Substitutional Lithium-Excess Cathode Materials

Abstract

Various embodiments provide rapid and cost-effective methods for forming crystallographically stable, highly durable, cobalt-free lithium-substituted lithium-rich metal oxide (S-LRMO) materials, where the lithium-substituting elements are a combination of Na, K, Ca, and Mg, in amounts above what is generally considered doping. In some embodiments, cathode active materials are provided that include lithium-substituted lithium-rich metal oxides. For example, in some embodiments, the cathode active material has the formula: Li[Li x A y M z ]O b wherein A includes at least one of Na, K, Ca, and / or Mg. In some embodiments, (x+y) is greater than 0 and less than 0.3, y>0.05, z=1-(x+y), M includes Mn and Ni, and b is greater than or equal to 1.8 and less than or equal to 2.2.

Description

[Technical Field]

[0001] Related Applications This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 63 / 482,654, filed February 1, 2023, entitled "Substituted Lithium-Rich Cathode Material," and U.S. Provisional Patent Application No. 63 / 596,222, filed November 3, 2023, entitled "Substituted Lithium-Rich Cathode Material," which are hereby incorporated by reference for all purposes.

[0002] Lithium-containing electrode materials and associated synthesis methods are generally described. [Background technology]

[0003] Aspects of the present invention relate to substituted lithium-rich lithium nickel manganese oxide cathode materials and methods of making the same, and in particular to various embodiments of active materials in which a portion of the lithium is substituted with one or more alkali metal and / or alkaline earth metal elements.

[0004] Cobalt-containing cathode materials (or positive electrode materials) in lithium-ion batteries account for a significant portion of the cost of modern battery cells, with cobalt being the primary cost driver. The complex cobalt supply chain contributes to volatile cobalt prices. This creates a need for reliable cobalt-free lithium-ion battery cathode materials. Similarly, the cost of lithium has risen significantly in recent years. Therefore, reducing the lithium content of cathode materials while maintaining electrochemical performance is of great interest. Improved materials and manufacturing methods are therefore needed. Summary of the Invention

[0005] The subject matter of this invention includes possibly interrelated products, alternative solutions to a particular problem, and / or a plurality of different uses of one or more systems and / or articles.

[0006] According to various embodiments, the method includes sintering a substituted lithium-rich metal oxide (S-LRMO) material at a sintering temperature to form a sintered S-LRMO material; and quenching the S-LRMO material from the sintering temperature to room temperature in less than 500 milliseconds to form a sintered S-LRMO material having the formula: Li x A y M z ]O b (Wherein A contains at least one of Na, K, Ca, or Mg, (x+y) is greater than 0 and less than 0.3, y>0.05, z=1-(x+y), M includes Mn and Ni, and b is in the range of 1.8 to 2.2) In some embodiments, during and / or after synthesis of the S-LRMO material, at least a portion of the S-LRMO has a "lithium-rich transition metal oxide" type crystal structure, although the S-LRMO material may include other elements in place of lithium.

[0007] According to various embodiments, the method includes pyrolyzing the precursor material using convection heating, microwave irradiation (e.g., direct microwave irradiation), and / or radiative heating to form a pyrolyzed substituted lithium-rich metal oxide (S-LRMO) material; sintering the pyrolyzed S-LRMO material to form a sintered S-LRMO material; and quenching the sintered S-LRMO material to form a compound having the chemical formula: Li x A y M z ]O b (In the formula, A contains at least one of Na, K, Ca, and Mg, (x+y) is greater than 0 and less than 0.3, y>0.05, z=1-(x+y), M includes Mn and Ni, and b is in the range of 1.8 to 2.2) The method includes a step of forming a quenched S-LRMO material represented by the formula:

[0008] According to various embodiments, the cathode active material has the chemical formula: Li x A y M z "O b (Wherein A is at least one of Na, K, Ca, or Mg; (x+y) is greater than 0 and less than 0.3, y>0.05, z=1-(x+y), M includes Mn and Ni, and b is in the range of 1.8 to 2.2) It is expressed as:

[0009] Other advantages and novel features of the present invention will become apparent from the following detailed description of various non-limiting embodiments of the invention when considered in conjunction with the accompanying drawings. In the event of conflicting and / or inconsistent disclosure between this specification and a document incorporated by reference, the present specification will control. [Brief explanation of the drawings]

[0010] Non-limiting embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, which are schematic and are not intended to be drawn to scale. In the drawings, each identical or nearly identical illustrated component will generally be represented by a single number. For purposes of clarity, not every component will be numbered in every figure, and not every component of each embodiment will be shown unless illustration is necessary for those skilled in the art to understand the invention. In the drawings: The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and, together with the general description given above and the detailed description given below, serve to explain features of the invention. FIG. 1 is a photograph of a rapid cooling system according to various embodiments of the present disclosure. FIG. 2 includes time-lapse images of four consecutive video captures taken at 30 frames per second illustrating the rapid cooling process according to various embodiments of the present disclosure. 3 and 4 show the results of Li where x=1.2, y=0.75 before and after rapid cooling in accordance with various embodiments of the present disclosure. x (Mn y Ni 1-y ) 2-x 1 is a graph showing the X-ray diffraction (XRD) patterns of the materials, respectively. Figure 5 shows the Li x (Mn y Ni 1-x ) 2-x 1 is a graph showing an X-ray diffraction (XRD) pattern of an O2 material. FIG. 6 shows a Li SiO 2 alloy with x=1.16, y=0.7 processed using microwave heating and ultra-rapid cooling according to various embodiments of the present disclosure. x (Mn y Ni 1-y ) 2-x 1 is a graph showing an X-ray diffraction pattern of an O2 material. FIG. 7A is a transmission electron microscope (TEM) atomic mapping micrograph of a prior art LRMO material that was not rapidly cooled before electrochemical cycling. FIG. 7B is a TEM HAADF atomic mapping micrograph of a rapid-cooled unsubstituted LRMO material prior to electrochemical cycling, according to various embodiments of the present disclosure. FIG. 8A is a graph showing cell potential vs. specific capacity, and FIG. 8B is a graph showing the cell potential vs. specific capacity of a comparative Li x (Mn y Ni 1-y ) 2-x 1 is a graph of specific capacity vs. cycles for O2 materials. Figure 9A is a graph showing cell potential vs. specific capacity during a break-in cycle. Figure 9B is a graph showing cell potential vs. specific capacity over time. Figure 9C is a graph showing cycles vs. specific capacity at a C / 20 rate. Figure 9D is a graph showing discharge specific capacity vs. cycle number at a C / 5 rate, along with a C / 20 reference cycle, based on a comparative embodiment of the present disclosure. FIG. 10 illustrates a method for producing a compound of formula: Li[Li 0.14 Na 0.06 Mn 0.6 Ni 0.2 1 is a chart showing the results of an X-ray diffraction pattern of an S-LRMO active material having ]O2. FIG. 11 illustrates various embodiments of the present disclosure, in which the formula: Li[Li 0.06 Na 0.14 Mn 0.6 Ni 0.2 1 is a chart showing the results of an X-ray diffraction pattern of an S-LRMO active material having ]O2. FIG. 12 illustrates various embodiments of the present disclosure, in which the formula: Li[Li 0.06 K 0.14 Mn 0.6 Ni 0.2 1 is a chart showing the results of an X-ray diffraction pattern of an S-LRMO active material having ]O2. FIG. 13 illustrates various embodiments of the present disclosure, in which the formula: Li[Li 0.06 Na 0.07 K 0.07 Mn 0.6 Ni 0.2 1 is a chart showing the results of an X-ray diffraction pattern of an S-LRMO active material having ]O2. Figure 14 shows the formula: Li[Li 0.14 Na 0.06 Mn 0.6 Ni 0.2 10 is a transmission electron micrograph and EDS elemental map of an S-LRMO material with ]O2, showing that Mn and Ni are evenly distributed throughout the material. FIG. 15 is a chart showing electrochemical data, including charge / discharge performance, of S-LRMO materials according to various embodiments of the present disclosure. FIG. 16 is a chart showing electrochemical data, including charge / discharge performance, of S-LRMO materials according to various embodiments of the present disclosure. FIG. 17 is a chart showing electrochemical data, including cycle life, of S-LRMO materials according to various embodiments of the present disclosure. FIG. 18 is a chart showing electrochemical data, including charge / discharge performance, of S-LRMO materials according to various embodiments of the present disclosure. FIG. 19 is a chart showing electrochemical data, including efficiency as a function of cycle number, for S-LRMO materials according to various embodiments of the present disclosure. 20A-20B are charts showing electrochemical data, including cycle life, of S-LRMO materials according to various embodiments of the present disclosure. FIG. 21 is a chart showing electrochemical data, including charge / discharge performance, of S-LRMO materials according to various embodiments of the present disclosure. FIG. 22 is a chart showing electrochemical data, including charge / discharge performance, of S-LRMO materials according to various embodiments of the present disclosure. FIG. 23 is a chart containing rate capability data for potassium-substituted LRMO materials according to various embodiments of the present disclosure. FIG. 24 shows the results of the material: Li[Li 0.015 Na 0.155 Mn 0.58 Ni 0.25 1 is a chart showing data from the first two charge / discharge cycles of a lithium metal half-cell made with ]O2, showing a specific capacity of over 250 mAh / g at a C / 20 rate. Figure 25 shows the material: Li[Li 0.015 Na 0.155 Mn 0.58 Ni 0.25 1 is a chart showing cycle life data for lithium metal anode half-cells fabricated with ]O2, showing stable capacity retention well above 200 mAh / g and repeated reference cycling. Based on various embodiments of the present disclosure, the mid-discharge voltage is also apparently stable, which is not typical for lithium-rich cathode materials. 26A-26B are charts showing diffusion data obtained from GITT (galvanostatic intermittent titration) of Li[Li] prepared as described, according to one embodiment. 0.015 Na 0.155 Mn 0.58 Ni 0.25 ]O2, at least in some respects, is a potential source of lithium ion transport for Li[Li 0.16 Mn 0.58 Ni 0.25 ] shows that it is superior to that of O2 material. 27A and 27B are a chart (FIG. 27A) showing diffusion data obtained from constant current intermittent titration (GITT) and a chart (FIG. 27B) showing rapid pulse resistance. The chart (FIG. 27A) showing diffusion data is for Li2+ prepared as described in accordance with one embodiment. 1.081 Na 0.057 Mn 0.652 Ni 0.21 It is possible that the lithium ion transport capacity of O2 is at least in some respects lower than that of Li at low states of charge. 1.17 Mn 0.58 Ni 0.25 The chart showing the high-speed pulse resistance (Fig. 27B) shows that the Li 1.17 Mn 0.58 Ni 0.25 Li compared to O2 1.081 Na 0.057 Mn 0.652 Ni 0.21 Figure 1 shows the fast pulse resistance of the same test cell (14 mm diameter circular electrodes) in O2. 28A-28C show the sodium-substituted S-LRMO materials (Li 1.081 Na 0.057 Mn 0.652 Ni 0.21 28A and 28B are plots showing the long-term (320 cycles) cycling stability of 02 (C / 3 daily cycles, C / 15 reference cycles every 25 cycles): FIG. 28A shows the capacity stability (C / 3 daily cycles, C / 15 reference cycles every 25 cycles); FIG. 28B shows the average discharge potential; and FIG. 28C shows the coulombic efficiency.

[0011] Detailed Description According to various embodiments, a rapid and inexpensive method for forming crystallographically stable, durable, cobalt-free lithium-substituted lithium-rich metal oxide (S-LRMO) materials is provided. The elements used to substitute for lithium are some combination of Na, K, Ca, and Mg, in amounts above what is generally considered doping. In some embodiments, a cathode active material is provided that includes a lithium-substituted, lithium-rich metal oxide. For example, in some embodiments, the cathode active material has the formula Li[Li x A y M z ]O b and A includes at least one of Na, K, Ca, or Mg. Such methods and materials are described in detail below.

[0012] In the context of the present disclosure, it is recognized that in at least some lithium-containing positive electrode materials, it is of interest to explore materials that can replace lithium in the material without substantially adversely affecting the properties of the material (e.g., without significantly changing the crystal structure or performance of the material).

[0013] LRMO material The following section describes techniques for preparing unsubstituted LRMO materials, which can provide insight into the substituted LRMO materials (S-LRMO materials) described in detail below. In the context of this disclosure, it is recognized that in some embodiments, the techniques and conditions described below for the unsubstituted LRMO materials can be used to prepare S-LRMO materials (e.g., when resulting in S-LRMO materials that exhibit advantageous and desirable crystallographic / structural and electrochemical performance properties).

