Substituted lithium-rich cathode material

Abstract

In accordance with various embodiments, there is provided a method of rapidly and inexpensively forming a crystallologically stable, highly durable, cobalt-free, lithium substituted lithium-rich metal oxide (S-LRMO) material in which the elements used to replace lithium are some combinations of Na, K, Ca, and Mg and are above levels that are typically considered to be doped. In some embodiments, a cathode active material comprising a lithium-rich metal oxide of a lithium substituted type is provided. For example, in some embodiments, the cathode active material comprises the chemical formula Li [LixAyMz] Ob, where A comprises at least one of Na, K, Ca, and / or Mg. In some embodiments, (x + y) is greater than 0 and less than 0.3, ygt; 0.05, z = 1-(x + y), M comprises Mn and Ni, and b is greater than or equal to 1.8 and less than or equal to 2.2.

Description

[0001] Related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 482,654, filed February 1, 2023, entitled “Substituted Lithium-Rich Cathode Materials,” and U.S. Provisional Patent Application No. 63 / 596,222, filed November 3, 2023, entitled “Substituted Lithium-Rich Cathode Materials,” each of which is incorporated herein by reference in its entirety for all purposes. Technical Field

[0003] Lithium-containing electrode materials and related synthesis methods are generally described. Background Technology

[0004] This invention relates to substituted lithium-rich lithium nickel manganese oxide cathode active materials and methods for preparing them. In particular, several embodiments relate to active materials in which a portion of the lithium is replaced by one or more alkali metal and / or alkaline earth metal elements.

[0005] Cobalt-containing cathode materials in lithium-ion batteries account for a significant portion of the cost of contemporary battery cells, with cobalt being the primary cost contributor. The complexity of the cobalt supply chain makes it an unstable commodity. Therefore, reliable cobalt-free lithium-ion battery cathode materials are needed. Similarly, the cost of lithium has increased significantly in recent years. Therefore, reducing the lithium content of cathode materials while maintaining electrochemical performance is of great interest. Consequently, improved materials and methods are required. Summary of the Invention

[0006] In some cases, the subject matter of this invention relates to related products, alternative solutions to specific problems, and / or a plurality of different uses of one or more systems and / or articles.

[0007] According to several embodiments, one method includes: sintering a substituted lithium-rich metal oxide (S-LRMO) material at a sintering temperature to form a sintered S-LRMO material; and rapidly cooling the sintered S-LRMO material from the sintering temperature to room temperature in less than 500 milliseconds to form a material of the formula Li[Li x A y M z ]O b(where A includes 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 ranges from 1.8 to 2.2) represents an S-LRMO active material. In some embodiments, during and / or after the synthesis of the S-LRMO material, although the S-LRMO material may contain other elements that substitute for lithium, at least a portion of the S-LRMO has a crystal structure of the "lithium-rich transition metal oxide" type.

[0008] According to several embodiments, a method includes using convection heating, microwave radiation (e.g., direct microwave radiation), and / or radiative heating to thermally decompose a precursor material to form a thermally decomposed substituted lithium-rich metal oxide (S-LRMO) material; sintering the thermally decomposed S-LRMO material to form a sintered S-LRMO material; and rapidly cooling the sintered S-LRMO material to form a material with the chemical formula Li[Li] x A y M z ]O b (where A includes 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 ranges from 1.8 to 2.2) represents a rapidly quenched S-LRMO material.

[0009] According to several implementation schemes, the cathode active material is made of the chemical formula Li[Li x A y M z ]O b The expression indicates that 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 ranges from 1.8 to 2.2.

[0010] Other advantages and novel features of the invention will become apparent when considered in conjunction with the accompanying drawings, based on the following detailed description of several non-limiting embodiments of the invention. In the event of conflicting and / or inconsistent disclosures in this specification and in documents incorporated by reference, this specification shall prevail. Attached Figure Description

[0011] Non-limiting embodiments of the invention will be described by way of example with reference to the accompanying drawings, which are schematic and not intended to be drawn to scale. In the drawings, each identical or substantially identical component shown is generally indicated by a single reference numeral. For clarity, not every component is labeled in every drawing, nor is every component of every embodiment of the invention shown, unless illustration is required to enable those skilled in the art to understand the invention. In the drawings:

[0012] The accompanying drawings, which are incorporated herein 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 illustrate the features of the invention.

[0013] Figure 1 Photographs of rapid quenching systems according to various embodiments of this disclosure.

[0014] Figure 2 This includes four sequential video capture time-lapse images taken at 30 frames per second, which, according to various embodiments of this disclosure, illustrate a rapid quenching process.

[0015] Figure 3 and Figure 4 To illustrate Li according to multiple embodiments of this disclosure x (Mn y Ni 1-y ) 2-x X-ray diffraction (XRD) patterns of O2 material (where x = 1.2 and y = 0.75) before and after rapid quenching.

[0016] Figure 5 To illustrate Li x (Mn y Ni 1-y ) 2-x Figure of the X-ray diffraction pattern of O2 material (where x = 1.16 and y = 0.7).

[0017] Figure 6 To illustrate Li using microwave heating and ultra-rapid quenching in several embodiments according to this disclosure x (Mn y Ni 1-y ) 2-x Figure of the X-ray diffraction pattern of O2 material (where x = 1.16 and y = 0.7).

[0018] Figure 7A is a transmission electron micrograph (TEM) atomic image of the prior art LRMO material before electrochemical cycling, without undergoing rapid quenching.

[0019] Figure 7B TEM HAADF atomic image of a non-substituted LRMO material subjected to rapid quenching according to several embodiments of this disclosure prior to electrochemical cycling.

[0020] For Li that has neither undergone microwave treatment nor rapid quenching (in this case, cooling is relatively slow on a metal plate) x (Mn y Ni 1-y ) 2-x A comparative example of O2 material (where x = 1.16 and y = 0.7), Figure 8A To illustrate the graph of battery potential versus specific capacity, and Figure 8B This is a graph showing the specific capacity relative to the cycle length.

[0021] For exemplary batteries containing LRMO active materials according to comparative embodiments of this disclosure, Figure 9A To illustrate the graph of battery potential versus specific capacity during break-in cycles, Figure 9B To illustrate the graph of battery potential versus specific capacity over time, Figure 9C To show a graph of specific capacity relative to cycle life at C / 20 rate, and Figure 9D The figure shows the discharge specific capacity relative to the number of cycles at a C / 5 rate with reference cycle C / 20.

[0022] Figure 10 To illustrate several embodiments according to this disclosure, a formula is provided: Li[Li 0.14 Na 0.06 Mn 0.6 Ni 0.2 Figure 1 shows the X-ray diffraction pattern of S-LRMO active material of O2.

[0023] Figure 11 To illustrate several embodiments according to this disclosure, a formula is provided: Li[Li 0.06 Na 0.14 Mn 0.6 Ni 0.2 Figure 1 shows the X-ray diffraction pattern of S-LRMO active material of O2.

[0024] Figure 12 To illustrate several embodiments according to this disclosure, a formula is provided: Li[Li 0.06 K 0.14 Mn 0.6 Ni 0.2 Figure 1 shows the X-ray diffraction pattern of S-LRMO active material of O2.

[0025] Figure 13 To illustrate several embodiments according to this disclosure, a formula is provided: Li[Li 0.06 Na 0.07 K 0.07 Mn 0.6 Ni 0.2 Figure 1 shows the X-ray diffraction pattern of S-LRMO active material of O2.

[0026] Figure 14 For having the formula: Li[Li 0.14 Na 0.06 Mn 0.6 Ni 0.2 Transmission electron micrograph and EDS elemental map of O2 S-LRMO material, showing that Mn and Ni are uniformly distributed throughout the material.

[0027] Figure 15 A graph illustrating electrochemical data of the charge / discharge performance of S-LRMO materials according to several embodiments of this disclosure is provided.

[0028] Figure 16 A graph illustrating electrochemical data of the charge / discharge performance of S-LRMO materials according to several embodiments of this disclosure is provided.

[0029] Figure 17 A graph illustrating the electrochemical data of cycle lifetimes of S-LRMO materials according to several embodiments of this disclosure is provided.

[0030] Figure 18 A graph illustrating electrochemical data of the charge / discharge performance of S-LRMO materials according to several embodiments of this disclosure is provided.

