an overall SEM image of NMC 811 synthesized using Li2O2 in an argon stream in Example 2. [Figure 4-1b] This is a magnified SEM image of NMC 811 synthesized using Li2O2 in an argon stream in Example 2. [Figure 4-2] This is the XRD characterization of the final product of Example 2. [Figure 5] This is the XRD characterization of the final product of Example 3. [Figure 6] This is the XRD analysis pattern of the product formed in Example 4.1. [Figure 7-1] This is the XRD analysis pattern of the product formed in Example 4.2. [Figure 8-1] This is the XRD analysis pattern of the product formed in Example 4.3. [Figure 9-1] This is the XRD analysis pattern of the product formed in Example 4.4. [Figure 10-1] This is the XRD analysis pattern of the product formed in Example 4.5. [Figure 7-2] The original cross-sectional SEM image (left) and the binary cross-sectional SEM image from thresholding of the product in Example 4.2 are shown. [Figure 8-2] The original cross-sectional SEM image (left) and the binary cross-sectional SEM image from thresholding of the product in Example 4.3 are shown. [Figure 9-2] The original cross-sectional SEM image (left) and the binary cross-sectional SEM image from thresholding of the product in Example 4.4 are shown. [Figure 10-2] The original cross-sectional SEM image (left) and the binary cross-sectional SEM image from thresholding of the product in Example 4.5 are shown. [Figure 11] These are the charge and discharge curves of the product from Example 4.1. [Figure 12] These are the charge and discharge curves of the product from Example 4.2. [Figure 13] These are the charge and discharge curves of the product from Example 4.3. [Figure 14] These are the charge and discharge curves of the product from Example 4.4. [Figure 15] These are the charge and discharge curves of the product from Example 4.5. [Figure 16] This bar graph compares the initial cycle capacity and Coulomb efficiency (CE) during charging and discharging of batteries prepared using the products of Examples 4.1 to 4.5 with those when LiOH·H2O or LiOH was used as the lithium precursor. [Figure 17] This bar graph compares the aspect ratio of primary particles of NMC 811 synthesized from Examples 4.2 to 4.5 with that of the case where LiOH·H2O was used as the lithium precursor. [Modes for carrying out the invention]

[0016] While the claimed subject matter may take on various modifications and alternative forms, the drawings(s) illustrate specific features or characteristics of the embodiments described herein in detail as examples. However, it should be understood that the description of specific embodiments herein is not intended to limit the claimed subject matter to the specific forms disclosed, but rather to encompass all modifications, equivalents, and alternatives that fall within the spirit and scope defined by the appended claims.

[0017] definition To more clearly define the terms used in this disclosure, the following definitions are provided. Unless otherwise indicated, the following definitions apply to this disclosure. Terms not set forth below have their usual customary meanings as understood by a person skilled in the art related to this disclosure in the context of this disclosure. To the extent that any definition or usage provided by any document incorporated herein by reference conflicts with any definition or usage provided herein, the definition or usage provided herein shall prevail.

[0018] In this disclosure, the subject matter features are described in such a way that different combinations of features may be envisioned within a particular embodiment. With respect to all embodiments and features disclosed herein, all combinations that do not adversely affect the designs, systems, compositions, processes, or methods described herein are intended, whether or not a particular combination is explicitly described. Furthermore, unless expressly stated otherwise, any combination of embodiments or features disclosed herein may be used to describe designs, systems, compositions, processes, or methods of the present invention that are consistent with this disclosure.

[0019] In this disclosure, compositions and / or processes or methods are often described in terms of "comprising" various components or steps, but unless otherwise specified, compositions and methods may also "consist essentially of" or "consist of" various components or steps. For example, a process consistent with an aspect of the disclosed subject matter may include, or essentially consist of, or be composed of the process steps shown.

[0020] Unless otherwise specified, the terms "a," "an," and "the" are intended to include multiple choices, e.g., at least one, one or more, and one or more.

[0021] The term "average particle size" is intended to mean the average diameter of particles in the reference composition, as measured by laser diffraction particle size distribution measurement.