[0014] In some embodiments, unsubstituted LRMO materials (e.g., LRMO materials that do not contain alkali or alkaline earth metals substituting Li) have the following general formula 1: Li x (Mn y Ni 1-y ) 1-x O2(1) (wherein x is 0 or more and 0.3 or less, y is greater than or equal to 0.1 and less than or equal to 0.95, e.g., greater than or equal to 0.5 and less than or equal to 0.8) It can be expressed as:

[0015] In some embodiments, the unsubstituted LRMO material is a lithium-rich, lithium manganese nickel oxide material, represented by Formula 2: Li (1 / 3-2x / 3) Mn (2 / 3―x / 3) Ni x ]O2(2) (wherein x is 0.1 or more and 0.4 or less) It can be expressed as:

[0016] In its initial state (e.g., before the first charge), the unsubstituted LRMO material may, in some embodiments, have a distinct hexagonal (e.g., rhombohedral) and monoclinic phase. Thus, in some embodiments, the LRMO material has the formula: (1-x)[Li2MnO3]*x[LiMn a Ni (1-a) O2] where the first part of the formula represents the relative molar amount of monoclinic phase (1-x) and the second part represents the relative molar amount of rhombohedral phase (x). In some embodiments, the mole fraction "x" of the rhombohedral phase generally ranges between 0.8 and 0.95, and "a" is greater than or equal to 0.6 and less than or equal to 0.9. In some embodiments, the two phases may be arranged in a layered structure.

[0017] Various embodiments can provide unsubstituted LRMO materials that exhibit high specific capacity (e.g., >240 mAh / g) and a wide functional voltage window (e.g., ≥2.0 V, ≤4.8 V) when used as the active material in cobalt-free cathodes.

[0018] According to various embodiments, methods for forming unsubstituted LRMO materials include rapid thermal processing and rapid (e.g., less than 10 seconds) or ultra-rapid (e.g., 500 milliseconds or less) cooling, resulting in LRMO materials with excellent crystalline structures with desirable atomic order / disorder. Such properties can lead to unexpectedly robust long-term stability and performance when used as cathode active materials.

[0019] Certain unsubstituted LRMO materials (e.g., those synthesized without quenching and / or water quenching) may be unsuitable for use as cathode active materials due to poor rate capability and / or poor capacity retention. This may be due, for example, to structural instability caused by oxygen loss, migration of transition metal ions during use, and / or the potential for manganese leaching. Without wishing to be bound by theory, the two most common degradation mechanisms manifest themselves as a decrease in average discharge voltage due to the gradual rearrangement of the material to a predominantly spinel structure, and a decrease in capacity during cycling due to mechanical and / or chemical degradation of the material.

[0020] Pyrolysis and processing of unsubstituted LRMO materials LRMO materials, including substituted and unsubstituted LRMO materials, can be synthesized from precursor materials by a variety of methods. Table 1 below includes specific methods that can be used to synthesize LRMO materials, including precursor synthesis, precursor materials, quenching methods, performance indices, and discharge capacities (DC) of LRMO material cathodes.

[0021] [Table 1]

[0022] As shown in Table 1, the three main synthetic routes for LRMO materials include precipitation followed by combustion, hydrothermal synthesis, and sol-gel solution generation with intermediate temperature decomposition and high temperature thermal treatment (e.g., calcination, annealing, sintering).

[0023] As shown in Table 1, studies investigating the effect of nickel composition on LRMO cathode performance have decreased over the years and focused on multiple nickel compositions or those with the formula: Li[Ni x Li (1 / 3-2x / 3) Mn (2 / 3-x / 3) Only a few studies have examined nickel compositions with x less than 0.2 in cathodes with ]O2. Table 1 also shows that there are significant discrepancies in the synthetic routes employed in these studies. Furthermore, there are few studies that provide a detailed comparative assessment of the effect of synthetic techniques on the performance of LRMO cathodes. The ordering and disordering of transition metals in LRMO materials can be important, and both composition and synthetic technique can provide mechanisms for influencing the degree of structural ordering and disordering. The electrochemical behavior that these compositional and synthetic changes can result in, such as different defect concentrations, can have a significant impact on LRMO cathode properties.

[0024] Without wishing to be bound by theory, it is believed that when a sample is quenched in liquid nitrogen, the particles are immediately enveloped in an insulating envelope of nitrogen gas, similar to the Leidenfrost effect, which significantly reduces the rate of heat transfer. In the preparation of certain conventional cathode materials, it is believed that lithium-containing cathode materials for lithium-ion batteries should not come into contact with moisture because water dissolves lithium from the cathode material and forms a coating of lithium hydroxide on the material. Furthermore, water is known to cause failures in lithium-ion batteries, such as lithium-ion batteries containing lithium iron phosphate cathode materials.

[0025] Without wishing to be bound by theory, the inventors believe that conventional, relatively slow quenching and cooling processes cause metal oxide agglomeration, resulting in the formation of separate phases of nickel oxide and lithium manganese oxide. In particular, the nickel oxide phase may reside condensed on the surfaces of LRMO material particles (e.g., crystalline grains). Without wishing to be bound by theory, such surface nickel oxide agglomeration, and the segregation of nickel and manganese in the crystalline structure generally, may be at least partially responsible for the chemical instability of conventional LRMO active materials.

[0026] In contrast, the present inventors have unexpectedly discovered that water quenching does not adversely affect LRMO cathodes and does not result in lithium dissolution from such LRMO cathodes. An exemplary embodiment of water quenching using unsubstituted LRMO is described in U.S. Patent Application Publication No. 2023 / 0015455 (published January 19, 2023, and filed July 5, 2022 as U.S. Patent Application No. 17 / 810,722, entitled "Lithium-Rich Nickel Manganese Oxide Battery Cathode Materials and Methods"), which is incorporated herein by reference in its entirety. Water quenching induces evaporation in the form of bubble nucleation and dissipation, which is believed to substantially enhance the rate of heat transfer. Therefore, water quenching is believed to potentially have a heat transfer rate roughly two orders of magnitude greater than liquid nitrogen quenching. Additionally, water and water-solvated additives (i.e., other materials that can dissolve in water) can react with LRMO during and after quenching at elevated temperatures to form beneficial surface terminations and / or coatings that enhance electrochemical stability and durability when used in lithium-ion batteries. As described in more detail below, the methods, conditions, parameters, and / or processing steps described above can, in some embodiments, be applied to the substituted LRMO materials described in this disclosure.

[0027] Furthermore, in the context of Table 1 above, in many of the prior art quenching processes described above, quenching is performed on sintered or partially sintered pellets of material that are still compacted into larger chunks (e.g., centimeters in width). In contrast, in some embodiments of the present disclosure, quenching is performed on loose and / or crushed powders having particles and / or aggregates with an average diameter of 20 μm or less, such that when the particles contact the quenching liquid (e.g., water), the entire material cools rapidly and at approximately the same rate. For example, the average diameter may be 0.1 μm or more and 20 μm or less, e.g., 0.1 μm or more and 1 μm or more, or 1 μm or more and 20 μm or less. Other ranges are possible. Each aggregate may contain crystallites with an average size of 25 nm or more and 500 nm or less, e.g., 50 nm or more and 200 nm or less. Other ranges are also possible. Each crystallite may comprise a single crystal of the LRMO material. The crystallites may be partially fused or fully fused within the aggregate. When the crystallites are completely fused within an agglomerate (i.e., within a powder particle), each crystallite may comprise a single crystal grain of the powder particle, separated from other single crystal grains within the same powder particle by a grain boundary. The average grain dimension of the powder particle may be 25 nm or more and 500 nm or less, e.g., 50 nm or more and 200 nm or less. Other ranges are also possible. The agglomerate may be relatively porous, allowing water to reach the crystallites within the agglomerate.

[0028] In some embodiments, the material (e.g., LRMO or S-LRMO, as described below) subjected to quenching comprises a powder (e.g., loose powder) comprising particles having an average maximum cross-sectional dimension of 20 μm or less, 10 μm or less, 5 μm or less, 2 μm or less, or smaller. In some embodiments, the material (e.g., LRMO or S-LRMO, as described below) subjected to quenching comprises a powder (e.g., loose powder) comprising particles having an average maximum cross-sectional dimension of 0.1 μm or more, 0.2 μm or more, 0.5 μm or more, 1 μm or more, or larger. As noted above, combinations of these ranges are possible. Other ranges are also possible. In some embodiments, the material (e.g., LRMO or S-LRMO, as described below) subjected to quenching comprises a powder (e.g., loose powder) comprising particles including agglomerates of crystallites having an average maximum cross-sectional dimension of 25 nm or more, 50 nm or more, 100 nm or more, or larger. In some embodiments, the material subjected to quenching (e.g., LRMO or S-LRMO, as described below) comprises a powder (e.g., loose powder) comprising agglomerates of crystallites having an average maximum cross-sectional dimension of 500 nm or less, 300 nm or less, 200 nm or less, or smaller. Combinations of these ranges are possible. Other ranges are also possible. The average maximum cross-sectional dimension of the particles and / or crystallites can be determined, for example, by transmission electron microscopy.

[0029] Rapid and ultra-rapid cooling of LRMO materials According to various embodiments, the LRMO cathode active material can be formed by heat-treating (e.g., sintering, calcinating, and / or annealing) and quenching a powder of LRMO material. In particular, the heat-treating process can include a high-temperature process in which the LRMO material is heated to a processing temperature of 800°C or more and 1000°C or less. For example, the temperature can be 850°C or more and 950°C or less, or 900°C or more. Other ranges are possible. The heat-treating process can be carried out in a heat-treating device such as any suitable furnace, for example, a tube furnace, a muffle box furnace, a rotary hearth kiln, a belt furnace, or the like. In some embodiments, the heat-treating process can optionally include one or more low-temperature precursor decomposition processes (e.g., firing), in which the LRMO material can be heated to a temperature above room temperature and less than 800°C. For example, firing can include heating the LRMO material to 450°C or more and 550°C or less, for example, 500°C, prior to the high-temperature processing. Other ranges are possible.

[0030] According to various embodiments, the quenching process may include transferring the heated LRMO material to a quench bath. For example, the LRMO material may be transferred from a thermal processing device directly to the quench bath. As described in more detail below, the methods, conditions, parameters, and / or process steps described above may, in some embodiments, be applied to the substituted LRMO materials described herein.

[0031] In prior art methods, the LRMO material may cool slowly during transfer from the furnace. For example, the transfer process may take up to 10 seconds, during which time the temperature of the LRMO material may gradually decrease. The inventors have found that slow cooling before entering the quench bath can cause undesirable changes to the crystal structure of the sintered LRMO material. In other words, the temperature at which the sintered LRMO material enters the quench bath can be important for obtaining the desired crystal structure. For example, slow cooling can result in a less favorable crystal structure.

[0032] According to various embodiments, the transfer process may be configured such that, after sintering, the sintered LRMO material enters the quench bath at a temperature of at least 800°C, e.g., at least 800°C and no greater than 950°C, or at least 850°C and no greater than 925°C, or 900°C. For example, the transfer time from the heat treatment device to the quench bath may be limited to 10 seconds or less, e.g., 1 second or less, e.g., less than 0.5 seconds, or 0.2 seconds or less. Thus, the sintered LRMO material is cooled from the heat treatment temperature (e.g., a sintering temperature of at least 800°C, e.g., at least 800°C and no greater than 950°C, or at least 850°C and no greater than 925°C, or 900°C) to room temperature (e.g., 25°C) in 10 seconds or less, e.g., less than 0.5 seconds, including no greater than 0.2 seconds. Other ranges are possible. As used herein, an "ultra-rapid cooling process" can have a cooling time of less than 0.5 seconds, e.g., 0.2 seconds or less, e.g., 0.1 seconds or more and 0.2 seconds or less, and a "rapid cooling process" can have a cooling time of 10 seconds or less, e.g., 0.5 seconds or more and 10 seconds or less. Other ranges are possible.

[0033] The sintered LRMO powder particles may be quenched in a quench bath at an average rate of at least 50°C / s, e.g., at least 50°C / s and no more than 10,000°C / s. For example, the sintered LRMO powder particles may be quenched at a rate of at least 87.5°C / s and no more than 8,750°C / s, e.g., at least 1,750°C / s, e.g., at least 1,750°C / s and no more than 8,750°C / s, or at least 4,375°C / s and no more than 8,750°C / s. Other ranges are possible. Thus, the sintered LRMO material may be quenched from a heat treatment temperature (e.g., a sintering temperature) of at least 800°C to the temperature of the quench bath (e.g., a room temperature water bath at 25°C) in 10 seconds or less, e.g., less than 500 milliseconds, 400 milliseconds or less, 300 milliseconds or less, or 200 milliseconds or less. For example, the quenching may occur in 100 milliseconds or less, 400 milliseconds or less, or in a time period of at least 100 milliseconds and no more than 200 milliseconds. Other ranges are possible. As described in more detail below, the methods, conditions, parameters and / or process steps described above may, in some embodiments, be applied to the substituted LRMO materials described herein.