[0031] Figure 19 A graph illustrating electrochemical data of the efficiency as a function of cycle number for several embodiments of S-LRMO materials according to this disclosure.

[0032] Figures 20A to 20B A graph illustrating the electrochemical data of cycle lifetimes of S-LRMO materials according to several embodiments of this disclosure is provided.

[0033] Figure 21 A graph illustrating electrochemical data of the charge / discharge performance of S-LRMO materials according to several embodiments of this disclosure is provided.

[0034] Figure 22 A graph illustrating electrochemical data of the charge / discharge performance of S-LRMO materials according to several embodiments of this disclosure is provided.

[0035] Figure 23 A graph showing rate capacity data for potassium-substituted LRMO materials according to various embodiments of this disclosure.

[0036] Figure 24 To illustrate the use of materials according to several embodiments of this disclosure: Li[Li 0.015 Na 0.155 Mn 0.58 Ni 0.25 A graph showing the data from the first two charge / discharge cycles of a lithium metal half-cell manufactured with O2, which exhibits a specific capacity of over 250 mAh / g at a C / 20 rate.

[0037] Figure 25 To illustrate the material: Li[Li 0.015 Na 0.155 Mn 0.58 Ni 0.25 The graph shows cycle life data for lithium metal anode half-cells fabricated with O2, exhibiting stable capacity retention and repetitive reference cycles well exceeding 200 mAh / g. According to several embodiments of this disclosure, the median discharge voltage is also nominally stable, which is atypical for lithium-rich cathode materials.

[0038] Figures 26A to 26B A graph illustrating the diffusion rate data obtained by GITT (galvanostatic intermittent titration) is shown, illustrating the diffusion rate data of Li[Li] prepared as described under a lower charge state according to a set of embodiments. 0.015 Na 0.155 Mn 0.58 Ni 0.25 O2 exhibits superior lithium-ion transport compared to Li[Li] in at least some respects. 0.16 Mn 0.58 Ni 0.25 Lithium-ion transport in O2 materials.

[0039] Figure 27A and 27B To show the relationship with Li 1.17 Mn 0.58 Ni 0.25 O2 compared to using Li 1.081 Na 0.057 Mn 0.652 Ni 0.21 Diffusion data obtained from GITT (galvanostatic intermittent titration) of O2 using the same test cell (14 mm diameter circular electrode). Figure 27A (It illustrates Li prepared as described in a set of embodiments at a lower charge state.) 1.081 Na 0.057Mn 0.652 Ni 0.21 O2 is superior to Li in at least some aspects in lithium-ion transport. 1.17 Mn 0.58 Ni 0.25 Lithium-ion transport in O2 materials and fast pulse resistance ( Figure 27B (The image is missing.)

[0040] Figures 28A to 28C This demonstrates a sodium-substituted S-LRMO material (Li 1.081 Na 0.057 Mn 0.652 Ni 0.21 A graph showing the long-term (320 cycles) cyclic stability of O2: Figure 28A Capacity stability (C / 3 cycle per day, with a C / 15 reference cycle every 25 cycles); Figure 28B Average discharge voltage; and Figure 28C Coulomb efficiency. Detailed Implementation

[0041] According to several embodiments, methods are provided for rapidly and inexpensively forming crystallographically stable, highly durable, cobalt-free, lithium-substituted lithium-rich metal oxide (S-LRMO) materials, wherein the elements used to replace lithium are combinations of Na, K, Ca, and Mg, and at levels higher than typically considered doping. In some embodiments, cathode active materials comprising lithium-substituted lithium-rich metal oxides are provided. For example, in some embodiments, the cathode active material comprises the chemical formula Li[Li] x A y M z ]O b Where A includes at least one of Na, K, Ca, or Mg. Such methods and materials are described in more detail below.

[0042] In the context of this disclosure, it is appreciated that, for at least some lithium-containing cathode materials, it is of interest to find materials that can replace lithium in the material without having a significant detrimental effect on the material’s properties (e.g., without significantly altering the material’s crystal structure or performance).

[0043] LRMO materials

[0044] The following sections describe techniques for preparing unsubstituted LRMO materials. Unsubstituted LRMO materials can provide insights into substituted LRMO materials (S-LRMO materials) described in detail below. In the context of this disclosure, it is observed that in some embodiments, S-LRMO materials (e.g., the resulting S-LRMO exhibits favorable and desired crystallographic / structural and electrochemical performance properties) can be prepared using the techniques and conditions described for the unsubstituted LRMO materials described below.

[0045] In some embodiments, unsubstituted LRMO materials (e.g., LRMO materials that do not contain substituted Li alkali metals or alkaline earth metals) can be represented by the following general formula 1:

[0046] Li[Li x (Mn y Ni 1-y ) 1-x O2, (1)

[0048] Where x is greater than or equal to 0 and less than or equal to 0.3, and y is less than or equal to 0.95 and greater than or equal to 0.1, for example, less than or equal to 0.8 and greater than or equal to 0.5.

[0049] In some implementations, the non-substituted LRMO material is a lithium-rich lithium manganese nickel oxide material represented by Formula 2 below:

[0050] Li[Li (1 / 3-2x / 3) Mn (2 / 3-x / 3) Ni x O2,

[0051] (2) where x is greater than or equal to 0.1 and less than or equal to 0.4.

[0052] In some embodiments, unsubstituted LRMO materials can have different hexagonal (e.g., rhombic) and monoclinic phases in their pristine state (e.g., before their first charge). Therefore, in some embodiments, LRMO materials can be expressed by the formula: (1-x)[Li₂MnO₃]*x[LiMn a Ni (1-a) [O2] indicates that the first part of the expression represents the relative molar amount (1-x) of the monoclinic phase, while the second part represents the relative molar amount (x) of the rhombic phase. In some embodiments, the molar fraction "x" of the rhombic phase typically ranges from 0.8 to 0.95, while "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.

[0053] Multiple embodiments can provide non-substituted LRMO materials that exhibit high (e.g., >240 mAh / g) specific capacity and a high functional voltage window (e.g., greater than or equal to 2.0 V and less than or equal to 4.8 V) when used as active materials for cobalt-free cathodes.

[0054] According to several embodiments, methods for forming unsubstituted LRMO materials include rapid thermal processing and rapid (e.g., less than 10 seconds) or ultra-rapid (e.g., less than or equal to 500 milliseconds) quenching, which produces LRMO materials possessing excellent crystal structures with desired atomic order / disorder. These characteristics can provide unexpectedly robust long-term stability and performance when used as cathode active materials.

[0055] Certain unsubstituted LRMO materials (e.g., synthesized without rapid quenching and / or quenching in water) may be unsuitable as cathode active materials due to low rate performance and / or poor capacity retention, which is thought to be caused by structural instabilities, such as those resulting from oxygen loss, transition metal ion migration during use, and / or possible manganese dissolution. Unwilling to be bound by theory, the two most common aging mechanisms manifest as a decrease in average discharge voltage as the material slowly remodels into a dominant spinel structure, and a capacity loss after cycling due to mechanical and / or chemical degradation of the material.

[0056] Thermal decomposition and processing of non-substituted LRMO materials

[0057] LRMO materials (including substituted and unsubstituted LRMO materials) can be synthesized from precursor materials using various methods. Table 1 below lists specific methods that can be used to synthesize LRMO materials, including precursor synthesis of LRMO material cathodes, precursor materials, quenching methods, performance indicators, and discharge capacity (DC).

[0058] Table 1

[0059]

[0060] As shown in Table 1, the three main synthetic routes for LRMO materials include precipitation followed by combustion, hydrothermal synthesis, and sol-gel solution production followed by intermediate-temperature decomposition and high-temperature heat treatment (e.g., calcination, annealing, sintering).

[0061] As can be seen from Table 1, the number of studies exploring the influence of nickel composition on LRMO cathode performance decreases over time; among them, very few studies explore the presence of nickel with the formula Li[Ni] x Li (1 / 3–2x / 3) Mn (2 / 3-x / 3)The O2 cathode exhibits various nickel compositions or nickel compositions below x = 0.2. Table 1 also shows significant inconsistencies in the synthetic routes used across studies. Furthermore, few studies have conducted detailed comparative assessments relating the effects of synthetic methods on LRMO cathode performance. In LRMO materials, the order and disorder of transition metals can be important, and both composition and synthetic techniques can provide mechanisms influencing the degree of structural order and disorder. These compositional and synthetic variations may result in electrochemical behaviors (e.g., different defect concentrations) that could significantly impact the properties of LRMO cathodes.