[0022] In this specification, the terms “room temperature” or “ambient temperature” are used to refer to any temperature between 15°C and 35°C in which no external heat or cooling source is directly applied to the reaction vessel. Therefore, the terms “room temperature” and “ambient temperature” encompass individual temperatures between 15°C and 35°C in which no external heat or cooling source is directly applied to the reaction vessel, as well as any temperature range, subrange, and combination of subranges. In this specification, the term “atmospheric pressure” is used to refer to the air pressure on Earth in which no external pressure regulation means are used. Generally, unless at extreme altitudes on Earth, “atmospheric pressure” is approximately 1 atmosphere (or approximately 14.7 psi or approximately 101 kPa).

[0023] The term “approximately” means that quantities, sizes, formulations, parameters, and other quantities and characteristics may be approximate, including, where necessary, greater or less, to reflect tolerances, conversion factors, rounding, measurement errors, and other factors known to those skilled in the art. Generally, quantities, sizes, formulations, parameters, or other quantities or characteristics are “approximately” or “about,” whether explicitly stated as such. The term “approximately” also encompasses quantities that differ depending on the different equilibrium conditions of compositions obtained from a particular initial mixture. Whether modified by the term “approximately,” the claims include equivalent quantities to those stated.

[0024] Where any kind of numerical range is disclosed or claimed in this specification (e.g., "ranging from...", "in a range of from...", "in the range of from...", "in a range of from", "in a range of"), unless otherwise specified, the intent is to individually disclose or claim each possible numerical value or ratio that the range can reasonably encompass, including the endpoints of the range and any subranges and combinations of subranges contained therein.

[0025] Embodiments disclosed herein can provide material that is suitable for satisfying certain features of embodiments separated by the term “or”. For example, certain features of disclosed subject matter may be disclosed as follows: Feature X may be A, B, or C. Also, for each feature, its description may also be expressed as a list of alternatives, and therefore the statement “Feature X is A, or alternatively B, or alternatively C” is also an embodiment of the disclosure, whether or not this statement is explicitly stated.

[0026] Any methods and materials similar to or equivalent to those described herein may be used in carrying out or testing the subject matter described herein, but this specification describes typical methods and materials.

[0027] All publications and patents referenced herein are incorporated herein by reference for the purpose of describing and disclosing, for example, the structures and methodologies described in publications that can be used in connection with the subject matter described herein.

[0028] Hereinafter, exemplary embodiments of the claimed subject matter are disclosed. For clarity, not all features of actual embodiments are described herein. It will be understood that in the development of any such actual embodiment, a number of embodiment-specific decisions must be made to achieve the specific goals of the developer, which vary by embodiment, such as compliance with system-related and business-related constraints. Furthermore, it will be understood that such development efforts, though complex and time-consuming, are routine tasks for those skilled in the art who benefit from this disclosure.

[0029] A. Mixed metal oxide composition and its formation As described above, the mixed metal oxide compositions used in the processes of this disclosure are formed by mixing a metal-containing precursor with a lithium precursor. As used herein, “lithium precursor” means a precursor comprising lithium peroxide (Li2O2), lithium hydroperoxide (LiOOH), lithium peroxide monoperoxohydrate trihydrate (Li2O2.H2O2.3H2O), or a mixture of two or more of the above. In addition to one or more of the above, the lithium precursor may also include other lithium salts, such as lithium hydroxide or lithium hydroxide monohydrate or lithium carbonate. The metal-containing precursor mixed with the lithium precursor comprises a compound or mixture of compounds having formula (I), or an oxide equivalent thereof. qMn(OH)2·(1-q)Ni a Mn b Co cM y X 1+k (I) where 0 ≦ q ≦ 0.8, c = 1 - a - b, 0 ≦ a ≦ 1, 0 < b ≦ 1, 0 ≦ y ≦ 0.05, M contains one or more selected from the group consisting of Al, Mg, Ti, Mo, Nb, Zr, Hf, Ta, W, B, P and F, and X is OH - , CO3 2- , NO3 - , SO4 2- , C2O4 2- , C2H3O2 - , CHO2 - , selected from the group consisting of stearate, oleate, tartrate and lactate, and when X is OH - , C2H3O2 - , NO3 - , CHO2 - , selected from the group consisting of stearate, oleate and lactate, -0.025 ≦ k ≦ 0.25, and when X is other than these, 0.975 ≦ k ≦ 1.25.