[0034] The quench bath may include a high specific heat liquid solvent having a vaporization temperature less than 200°C. For example, the quench bath may include a solvent such as water, oil, and / or alcohol. In some embodiments, the quench bath may include an additive configured to modify the surface of the LRMO material during quenching to improve the long-term chemical stability of the material. The additive may include an acid, a base, an alcohol, and / or a dissolved carbon species (e.g., an acid, an alcohol, or a carbon species dissolved in water).

[0035] For example, the quench bath may be an aqueous quench solution containing at least 0.01 moles / liter and at most 1.0 moles / liter, e.g., at least 0.1 moles / liter and at most 1.0 moles / liter, or at least 0.5 moles / liter and at most 1.0 moles / liter, of an acid additive (e.g., sulfuric acid, hydrochloric acid, nitric acid, oxalic acid, citric acid, acetic acid, phosphoric acid, orthophosphoric acid, lithium hydroxide, sodium hydroxide, potassium hydroxide, combinations thereof, etc.). Other ranges are possible. The acid may be configured to stabilize the surfaces of the LRMO powder particles by reacting with and / or passivating dangling bonds and / or OH end groups of the LRMO powder particles that are quenched in water with the acid additive.

[0036] In some embodiments, acid quenching can form a spinel structure (e.g., a surface layer) on the surface of the quenched LRMO powder particles. The spinel structure can form a framework that stabilizes the particles and provides a three-dimensional pathway for lithium diffusion. In particular, the acid is believed to cause an exchange of lithium ions from the particles with hydrogen ions from the acid, resulting in a subsequent structural transformation of the particle surface and the formation of a spinel surface layer.

[0037] In other embodiments, the quenching solution may include an alcohol and / or a carbohydrate additive in addition to or instead of the acid additive. For example, the alcohol may include isopropyl alcohol or other alcohols, and the carbohydrate may include a sugar, such as fructose, galactose, glucose, lactose, maltose, sucrose, or a combination thereof. In some embodiments, the quenching solution may include a carbohydrate additive in an amount of 0.01 mol / L or more and 1.0 mol / L or less, e.g., 0.1 mol / L or more and 1.0 mol / L or less, or 0.5 mol / L or more and 1.0 mol / L or less. Other ranges are possible. In some embodiments, the carbohydrate may form a dense amorphous carbon coating on the surface of the LRMO powder particles during the quenching process in water containing the carbohydrate particles. Without wishing to be bound by theory, the carbon coating may advantageously be permeable to Li ions while being impermeable to the electrolyte of a lithium-ion battery. The carbon coating may also allow for volumetric changes in the LRMO crystallites during charging and discharging of the battery. As described in more detail below, the methods, conditions, parameters and / or processing steps described above may, in some embodiments, be applied to the substituted LRMO materials described herein.

[0038] Rapid or ultra-rapid cooling processes can produce quenched LRMO materials with crystalline structures that have unexpected durability and electrical properties. In particular, the degree of crystalline order in quenched LRMO materials (e.g., lithium-rich lithium manganese nickel oxides) produced by quenching processes can provide performance characteristics suitable for use as cathode active materials in lithium-ion batteries, providing energy densities and charge storage stability similar to those of cathodes comprising high-nickel-content active materials containing cobalt.

[0039] The quenching process can produce a quenched LRMO material powder having a desired crystal structure and particle size. For example, the quenched, sintered LRMO material can be a loose powder having an average particle size of 1 μm or less, e.g., 0.02 μm or more to 1 μm or less, or 0.05 μm or more to 0.5 μm or less. Other ranges are possible. In some embodiments, the quenched LRMO material can include crystalline phases and / or crystallites having an average crystal size of 25 nm or more to 500 nm or less, e.g., 50 nm or more to 300 nm or less. Each powder particle can include one crystallite or more than one crystallite. The sintered and quenched loose powder particles can be incorporated into a binder (e.g., a carbon binder) to form a cathode electrode for a lithium-ion battery. Other ranges are possible.

[0040] In some embodiments, the sintered and / or quenched LRMO material (or the sintered and / or quenched S-LRMO material described below) comprises a loose powder comprising particles having an average maximum cross-sectional dimension of 1 μm or less, 0.5 μm or less, or smaller. In some embodiments, the sintered and / or quenched LRMO material (or the S-LRMO material described below) is a loose powder comprising particles having an average maximum cross-sectional dimension of 0.02 μm or more, 0.05 μm or more, 0.1 μm or more, 0.2 μm or more, or larger. Combinations of these ranges are also possible (e.g., 0.02 μm or more and 1 μm or less, or 0.05 μm or more and 0.5 μm or less). Other ranges are also possible.

[0041] In some embodiments, the sintered and / or quenched LRMO material (or the sintered and / or quenched S-LRMO material described below) comprises a loose powder comprising particles having crystalline phases and / or crystallites with an average maximum cross-sectional dimension of 500 nm or less, 300 nm or less, 200 nm or less, or smaller. In some embodiments, the sintered and / or quenched LRMO material (or the sintered and / or quenched S-LRMO material described below) comprises a loose powder comprising particles having crystalline phases and / or crystallites with an average maximum cross-sectional dimension of 25 nm or more, 50 nm or more, 100 nm or more, 150 nm or more, or larger. Combinations of these ranges are also possible (e.g., 25 nm or more and 500 nm or more, or 50 nm or more and 300 nm or more). Other ranges are also possible.

[0042] In some embodiments, the quenched LRMO material may be dried to form an LRMO active material (e.g., heat-treated and quenched loose powder particles), and the active material may have a hexagonal primary phase and a monoclinic secondary phase. Thus, the ratio of hexagonal phase content to monoclinic phase content may be greater than 1, e.g., at least 2, e.g., 2 to 20. For example, the sintered and quenched LRMO material (e.g., dried active material) may have a superlattice structure in which layers of the hexagonal primary phase are separated by intermediate layers of the monoclinic secondary phase. Alternatively, the sintered and quenched LRMO material may comprise a hexagonal phase matrix containing monoclinic phase nanozones (i.e., regions less than 1 μm wide). Mn and Ni may be uniformly distributed within the crystal structure of the LRMO material (e.g., excess Mn, Ni, and Li are uniformly and evenly distributed at transition metal crystal lattice sites). For example, the crystal grains of the sintered and quenched LRMO material can exhibit a uniform distribution of Mn and Ni atoms throughout the crystal grain, such that there are no Ni-rich or Mn-rich regions when viewed with high-angle annular dark-field (HAADF) energy-dispersive X-ray spectroscopy (EDS) in a transmission electron microscope (i.e., an EDS elemental map of an HAADF transmission electron microscope image). In one embodiment, the term "no regions that are Ni-rich or Mn-rich" means that there is no crystal volume in the crystal grain larger than 3x3x3 nm that has a difference in the ratio of Ni and Mn atoms of more than 3% compared to the average ratio of Ni and Mn atoms throughout the crystal grain.

[0043] The crystalline structure of the formed LRMO active material may change upon electrochemical cycling. For example, when the active LRMO material is included as the active material in an electrochemical cell, the monoclinic phase may not be present at detectable levels after the first charge-discharge cycle. It is believed that the monoclinic phase may be consumed during Li-ion insertion and / or extraction. As described in more detail below, the methods, conditions, parameters, and / or processing steps described above may, in some embodiments, be applied to the substituted LRMO materials described herein.

[0044] Rapid precursor decomposition in lithium-unsubstituted LRMO materials. LRMO materials can be formed from a variety of precursor materials. For example, the precursor materials can be metal-organic compounds that include a metal, such as Li, Mn, and / or Ni, and a solubilizing agent, such as an organic ligand. For example, the precursor materials can include metal acetates, carbonates, nitrates, sulfates, and / or hydroxides.

[0045] In various embodiments, LRMO materials can be formed by pyrolyzing a precursor material, followed by sintering and quenching the pyrolyzed LRMO material. The precursor material may include a gel formed by a sol-gel process. The gel may include a non-flowable material network (e.g., a colloidal or polymeric network) that has a relatively low yield stress and is expanded throughout its entire volume by a fluid (e.g., a liquid such as water). The gel may include a network formed by covalent bonding or other mechanisms, such as physical aggregation. The sol-gel process may involve converting a monomer into a colloidal solution (sol) that can serve as a precursor to a gel (e.g., a gel of discrete particles or a network polymer). The inventors have discovered that rapid decomposition of the precursor material gel can improve the homogeneity of the LRMO material. For example, in the sol portion of the sol-gel process, stoichiometric amounts of precursors containing Li, Mn, and Ni may be mixed with water to form an aqueous mixture. For example, stoichiometric amounts of Li(CH3COO)*2H2O, Mn(CH3COO)2*4H2O, and Ni(NO3)2*6H2O may be mixed to form an aqueous mixture. However, the present disclosure is not limited to specific precursor materials. For example, in some embodiments, all acetate precursors or all nitrate precursors (i.e., nitrates of lithium, manganese, and nickel) may be used. In some embodiments, the mixture may include an excess of lithium acetate precursor in a mole fraction of 0.01 or more and 0.20 or less to compensate for lithium loss during processing. Other ranges are possible.

[0046] The mixture may then be heated to form a precursor gel. For example, the mixture may be heated to a temperature of at least 90° C. and not more than 150° C., e.g., 100° C., for a time sufficient for gelation to occur. Other ranges are possible.

[0047] The gel may then be pyrolyzed, for example, by heating the gel at a temperature and for a time sufficient to remove (e.g., volatilize and / or decompose) the solubilizing agent (e.g., the organic ligands and / or solvent of the gel) and form a pyrolyzed LRMO material.

[0048] Pyrolysis may be carried out using conventional furnaces such as muffle boxes and / or tubular furnaces. However, such equipment typically has slow heating and cooling rates, on the order of greater than 1°C per minute and less than 10°C per minute, and does not employ any type of direct radiant heat energy input. As such, conventional furnaces can require at least 8 hours of processing time and significant amounts of energy to form pyrolyzed LRMO material.

[0049] According to various embodiments, a rapid (e.g., fast) heating method is used to form the pyrolyzed LRMO material. For example, some embodiments may use microwave irradiation to thermally treat the LRMO precursor material (i.e., to rapidly decompose an LRMO precursor, such as a gel precursor formed by a sol-gel process). For example, the microwave irradiation may be direct microwave irradiation. Other forms of heating suitable for at least some embodiments include, but are not limited to, convective heating and / or radiative heating. A combination of heating methods may also be used. For example, pyrolysis may include convective heating, microwave irradiation (e.g., direct microwave irradiation), and / or radiative heating.

[0050] Microwaves are defined as electromagnetic radiation with wavelengths greater than or equal to 1 mm and less than or equal to 1 m. Widely adopted domestic microwave ovens use microwave radiation at a frequency of approximately 2.45 GHz. Regulations limit the microwave frequencies available for domestic and industrial use. The mechanisms of microwave heating are thought to fall into two categories: 1) current flow in the presence of an external electric field generated by microwave radiation generates heat through the Ohmic effect; and 2) dipoles present in ceramics reorient under a changing electric field, generating heat through friction.

[0051] Microwave heating can achieve lower thermal processing (e.g., precursor pyrolysis) temperatures. Microwave heating can also achieve shorter heating times due to very rapid localized heating compared to conventional furnace heating processes. Intimate mixing of precursor materials can also achieve more efficient volumetric heating than conventional furnace heating processes.

[0052] In some embodiments, microwave heating is used to heat and decompose precursor materials to form pyrolyzed LRMO materials. For example, the precursor materials may contain ligands and / or metals that are highly sensitive to microwave radiation. Therefore, various embodiments utilize microwave radiation to heat precursors and / or precursor gels to very high temperatures in very short periods of time. It has also been found that microwave heating can provide very uniform heat distribution. Therefore, the use of microwave irradiation can dramatically change the heating rate and the texture and / or structure of the resulting pyrolyzed LRMO materials. For example, microwave heating of a precursor gel can produce very homogeneous pyrolyzed LRMO materials. The pyrolyzed LRMO materials can be in the form of inorganic ash and free of organic components (e.g., free of carbon or containing only unavoidable amounts of carbon). Therefore, microwave heating allows for the formation of pyrolyzed LRMO materials without the need for a separate furnace calcination, which may be omitted.