[0062] To avoid being bound by specific theories, it is believed that when samples are rapidly cooled in liquid nitrogen, the particles are immediately shielded by the nitrogen cladding, similar to the Leidenfrost effect, which significantly reduces the heat transfer rate. It is also believed that in the preparation of some conventional cathode materials, lithium-containing cathode materials used in lithium-ion batteries should not come into contact with moisture because water would cause lithium to seep out of such cathode materials and form a lithium hydroxide coating on the material. Furthermore, water is known to cause malfunctions in lithium-ion batteries, such as those containing lithium iron phosphate cathode materials.

[0063] While not wishing to be bound by any particular theory, the inventors believe that the relatively slow conventional quenching and cooling processes lead to the agglomeration of metal oxides, resulting in the formation of separate nickel oxide and lithium manganese oxide phases. In particular, the nickel oxide phase may concentrate on the surface of LRMO material particles (e.g., microcrystals). Without being bound by theory, this surface agglomeration of nickel oxides, along with the segregation of nickel and manganese in the typical crystal structure, may at least partially contribute to the chemical instability of conventional LRMO active materials.

[0064] In contrast, the inventors unexpectedly determined that water quenching does not negatively affect the LRMO cathode and does not cause lithium to leach from such an LRMO cathode. Examples of embodiments in which water quenching is performed with unsubstituted LRMO are described in U.S. Patent Application Publication No. 2023 / 0015455 (which is incorporated herein by reference in its entirety for all purposes), filed July 5, 2022, as U.S. Patent Application No. 17 / 810,722 entitled “Lithium-Rich Nickel Manganese Oxide Battery Cathode Materials and Methods” and published January 19, 2023. Water quenching is considered to induce evaporation in the form of bubble nucleation and dissipation, which effectively increases the heat transfer rate. Therefore, water quenching is considered to have a heat transfer rate that can be approximately two orders of magnitude larger than that of liquid nitrogen quenching. Furthermore, water and additives solvated therein (i.e., other materials soluble in water) can react with high-temperature LRMO during and after quenching to produce favorable surface termination and / or coatings, which enhance electrochemical stability and durability when used in lithium-ion batteries. As described in more detail below, in some embodiments, the above methods, conditions, parameters, and / or processing steps can be applied to the substituted LRMO materials described in this disclosure.

[0065] Furthermore, in the context of Table 1, in many of the aforementioned prior art quenching routes, quenching is performed on pellets that are compacted and sintered or partially sintered from a single piece of material as a relatively large object (e.g., having a width on the order of centimeters). In contrast, in some embodiments of this disclosure, loose and / or ground powders having particles in the form of shapes and / or agglomerates with an average diameter of 20 micrometers or less (e.g., an average diameter greater than or equal to 0.1 micrometers and less than or equal to 20 micrometers, such as greater than or equal to 0.1 micrometers and less than or equal to 1 micrometer, or greater than or equal to 1 micrometer and less than or equal to 20 micrometers) are quenched such that when these particles come into contact with a quenching liquid (e.g., water), all the material cools rapidly at approximately the same rate. Other ranges are also possible. Each agglomerate may consist of microcrystals with an average size greater than or equal to 25 nm and less than or equal to 500 nm (e.g., greater than or equal to 50 nm and less than or equal to 200 nm). Other ranges are also possible. Each microcrystal may comprise a single crystal of LRMO material. Microcrystals can be partially or completely fused together within the agglomerate. If the microcrystals are completely fused within the agglomerate (i.e., within the powder particles), each microcrystal can comprise a single grain of powder particle separated from other individual grains within the same powder particle by grain boundaries. The average grain size of the powder particles can be greater than or equal to 25 nm and less than or equal to 500 nm, for example, greater than or equal to 50 nm and less than or equal to 200 nm. Other ranges are also possible. The agglomerate can be relatively porous, which allows water to reach the microcrystals within the agglomerate.

[0066] In some embodiments, the quenched material (e.g., LRMO or S-LRMO hereinafter referred to as such) comprises a powder containing particles (e.g., loose particles) with an average maximum cross-sectional size of less than or equal to 20 micrometers, less than or equal to 10 micrometers, less than or equal to 5 micrometers, less than or equal to 2 micrometers, or smaller. In some embodiments, the quenched material (e.g., LRMO or S-LRMO hereinafter referred to as such) comprises a powder containing particles (e.g., loose particles) with an average maximum cross-sectional size greater than or equal to 0.1 micrometers, greater than or equal to 0.2 micrometers, greater than or equal to 0.5 micrometers, greater than or equal to 1 micrometer, or larger. As mentioned above, combinations of these ranges are possible. Other ranges are also possible. In some embodiments, the quenched material (e.g., LRMO or S-LRMO hereinafter referred to as such) comprises a powder containing particles (e.g., loose particles) that are agglomerates of microcrystals with an average maximum cross-sectional size greater than or equal to 25 nm, greater than or equal to 50 nm, greater than or equal to 100 nm, or larger. In some embodiments, the quenched material (e.g., LRMO or S-LRMO hereinafter) comprises a powder containing aggregates of particles (e.g., loose particles) with an average maximum cross-sectional size of less than or equal to 500 nm, less than or equal to 300 nm, less than or equal to 200 nm, or smaller. Combinations of these ranges are possible. Other ranges are also possible. The average maximum cross-sectional size of the particles and / or crystals can be determined, for example, by transmission electron microscopy.

[0067] Rapid and ultra-rapid quenching of LRMO materials

[0068] According to various embodiments, LRMO cathode active materials can be formed by heat treatment (e.g., sintering, calcination, and / or annealing) and quenching of LRMO material powder. Specifically, the heat treatment may include a high-temperature process, wherein the LRMO material can be heated to a process temperature greater than or equal to 800°C and less than or equal to 1000°C (e.g., greater than or equal to 850°C and less than or equal to 950°C, or 900°C). Other ranges are also possible. The heat treatment can be carried out in any suitable heat treatment equipment, such as a furnace, for example a tube furnace, muffle furnace, rotary kiln, belt furnace, etc. In some embodiments, the heat treatment may optionally include one or more low-temperature precursor decomposition (e.g., calcination) processes, wherein the LRMO material is heated to a temperature above room temperature and below 800°C. For example, calcination may include heating the LRMO material to a temperature greater than or equal to 450°C and less than or equal to 550°C, such as 500°C, prior to the high-temperature process. Other ranges are also possible.

[0069] According to several embodiments, the quenching process may include transferring heated LRMO material into a quenching bath. For example, LRMO material may be dropped directly into the quenching bath from a heat treatment apparatus. As described in more detail below, in some embodiments, the methods, conditions, parameters, and / or processing steps described herein may be applied to the alternative LRMO materials described in this disclosure.

[0070] In existing methods, LRMO materials can be slowly cooled 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 can decrease slowly. The inventors have determined that slow cooling before entering the quench bath can lead to undesirable changes in the crystal structure of the sintered LRMO material. In other words, the temperature at which the sintered LRMO material enters the quench bath may be important for providing the desired crystal structure. For example, slow cooling may result in a less desirable crystal structure.

[0071] According to several embodiments, the transfer process can be configured such that the sintered LRMO material is placed in a quench bath at a temperature of at least 800°C (e.g., greater than or equal to 800°C and less than or equal to 950°C, or greater than or equal to 850°C and less than or equal to 925°C, or 900°C) after the sintering process. For example, the transfer time from the heat treatment equipment to the quench bath can be limited to 10 seconds or less, such as 1 second or less, such as less than 0.5 seconds, or 0.2 seconds or less. Therefore, the sintered LRMO material is cooled to room temperature (e.g., 25°C) from the heat treatment temperature (e.g., from a sintering temperature of at least 800°C, such as greater than or equal to 800°C and less than or equal to 950°C, or greater than or equal to 850°C and less than or equal to 925°C, or 900°C) within 10 seconds or less (e.g., less than 0.5 seconds, including 0.2 seconds or less). Other ranges are also possible. In this paper, an “ultra-rapid quenching process” can have a cooling time of less than 0.5 seconds (e.g., 0.2 seconds or less, such as greater than or equal to 0.1 seconds and less than or equal to 0.2 seconds), and a “rapid quenching process” can have a cooling time of 10 seconds or less (e.g., greater than or equal to 0.5 seconds and less than or equal to 10 seconds). Other ranges are also possible.