[0030] Non-limiting examples of suitable metal-containing precursors include Ni 0.82 Mn 0.06 Co 0.12 (OH)2, Ni 0.88 Co 0.06 Mn 0.03 Al<{ 0.03 (OH)2 and the like. Non-limiting examples of suitable oxide counterparts of the metal-containing precursors include Ni 0.82 Mn 0.06 Co 0.12 O, Ni 0.88 Co 0.06 Mn 0.03 Al 0.03 O and the like.

[0031] The ratio of the metal-containing precursor to the lithium precursor may vary, but in at least one aspect of this disclosure, the moles of Li are equal to or greater than the total moles of Ni, Mn, and Co in the mixture. The mixing process is carried out in an atmosphere in which the moisture level is minimized, preferably less than 3% by weight. The mixing process can be carried out at various temperatures and pressures, but is preferably carried out under or within typical Earth temperature and pressure conditions.

[0032] In at least some embodiments, the process may further include dehydrating the metal-containing precursor before the mixing step to further minimize the presence of moisture. In at least some embodiments of the present disclosure, the mixed metal oxide composition thus formed is in the form of fine particles with an average particle size of less than 100 microns or less than 50 microns.

[0033] B. Calcination of mixed metal oxide compositions The caking step in the process carried out in accordance with this disclosure can be performed at various temperatures and times, and in various atmospheres, consistent with the teachings described herein. For example, caking The process can be carried out at a peak or baking temperature in the range of approximately 500°C to 1200°C, or approximately 700°C to 1100°C, or approximately 750°C to 1000°C. In these and other embodiments, these temperature ranges are intended to also include situations in which the baking process is carried out not at a single fixed temperature, but at a series of different temperatures within each range (e.g., an initial baking temperature, a peak baking temperature, and / or a temperature gradient between the initial and peak baking temperatures that changes over time). For example, the baking process can start at an initial baking temperature, and then the baking temperature can be increased to the peak baking temperature.

[0034] The duration of the calcination process is not necessarily limited to a specific period in any aspect of this disclosure. The appropriate calcination time may vary depending on several variables, such as the initial / peak calcination temperature and the atmosphere in which the calcination takes place. However, generally, the calcination process can be carried out for a period that may range from about 1 hour to about 24 hours.

[0035] In the calcination process, an external supply of gas is typically provided, which is inert, contains oxygen in amounts ranging from about 0.1% to about 90% by weight, or is a pure inert gas flowing at a rate below the optimal speed. Alternatively, the external supply of gas provides an amount of oxygen such that the molar ratio of oxygen supplied from the external supply of gas to the mixed metal oxide composition being calcined is 1:4 or less.

[0036] In yet another embodiment, the calcination process is carried out in an atmosphere with a moisture content of 3% by weight or less.

[0037] As can be understood herein, the mixed metal oxide composition used in at least some aspects of the process can be continuously supplied to a reactor carrying out the calcination step, and the resulting cathode material product can be continuously or semi-continuously formed by at least partially continuously removing it from the reactor. A variety of suitable calcination reactors can be used, but in at least some aspects of this disclosure, the calcination reactor used, such as a rotary reactor or a roller hearth kiln, facilitates continuous or semi-continuous operation. [Examples]

[0038] While the subject matter has been described in general terms, the following examples are provided to illustrate specific embodiments of the subject matter of this disclosure, for the purpose of demonstrating their implementation and merits. It should be understood that these examples are provided for illustrative purposes only and are not intended to limit the scope of the claims in any way.