[0053] For example, a precursor gel can be fed into a microwave oven, where microwave irradiation can be used to decompose the gel and form pyrolyzed LRMO material. For example, microwave irradiation can be used to heat the gel to a temperature of at least 350°C, e.g., 350°C or higher and 500°C or lower, for a time sufficient to volatilize the ligands and / or solvents in the gel and form pyrolyzed LRMO material (e.g., LRMO inorganic ash). Other ranges are possible. In various embodiments, pyrolyzed LRMO material can be formed using continuous or pulsed microwaves at a power level of 20,000 W or less per kg of microwave-irradiated material for a time of 30 minutes or less, e.g., 15 minutes or more and 30 minutes or less. Other ranges are also possible. Thus, microwave-based heating processes can be configured to rapidly remove (e.g., vaporize and / or burn) organic components from precursor species to form pyrolyzed LRMO material with improved structural properties, such as homogeneous cation and / or metal oxide distribution.

[0054] While microwave pyrolysis of a precursor gel formed by a sol-gel process has been described above, in other embodiments, the precursor to be pyrolyzed by microwaves may be formed by other methods. For example, alternative precursor preparation methods may include mechanical grinding / mixing, freeze-drying, rotary evaporation, or co-precipitation. Another example of an alternative precursor preparation method is the use of a static convection oven. In one embodiment of the co-precipitation method, a co-precipitated precursor containing hydroxides of Mn and Ni is mixed with lithium and / or other alkali or alkaline carbonates and / or hydroxides. The resulting mixture may be thoroughly mixed and heat-treated. In one embodiment of the co-precipitation method, a precursor containing hydroxides of Mn and Ni may be mixed with lithium carbonate and co-precipitated. For example, solid precursor materials including Li2CO3 or LiOH, nickel oxide, and manganese oxide may also be used. Precursors prepared by any of these methods may also be subjected to microwave pyrolysis to form pyrolyzed LRMO materials (i.e., LRMO inorganic ash). As described in more detail below, the methods, conditions, parameters and / or processing steps described above may, in some embodiments, be applied to the substituted LRMO materials described herein.

[0055] The pyrolyzed LRMO material (i.e., LRMO inorganic ash) may then be mixed and ground (e.g., milled) to form a precursor LRMO powder. The precursor LRMO powder may then be heat-treated (e.g., sintered) in a suitable heat-treating device, such as a tube furnace, muffle box, or other furnace, to form a sintered LRMO material. For example, the precursor LRMO powder material may be heated (e.g., sintered) to a heat-treating temperature (e.g., a temperature of at least 800°C, e.g., 900°C) for a period of 12 hours or more and 24 hours or less, and then rapidly or ultra-rapidly cooled as described above to form a quenched LRMO material. The quenched LRMO material may then be dried and, optionally, re-ground (e.g., milled) to form an LRMO active material (e.g., a cathode active material powder). This LRMO active material powder may then be mixed with a binder or other inert cathode material to form a cathode for a lithium-ion battery.

[0056] According to various embodiments, methods for forming LRMO materials can include combining rapid heating, such as microwave heating, for at least a portion of the heat treatment, with rapid or ultra-rapid cooling, thereby producing LRMO materials with unexpectedly high performance. In particular, this process can produce LRMO materials with high atomic / cationic disorder / homogeneity (quantifiable using X-ray diffraction) and no or substantially no surface segregation of nickel or nickel oxide within the particles (e.g., crystallites) (as observed by transmission electron microscopy). The combination of these material properties produces cathode active materials that exhibit little or no capacity degradation over 100 to 1000 charge / discharge cycles, substantially reduced or no average discharge voltage loss during cycling, and rate capabilities suitable for commercial applications.

[0057] According to various embodiments, embodiment methods including microwave heating and / or rapid / ultra-rapid cooling steps can be used to form LRMO active materials that do not suffer from the chemical instability problems of prior art LRMO materials. In particular, rapid or ultra-rapid cooling steps can be used to form LRMO active materials with reduced Ni surface segregation and increased structural homogeneity compared to conventional LRMO materials that are sintered and then slowly cooled. In various embodiments, the microwave heating process described above may be used in conjunction with rapid or ultra-rapid cooling to form the LRMO active material. For example, pyrolyzed LRMO materials formed using microwave decomposition may be sintered and then subjected to a rapid or ultra-rapid cooling process. As described in more detail below, the methods, conditions, parameters, and / or processing steps described above may, in some embodiments, be applied to the substituted LRMO materials described herein.

[0058] In one embodiment, the cathode electrode (i.e., positive electrode) includes an LRMO active material comprising a powder embedded in a binder. The powder may have an average particle / agglomerate size of 0.1 μm or more and 10 μm or less, and an average crystallite (i.e., crystallite) size of 25 nm or more and 500 nm or less. The powder (e.g., embedded in the binder) may include particles having an average maximum cross-sectional dimension of 0.1 μm or more, 0.2 μm or more, 0.5 μm or more, 1 μm or more, or larger. The powder (e.g., embedded in the binder) may include particles having an average maximum cross-sectional dimension of 10 μm or less, 5 μm or less, 2 μm or less, or smaller. Combinations of these ranges (e.g., 0.1 μm or more and 10 μm or less) are also possible. Other ranges are also possible. The powder may have crystallites (e.g., crystallites) having an average maximum cross-sectional dimension of 25 nm or more, 50 nm or more, 100 nm or more, 150 nm or more, or larger. The powder may have crystallites (e.g., crystallites) with an average maximum cross-sectional dimension of 500 nm or less, 300 nm or less, 200 nm or less, or smaller. Combinations of these ranges (e.g., 25 nm or more, 500 nm or less) are also possible. Other ranges are also possible. In one embodiment, the particles of the LRMO active material powder may have at least one of a spinel surface layer, a carbon coating (e.g., from a carbohydrate additive in the quench bath), and / or a passivating oxygen bond on the surface (e.g., from an acid additive in the quench bath). The cathode electrode may be included in a battery (e.g., a lithium-ion battery) further including an anode electrode (i.e., negative electrode), an electrolyte, and a separator.

[0059] Replacement LRMO material In one aspect, substituted lithium-rich metal oxide (S-LRMO) materials are provided in which at least a portion of the lithium has been substituted with sodium, potassium, calcium, and / or magnesium. According to various embodiments, the cathode active material comprises a substituted lithium-rich metal oxide (S-LRMO) material in which at least a portion of the lithium has been substituted with sodium, potassium, calcium, and / or magnesium. As used herein, S-LRMO materials may also be referred to as substituted alkali / alkali atom-rich metal oxide (ARMO) materials. S-LRMO materials have the following general formula: Li x A y M z ]O b (wherein A is at least one alkaline earth element and / or alkali element other than lithium, (x+y) is greater than 0 and less than 0.3, y>0.05, z=1-(x+y), M includes manganese (Mn) and nickel (Ni), and b is greater than or equal to 1.8 and less than or equal to 2.2 depending on the net oxidation state of M) may have:

[0060] In some embodiments, A is an alkaline earth element such as beryllium, magnesium, calcium, strontium, barium, and radium. In some embodiments, A is an alkali element other than lithium, such as sodium, potassium, rubidium, cesium, and francium. In one set of exemplary embodiments, A is selected from the group consisting of Na, K, Ca, and / or Mg.

[0061] In some embodiments, the S-LRMO material has the following general formula: Li x A y M z ]O b (wherein A is at least one alkali element such as Na, K, Ca and / or Mg and / or an alkali element other than lithium; (x+y) is greater than or equal to 0 and less than or equal to 0.3, y>0.05, z=1-(x+y), M is a combination of transition metals, including at least manganese (Mn) and nickel (Ni), and b is greater than or equal to 1.8 and less than or equal to 2.2 depending on the net oxidation state of M) Preferably, b=2. In one embodiment, (x+y) is greater than 0.1 and less than 0.25, e.g., 0.2, and y is greater than or equal to 0.05 and less than or equal to 0.15, e.g., greater than or equal to 0.06 and less than or equal to 0.14. In one embodiment, the material exhibits the crystallinity and phase content typically found in lithium-rich layered metal oxides (i.e., embodiments of unsubstituted LRMO materials) without evidence of other crystalline phases. In one embodiment, the S-LRMO material may have a distinct hexagonal (e.g., rhombohedral) and monoclinic phases in its initial state (e.g., before being charged for the first time). In some embodiments, these two phases may be arranged in a stacked structure. Those skilled in the art will understand, based on the teachings herein, that the stoichiometry "O2" in the chemical formula of LRMO and / or S-LRMO is not intended to be limiting to the exact stoichiometry, and that the actual elemental amount of oxygen may vary slightly (e.g., 1.9 moles or more and 2.1 moles or less of oxygen per mole of active material). This is, for example, to accommodate slight variations in the average transition metal oxidation state of other components of the material (e.g., the oxidation state of the transition metal). For example, M may include 50-80 atomic % Mn, 20-50 atomic % Ni, and 0 to 10 atomic % of other elements (e.g., Ti, Al, Fe, Co, or any combination thereof). In various embodiments, up to 20% of the lithium content in the material may be substituted with one or more alkali elements other than lithium and / or one or more alkaline earth elements. For example, 0.5% or more, 1% or more, 2% or more, 5% or more, 10% or more, or more of the lithium may be substituted with at least one of Na, K, Mg, and Ca. In some embodiments, up to 13%, up to 15%, up to 20%, or more of the lithium may be substituted with at least one of Na, K, Mg, and Ca. For example, 0.5% to 20%, e.g., 1% to 15%, or 2% to 13%, of the lithium may be substituted with at least one of Na, K, Mg, and Ca. Thus, the atomic ratio of A to lithium in the above formula may be 0.5:95.5 or more and 20:80 or less.In other words, the ratio of A to (1 + x) in the above formula can be 0.5:95.5 or greater and 20 or less. Other ranges are possible. When heat-treated as described above (e.g., sintered and rapidly cooled), S-LRMO has a classic lithium-rich crystal structure with no apparent secondary phases and exhibits some combination of trigonal (R-3m) and monoclinic (C2 / m) crystal structure features. In other words, S-LRMO contains both hexagonal and monoclinic phases, with the trigonal system being a member of the hexagonal crystal family (i.e., genus).

[0062] In some embodiments, 0.5% or more, 1% or more, 2% or more, 5% or more, 10% or more, or more of the lithium is substituted with Na. In some embodiments, 13% or less, 15% or less, 20% or less, or more, of the lithium is substituted with Na. For example, 0.5% or more and 20% or less, e.g., 1% or more and 15% or more, or 2% or more and 13% or less of the lithium may be substituted with Na. Other ranges are possible.

[0063] In some embodiments, 0.5% or more, 1% or more, 2% or more, 5% or more, 10% or more, or more of the lithium is substituted with K. In some embodiments, 13% or less, 15% or less, 20% or less, or more of the lithium is substituted with K. For example, 0.5% or more and 20% or less, e.g., 1% or more and 15% or more, or 2% or more and 13% or less of the lithium may be substituted with K. Other ranges are possible.

[0064] In some embodiments, 0.5% or more, 1% or more, 2% or more, 5% or more, 10% or more, or more of the lithium is substituted with Mg. In some embodiments, 13% or less, 15% or less, 20% or less, or more of the lithium is substituted with Mg. For example, 0.5% or more, 20% or less, e.g., 1% or more, 15% or less, or 2% or more, 13% or less of the lithium may be substituted with Mg. Other ranges are possible.

[0065] In some embodiments, 0.5% or more, 1% or more, 2% or more, 5% or more, 10% or more, or more of the lithium is substituted with Ca. In some embodiments, 13% or less, 15% or less, 20% or less, or more of the lithium is substituted with Ca. For example, 0.5% or more, 20% or less, e.g., 1% or more, 15% or less, or 2% or more, 13% or less of the lithium may be substituted with Ca. Other ranges are possible.

[0066] In some embodiments, the S-LRMO material (e.g., as a cathode active material) has the following formula: Li e A f M g ]O h (wherein e is 0.06 or less, f is 0.14 or greater, g=1-(e+f), A includes at least one of Na, K, Ca, or Mg; M includes Mn and Ni, and h is greater than or equal to 1.8 and less than or equal to 2.2) Other ranges are possible.

[0067] In some embodiments, cobalt is absent or present in relatively small amounts in the S-LRMO material. For example, in some embodiments, the atomic percentage of cobalt in the S-LRMO is zero or is 10 at% or less, 5 at% or less, 2 at% or less, 1 at% or less, 0.5 at% or less, 0.2 at% or less, 0.1 at% or less, 0.05 at% or less, 0.02 at% or less, 0.01 at% or less, 0.005 at% or less, 0.002 at% or less, 0.001 at% or less, or less. Other ranges are possible.