[0072] Sintered LRMO powder particles can be quenched in a quench bath at an average rate of at least 50 °C / s, for example, at least 50 °C / s and less than or equal to 10,000 °C / s. For example, sintered LRMO powder particles can be quenched at a rate greater than or equal to 87.5 °C / s and less than or equal to 8750 °C / s, for example, greater than or equal to 1750 °C / s and less than or equal to 8750 °C / s, including rates greater than or equal to 4375 °C / s and less than or equal to 8750 °C / s. Other ranges are also possible. Thus, sintered LRMO material can be quenched from a heat treatment temperature (e.g., sintering temperature) of at least 800 °C to the temperature of a quench bath (e.g., a room temperature water bath at 25 °C) in 10 seconds or less (e.g., less than 500 milliseconds, including 400 milliseconds or less, 300 milliseconds or less, or 200 milliseconds or less). For example, quenching can occur within a time period of less than or equal to 100 milliseconds and less than or equal to 400 milliseconds, or greater than or equal to 100 milliseconds and less than or equal to 200 milliseconds. Other ranges are also possible. As described in more detail below, in some embodiments, the methods, conditions, parameters, and / or processing steps described herein can be applied to the substituted LRMO materials.

[0073] The quench bath may contain a high-heat-capacity liquid solvent with an evaporation temperature below 200°C. For example, the quench bath may contain solvents such as water, oil, and / or alcohol. In some embodiments, the quench bath may contain additives configured to modify the surface of the LRMO material during quenching to improve the long-term chemical stability of the material. Additives may include acids, bases, alcohols, and / or dissolved carbonaceous substances, such as acids, alcohols, or carbonaceous substances dissolved in water.

[0074] For example, the quench bath can be an aqueous quench solution containing an acid additive at a concentration greater than or equal to 0.01 mol / L and less than or equal to 1.0 mol / L, such as greater than or equal to 0.1 mol / L and less than or equal to 1.0 mol / L, or greater than or equal to 0.5 mol / L and less than or equal to 1.0 mol / L, for example, sulfuric acid, hydrochloric acid, nitric acid, oxalic acid, citric acid, acetic acid, phosphoric acid, orthophosphoric acid, lithium hydroxide, sodium hydroxide, potassium hydroxide, and combinations thereof. Other ranges are also possible. The acid can be configured to stabilize the surface of the LRMO particles by reacting with and / or passivating the dangling bonds and / or OH end groups of the LRMO powder particles quenched in water containing the acid additive.

[0075] In some embodiments, acid quenching can induce the formation of spinel structures (e.g., surface layers) on the surface of quenched LRMO powder particles. These spinel structures can form a framework that stabilizes the particles and provides a three-dimensional pathway for lithium diffusion. Specifically, it is believed that acid can induce an exchange of Li ions between the particles and H ions from the acid, and a subsequent structural transformation of the particle surface, leading to the formation of a spinel surface layer.

[0076] In another embodiment, in addition to or instead of acid additives, the quenching solution may contain alcohol and / or carbohydrate additives. For example, the alcohol may include isopropanol or other alcohols, and the carbohydrate may include sugars, such as fructose, galactose-glucose, lactose, maltose, sucrose, and combinations thereof. In some embodiments, the quenching solution may contain carbohydrate additives at concentrations greater than or equal to 0.01 mol / L and less than or equal to 1.0 mol / L, for example, greater than or equal to 0.1 mol / L and less than or equal to 1.0 mol / L, or greater than or equal to 0.5 mol / L and less than or equal to 1.0 mol / L. Other ranges are also possible. In some embodiments, during the quenching process in water containing carbohydrate particles, the carbohydrates can form a dense, amorphous carbon coating on the surface of the LRMO powder particles. Not wishing to be bound by theory, the carbon coating can advantageously be permeable to Li ions but impermeable to the electrolyte of the Li-ion battery. The carbon coating can also allow for volume changes in LRMO microcrystals during battery charging and discharging. As described in more detail below, in some embodiments, the methods, conditions, parameters, and / or processing steps described herein can be applied to the alternative LRMO materials.

[0077] Rapid or ultra-rapid quenching processes can produce quenched LRMO materials with crystal structures that provide unexpected robustness and electrical properties. Specifically, the crystalline order in quenched LRMO materials (e.g., lithium-rich lithium manganese nickel oxide) produced by quenching processes can provide performance characteristics suitable for use as cathode active materials in lithium-ion batteries, offering energy density and charge storage stability characteristics similar to cathodes containing cobalt and high nickel content.

[0078] The quenching process can produce quenched LRMO material powder with a desired crystal structure and particle size. For example, the quenched sintered LRMO material can be a loose powder with an average particle size of 1 μm or smaller, such as an average particle size range of greater than or equal to 0.02 μm and less than or equal to 1 μm, or greater than or equal to 0.05 μm and less than or equal to 0.5 μm. Other ranges are also possible. In some embodiments, the quenched LRMO material can include crystalline phases and / or microcrystals with an average crystal size of greater than or equal to 25 nm and less than or equal to 500 nm, such as greater than or equal to 50 nm and less than or equal to 300 nm. Each powder particle can include one or more microcrystals. The loose sintered and quenched powder particles can be incorporated into a binder (e.g., a carbon binder) to form a cathode electrode for a Li-ion battery. Other ranges are also possible.

[0079] In some embodiments, the sintered and / or quenched LRMO material (or hereinafter, sintered and / or quenched S-LRMO material) comprises a loose powder containing particles with an average maximum cross-sectional size of less than or equal to 1 micrometer, less than or equal to 0.5 micrometers, or smaller. In some embodiments, the sintered and / or quenched LRMO material (or hereinafter, S-LRMO material) is a loose powder containing particles with an average maximum cross-sectional size greater than or equal to 0.02 micrometers, greater than or equal to 0.05 micrometers, greater than or equal to 0.1 micrometers, greater than or equal to 0.2 micrometers, or larger. Combinations of these ranges (e.g., greater than or equal to 0.02 micrometers and less than or equal to 1 micrometer, or greater than or equal to 0.05 micrometers and less than or equal to 0.5 micrometers) are possible. Other ranges are also possible.

[0080] In some embodiments, the sintered and / or quenched LRMO material (or hereinafter, sintered and / or quenched S-LRMO material) comprises a loose powder containing particles with an average maximum cross-sectional size of less than or equal to 500 nm, less than or equal to 300 nm, less than or equal to 200 nm, or smaller. In some embodiments, the sintered and / or quenched LRMO material (or hereinafter, sintered and / or quenched S-LRMO material) comprises a loose powder containing particles with an average maximum cross-sectional size of greater than or equal to 25 nm, greater than or equal to 50 nm, greater than or equal to 100 nm, greater than or equal to 150 nm, or larger. Combinations of these ranges (e.g., greater than or equal to 25 nm and less than or equal to 500 nm, greater than or equal to 50 nm and less than or equal to 300 nm) are possible. Other ranges are also possible.

[0081] Rapidly cooled LRMO materials can be dried to form LRMO active materials (e.g., heat-treated and rapidly cooled loose powder particles), which may have a hexagonal main phase and a monoclinic secondary phase. Thus, according to some embodiments, the ratio of hexagonal phase content to monoclinic phase content is greater than 1, for example, at least 2, and for example, at least 2 and less than or equal to 20. For example, sintered and rapidly cooled LRMO materials (e.g., dried active materials) can have a superlattice structure comprising hexagonal main phase layers separated by interlayers of monoclinic secondary phases. Alternatively, sintered and rapidly cooled LRMO materials may comprise a hexagonal phase matrix comprising monoclinic phase nanoregions (i.e., regions with a width less than micrometers). Mn and Ni can be uniformly distributed in the crystal structure of the LRMO material (e.g., excess Mn, Ni, and Li are homogeneously and uniformly distributed at transition metal lattice sites). For example, the crystalline grains of sintered and rapidly cooled LRMO materials can exhibit a uniform distribution of Mn and Ni atoms throughout the crystalline grains, such that when imaged by high-angle annular dark-field (HAADF) energy-dispersive X-ray spectroscopy (EDS) (i.e., in the EDS elemental map of a HAADF tunneling electron microscopy image), there are no Ni-rich or Mn-rich regions. In one embodiment, the term "no Ni-rich or Mn-rich regions in the crystalline grains" means the absence of crystalline volumes larger than 3 nm × 3 nm × 3 nm in which the ratio of Ni and Mn atoms differs by more than 3% from the average ratio of Ni and Mn atoms throughout the crystalline grains.