[0039] Comparative Example 1 LiNi using Li2O in an oxygen atmosphere 0.82 Mn 0.06 Co0.12 Solid-phase synthesis and characterization of O2 (NMC 811) synthesis Hydroxide precursor Ni 0.82 Mn 0.06 Co 0.12 Twenty grams of (OH)2 (CNGR Advanced Material Co., China) were calcined in an oxygen atmosphere at 900°C for 15 hours to convert it into an oxide precursor, and all moisture generated by the environment was removed. Next, in an argon-filled glove box, 5 grams of the oxide precursor were mixed and ground for 10 minutes using a mortar and pestle with 1.305 grams of Li2O (Albemarle Corporation) at a Li-to-TM molar ratio of 1.30. The mixture was heated in a tubular furnace at 900°C under a constant oxygen flow (0.2 NI / min) at a heating and cooling rate of 10°C / min for 10 hours.

[0040] Characteristic evaluation As shown in Figures 1-1a and 1-1b, the formed NMC 811 (LiNi 0.82 Mn 0.06 Co 0.12 The scanning electron microscope (SEM) image of O2 shows aggregates with a primary particle size of approximately 1-2 μm. The X-ray powder temperature of NMC 811 shown in Figure 1-2 XRD (X-ray dimorphism) confirms the formation of a layered structure.

[0041] Comparative Example 2 LiNi 0.82 Mn 0.06 Co 0.12 Solid-phase synthesis and characterization of O2 (NMC 811) synthesis The compound is a transition metal-containing precursor Ni 0.82 Mn 0.06 Co 0.12 Synthesized from (OH)2 and LiOH. 0.82 Mn 0.06 Co 0.12210 grams of (OH)₂ and 4.76 grams of LiOH were introduced into a plastic container at a Li to TM molar ratio of 1.05, and acoustic mixing was performed for 1 minute each while gradually increasing the force to 50 times, 60 times, and 70 times the gravity. After mixing, the mixture was transferred to an alumina crucible and placed in a tubular furnace under an oxygen flow. Ni 0.82 Mn 0.06 Co 0.12 The mixture of (OH)₂ and LiOH was heat-treated at 500 °C for 4 hours for oxidation, then heated to 800 °C and calcined by holding at 800 °C for 12 hours. The heating rate was 5 °C / min.

[0042] Characteristic evaluation From the X-ray powder diffraction (XRD) of the formed NMC 811 in Figure 2-1, the formation of a layered structure was confirmed. As shown in Figure 2-2, the scanning electron microscope (SEM) image of the formed NMC 811 (LiNi 0.82 Mn 0.06 Co 0.12 O₂) shows aggregates with a primary particle size of about 1 - 2 μm.

[0043] Example 1 Solid-phase synthesis and characteristic evaluation of LiNi 0.82 Mn 0.06 Co 0.12 O₂ (NMC 811) using Li₂O₂ in an oxygen atmosphere Synthesis In an argon-filled glove box, using a mortar and pestle, 5 grams of the oxide precursor from Comparative Example 1 was mixed and pulverized with 2 grams of Li₂O₂ (Albemarle Corporation) for 10 minutes at a Li to TM molar ratio of 1.30. The mixture was heated in a tubular furnace with a constant oxygen flow at 900 °C for 10 hours. The heating rate and cooling rate were set at 10 °C / min.

[0044] Characteristic evaluation Figures 3-1a and 3-1b show SEM images of NMC 811 formed from Li2O2. No significant differences were observed in surface and morphology compared to NMC 811 of Comparative Example 1 (Figures 1-1a and 1-1b). A comparison of the NMC 811 XRD of the NMC 811 formed in Comparative Example 1 (Figure 1-2) and Comparative Example 2 (Figure 2-2) shows that the NMC synthesized from Li2O2 has the same layered structure as those synthesized from Li2O and LiOH·H2O. Therefore, these results indicate that it is possible to switch the lithium precursor to Li2O or LiOH·H2O or Li2O2.