[0068] In some embodiments, the S-LRMO (e.g., as a cathode active material) has the formula: Li 1.14 Na 0.06 Mn 0.6 Ni 0.2In some embodiments, the S-LRMO (e.g., as a cathode active material) has the formula: Li 1.06 Na 0.14 Mn 0.6 Ni 0.2 In some embodiments, the S-LRMO (e.g., as a cathode active material) has the formula: Li 1.015 Na 0.155 Mn 0.58 Ni 0.25 In some embodiments, the S-LRMO (e.g., as a cathode active material) has the formula: Li 1.013 Na 0.157 Mn 0.52 Ni 0.32 In some embodiments, the S-LRMO (e.g., as a cathode active material) has the formula: Li 1.06 K 0.14 Mn 0.6 Ni 0.2O2. S-LRMO materials may be formed using methods similar to those described above for LRMO materials. For example, S-LRMO materials may be manufactured using precursor materials formed by sol-gel, solid-state, or co-precipitation processes. The precursor materials may include metal organic precursors of Li, Na, K, Ca, Mg, and one or more transition metals and / or Al. For example, the metal organic precursors may be selected from acetates, carbonates, nitrates, sulfates, and / or hydroxides of Li, Na, K, Ca, Mg, Mn, Ni, and optionally Fe, Co, Al, and / or Ti. In some embodiments, the precursor may include metal organic precursors of Li, Na, and / or K in excess of 0.01 mole fraction or more and 0.20 mole fraction or less. In some embodiments, the precursor may include metal organic precursors of Li and / or Na in excess of 0.01 mole fraction or more and 0.20 mole fraction or less. For example, the sol-gel may include a metal organic precursor of Li and / or Na in an excess amount of 0.01 to 0.20 mole fraction. In some embodiments, the precursor may include a metal hydroxide precursor of Li and / or Na in an excess amount of 0.01 to 0.20 mole fraction. For example, the sol-gel may include a metal hydroxide precursor of Li and / or Na in an excess amount of 0.01 to 0.20 mole fraction. Other ranges are possible. The precursors may be mixed (e.g., with a solution including water) to form a mixture. The mixture of precursors may be heated to form a gel.

[0069] The precursor (e.g., as a mixture such as a gel) may be pyrolyzed (e.g., to form an LRMO material). The precursor may be calcined at a temperature of at least 250°C and not more than 600°C, e.g., at least 300°C and not more than 500°C, for a time period of at least 2 hours and not more than 8 hours, e.g., at least 4 hours and not more than 6 hours, to pyrolyze the precursor and form an S-LRMO material. In some embodiments, the precursor may be pyrolyzed using microwave heating as described above. The decomposed precursor material may then be sintered at a sintering temperature (e.g., to form a sintered S-LRMO material). The decomposed precursor material may then be sintered at a temperature of at least 800°C, e.g., at least 850°C and not more than 1000°C, or at least 900°C and not more than 950°C, for a time period of at least 8 hours and not more than 14 hours, e.g., at least 9 hours and not more than 12 hours, or at least 10 hours and not more than 11 hours, to form the S-LRMO material. Other ranges are possible.

[0070] In some embodiments, the S-LRMO material is sintered at a sintering temperature. Sintering temperature can refer to the temperature of the environment in which the S-LRMO resides during sintering (e.g., furnace temperature). In some embodiments, the sintering temperature is 800°C or higher, 825°C or higher, 850°C or higher, 875°C or higher, 900°C or higher, or higher. In some embodiments, the sintering temperature is 1000°C or lower, 950°C or lower, 925°C or lower, or lower. Combinations of these values ​​are possible (e.g., 800°C or higher and 1000°C or lower, 850°C or higher and 950°C or lower, 900°C or higher and 950°C or lower). Other ranges are also possible.

[0071] In some embodiments, an excess of alkali metal and / or alkaline earth metal species is present in the precursor mixture, such that during heat treatment not all of the Li, Na, K and / or Mg species become part of the formed active material, but instead form residues in the powder in the form of oxides or oxyhydroxides.

[0072] The S-LRMO material may be ultra-rapidly cooled in a quenching fluid or bath from a quenching temperature to room temperature, as described above, to form the S-LRMO active material. For example, the S-LRMO material may be quenched from a sintering temperature of at least 800°C, e.g., from 800°C or more to 1000°C or less, or from 850°C or more to 950°C or less, to room temperature (e.g., 25°C) in a time period of 500 milliseconds or less, or 200 milliseconds or less, e.g., from 100 milliseconds or more to 500 milliseconds or less, or from 200 milliseconds or more to 100 milliseconds or less. Other ranges are possible. In some embodiments, the quenching temperature and the sintering temperature may be the same or substantially the same temperature.

[0073] In some embodiments, the S-LRMO material is quenched from a sintering temperature (e.g., at least 800°C, e.g., a temperature of 800°C or more and 1000°C or less, or 850°C or more and 950°C or less) to a quenching temperature in a range of 10°C or more, 15°C or more, 20°C or more, and / or 120°C or less, 100°C or less, 80°C or less, 60°C or less, 50°C or less, 45°C or less, 40°C or less, 35°C or less, 30°C or less, 25°C or less. In some embodiments, the quenching temperature is room temperature (e.g., 25°C). Quenching may occur for 500 milliseconds or less, 400 milliseconds or less, 300 milliseconds or less, less than 200 milliseconds, and / or up to 150 milliseconds, up to 100 milliseconds, or less. Combinations of these ranges are possible (e.g., quenching for times of 100 milliseconds or more, 500 milliseconds or less, or 100 milliseconds or more and 200 milliseconds or less). Other ranges are also possible.

[0074] In some embodiments, quenching (e.g., quenching within the above-mentioned time ranges) comprises allowing at least 25 wt%, at least 50 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 98 wt%, at least 99 wt%, at least 99.9 wt%, or more (e.g., 100 wt%) of the sintered S-LRMO to reach thermal equilibrium with its surrounding medium (e.g., a quench bath) at a temperature in the range of 10°C or more, 15°C or more, 20°C or more, and / or 120°C or less, 100°C or less, 80°C or less, 60°C or less, 50°C or less, 45°C or less, 40°C or less, 35°C or less, 30°C or less, 25°C or less, or less (e.g., room temperature, e.g., 25°C). In some embodiments, quenching comprises allowing at least 25%, at least 50%, at least 80%, at least 90%, at least 95%, at least 98%, at least 99%, at least 99.9%, or more (e.g., 100%) by volume of the sintered S-LRMO to reach thermal equilibrium with its surrounding medium (e.g., a quench bath) at a temperature within a range of 10° C. or more, 15° C. or more, 20° C. or more, and / or 120° C. or less, 100° C. or less, 80° C. or less, 60° C. or less, 50° C. or less, 45° C. or less, 40° C. or less, 35° C. or less, 30° C. or less, 25° C. or less, or less (e.g., room temperature, e.g., 25° C.). Other ranges are possible.

[0075] The quenching fluid may include oil, alcohol, or water, and may optionally include additives. For example, the quenching fluid may be an oil bath, an alcohol bath, or a water bath. The quenching fluid may also be referred to as a quenching bath. The quenching fluid or bath may include 50% or more, 80% or more, 90% or more, 95% or more, 98% or more, 99% or more, or more (e.g., 100% by weight) of water. Other ranges are possible. The quenching fluid or bath may include at least one acid or at least one carbohydrate (e.g., urea or sugar), or a combination thereof. In some embodiments, the quenching fluid or bath is basic in pH (e.g., pH greater than 7, 8 or more, 9 or more, 10 or more, 11 or more, 12 or more, 14 or more, or more). In some embodiments, the quenching fluid or bath may include a base, such as LiOH, NaOH, and / or KOH, as an additive.

[0076] In some embodiments, sintering may be performed in a furnace, such as a rotary furnace. The S-LRMO material may be transferred from the furnace to a quenching fluid in, for example, 500 milliseconds or less, such as 200 milliseconds or less, or even less. In some embodiments, the time between removing the sintered S-LRMO material from the furnace and quenching (e.g., by transfer to a quench bath) may be 500 milliseconds or less, 200 milliseconds or less, and / or as little as 100 milliseconds. Other ranges are possible.

[0077] The excess alkali metal and / or alkaline earth metal and Ni and Mn atoms may be uniformly and homogeneously distributed throughout the transition metal crystal lattice sites in the S-LRMO material, such that no crystalline volume in the material is larger than 3×3×3 nm in which the ratio of Ni, Mn, A (where A is at least one of Na, K, Ca, or Mg), and Li atoms differs by more than 3% compared to the average ratio of Ni, Mn, Na, K, Ca, Mg, and Li atoms in the bulk material.

[0078] According to various embodiments, S-LRMO materials utilize less Li by substituting cheaper elements for Li. Therefore, S-LRMO materials have reduced material costs compared to unsubstituted LRMO materials. Furthermore, S-LRMO materials also offer unexpected capacity stability, rate capability, and unexpectedly high voltage compared to conventional unsubstituted LRMO materials. Additionally, in the context of the present disclosure, it has been unexpectedly observed that relatively high amounts of lithium in LRMO materials can be substituted with different cations (e.g., alkali metals and / or alkaline earth metals, such as sodium, potassium, magnesium, and / or calcium) to form S-LRMOs while maintaining substantially the same crystal structure and properties as the unsubstituted analogs. For example, it was surprising that relatively high levels of lithium substitution (e.g., greater than 5% to 20%) could be achieved substantially without potentially deleterious phenomena, such as the formation of second crystalline phases. This contrasts with expectations from the literature, which has shown that in the case of lithium metal oxide electrode active materials containing Ni and Mn, substituting Na for some Li results in the formation of a second crystalline phase (Na 0.7 It has been reported that the effect of Sodium additive to improve the rate performance of Li [Li 0.2 Mn 0.54 Ni 0.13 Co 0.13 ]O2 material for Li-ion batteries.” Journal of Power Sources, 244, 29-34.) Substantial occurrence of such secondary phases has not been observed in the materials of the present disclosure. Without wishing to be bound by any particular theory, it is believed that one factor in the observation of high levels of lithium substitution without destroying the desired crystallinity and / or electrochemical properties is the use of the techniques of the present disclosure (e.g., rapid cooling in water, etc.).

[0079] In one embodiment, a method for forming an active material for a positive electrode of a lithium-ion battery includes quenching a powder of active material in water. In one embodiment, the method further includes calcining the active material powder prior to quenching. The active material may be calcined at a temperature of at least 800°C. The water may be at room temperature before quenching, and the active material powder may be quenched at a rate of at least 1750°C / second.

[0080] In one embodiment, the active material comprises a layered substituted lithium-rich nickel manganese oxide. The excess Li, Ni, and Mn atoms may be uniformly and evenly distributed throughout the transition metal crystal lattice sites, such that no crystalline volume larger than 3 × 3 × 3 nm exists in the material where the ratio of Ni, Mn, and Li atoms differs by more than 3% compared to the average ratio of Ni, Mn, and Li atoms in the bulk material. The particles of the active material powder may be in the form of aggregates having an average size of 0.1 μm to 20 μm, and the aggregates of the active material powder are composed of crystallites having an average size of 25 nm to 500 nm. After quenching, the active material powder may comprise a composite of hexagonal and monoclinic phases, a combination of LiAMO2(R-3m) phase and (LiA)2MnO3(C2 / m) phase, where M is at least one of Ni or Mn, and A is a combination of non-lithium alkali metals and alkaline earth metals. The active material powder may comprise a solid solution whose crystal structure has predominantly or entirely C2 / m symmetry.The active material powder may comprise a solid solution whose crystal structure has predominantly or entirely R-3m symmetry.

[0081] In one embodiment, the quench water includes an additive solvated therein. The water may include an additive at a concentration of 0.01 moles / liter or more and 1.0 moles / liter or less. In one embodiment, the additive includes an acid, which may be selected from sulfuric acid, citric acid, acetic acid, phosphoric acid, hydrochloric acid, ammonium phosphate, or a combination thereof. In another embodiment, the additive includes a carbohydrate, which may be selected from fructose, galactose, glucose, lactose, maltose, sucrose, or a combination thereof.

[0082] In one embodiment, the active material is disposed in a positive electrode of a lithium-ion battery cell further comprising a negative electrode and an electrolyte. In this context, the positive electrode corresponds to the cathode and the negative electrode corresponds to the anode. The active material comprises a hexagonal phase and a monoclinic phase prior to electrochemical cycling of the battery, and after electrochemical cycling, the active material powder is free of the monoclinic phase.

[0083] In one embodiment, the positive electrode material in the battery cell has a specific capacity of at least 230 mAh / g (at a charge rate of C / 20) after 50 electrochemical cycles at a discharge rate of up to C / 2.

[0084] In one embodiment, a lithium-ion battery cell includes a negative electrode, an electrolyte, and a positive electrode including a layered lithium-rich nickel manganese oxide active material, and the battery cell has a specific capacity of at least 215 mAh / g (at a C / 20 rate) after 50 electrochemical cycles at a discharge rate up to C / 2.