[0082] The crystal structure of the thus formed active LRMO material can be altered by electrochemical cycling. For example, when the active LRMO material is included as an active material in an electrochemical cell, the monoclinic phase may no longer be present at a detectable level after the first charge / discharge cycle. It is thought that the monoclinic phase may be consumed during Li ion insertion and / or deintercalation. As described in more detail below, in some embodiments, the above methods, conditions, parameters, and / or processing steps can be applied to the substituted LRMO materials described in this disclosure.

[0083] Rapid precursor decomposition in non-lithium-substituted LRMO materials

[0084] LRMO materials can be formed from a variety of precursor materials. For example, precursor materials can be organometallic compounds containing metals such as Li, Mn, and / or Ni, and solubilizers such as organic ligands. For example, precursor materials can include metal acetates, metal carbonates, metal nitrates, metal sulfates, and / or metal hydroxides.

[0085] In several embodiments, LRMO materials can be formed by thermally decomposing a precursor material, followed by sintering and quenching the resulting thermally decomposed LRMO material. The precursor material may comprise a gel formed via a sol-gel process. The gel may comprise a non-fluid material network (e.g., a colloidal network or a polymeric network) having a relatively low yield stress and expanding throughout its volume by a fluid (e.g., a liquid such as water). The gel may comprise a network formed by covalent bonds or via other mechanisms such as physical agglomeration. The sol-gel process may involve converting monomers into a colloidal solution (sol) that can serve as a precursor for the resulting gel (e.g., a gel of discrete particles or a network polymer). The inventors have determined that rapidly decomposing the precursor material gel can improve the uniformity of the LRMO material. For example, in the sol portion of the sol-gel process, stoichiometric amounts of a Li, Mn, and Ni-containing precursor may be mixed with water to form an aqueous mixture. For example, stoichiometric amounts of Li(CH3COO)2H2O, Mn(CH3COO)24H2O, and Ni(NO3)26H2O can be mixed to form an aqueous mixture. However, this disclosure is not limited to any particular precursor material. For example, in some embodiments, all acetate precursors or all nitrate precursors (i.e., lithium nitrate, manganese nitrate, and nickel nitrate) can be used. In some embodiments, the mixture may contain an excess of lithium acetate precursor of greater than or equal to 0.01 and less than or equal to 0.20 molar fraction to compensate for lithium loss during treatment. Other ranges are also possible.

[0086] The mixture can then be heated to form a precursor gel. For example, the mixture can be heated at a temperature greater than or equal to 90°C and less than or equal to 150°C, such as 100°C, for a period of time sufficient for gelation to occur. Other ranges are also possible.

[0087] The gel can then be thermally decomposed. For example, the gel can be heated at a temperature sufficient to remove (e.g., cause evaporation and / or decomposition) the gel's solubilizers (e.g., organic ligands) and / or solvents for a period of time, forming a thermally decomposed LRMO material.

[0088] Thermal decomposition can be carried out using conventional furnaces such as muffle box furnaces and / or tube furnaces. However, such apparatus typically has a slow heating and cooling rate of approximately greater than or equal to 1 °C / min and less than or equal to 10 °C / min, and does not employ any type of direct radiant heat input. Therefore, conventional furnaces may require at least 8 hours of processing time and a large amount of energy to form thermally decomposed LRMO material.

[0089] According to several embodiments, rapid (e.g., high-rate) heating methods are used to form thermally decomposed LRMO materials. For example, one embodiment may utilize microwave radiation to heat-treat LRMO precursor materials (i.e., to rapidly decompose LRMO precursors, such as gel precursors formed via a sol-gel process). For example, the microwave radiation may be direct microwave radiation. Other suitable types of heating for at least some embodiments include, but are not limited to, convection heating and / or radiation heating. Combinations of heating methods may be used. For example, thermal decomposition may involve convection heating, microwave radiation (e.g., direct microwave radiation), and / or radiation heating.

[0090] Microwaves are defined as electromagnetic radiation with wavelengths greater than or equal to 1 mm and less than or equal to 1 m. Widely used household microwave ovens utilize microwave radiation at frequencies of approximately 2.45 GHz. Regulations have limited the microwave frequencies that can be used in household and industrial applications. The mechanism of microwave heating is believed to be attributed to two types of factors: 1) the current flow under an external electric field generated by microwave radiation generates heat due to the Ohmic effect; and 2) dipoles present in ceramics reorient themselves under a changing electric field, generating heat due to friction.

[0091] Microwave heating allows for lower heat treatment temperatures (e.g., precursor thermal decomposition). Compared to conventional furnace heating processes, microwave heating also allows for shorter heating times due to its very rapid localized heating. The close mixing of precursor materials also allows for more efficient volumetric heating than conventional furnace heating processes.

[0092] In some embodiments, microwave heating is used to heat and decompose precursor materials, forming thermally decomposed LRMO materials. For example, precursor materials may include ligands and / or metals that are highly sensitive to microwave radiation. Therefore, multiple embodiments utilize microwave radiation to heat precursors and / or precursor gels to very high temperatures over very short time periods. Microwave heating has also been found to provide highly uniform heat distribution. Therefore, the use of microwave radiation can significantly alter the heating rate and the resulting microstructure and / or structure of the thermally decomposed LRMO material. For example, microwave heating of a precursor gel can produce a highly uniform thermally decomposed LRMO material. The thermally decomposed LRMO material can be in the form of inorganic ash that is free of organic components (e.g., free of carbon or containing an unavoidable amount of carbon). Therefore, microwave heating can allow the formation of thermally decomposed LRMO materials without the need for separate furnace firing (which can be omitted).

[0093] For example, the precursor gel can be provided to a microwave oven, where microwave radiation is used to decompose the gel and form a thermally decomposable LRMO material. For example, microwave radiation can be used to heat the gel to a temperature of at least 350°C, for example, a temperature greater than or equal to 350°C and less than or equal to 500°C, for a duration sufficient to allow the ligands and / or solvents of the gel to evaporate and form a thermally decomposable LRMO material (e.g., LRMO inorganic ash). Other ranges are also possible. In several embodiments, continuous or pulsed microwaves with power levels of 20,000 W / kg microwave material or lower can be used to form a thermally decomposable LRMO material within 30 minutes or less, for example, within a time period greater than or equal to 15 minutes and less than or equal to 30 minutes. Other ranges are also possible. Therefore, in order to form a thermally decomposable LRMO material with improved structural properties (e.g., uniform distribution of cations and / or metal oxides), the microwave-based heating process can be configured to rapidly remove (e.g., evaporate and / or burn) organic components from the precursor material.

[0094] While the microwave thermal decomposition of precursor gels formed via a sol-gel process has been described above, in other embodiments, precursors formed via microwave thermal decomposition may also be formed by other methods. For example, alternative precursor preparation methods may include mechanical grinding / mixing, freeze-drying rotary evaporation, or coprecipitation. Another example of an alternative precursor preparation method is the use of a static convection oven. In one embodiment of the coprecipitation method, a coprecipitated precursor comprising Mn and Ni hydroxides is mixed with lithium and / or other basic or alkali metal carbonates and / or hydroxides. The resulting mixture may be completely mixed and heat-treated. In one embodiment of the coprecipitation method, a precursor comprising Mn and Ni hydroxides may be mixed with lithium carbonate and coprecipitated. For example, solid precursor materials comprising Li₂CO₃ or LiOH, nickel oxides, and manganese oxides may also be used. Precipits prepared by any of these methods may also be subjected to microwave thermal decomposition to form thermally decomposed LRMO materials (i.e., LRMO inorganic ash). As described in more detail below, in some embodiments, the methods, conditions, parameters, and / or processing steps described above may be applied to the substituted LRMO materials described in this disclosure.