[0045] Example 2 LiNi using Li2O2 in an argon atmosphere 0.82 Mn 0.06 Co 0.12 Solid-phase synthesis and characterization of O2 (NMC 811) synthesis Pre-oxidation was performed at 900°C for 15 hours to convert the NMC 811 hydroxide precursor to the oxide precursor. In an argon-filled glove box, 5 grams of the oxide precursor were ground together with 2 grams of Li2O2 at a Li-to-TM molar ratio of 1.3 for 10 minutes using a mortar and pestle. The mixture was calcined at 900°C for 10 hours under a constant argon flow. The heating and cooling rates were set to 10°C / min.

[0046] Characteristic evaluation Whole and magnified SEM images of the final particles are shown in Figures 4-1a and 4-1b, respectively, and Figure 4-2 shows a comparison of NMC 811 synthesized in an O2 atmosphere (A) and materials synthesized in an argon atmosphere (B, C). Typically, NMC 811 synthesized in an oxygen stream exhibits a rounded shape with layered characteristics. Products prepared in an Ar stream show different surface morphologies (Figures 4-1a and 4-1b) and lack the characteristic 003 / 104 peak (Figure 4-2). Further XRD refinement also demonstrates that the final product prepared in Ar is a mixture of LNO / Li2O / LCO.

[0047] Example 3 Solid-phase synthesis and property evaluation of LiNi 0.82 Mn 0.06 Co 0.12 O2 (NMC 811) in an Ar atmosphere without gas flow using Li2O2 Synthesis Pre-oxidation was carried out at a constant temperature of 900 °C in oxygen for 15 hours. In an argon-filled glove box, using a mortar and pestle, 5 grams of the oxide precursor was premixed with 2 grams of Li2O2 at a Li to TM molar ratio of 1.3. The mixture was calcined at 900 °C for 10 hours in a tubular furnace. The tube was purged with Ar gas for 10 minutes, the top of the crucible containing the mixture of Li2O2 and the oxide precursor was covered with a cap to prevent direct contact with the gas flow, and after shutting off the gas flow, it was calcined at 900 °C with a heating rate of 10 °C / min for 10 hours.

[0048] Property evaluation The properties of the product are highlighted in Figure 5-1, and the formation of a layered structure is confirmed by XRD of the product. Compared with the typical layered structures described in Comparative Examples 1 and 2, all peaks match the peaks of the typical NMC811 layered structure. With further refinement, the formed product is layered LiMn 0.1 Co 0.1 Ni 0.8 O 1.86 and consists of Li2O and LiMn 0.25 Ni 0.75 O2.

[0049] Example 4 Solid-phase synthesis and property evaluation of LiNi 0.82 Mn 0.06 Co 0.12 O2 (NMC 811) in an oxygen atmosphere without gas flow using Li2O2 Synthesis The compound was synthesized from the transition metal-containing precursor Ni 0.82 Mn 0.06 Co 0.12 (OH)2 and Li2O2. Ni 0.82 Mn 0.06 Co 0.12210 grams of (OH) and 2.61 grams of Li2O2 were introduced into a plastic container at a Li-to-TM molar ratio of 1.05, and acoustic mixing was performed for 1 minute each, gradually increasing the force to 50, 60, and 70 times gravity. After mixing, the mixture was transferred to an alumina crucible and placed in a tubular furnace. The tube was purged with oxygen at room temperature for 10 minutes, and the gas flow was stopped before raising the temperature. Ni 0.82 Mn 0.06 Co 0.12 A mixture of (OH)2 and Li2O2 was oxidized by heat treatment at 500°C for 0 or 4 hours, followed by heating to 800°C and calcination by holding at 800°C for 0, 3, 6 or 12 hours, with a temperature rise rate of 5°C / min (Table 1).