[0085] In one embodiment, the active material powder particles are in the form of aggregates having an average size of 0.1 μm or more and 10 μm or less, and the active material powder aggregates are composed of crystallites having an average crystal size of 25 nm or more and 500 nm or less. The active material powder particles may have at least one of a spinel surface layer, a carbon coating, or passivated oxygen bonds on the surface.

[0086] In some embodiments, less than 10% (e.g., less than 5%, less than 2%, less than 1%, less than 0.1%, or even less) of the non-overlapping crystalline volume of the material greater than 3x3x3 nm has a ratio of Ni, Mn, and alkali metal and / or alkaline earth metal atoms that differs by more than 3% compared to the average ratio of Ni, Mn, Li, and alkali metal and / or alkaline earth metal atoms in the bulk material. Such spatial distribution may be due to a high degree of cation disorder (e.g., due to a uniform distribution of Li, K, Na, Ca, Mg, Ni, and / or Mn atoms). Other ranges are possible.

[0087] In some embodiments, there are no crystalline volumes in the material larger than 3x3x3 nm in which the ratio of Ni, Mn, and alkali metal and / or alkaline earth metal atoms differs by more than 3% compared to the average ratio of Ni, Mn, Li, and alkali metal and / or alkaline earth metal atoms in the bulk material. Such spatial distribution may be due to a high degree of cation disorder (e.g., due to a uniform distribution of Li, K, Na, Ca, Mg, Ni, and / or Mn atoms).

[0088] In one embodiment, the included excess Li, K, Na, Ca, Mg, Ni and / or Mn atoms are homogeneously and uniformly distributed throughout the transition metal crystal lattice sites, such that there are no crystalline volumes in the material larger than 3x3x3 nm in which the ratio of Ni, Mn and alkali metal and / or alkaline earth metal atoms differs by more than 3% compared to the average ratio of Ni, Mn and Li atoms in the bulk material.

[0089] Example The following examples are intended to illustrate certain embodiments of the present invention, but do not exemplify the full scope of the invention.

[0090] Experimental Example Based on the example, the formula: Li x (Mn y Ni 1-y ) 2-xUnsubstituted LRMO powder of O2 (x = 1.16, y = 0.7) was prepared using the following method. Specifically, a precursor material gel was generated using a sol-gel solid-state synthesis method. The synthesis of the sol involved forming an aqueous mixture containing stoichiometric amounts of Li(CH3COO) 2H2O, Mn(CH3COO)2 4H2O, and Ni(NO3)2 6H2O. The mixture was heated at 100 °C until a gel was formed. The gel was poured into an alumina crucible and then calcined at 400 °C for 90 min to obtain an organic-free ash. The resulting ash was crushed and re-calcined in the crucible at 500 °C for 3 h, then naturally cooled and re-ground. The powder was then sintered at 900 °C for 24 h and then quenched. All sintering was performed in a box furnace under fume hood conditions. All quenching was performed after heating at 900 °C for 12–24 h.

[0091] Figure 1 is a photograph of a rapid cooling system 100 according to various embodiments of the present disclosure. Figure 2 includes four sequential video capture time-lapse images taken at 30 frames per second illustrating the rapid cooling process according to various embodiments of the present disclosure.

[0092] 1 and 2, the LRMO material was fed into a tube furnace 110, where it was heated to 900°C. The heated LRMO material was discharged from the tube furnace 110 and quenched to room temperature in a quench bath 120. The tube furnace 110 rotates during operation, and its contents are rapidly quenched into the quench bath 120. The LRMO material was discharged from the furnace 110 at 900°C and quenched to room temperature in less than 500 milliseconds, e.g., less than 200 milliseconds, to form the LRMO active material. After quenching, the LRMO material was filtered from the water in the quench bath 120 and dried in a vacuum oven.

[0093] In the first comparative example, the LRMO material was sintered at 900°C and then slowly cooled in the furnace 110. In the second comparative example, the LRMO material was sintered and then dropped onto a metal plate to cool. In the third comparative example, the LRMO material was first slowly cooled to room temperature and then inserted into the tubular furnace 110 for the ultra-rapid cooling process, which was held at 900°C for 30 to 120 minutes before the ultra-rapid cooling process.

[0094] In the first example, a portion of the Li content was replaced with Na to produce a Na-substituted LRMO material. The same recipe as above was used, but 5% of the Li content was replaced with Na, resulting in a final nominal chemical formula of Li[Li 0.14 Na 0.06 Mn 0.6 Ni 0.2 ]O2.

[0095] In a second example, a portion of the Li was replaced with Na to produce a Na-substituted LRMO material. A stoichiometric amount of MnNi-OH precursor was mixed with appropriate amounts of Li2CO3 and Na2CO3, resulting in 12.5% ​​of the Li content being replaced with Na. The resulting nominal chemical formula was Li[Li 0.06 Na 0.14 Mn 0.6 Ni 0.2 ]O2 and the material was heat treated as described above.

[0096] In a third example, a portion of the Li was replaced with K to produce a K-substituted LRMO material. A stoichiometric amount of MnNi-OH precursor was mixed with appropriate amounts of Li2CO3 and K2CO3, resulting in 12.5% ​​of the Li content being replaced with K. The resulting nominal chemical formula was Li[Li 0.06 K 0.14 Mn 0.6 Ni 0.2 ]O2 and the material was heat treated as described above.

[0097] In the fourth example, a K·Na-substituted LRMO material was fabricated by substituting a portion of the Li with K and Na. A stoichiometric amount of MnNi-OH precursor was mixed with appropriate amounts of Li2CO3, K2CO3, and Na2CO3, and 12.5% ​​of the Li content was substituted with equal amounts of Na and K. The resulting nominal chemical formula was Li[Li 0.06 K 0.07 Na 0.07 Mn 0.6 Ni 0.2 ]O2 and the material was heat treated as described above.

[0098] Materials characterization Figures 3 and 4 are graphs of X-ray diffraction (XRD) patterns of LRMO materials according to comparative and non-comparative embodiments of the present disclosure. The XRD pattern in Figure 3 was generated from a layered LRMO active material that was not rapidly quenched by immersion in water, and the XRD pattern in Figure 4 was generated from a layered LRMO active material that was rapidly quenched by immersion in water.

[0099] Evaluation of the XRD patterns indicates that the LRMO material has the expected hexagonal (e.g., rhombohedral) phase, LiNiO2-related space group (R-3m), and monoclinic phase, Li2NiO3-related space group (C2 / c).

[0100] FIG. 5 shows Li sol-gel precursor material treated with microwave heating for 5 minutes prior to the high-temperature calcination step, according to various embodiments of the present disclosure. x (Mn y Ni 1-y ) 2-x 5 is a graph showing the X-ray diffraction results for the LiNiO2 material (x=1.16, y=0.7). Referring to FIG. 5, it is important to note that the X-ray diffraction pattern of this microwave-digested material is consistent with that of a highly crystallized and optimized material, containing the rhombohedral phase LiNiO2-related space group (R-3m) and the monoclinic phase Li2NiO3-related space group (C2 / c). Therefore, this material is suitable for forming LRMO using annealing at 900°C and rapid and / or ultra-rapid cooling, as described above.

[0101] FIG. 6 shows Li processed using microwave heating and ultra-rapid cooling according to various embodiments of the present disclosure. x (Mn y Ni 1-y ) 2-x 6 is a graph showing the X-ray diffraction results for O2 material (x=1.16, y=0.7). Referring to FIG. 6, all expected peaks are present and clear.

[0102] Figure 7A shows an example of prior art, as described in the literature (H. Zheng, et al., "Recent developments and challenges of Li-rich Mn-based cathode materials for high-energy lithium-ion batteries," Materials Energy Today, Volume 18, December 2020, Page 100518), showing high-angle annular dark-field (HAADF) atomic map micrographs of a typical LRMO material that was not subjected to rapid cooling before electrochemical cycling. As is evident from these micrographs, the initial LRMO material had significant nickel and manganese segregation within the grains.

[0103] 7B shows TEM HAADF atomic map micrographs of the resulting unsubstituted LRMO material, which was subjected to rapid cooling before electrochemical cycling, according to various embodiments of the present disclosure. As is evident from these micrographs, the LRMO material did not have significant nickel / manganese segregation within the particles. Thus, rapid or ultra-rapid cooling reduces or eliminates nickel segregation to the particle surface, and nickel and manganese are uniformly mixed throughout the bulk of the LRMO material.

[0104] FIG. 8A is a graph showing cell potential vs. specific capacity, and FIG. 8B is a graph showing Li x (Mn y Ni 1-y ) 2-x 1 is a graph of specific capacity vs. cycles for an example of an O2 material (x=1.16, y=0.7), where the material was not microwaved or rapidly cooled (in this case, cooled relatively slowly on a metal plate).

[0105] FIG. 9A is a graph showing cell potential vs. specific capacity during the break-in cycle, FIG. 9B is a graph showing cell potential vs. specific capacity over time, FIG. 9C is a graph showing specific capacity vs. cycles at a C / 20 rate, and FIG. 9D is a graph showing discharge specific capacity vs. cycle number at a C / 5 rate (reference cycle at C / 20) for a cell including an unsubstituted LRMO active material according to a comparative embodiment of the present disclosure.

[0106] Crystalline uniformity, cationic disorder and surface passivation One way to assess the degree of metal cation disorder in a material is to use the ratio of peak intensities in the X-ray diffraction pattern. Specifically, the ratio of the intensity of the (003) peak to the intensity of the (104) peak is generally known as a rough indicator of electrochemical activity in such mixed-cation materials with a predominantly layered crystal structure, while the ratio of the sum of the intensities of the (006) and (102) peaks to the intensity of the (101) peak is an indicator of cation disorder. Based on this, materials treated with microwaves during the decomposition step and then ultra-rapidly cooled exhibit a significantly higher indicator of electrochemical activity and a lower degree of cation order (and therefore higher cation disorder) compared to slowly cooled materials.

[0107] [Table 2]

[0108] Table 2 shows the XRD peak intensity ratios for a first comparative LRMO material that was sintered and then slowly cooled (row 1), and a second unsubstituted LRMO material and an exemplary S-LRMO material that were formed using an ultra-rapid cooling process after sintering (rows 2 and 3, respectively). The unsubstituted LRMO material has the formula: Li[Li x (Mn y Ni 1-y ) 1-x]O2 (x=0.2, y=0.75). Importantly, the exemplary ultra-rapidly cooled material exhibits XRD characteristics indicative of increased atomic disorder in the material. Specifically, the exemplary material exhibits a 9% increase in the ratio of the sum of the intensities of the (006) and (102) peaks to the intensity of the (101) peak. This significant increase in cation disorder represents a situation in which Ni and Mn atoms are more thoroughly mixed (and therefore less grouped) in the material and coexist with Li and substitutional elements in the transition metal sites. These data demonstrate that different states of matter can be produced based on the processing conditions used, particularly the cooling rate, and have also been observed in S-LRMO materials.

[0109] 10-13 are charts showing X-ray diffraction pattern results for S-LRMO materials containing various amounts of Na and / or K, as described in the previous section, according to various embodiments of the present disclosure. The S-LRMO materials were prepared using the heat treatment and ultra-rapid cooling process described above. As shown in FIGS. 10-13, the S-LRMO materials possessed typical phase purity of LRMO materials. The XRD data is also consistent with the material exhibiting high cation mixing / disorder at the transition metal sites in the material.

[0110] 15-22 are graphs illustrating the electrochemical performance of lithium-ion cells formed using various identified S-LRMO materials. In particular, FIGS. 15 and 16 respectively illustrate the electrochemical performance of S-LRMO materials with the chemical formula Li[Li 0.14 Na 0.06 Mn 0.6 Ni 0.2 17 is a graph of voltage vs. specific capacity for the first 2 cycles and cycles 13-26 for a cell in which the chemical formula of the S-LRMO material is Li[Li 0.14 Na 0.06 Mn 0.6 Ni 0.2]O2, with the inset being a graph of voltage vs. specific capacity. FIG. 18 is a plot of charge and discharge specific capacity (i.e., voltage vs. specific capacity) for a cell containing an S-LRMO material in which Na has substituted 12.5% ​​lithium. FIG. 19 is a plot of cycle number vs. charge / discharge efficiency and discharge specific capacity over 100 cycles for a cell containing an S-LRMO active material. FIGS. 20A-20B are graphs of discharge specific capacity vs. cycle number (i.e., cycling stability) (FIG. 20A) and voltage vs. specific capacity (FIG. 20B) for a cell containing an S-LRMO material. The chemical formula of the S-LRMO material in FIGS. 18-20 is Li[Li 0.06 Na 0.14 Mn 0.6 Ni 0.2 21 and 22 show that the S-LRMO material has the formula: Li[Li 0.06 K 0.14 Mn 0.6 Ni 0.2 ]O2 and chemical formula: Li[Li 0.06 Na 0.07 K 0.07 Mn 0.6 Ni 0.2 ]O2 for the first two cycles of the cell.