[0095] The thermally decomposed LRMO material (i.e., LRMO inorganic ash) can then be mixed and ground (e.g., milled) to form precursor LRMO powder. The precursor LRMO powder can then be heat-treated (e.g., sintered) in any suitable heat treatment apparatus (e.g., in a furnace, such as a tube furnace, muffle box, etc.) to form sintered LRMO material. For example, the precursor LRMO powder material can be heated (e.g., sintered) at a heat treatment temperature (e.g., at least 800°C, such as 900°C) for a period of greater than or equal to 12 hours and less than or equal to 24 hours, and then the sintered LRMO material can be rapidly or ultra-rapidly quenched as described above to form quenched LRMO material. The quenched LRMO material can then be dried and optionally re-ground (e.g., milled) into LRMO active material (e.g., active cathode material powder). This LRMO active cathode material powder can then be mixed with a binder or other inactive cathode material to form the cathode of a Li-ion battery.

[0096] According to various embodiments, methods for forming LRMO materials may include a combination of rapid heating (e.g., microwave heating) for at least a portion of the heat treatment, along with rapid or ultra-rapid quenching, to produce LRMO materials with unexpectedly high performance. Specifically, the process can produce LRMO materials with a high degree of atomic / cation disorder / homogeneity (which can be quantified using X-ray diffraction) and no or substantially no surface segregation of nickel or nickel oxide in the particles (e.g., microcrystals) (which can be observed using transmission electron microscopy). This combination of material properties produces cathode active materials that exhibit little to no capacity decay after 100 to 1000 charge / discharge cycles, significantly reduced or eliminated loss of average discharge voltage during cycling, and rate performance suitable for commercial applications.

[0097] According to various embodiments, methods including microwave heating and / or rapid / ultra-rapid quenching steps can be used to form LRMO active materials that do not suffer from the chemical instabilities of prior art LRMO materials. In particular, rapid or ultra-rapid quenching steps can be used to form LRMO active materials with reduced Ni surface segregation and increased structural uniformity, compared to conventional LRMO materials that are slowly cooled after sintering. In various embodiments, the above microwave heating process can be combined with rapid or ultra-rapid quenching to form LRMO active materials. For example, thermally decomposed LRMO materials formed using microwave decomposition can be sintered and then subjected to a rapid or ultra-rapid quenching process. As described in more detail below, in some embodiments, the above methods, conditions, parameters, and / or processing steps can be applied to the substituted LRMO materials described in this disclosure.

[0098] In one embodiment, the cathode electrode (i.e., the positive electrode) comprises an LRMO active material, said LRMO active material comprising powder embedded in a binder. The powder may have an average particle / aggregate size greater than or equal to 0.1 μm and less than or equal to 10 μm, and an average crystal (i.e., crystallite) size greater than or equal to 25 nm and less than or equal to 500 nm. The powder (e.g., embedded in the binder) may comprise particles with an average maximum cross-sectional size greater than or equal to 0.1 μm, greater than or equal to 0.2 μm, greater than or equal to 0.5 μm, greater than or equal to 1 μm, or larger. The powder (e.g., embedded in the binder) may comprise particles with an average maximum cross-sectional size less than or equal to 10 μm, less than or equal to 5 μm, less than or equal to 2 μm, or smaller. Combinations of these ranges (e.g., greater than or equal to 0.1 μm and less than or equal to 10 μm) are possible. Other ranges are also possible. The powder may have crystals (e.g., microcrystals) with an average maximum cross-sectional size greater than or equal to 25 nm, greater than or equal to 50 nm, greater than or equal to 100 nm, greater than or equal to 150 nm, or larger. The powder may also have crystals (e.g., microcrystals) with an average maximum cross-sectional size less than or equal to 500 nm, less than or equal to 300 nm, less than or equal to 200 nm, or smaller. Combinations of these ranges (e.g., greater than or equal to 25 nm and less than or equal to 500 nm) are possible. Other ranges are also possible. In one embodiment, the particles of the LRMO active material powder may have at least one of the following on their surface: a spinel surface layer, a carbon coating (e.g., produced by a carbohydrate additive in a quench bath), and / or passivated oxygen bonds (e.g., produced by an acid additive in a quench bath). The cathode electrode may be included in a battery (e.g., a lithium-ion battery), which also includes an anode electrode (i.e., a negative electrode), an electrolyte, and a separator.

[0099] Alternative LRMO materials

[0100] In one aspect, a substituted lithium-rich metal oxide (S-LRMO) material is provided, wherein at least a portion of the lithium is substituted with sodium, potassium, calcium, and / or magnesium. According to several embodiments, the cathode active material comprises a substituted lithium-rich metal oxide (S-LRMO) material, wherein at least a portion of the lithium is substituted with sodium, potassium, calcium, and / or magnesium. In this document, the S-LRMO material may also be referred to as a substituted alkali / alkaline-atom-rich metal oxide (ARMO) material. The S-LRMO material may have the following general formula:

[0101] Li[Li x A y M z ]O b ,

[0102] Where A is at least one alkaline earth element and / or alkali metal element other than lithium, and (x+y) is greater than 0 and less than 0.3, y>0.05, and 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 (based on the net oxidation state of M).

[0103] 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 metal element other than lithium, such as sodium, potassium, rubidium, cesium, and francium. In a set of exemplary embodiments, A is selected from Na, K, Ca, and / or Mg.

[0104] In some implementations, S-LRMO has the general formula:

[0105] Li[Li x A y M z ]O b ,

[0106] Wherein A is at least one alkaline earth element and / or alkali metal element other than lithium, such as Na, K, Ca and / or Mg, and (x+y) is greater than or equal to 0 and less than or equal to 0.3, y>0.05, and z=1-(x+y), M is a combination of transition metals and contains 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 (based 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, for example 0.2, and y is greater than or equal to 0.05 and less than or equal to 0.15, for example 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., in embodiments of unsubstituted LRMO materials) without any indication of other crystalline phases. In one embodiment, the S-LRMO material may have a different hexagonal (e.g., rhombic) phase and a monoclinic phase in its pristine state (e.g., before its first charge). In some embodiments, the two phases may be arranged in a layered structure. Based on the teachings of this specification, those skilled in the art will understand that the stoichiometry of “O2” in the chemical formula of LRMO and / or S-LRMO is not intended to be limited to a precise stoichiometry, and the actual elemental amount of oxygen may vary slightly (e.g., from greater than or equal to 1.9 moles of oxygen per unit mole of active material to less than or equal to 2.1 moles of oxygen per unit mole of active material), for example, to accommodate slight variations in the average transition metal oxidation state (e.g., transition metal oxidation state) of the other components of the material. For example, M may comprise 50 atomic% to 80 atomic% of Mn, 20 atomic% to 50 atomic% of Ni, and greater than or equal to 0 atomic% and less than or equal to 10 atomic% of other elements, including, for example, Ti, Al, Fe, Co, or any combination thereof. In several embodiments, up to 20% of the total Li content in the material can be replaced by one or more alkali metal elements other than Li and / or one or more alkaline earth metal elements. For example, 0.5%, 1%, 2%, 5%, 10%, or more of Li can be replaced by at least one of Na, K, Mg, and Ca. In some embodiments, up to 13%, 15%, 20%, or more of Li can be replaced by at least one of Na, K, Mg, and Ca. For example, 0.5% and less than 20%, such as 1% and less than 15%, or 2% and less than 13%, of Li can be replaced by at least one of Na, K, Mg, and Ca. Therefore, the atomic ratio of A to lithium in the above formula can be greater than or equal to 0.5:95.5 and less than or equal to 20:80.In other words, the ratio of A to (1+x) in the above formula can be greater than or equal to 0.5:95.5 and less than or equal to 20. Other ranges are also possible. When heat-treated as described above (e.g., sintering and rapid quenching), S-LRMO exhibits a classic lithium-rich crystal structure, displaying some combination of trigonal (R-3m) and monoclinic (C2 / m) crystal structure characteristics, and without a distinct secondary phase. In other words, S-LRMO comprises both hexagonal and monoclinic phases, with the trigonal crystal system belonging to the hexagonal crystal family (i.e., genus).

[0107] In some embodiments, 0.5% or more, 1% or more, 2% or more, 5% or more, 10% or more, of Li are replaced by Na. In some embodiments, up to 13% or 15% or 20% or more of Li are replaced by Na. For example, 0.5% or more and less than or equal to 20%, such as 1% or more and less than or equal to 15%, or 2% or more and less than or equal to 13%, of Li can be replaced by Na. Other ranges are also possible.