[0050] Characteristic evaluation X-ray powder diffraction (XRD) using a D8 ADVANCE powder diffractometer (Bruker Inc.) with a CuKα anode as the X-ray source (λ=1.54060Å) confirmed that phase-pure NMC 811 was formed under these conditions (Figures 6, 7-1, 8-1, 9-1, and 10-1). SEM images of cross-sections of NMC 811 particles are shown in Figures 7-2, 8-2, 9-2, and 10-2, respectively. [Table 1]

[0051] Electrochemical properties To fabricate electrodes, a cathode laminate was formed by mixing 1% carbon black / carbon nanotubes and 2% PVDF binder with the compound of the present invention. The resulting laminate was then tested in a 2032 coin cell using lithium metal as the counter electrode. The electrolyte consisted of 1.2 M LiPF6 in ethylene carbonate / diethyl carbonate (vol:vol = 3:7) containing 5 wt% fluoroethylene carbonate. Cycles were performed at a rate of C / 20 between 2.9 V and 4.3 V. The charge and discharge curves of the compounds of this disclosure are shown in Figures 11 to 15, and the characteristic charge-discharge curves of NMC 811, which have various charge and discharge capacities and Coulomb efficiencies across different examples, are shown (Figure 16) compared with NMC 811 synthesized using LiOH·H2O or LiOH as a lithium precursor.

[0052] Aspect ratio of primary particles in NMC For the purposes of this disclosure and the appended claims, the aspect ratio is the aspect ratio of the primary particles of a given product (Table 2), and is defined as the average length of the major axis of the particles divided by the average length of the minor axis of the particles, measured from binary cross-sectional SEM images of the products described in Comparative Example 2 and Example 4 (Figures 2-1, 7-2, 8-2, 9-2, and 10-2). The aspect ratio of the particles was calculated for each example and compiled into a table (Table 2 below), which was then plotted on the bar graph shown in Figure 17. [Table 2] As can be seen from the data, the aspect ratio of the embodiments described herein is greater than 1 and less than 2. It has also been evaluated that using Li2O2 (instead of LiOH) in the process of forming NMC811 results in a more compositionally homogeneous NMC811, based on the color differences between primary particles in SEM cross-sectional images.

[0053] Additional aspects of this disclosure The subject matter is described above with reference to numerous aspects and specific examples. In light of the above detailed description, many variations will occur to those skilled in the art. All such obvious variations are fully intended within the scope of the appended claims. Other aspects of the subject matter disclosed herein can include, but are not limited to, the following (aspects are described as "comprising," but alternatively may be described as "consisting essentially of," or "consisting of").

[0054] Aspect 1. A process comprising calcining a mixed metal oxide composition to form a cathode material, wherein the mixed metal oxide composition is formed by mixing (i) a metal-containing precursor and (ii) a lithium precursor comprising lithium peroxide (Li2O2), lithium hydroperoxide (LiOOH), lithium peroxide monoperoxohydrate trihydrate (Li2O2.H2O2.3H2O), or a mixture of any two or more of the foregoing, the metal-containing precursor comprises a compound or mixture of compounds each having formula (I), or an oxide counterpart thereof, qMn(OH)2·(1-q)Ni a Mn b Co c M y X 1+k (I) where 0 ≦ q ≦ 0.8, c = 1 - a - b, 0 ≦ a ≦ 1, 0 < b ≦ 1, 0 ≦ y ≦ 0.05, M comprises one or more selected from the group consisting of Al, Mg, Ti, Mo, Nb, Zr, Hf, Ta, W, B, P, and F, X is OH - , CO3 2- , NO3 - , SO4 2- , C2O4 2- , C2H3O2 - , CHO2 - , selected from the group consisting of stearate, oleate, tartrate, and lactate, and X is OH - , C3H3O2 - , NO3 - [[ID=4- When selected from the group consisting of stearate, oleate and lactate, -0.025 ≦ k ≦ 0.25; when X is otherwise, 0.975 ≦ k ≦ 1.25, The cathode material thus formed contains a compound having the formula (II), qLi2MnO3·(1-q)LiNi a Mn b Co c M y O 2+z (II) where 0 ≦ q ≦ 0.8, c = 1 - a - b, 0 ≦ a ≦ 1, 0 < b ≦ 1, 0 ≦ y ≦ 0.05, -0.025 ≦ z ≦ 0.125, and M is selected from the group consisting of Al, Mg, Ti, Mo, Nb, Zr, Hf, Ta, W, B, P, F and combinations of any two or more of the foregoing, the process.