[0111] As shown in Figures 15-22, in contrast to the rapid capacity and voltage degradation of conventional lithium-rich materials, the S-LRMO active material had excellent performance and stability with little or no capacity degradation over many cycles.

[0112] Figure 23 shows the relationship between Li[Li 0.06 K 0.14 Mn 0.6 Ni 0.223 is a graph of voltage vs. specific capacity showing discharge rate data for the ]O2 material. As shown in Figure 23, this material has high rate capability, with a capacity of approximately 180 mAh / g at a C / 2 rate. This superior rate capability is believed to be due to the alkali atoms in the crystalline material creating easier lithium ion transport pathways within the system, thereby enabling electrical conductivity and rate capability.

[0113] Figure 24 shows the material: Li[Li 0.015 Na 0.155 Mn 0.58 Ni 0.25 1 is a chart showing data for the first two charge-discharge cycles of a lithium metal half-cell made with ]O2, showing a specific capacity of over 250 mAh / g at a C / 20 rate.

[0114] Figure 25 shows the material: Li[Li 0.015 Na 0.155 Mn 0.58 Ni 0.25 1 is a chart showing cycle life data for a lithium metal anode half-cell fabricated with ]O2, showing stable capacity retention well above 200 mAh / g and repeated reference cycling. The mid-discharge voltage is also nominally stable, which is not typical for lithium-rich cathode materials.

[0115] In particular, the S-LRMO active material exhibited stable capacity and voltage profiles, a significant improvement over conventional LRMO materials of similar composition that were not substituted or heat-treated (e.g., not rapidly cooled) as described above. Cells containing the S-LRMO active material exhibited specific capacities exceeding 260 mAh / g at a C / 20 rate, e.g., 265-275 mAh / g. As shown in Figure 16, Li 1.14 Na 0.06 Mn 0.6 Ni 0.2Cells containing the O2 active material have demonstrated stable discharge specific capacity and charge / discharge efficiency over tens of cycles, demonstrating excellent stability and cycle life. Thus, the S-LRMO active material exhibits less than 10% (e.g., less than 5%, less than 2%, or less) loss in average discharge voltage at a C / 20 rate after 200 charge / discharge cycles of a lithium-ion battery, and / or less than 5% (e.g., less than 3%, less than 2%, or less) capacity degradation over 200 C / 4 charge / discharge cycles of a lithium-ion battery, and / or greater than 200 mAh / g specific capacity (e.g., greater than 230 mAh / g, greater than 250 mAh / g, or more) when charged / discharged at a C / 20 rate, and / or a C / 2 discharge specific capacity that is at least 75% (e.g., at least 80%, 85%, 90%, or more) of the C / 20 discharge specific capacity. In some embodiments, the S-LRMO active material has a full cycle discharge voltage of 3.5 V or greater (e.g., 3.8 V or greater, 4.0 V or greater, or greater) at a C / 20 rate after 200 cycles. In some embodiments, the S-LRMO active material has a full cycle discharge voltage of 10.0 V or less (e.g., 8.0 V or less, 6.0 V or less, or 5.0 V or less) at a C / 20 rate after 200 cycles. Combinations of the above ranges are also possible (e.g., 3.5 V or greater and 10.0 V or less after 200 cycles).

[0116] In some embodiments, an S-LRMO active material (e.g., as a cathode active material) exhibits a Li diffusivity value (diffusion coefficient) at or below 30% state of charge (e.g., at a temperature of 298 K) that is at least one-third of an order of magnitude (e.g., at least one-half order of magnitude or more, at least one order of magnitude or more, and / or up to 1.5 orders of magnitude, up to two orders of magnitude, or up to more) greater than an otherwise identical unsubstituted LRMO, which may have the same stoichiometry as S-LRMO, except that all species (e.g., Na, K, Mg, Ca) that substitute for lithium in S-LRMO are substituted with lithium.

[0117] In some embodiments, the S-LRMO active material (e.g., as a cathode active material) exhibits a fast pulse resistance at a state of charge of 30% or less (e.g., at a temperature of 298 K) that is lower (e.g., at least 20%, at least 30%, at least 40%, at least 50% or more lower) than an otherwise identical unsubstituted LRMO.

[0118] The X-ray data shown in Figures 10-13 indicate that high lithium substitution (e.g., at least 12.5%) can be tolerated without substantially affecting the crystalline structure of LRMO or producing secondary crystalline phases. All of these X-ray diffraction patterns show only the expected lithium-rich crystalline phase structure, regardless of the type or amount of substitution material used. TEM / EDS data shown in Figure 14 indicates that in the example material with 5% Na substitution, Mn and Ni still have a uniform spatial distribution throughout the sample.

[0119] Electrochemical Testing The synthesized cathode material was mixed with Super-P carbon black and polyvinylidene fluoride (PVDF) in a 9.2:0.4:0.4 ratio, with the active material accounting for 92% of the total mass. The resulting blend was mixed in approximately 15 mL of N-methyl-2-pyrrolidone for at least 1 hour, followed by two 10-minute sonication sessions. The resulting slurry was then further mixed on a hot plate at 100 °C for at least 30 minutes and coated onto a 50 μm-thick, 10 × 10 cm aluminum foil heated to temperatures above 100 °C. The foil was dried overnight in an oven at 70 °C in air and then punched out with a biopsy punch. These punched pieces were used to fabricate 2032 coin cells with a lithium foil anode, an electrolyte containing a carbonate mixture and LiPF salt solution, a Celgard battery separator, a 0.5 mm stainless steel spacer, and a wave spring on the cathode side to ensure mechanical contact within the cell. Each coin cell was assembled and sealed using a coin cell press under an oxygen-depleted argon atmosphere.

[0120] To examine the electrochemical performance, the coin cells fabricated by the above method were subjected to galvanostatic testing under constant current with a low-current battery tester, with the potential limited at a constant current. The cells were cycled at constant current charge and discharge rates of C / 20 to C / 2 over the range of 4.8 V to 2 V, as described above with reference to Figures 15 to 22.

[0121] 26A-26B show representative galvanostatic intermittent titration data, demonstrating that the diffusivity of Li in the replacement material is an order of magnitude higher at low states of charge. This is particularly interesting in some embodiments where the rate capability of cathode materials at low voltages is typically an issue; for example, in some cases, better diffusivity at low states of charge may be able to support higher power demands in battery cells near the end of discharge.

[0122] 27A and 27B are charts showing diffusivity data obtained from GITT (galvanostatic intermittent titration) of Li prepared as described. 1.081 Na 0.057 Mn 0.652 Ni 0.21 In some embodiments, the lithium ion transport capability of O2 is such that at low states of charge, Li 1.17 Mn 0.58 Ni 0.25 Figure 27B also shows that the Li 1.081 Na 0.057 Mn 0.652 Ni 0.21 O2 and Li 1.17 Mn 0.58 Ni 0.25 The rapid pulse resistance using the same test cell (14 mm diameter circular electrodes) with O2 is shown, and Li 1.17 Mn 0.58 Ni 0.25 The S-LRMO has a diffusivity about half an order of magnitude greater than that of the non-substituted material below 3.3 V. Furthermore, the S-LRMO has a significantly lower fast pulse resistance.

[0123] 28A to 28C show the Na-substituted S-LRMO materials (Li 1.081 Na 0.057 Mn 0.652 Ni 0.21 28A and 28B are plots showing the long-term (320 cycles) cycling stability of a 1000mAh battery (O2). Figure 28A shows the capacity stability (C / 3 daily cycles and a C / 15 reference cycle every 25 cycles), Figure 28B shows the average discharge voltage, and Figure 28C shows the coulombic efficiency.

[0124] The above description of the disclosed embodiments of the invention is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0125] While several embodiments of the present invention have been described and illustrated, those skilled in the art will readily conceive of various other means and / or structures for performing the functions described herein and / or achieving the effects described herein and / or one or more of the advantages described herein, and all such various variations and / or modifications are deemed to be within the scope of the present invention. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are exemplary, and that the actual parameters, dimensions, materials, and / or configurations will depend on the particular application in which the teachings of the present invention are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Accordingly, it should be understood that the above-described embodiments are presented by way of example only and that, within the scope of the appended claims and their equivalents, the invention may be practiced otherwise than as specifically described and claimed. The present invention is directed to each individual feature, system, article, material, and / or method described herein. Moreover, combinations of two or more of these features, systems, articles, materials, and / or methods, unless mutually inconsistent, are also within the scope of the present invention.

[0126] The phrase "at least a portion" as used in the specification and claims means "partially or entirely." "At least a portion" may mean, according to certain embodiments, at least 1%, at least 2%, at least 5%, at least 10%, at least 25%, at least 50%, at least 75%, at least 90%, at least 95%, or at least 99% by weight, and / or in certain embodiments, up to 100% by weight.

[0127] The indefinite articles "a" and "an," as used in the specification and claims, unless specifically and clearly indicated to the contrary, should be understood to mean "at least one."

[0128] The phrase "and / or," as used in the specification and claims, should be understood to mean "either or both" of the elements it associates. That is, it means that the elements are present together in some cases and separately in other cases. Unless specifically and explicitly stated to the contrary, other elements (whether related or not) other than the elements identified by the "and / or" clause may optionally be present. Thus, as a non-limiting example, a reference to "A and / or B" in combination with open-ended language such as "comprising" may mean, in one embodiment, A without B (which may optionally include other elements other than B); in another embodiment, B without A (which may optionally include other elements other than A); and in yet another embodiment, both A and B (which may optionally include other elements).

[0129] As used herein and in the claims, "or" should be understood to have the same meaning as "and / or" above. For example, when "or" or "and / or" is used to separate items in a list, it should be interpreted inclusively, i.e., to mean the inclusion of at least one of the elements or elements in the list, as well as the inclusion of more than one, and optionally additional unlisted elements. Only language clearly indicating the contrary, such as "only one of" or "exactly one of," or, when used in the claims, "consisting of," means the inclusion of exactly one of the elements or elements in the list. In general, the word "or" as used herein shall be construed to indicate exclusive alternatives (i.e., "one or the other but not both") only when preceded by terms of exclusion, such as "either," "one of," "only one of," or "exactly one of." "Consisting essentially of," when used in the claims, shall have its ordinary meaning as used in the field of patent law.

[0130] In this specification and claims, the phrase "at least one," when used in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list, and does not necessarily include at least one of every element identified in the list, nor does it exclude any combination of elements in the list. This definition also allows for the optional presence of elements (whether related or not) other than the elements identified in the list to which "at least one" refers. Thus, as a non-limiting example, a reference to "at least one of A and B" (or, equivalently, "at least one of A or B," or "at least one of A and / or B") means, in one embodiment, at least one (and optionally a plurality) of A's (which may optionally include elements other than B) without B; in another embodiment, at least one (and optionally a plurality) of B's ​​(which may optionally include elements other than A) without A; and in yet another embodiment, at least one (and optionally a plurality) of A's and at least one (and optionally a plurality) of B's ​​(which may optionally include other elements).

[0131] Concentrations and percentages set forth herein are by weight unless expressly indicated to the contrary.

[0132] As used herein, "wt%" is an abbreviation for weight percent. As used herein, "at%" is an abbreviation for atomic percent.

[0133] Some embodiments may be embodied as a method, various examples of which have been described above. Acts performed as part of a method may be in any suitable order. Thus, embodiments may include acts performed in a different order than described, may include different (e.g., more or fewer) acts than described, and / or may perform some acts simultaneously even though operations are shown to be performed sequentially in particularly described embodiments above.

[0134] The use of ordinal terms such as "first," "second," and "third" in a claim to modify a claim element does not, in itself, imply a priority, precedence, or order of the claim element relative to other claim elements, or the chronological order in which method actions are performed. They are merely used as labels to distinguish one claim element with a certain name from other elements with the same name (except for the use of the ordinal term).

[0135] In the claims, as well as in the specification above, all transitional phrases such as "comprising," "including," "carrying," "having," "containing," "involving," and "holding" are to be understood to be open-ended, i.e., meaning "including, but not limited to." Only the transitional phrases "consisting of" and "consisting essentially of" shall be construed as closed or semi-closed transitional phrases, respectively, as defined in U.S. Patent and Trademark Office Manual of Patent Examining Procedures (MPEP) 2111.03.