[0108] In some embodiments, 0.5% or more, 1% or more, 2% or more, 5% or more, 10% or more, of Li are replaced by K. In some embodiments, up to 13% or 15% or 20% or more of Li are replaced by K. For example, 0.5% or more and less than or equal to 20% of Li, such as 1% or more and less than or equal to 15%, or 2% or more and less than or equal to 13%, can be replaced by K. Other ranges are also possible.

[0109] In some embodiments, 0.5% or more, 1% or more, 2% or more, 5% or more, 10% or more, of Li are replaced by Mg. In some embodiments, up to 13% or 15% or 20% or more of Li are replaced by Mg. For example, 0.5% or more and less than or equal to 20% of Li, such as 1% or more and less than or equal to 15%, or 2% or more and less than or equal to 13%, may be replaced by Mg. Other ranges are also possible.

[0110] In some embodiments, 0.5% or more, 1% or more, 2% or more, 5% or more, 10% or more, of Li are replaced by Ca. In some embodiments, up to 13% or 15% or 20% or more of Li are replaced by Ca. For example, 0.5% or more and less than or equal to 20% of Li, such as 1% or more and less than or equal to 15%, or 2% or more and less than or equal to 13%, can be replaced by Ca. Other ranges are also possible.

[0111] In some implementations, the S-LRMO material (e.g., as a cathode active material) is composed of the formula Li[Li e A f M g O h The expression indicates that: e is less than or equal to 0.06, 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 also possible.

[0112] In some embodiments, cobalt is absent from the S-LRMO material or is present in a relatively small amount. For example, in some embodiments, the atomic percentage of cobalt in the S-LRMO is zero or less than or equal to 10 atomic%, less than or equal to 5 atomic%, less than or equal to 2 atomic%, less than or equal to 1 atomic%, less than or equal to 0.5 atomic%, less than or equal to 0.2 atomic%, less than or equal to 0.1 atomic%, less than or equal to 0.05 atomic%, less than or equal to 0.02 atomic%, less than or equal to 0.01 atomic%, less than or equal to 0.005 atomic%, less than or equal to 0.002 atomic%, less than or equal to 0.001 atomic%, or less. Other ranges are also possible.

[0113] In some implementations, S-LRMO (e.g., as a cathode active material) is composed of Li 1.14 Na 0.06 Mn 0.6 Ni 0.2 O2 represents the active material. In some embodiments, S-LRMO (e.g., as a cathode active material) is composed of Li... 1.06 Na 0.14 Mn 0.6 Ni 0.2 O represents the symbol. In some embodiments, S-LRMO (e.g., as a cathode active material) is composed of the formula Li 1.015 Na 0.155 Mn 0.58 Ni 0.25O2 represents the active material. In some embodiments, S-LRMO (e.g., as a cathode active material) is composed of Li... 1.013 Na 0.157 Mn 0.52 Ni 0.32 O2 represents the active material. In some embodiments, S-LRMO (e.g., as a cathode active material) is composed of Li... 1.06 K 0.14 Mn 0.6 Ni 0.2 O2 indicates the presence of O2. S-LRMO materials can be formed using methods similar to those described above for LRMO materials. For example, S-LRMO materials can be fabricated using precursor materials formed via sol-gel, solid-state, or co-precipitation methods. Precursor materials may include organometallic precursors of Li, Na, K, Ca, Mg, and one or more transition metals and / or Al. For example, the organometallic precursor 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 contains an excess of greater than or equal to 0.01 and less than or equal to 0.20 molar fractions of organometallic precursors of lithium, sodium, and / or potassium. In some embodiments, the precursor may contain an excess of greater than or equal to 0.01 and less than or equal to 0.20 molar fractions of organometallic precursors of lithium and / or sodium. For example, a sol-gel may contain an excess of greater than or equal to 0.01 and less than or equal to 0.20 molar fractions of organometallic precursors of lithium and / or sodium. In some embodiments, the precursor comprises an excess of lithium and / or sodium metal hydroxide precursor in a molar fraction greater than or equal to 0.01 and less than or equal to 0.20. For example, the sol-gel may comprise an excess of lithium and / or sodium metal hydroxide precursor in a molar fraction greater than or equal to 0.01 and less than or equal to 0.20. Other ranges are also possible. The precursor may be mixed (e.g., with a solution containing water) to form a mixture. The mixture of precursors may be heated to form a gel.

[0114] The precursor (e.g., as a mixture of substances such as a gel) can be thermally decomposed (e.g., to form an LRMO material). The precursor can be calcined at a temperature greater than or equal to 250°C and less than or equal to 600°C, for example, greater than or equal to 300°C and less than or equal to 500°C, for a period of time greater than or equal to 2 hours and less than or equal to 8 hours, for example, greater than or equal to 4 hours and less than or equal to 6 hours, to allow the precursor to thermally decompose and form an S-LRMO material. In some embodiments, microwave heating as discussed above can be used to thermally decompose the precursor. The decomposed precursor material can then be sintered at a sintering temperature (e.g., to form a sintered S-LRMO material). The decomposed precursor material can then be sintered at a temperature of at least 800°C, for example, greater than or equal to 850°C and less than or equal to 1000°C, or for example, greater than or equal to 900°C and less than or equal to 950°C, for a period of time greater than or equal to 8 hours and less than or equal to 14 hours, for example, greater than or equal to 9 hours and less than or equal to 12 hours, or greater than or equal to 10 hours and less than or equal to 11 hours, to form S-LRMO material. Other ranges are also possible.

[0115] In some embodiments, the S-LRMO material is sintered at a sintering temperature. The sintering temperature can refer to the temperature of the environment in which the S-LRMO is present during sintering (e.g., furnace temperature). In some embodiments, the sintering temperature is at least 800°C, at least 825°C, at least 850°C, at least 875°C, at least 900°C, or higher. In some embodiments, the sintering temperature is less than or equal to 1000°C, less than or equal to 950°C, less than or equal to 925°C, or lower. Combinations of these values ​​(e.g., at least 800°C and less than or equal to 1000°C, at least 850°C and less than or equal to 950°C, at least 900°C and less than or equal to 950°C) are possible. Other ranges are also possible.

[0116] In some embodiments, the precursor mixture contains an excess of alkali and / or alkaline substances, such that during heat treatment, not all Li, Na, K, and / or Mg substances become part of the formed active material, but rather become residues remaining in the powder as oxides or hydroxyoxides.

[0117] S-LRMO materials can be ultra-rapidly quenched from a quenching temperature to room temperature in a quenching fluid or quenching bath as described above to form S-LRMO active materials. For example, S-LRMO materials can be quenched from a sintering temperature of at least 800°C, such as greater than or equal to 800°C and less than or equal to 1000°C, or greater than or equal to 850°C and less than or equal to 950°C, to room temperature (e.g., 25°C) within a time period of less than or equal to 500 milliseconds, or greater than or equal to 1000 milliseconds and less than or equal to 100 milliseconds. Other ranges are also possible. In some embodiments, the quenching temperature and the sintering temperature can be the same or substantially the same temperature.

[0118] In some embodiments, the S-LRMO material is quenched from its sintering temperature (e.g., a sintering temperature of at least 800°C, such as greater than or equal to 800°C and less than or equal to 1000°C, or greater than or equal to 850°C and less than or equal to 950°C) to a quenching temperature in the range of greater than or equal to 10°C, greater than or equal to 15°C, greater than or equal to 20°C and / or less than or equal to 120°C, less than or equal to 100°C, less than or equal to 80°C, less than or equal to 60°C, less than or equal to 50°C, less than or equal to 45°C, less than or equal to 40°C, less than or equal to 35°C, less than or equal to 30°C, less than or equal to 30°C, less than or equal to 25°C, or lower. In some embodiments, the quenching temperature is room temperature (e.g., 25°C). The quenching can occur within less than or equal to 500 milliseconds, less than or equal to 400 milliseconds, less than or equal to 300 milliseconds, less than 200 milliseconds, and / or as low as 150 milliseconds, as low as 100 milliseconds, or less. Combinations of these ranges (e.g., quenching occurring within a time period greater than or equal to 100 milliseconds and less than or equal to 500 milliseconds, or greater than or equal to 100 milliseconds and less than or equal to 200 milliseconds) are possible. Other ranges are also possible.