[0055] Aspect 2. The process according to Aspect 1, wherein in the mixing step, the mole of Li is greater than or equal to the total mole of Ni, Mn and Co.

[0056] Aspect 3. The process according to any one of Aspects 1 to 2, wherein the mixing step is carried out in an atmosphere containing less than 3% by weight of moisture to form the mixed metal oxide composition.

[0057] Aspect 4. The process according to any one of Aspects 1 to 3, wherein the calcination step is carried out by external supply of a gas containing an amount of oxygen in the range of about 0.1 to about 90% by weight.

[0058] [[ID=三十三]]Aspect 5. The process according to any one of Aspects 1 to 3, wherein the calcination step is carried out by external supply of a gas that provides an amount of oxygen such that the molar ratio of the oxygen provided from the external supply of the gas to the mixed metal oxide composition to be calcined is 1:4 or less.

[0059] Aspect 6. The process according to any one of Aspects 1 to 5, wherein the calcination step is carried out in an atmosphere having a moisture content of 3% by weight or less.

[0060] It should be noted that there is an error in the original text. In the translation of "態様33", it should be "Aspect 33" instead of "三十三".Embodiment 7. The process according to any one of Embodiments 1 to 6, wherein the mixing step is performed under ambient temperature and pressure conditions.

[0061] Embodiment 8. The above-mentioned baking process, At temperatures ranging from 500°C to 1200°C, A process described in any one of embodiments 1 to 7, carried out over a period of time ranging from 1 to 24 hours.

[0062] Embodiment 9. The process according to any one of Embodiments 1 to 8, further comprising dehydrating the metal-containing precursor before the mixing step.

[0063] Embodiment 10. The process according to any one of Embodiments 1 to 9, wherein the mixed metal oxide composition is in the form of fine particles with an average particle size of less than 100 microns.

[0064] Embodiment 11. The process according to any one of Embodiments 1 to 10, wherein the cathode material is in the form of fine particles with an average particle size of less than 50 microns.

[0065] Embodiment 12. The process according to any one of embodiments 1 to 11, wherein the mixed metal oxide composition is continuously supplied to a reactor and the cathode material is continuously removed from the reactor, at least partially.

[0066] Embodiment 13. The process according to Embodiment 12, wherein the reactor includes either a rotary reactor or a roller hearth kiln.

[0067] Embodiment 14. The process according to any one of embodiments 1 to 13, wherein the cathode material thus formed has an aspect ratio greater than 1 and less than 2.

[0068] Embodiment 15. A calcined mixed metal oxide composition suitable for forming a cathode material, wherein the composition comprises a compound having the following formula: qLi2MnO3·(1-q)LiNi a Mn b Co c My O 2+z (II) Where 0 ≦ q ≦ 0.8, c = 1 - ab, 0 ≦ a ≦ 1, 0 < b ≦ 1, 0 ≦ y ≦ 0.05, -0.025 ≦ z ≦ 0.125, and M is selected from the group consisting of Al, Mg, Ti, Mo, Nb, Zr, Hf, Ta, W, B, P, F, and combinations of any two or more thereof, the mixed metal oxide composition.

[0069] Aspect 16. The composition according to aspect 15, wherein the composition has an aspect ratio greater than 1 and less than 2.

Claims

1. It is a process, This includes calcining a mixed metal oxide composition to form a cathode material. Here, The mixed metal oxide composition comprises (i) a metal-containing precursor and (ii) lithium peroxide (Li ２ O ２ ), lithium hydroperoxide (LiOOH), lithium peroxide monoperoxohydrate trihydrate (Li ２ O ２ . H ２ O ２ 3H ２ It is formed by mixing a lithium precursor containing O), or a mixture of any two or more of the above, The metal-containing precursor comprises a compound having formula (I), a mixture of such compounds, or an oxide equivalent thereof. 1M.(OH) ２ ・(1-q)Ni ａ Mn ｂ Co ｃ M ｙ X １＋ｋ (I) In the formula, 0 ≤ q ≤ 0.8, c = 1 - a - b, 0 ≤ a ≤ 1, 0 < b ≤ 1, 0 ≤ y ≤ 0.05, M includes one or more selected from the group consisting of Al, Mg, Ti, Mo, Nb, Zr, Hf, Ta, W, B, P and F, and X is OH － CO ３ ２－ NO ３ － SO ４ ２－ , C ２ O ４ ２－ , C ２ H ３ O ２ － , CHO ２ － Selected from the group consisting of stearate, oleate, tartrate, and lactate, where X is OH － , C ３ H ３ O ２ － NO ３ － , CHO ２ － If selected from the group consisting of stearate, oleate, and lactate, then -0.025 ≤ k ≤ 0.25, and if X is otherwise, then 0.975 ≤ k ≤ 1.