Claims

1. sintering the substituted lithium-rich metal oxide (S-LRMO) material at a sintering temperature to form a sintered S-LRMO material; and quenching the sintered S-LRMO material from the sintering temperature to a quench temperature of 120°C or less in less than 500 milliseconds, thereby forming a quenched S-LRMO active material. A method comprising: The quenched S-LRMO active material has the formula: L[L) ｘ A ｙ M ｚ ]O ｂ (Wherein, A contains at least one of Na, K, Ca, and Mg, (x+y) is greater than 0 and less than 0.3; y>0.05, z=1−(x+y), M includes Mn and Ni, and b is 1.8 or more and 2.2 or less The method is represented by

2. 2. The method of claim 1, wherein the quenching temperature is 10°C or higher.

3. 10. The method of claim 1, wherein the quenching temperature is room temperature.

4. The method according to any one of claims 1 to 3, wherein the sintering temperature is at least 800°C.

5. The method according to any one of claims 1 to 4, wherein the sintering temperature is 900°C or higher and 950°C or lower.

6. The method of any one of claims 1 to 5, wherein the step of quenching the sintered S-LRMO material from the sintering temperature to the quenching temperature comprises quenching from the sintering temperature to the quenching temperature in 200 milliseconds or less.

7. 7. The method of claim 1, wherein the step of quenching the sintered S-LRMO material from the sintering temperature to the quenching temperature comprises quenching from the sintering temperature to the quenching temperature in a time period of at least 100 milliseconds and not more than 200 milliseconds.

8. b=2; the atomic ratio of A to lithium is in the range of 0.5:95.5 to 20:80; and M includes 50 atomic % or more and 80 atomic % or less of Mn, 20 atomic % but 50 atomic % or less of Ni, 0 atomic % or more and 10 atomic % or less of Ti, Al, Fe, Co, or a combination thereof; The method according to any one of claims 1 to 7.

9. sintering includes sintering the S-LRMO material in a furnace; and quenching includes quenching the sintered S-LRMO material in a quench bath; The method according to any one of claims 1 to 8.

10. A method according to any one of claims 1 to 9, wherein the time between removing the sintered S-LRMO material from the furnace and quenching the sintered S-LRMO material at the temperature of the quench bath is 200 milliseconds or less.

11. The method of any one of claims 1 to 10, wherein the quenching bath comprises a water bath, an oil bath, an alcohol bath, or a water bath containing an additive comprising an acid, a carbohydrate, an alcohol, or a combination thereof.

12. 12. The method of any one of claims 1 to 11, wherein quenching comprises quenching the sintered S-LRMO material in a quench bath, the quench bath comprising a water bath, an oil bath, an alcohol bath, or a water bath containing an additive comprising an acid, a carbohydrate, an alcohol, or a combination thereof.

13. forming a mixture of water and an organometallic precursor or metal hydroxide precursor of lithium, and one or more transition metals; and heating the mixture to form a gel; pyrolyzing the gel to form an S-LRMO material; The method of any one of claims 1 to 12, further comprising:

14. 14. The method of claim 13, wherein the one or more transition metals include nickel and manganese.

15. 15. The method of claim 13 or 14, wherein pyrolyzing the gel comprises using microwave irradiation.

16. the gel comprises an excess of an organometallic precursor or metal hydroxide precursor of lithium in a mole fraction of greater than or equal to 0.01 and less than or equal to 0.20; and S-LRMO materials include inorganic materials containing lithium, sodium, nickel, manganese, and oxygen; The method according to any one of claims 13 to 15.

17. The S-LRMO material has the formula: Li １．１４ Na ０．０６ Mn ０．６ Ni ０．２ O ２ The method according to any one of claims 1 to 16, wherein

18. The S-LRMO material has the formula: Li １．０６ Na ０．１４ Mn ０．６ Ni ０．２ O ２ The method according to any one of claims 1 to 16, wherein

19. The S-LRMO material has the formula: Li １．０１５ Na ０．１５５ Mn ０．５８ Ni ０．２５ O ２ The method according to any one of claims 1 to 16, wherein

20. The S-LRMO material has the formula: Li １．０１３ Na ０．１５７ Mn ０．５２ Ni ０．３２ O ２ The method according to any one of claims 1 to 16, wherein

21. The S-LRMO material has the formula: Li １．０６ K ０．１４ Mn ０．６ Ni ０．２ O ２ The method according to any one of claims 1 to 16, wherein

22. The method of any one of claims 1 to 21, further comprising forming a cathode comprising an active S-LRMO material.

23. 23. The method of claim 22, further comprising forming a lithium ion battery comprising the cathode, the anode, and the electrolyte.

24. The method of any one of claims 1 to 16, wherein M is a transition metal.

25. The method of any preceding claim, wherein the sintered S-LRMO material and / or the quenched S-LRMO active material comprises loose powder having particles with an average maximum cross-sectional dimension of at least 0.02 microns and at most 1 micron.

26. pyrolyzing the precursor material using convection heating, microwave irradiation and / or radiant heating to form a pyrolyzed substituted lithium-rich metal oxide (S-LRMO) material; sintering the pyrolyzed S-LRMO material to form a sintered S-LRMO material; and quenching the sintered S-LRMO material to form a quenched S-LRMO material. A method comprising: Quenched S-LRMO has the formula: L[L) ｘ A ｙ M ｚ ]O ｂ (Wherein, A contains at least one of Na, K, Ca, and Mg, (x+y) is greater than 0 and less than 0.3; y>0.05, z=1−(x+y), M includes Mn and Ni, and b is 1.8 or more and 2.2 or less The method is represented by

27. 27. The method of claim 26, wherein the pyrolyzing is performed using microwave irradiation.

28. 28. The method of any one of claims 26 to 27, wherein the precursor material comprises an organometallic precursor or a metal hydroxide precursor of Li, Na, Mn and Ni selected from at least one of acetates, carbonates, nitrates, sulfates or hydroxides of Li, Na, Mn and Ni.

29. b=2; the atomic ratio of A to lithium is 0.5:95.5 to 20:80; and M includes 50 atomic % or more and 80 atomic % or less of Mn, 20 atomic % or more and 50 atomic % or less of Ni, 0 atomic % or more and 10 atomic % or less of Ti, Al, Fe, Co, or a combination thereof; The method according to any one of claims 26 to 28.

30. forming a mixture of water and at least one organometallic precursor of Li, Na, Ni, and Mn; and heating the mixture to form a gel; 30. A method according to any one of claims 26 to 29, comprising the step of pyrolysing the precursor material comprising heating the gel using microwave radiation.

31. 31. The method of claim 30, wherein the mixture comprises excess organometallic precursors of Li, Na, and K at a molar fraction of 0.01 to 0.

20.

32. 31. The method of claim 30, wherein the mixture comprises an excess of Li and at least one organometallic precursor of Na, K, Ca, or Mg in a mole fraction of 0.01 to 0.

20.

33. 33. The method of any one of claims 26 to 32, wherein quenching comprises quenching the sintered S-LRMO material from the sintering temperature to a quench temperature of 120°C or less in 500 milliseconds or less to form a quenched S-LRMO material.

34. 34. The method of claim 33, wherein quenching comprises quenching the sintered S-LRMO material from the sintering temperature to the quenching temperature in 500 milliseconds or less to form the quenched S-LRMO material.

35. The method according to any one of claims 33 to 34, wherein the quenching temperature is 10°C or higher.

36. The method of any one of claims 33 to 35, wherein the quenching temperature is room temperature.

37. The S-LRMO material has the formula Li １．１４ Na ０．０６ Mn ０．６ Ni ０．２ O ２ The method according to any one of claims 26 to 36, wherein

38. The S-LRMO material has the formula Li １．０６ Na ０．１４ Mn ０．６ Ni ０．２ O ２ The method according to any one of claims 26 to 36, wherein

39. The S-LRMO material has the formula Li １．０１５ Na ０．１５５ Mn ０．５８ Ni ０．２５ O ２ The method according to any one of claims 26 to 36, wherein

40. The S-LRMO material has the formula Li １．０１３ Na ０．１５７ Mn ０．５２ Ni ０．３２ O ２ The method according to any one of claims 26 to 36, wherein

41. The S-LRMO material has the formula Li １．０６ K ０．１４ Mn ０．６ Ni ０．２ O ２ The method according to any one of claims 26 to 36, wherein

42. 42. The method of any one of claims 26 to 41, wherein the sintered S-LRMO material and / or quenched S-LRMO active material comprises loose powder having particles with an average maximum cross-sectional dimension of at least 0.02 microns and at most 1 micron.

43. The method of any one of claims 26 to 42, further comprising forming a cathode comprising S-LRMO active material.

44. 44. The method of claim 43, further comprising forming a lithium ion battery comprising the cathode, the anode, and the electrolyte.

45. The method of any one of claims 26 to 44, wherein M is a transition metal.

46. The cathode active material has the chemical formula: L[L) ｘ A ｙ M ｚ ]O ｂ (Wherein, A contains at least one of Na, K, Ca, and Mg, (x+y) is greater than 0 and less than 0.3; y>0.05, z=1−(x+y), M includes Mn and Ni, and b is 1.8 or more and 2.2 or less The cathode active material is represented by

47. The cathode active material is 1) exhibiting a specific capacity of more than 200 mAh / g when charged and discharged at a C / 20 rate; 2) For lithium-ion batteries, the average discharge voltage at a C / 20 rate decreases by less than 10% or less than 5% after 200 charge / discharge cycles; 3) For lithium-ion batteries, the capacity degradation at C / 4 rate over 200 cycles is less than 5%; 4) The C / 2 discharge specific capacity is at least 75% of the C20 discharge specific capacity; and 5) After 200 cycles, the full cycle discharge voltage at C / 20 rate is 3.5 V or more; 47. The cathode active material of claim 46, wherein the cathode active material exhibits one or more of:

48. (x+y) is equal to or greater than 0.1 and equal to or less than 0.25; y is greater than 0.05 and less than or equal to 0.15; b=2; the atomic ratio of A to lithium is in the range of 0.5:95.5 to 20:80; and M includes 50 atomic % or more and 80 atomic % or less of Mn, 20 atomic % or more and 50 atomic % or less of Ni, and 0 atomic % or more and 10 atomic % or less of Ti, Al, Fe, Co, or a combination thereof; 48. The cathode active material of claim 46 or 47.

49. The cathode active material has the formula: Li １．１４ Na ０．０６ Mn ０．６ Ni ０．２ O ２ 49. The cathode active material of claim 46, wherein

50. The cathode active material has the formula: Li １．０６ Na ０．１４ Mn ０．６ Ni ０．２ O ２ 49. The cathode active material of claim 46, wherein

51. The cathode active material has the formula: Li １．０１５ Na ０．１５５ Mn ０．５８ Ni ０．２５ O ２ 49. The cathode active material of claim 46, wherein

52. The cathode active material has the formula: Li １．０８１ Na ０．０５７ Mn ０．６５２ Ni ０．２１ O ２ 49. The cathode active material of claim 46, wherein

53. The cathode active material has the formula: Li １．０８１ Na ０．０５７ Mn ０．６５２ Ni ０．２１ O ２ 49. The cathode active material of claim 46, wherein

54. The cathode active material has the formula: Li １．０４１ Na ０．０６１ Mn ０．６２４ Ni ０．２７５ O ２ 49. The cathode active material of claim 46, wherein

55. The cathode active material has the formula: Li １．０６ K ０．１４ Mn ０．６ Ni ０．２ O ２ 49. The cathode active material of claim 46, wherein

56. The cathode active material has the formula: L[L) ｅ A ｆ M ｇ ]O ｈ wherein e is less than 0.06; f is 0.14 or more, g=1−(e+f), A contains at least one of Na, K, Ca, or Mg; M includes Mn and Ni, and h is equal to or greater than 1.8 and equal to or less than 2.2; The cathode active material of any one of claims 46 to 48.

57. 57. The cathode material of any one of claims 46 to 56, wherein there is a high degree of cation disorder such that no crystalline volumes larger than 3x3x3 nm exist in the active cathode material where the percentages of Ni, Mn, Na, and Li atoms differ by more than 3% compared to the average percentages of Ni, Mn, Na, and Li atoms in the bulk active cathode material.

58. 58. The cathode active material of any one of claims 46 to 57, wherein M is a transition metal.

59. 59. The cathode active material of any one of claims 46 to 58, wherein the cathode active material comprises a powder having particles with an average largest surface dimension of greater than or equal to 0.02 microns and less than or equal to 1 micron.

60. (a) a Li diffusivity at or below 30% state of charge that is at least one-third order of magnitude greater than that of otherwise identical unsubstituted LRMO; and (b) a lower fast pulse resistance than otherwise identical unsubstituted LRMO at 30% or less state of charge; 60. The cathode active material of any one of claims 46 to 59, exhibiting one or both of:

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