25. The cathode material formed in this manner contains a compound having formula (II), 1L) ２ MnO ３ ・(1-q)LiNi ａ Mn ｂ Co ｃ M ｙ O ２＋ｚ (II) The process wherein, in the formula, 0 ≤ q ≤ 0.8, c = 1 - a - b, 0 ≤ a ≤ 1, 0 < b ≤ 1, 0 ≤ y ≤ 0.05, -0.025 ≤ z ≤ 0.125, and M is selected from the group consisting of Al, Mg, Ti, Mo, Nb, Zr, Hf, Ta, W, B, P, F and any two or more combinations thereof.

2. The process according to claim 1, wherein in the mixing step, the moles of Li are equal to or greater than the total moles of Ni, Mn, and Co.

3. The process according to any one of claims 1 to 2, wherein the mixing step is carried out in an atmosphere containing less than 3% by weight of water in order to form the mixed metal oxide composition.

4. The process according to any one of claims 1 to 3, wherein the calcination step is carried out by an external supply of a gas containing oxygen in an amount ranging from about 0.1 to about 90% by weight.

5. The process according to any one of claims 1 to 3, wherein the calcination step is carried out by an external gas supply providing oxygen from an external gas supply in such an amount that the molar ratio of oxygen to the mixed metal oxide composition to be calcined is 1:4 or less.

6. The process according to any one of claims 1 to 5, wherein the aforementioned baking step is carried out in an atmosphere having a moisture content of 3% by weight or less.

7. The process according to any one of claims 1 to 6, wherein the mixing step is performed under ambient temperature and pressure conditions.

8. The aforementioned baking process, At temperatures ranging from 500°C to 1200°C, A process according to any one of claims 1 to 7, carried out over a period of time ranging from one hour to 24 hours.

9. The process according to any one of claims 1 to 8, further comprising dehydrating the metal-containing precursor before the mixing step.

10. The process according to any one of claims 1 to 9, wherein the mixed metal oxide composition is in the form of fine particles with an average particle size of less than 100 microns.

11. The process according to any one of claims 1 to 10, wherein the cathode material is in the form of fine particles with an average particle size of less than 50 microns.

12. The process according to any one of claims 1 to 11, wherein the mixed metal oxide composition is continuously supplied to a reactor, and the cathode material is continuously removed from the reactor, at least partially.

13. The process according to claim 12, wherein the reactor includes either a rotary reactor or a roller hearth kiln.

14. The process according to any one of claims 1 to 13, wherein the cathode material has an aspect ratio greater than 1 and less than 2.

15. A calcined mixed metal oxide composition suitable for forming a cathode material, wherein the composition comprises a compound having the following formula: 1L) ２ MnO ３ ・(1-q)LiNi ａ Mn ｂ Co ｃ M ｙ O ２＋ｚ (II) The mixed metal oxide composition wherein, in the formula, 0 ≤ q ≤ 0.8, c = 1 - ab, 0 ≤ a ≤ 1, 0 < b ≤ 1, 0 ≤ y ≤ 0.05, -0.025 ≤ z ≤ 0.125, and M is selected from the group consisting of Al, Mg, Ti, Mo, Nb, Zr, Hf, Ta, W, B, P, F and any two or more combinations of the above.

16. The composition according to claim 15, wherein the composition has an aspect ratio greater than 1 and less than 2.

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