[0119] In some embodiments, quenching (e.g., within the time period discussed above) includes bringing 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 thermal equilibrium (e.g., thermal equilibrium with its surrounding medium, such as a quench bath) in a temperature range of greater than or equal to 10°C, greater than or equal to 15°C, greater than or equal to 20°C and / or less than or equal to 120°C, less than or equal to 100°C, less than or equal to 80°C, less than or equal to 60°C, less than or equal to 50°C, less than or equal to 45°C, less than or equal to 40°C, less than or equal to 35°C, less than or equal to 30°C, less than or equal to 25°C, or lower (e.g., room temperature, such as 25°C). In some embodiments, quenching includes bringing at least 25 volume percentages (volume%), at least 50 volume%, at least 80 volume%, at least 90 volume%, at least 95 volume%, at least 98 volume%, at least 99 volume%, at least 99.9 volume%, or more (e.g., 100 volume%) of the sintered S-LRMO to thermal equilibrium (e.g., thermal equilibrium with its surrounding medium, such as a quench bath) within a temperature range of ≥10°C, ≥15°C, ≥20°C and / or ≤120°C, ≤100°C, ≤80°C, ≤60°C, ≤50°C, ≤45°C, ≤40°C, ≤35°C, ≤30°C, ≤25°C, or lower (e.g., room temperature, such as 25°C). Other ranges are also possible.

[0120] The quenching fluid may contain oil, alcohol, or water, and may optionally contain 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 quenching bath may contain water in an amount greater than or equal to 50% by weight, greater than or equal to 80% by weight, greater than or equal to 90% by weight, greater than or equal to 95% by weight, greater than or equal to 98% by weight, greater than or equal to 99% by weight, or greater (e.g., 100% by weight). Other ranges are also possible. As mentioned above, the quenching fluid or quenching bath may contain one or more additives, such as at least one acid or at least one carbohydrate (e.g., urea or sugar), or combinations thereof. In some embodiments, the pH of the quenching fluid or quenching bath (e.g., pH greater than 7, greater than or equal to 8, greater than or equal to 9, greater than or equal to 10, greater than or equal to 11, greater than or equal to 12, greater than or equal to 14, or greater) is alkaline. In some embodiments, the quench fluid or quench bath contains an alkali as an additive, such as LiOH, NaOH, and / or KOH.

[0121] In some embodiments, sintering can be performed in a furnace, such as a rotary furnace. For example, the S-LRMO material can be transferred from the furnace to a quenching fluid within 500 milliseconds or less, such as 200 milliseconds or less. In some embodiments, the time between removing the sintered S-LRMO material from the furnace and the occurrence of quenching (e.g., via transfer to a quench bath) is less than or equal to 500 milliseconds, less than or equal to 200 milliseconds, and / or as low as 100 milliseconds. Other ranges are also possible.

[0122] Excess alkali metals and / or alkaline earth metals, as well as Ni and Mn atoms, can be homogeneously and uniformly distributed throughout the transition metal lattice sites in the S-LRMO material, resulting in a crystalline volume greater than 3 nm × 3 nm × 3 nm in which the ratio of Ni, Mn, A, and Li atoms (where A is at least one of Na, K, Ca, or Mg) differs from the average ratio of Ni, Mn, Na, K, Ca, Mg, and Li atoms in the bulk material by more than 3%.

[0123] According to several embodiments, S-LRMO materials utilize a reduced amount of Li due to the substitution of Li with lower-cost elements. This provides a reduction in material cost compared to unsubstituted LRMO materials. Furthermore, S-LRMO materials offer unexpected capacity stability, rate capacity, and unexpectedly high voltage compared to conventional unsubstituted LRMO materials. Moreover, in the context of this disclosure, it is unexpectedly observed that the relatively high amount 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-LRMO) while maintaining substantially the same crystal structure and properties as the unsubstituted analogues. For example, unexpectedly, relatively high levels of lithium substitution (e.g., greater than 5% and up to 20%) can be obtained without the observation of a large amount of potentially harmful phenomena (e.g., the formation of a second crystalline phase). This contrasts with expectations from the literature, where it was previously reported that for nickel- and manganese-containing lithium metal oxide electrode active materials, a secondary crystalline phase (Na₂) was observed when some Li was substituted with Na. 0.7 MnO2) (Du, K. et al. (2013). "Sodium additive to improve rateperformance 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".] No large-scale occurrence of such a secondary phase has been observed in the case of the material disclosed herein. It is not intended to be bound by any particular theory, but it is considered that a contributing factor to the high level of lithium substitution observed without compromising the desired crystal and / or electrochemical properties is the use of the techniques of this disclosure (e.g., using rapid quenching, for example, in water).

[0124] In one embodiment, a method for forming an active material for a positive electrode of a lithium-ion battery includes quenching a powder of the active material in water. In another 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 prior to quenching, and the powder of the active material may be quenched at a rate of at least 1750°C / second.

[0125] In one embodiment, the active material comprises a layered, lithium-rich nickel-manganese oxide. Excess Li, Ni, and Mn atoms can be homogeneously and uniformly distributed throughout the transition metal lattice sites, such that there are no crystalline volumes larger than 3 nm × 3 nm × 3 nm in which the ratio of Ni, Mn, and Li atoms differs from the average ratio of Ni, Mn, and Li atoms in the bulk material by more than 3%. The active material powder particles can be in the form of agglomerates with an average size ranging from 0.1 μm to 20 μm, and the agglomerates of the active material powder consist of microcrystals with an average size ranging from 25 nm to 500 nm. After rapid quenching, the active material powder can contain a complex of hexagonal and monoclinic phases, and is a combination of the LiAMO2 R-3m phase and the (LiA)2MnO3C2 / m phase, wherein M is at least one of Ni or Mn, and A is some combination of non-lithium alkali metals and alkaline earth elements. The active material powder can contain a solid solution having a crystal structure possessing predominantly or completely C2 / m symmetry. The powder of the active material may contain a solid solution with a crystal structure that has a predominantly or completely R-3m symmetry.

[0126] In one embodiment, the quench water contains an additive in which it is solvated. The water may contain an additive at a concentration greater than or equal to 0.01 mol / L and less than or equal to 1.0 mol / L. 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 combinations thereof. In another embodiment, the additive includes a carbohydrate, which may be selected from fructose, galactose-glucose, lactose, maltose, sucrose, or combinations thereof.

[0127] In one embodiment, an active material is placed in the positive electrode of a lithium-ion battery cell, which also includes a negative electrode and an electrolyte. In this context, the positive electrode corresponds to the cathode, and the negative electrode corresponds to the anode. Prior to electrochemical cycling of the battery, the active material comprises a hexagonal and monoclinic phase, and after electrochemical cycling, the active material powder no longer contains the monoclinic phase.

[0128] In one embodiment, after 50 electrochemical cycles at a discharge rate up to C / 2, the cathode material in the battery cell has a specific capacity of at least 230 mAh / g (at a charge rate of C / 20).

[0129] In one embodiment, the lithium-ion battery cell includes: a negative electrode; an electrolyte; and a positive electrode comprising a layered lithium-rich nickel manganese oxide active material, wherein after 50 electrochemical cycles at a discharge rate up to C / 2, the battery cell has a specific capacity of at least 215 mAh / g (at a C / 20 rate).

[0130] In one embodiment, the active material powder particles are in the form of agglomerates with an average size greater than or equal to 0.1 μm and less than or equal to 10 μm, and the agglomerates of the active material powder are composed of microcrystals with an average crystal size greater than or equal to 25 nm and less than or equal to 500 nm. The active material powder particles may have at least one of a spinel surface layer, a carbon coating, or passivated oxygen bonds on their surface.

[0131] In some embodiments, the ratio of non-overlapping crystalline volumes larger than 3 nm × 3 nm × 3 nm containing Ni, Mn, and alkali metal and / or alkaline earth metal atoms in the material differs by more than 3% from the average ratio of Ni, Mn, Li, and alkali metal and / or alkaline earth metal atoms in the bulk material by less than 10% (e.g., less than 5%, less than 2%, less than 1%, less than 0.1%, or less). Such spatial distribution may be due to a high degree of cation disorder (e.g., due to the uniform distribution of Li, K, Na, Ca, Mg, Ni, and / or Mn atoms). Other ranges are also possible.

[0132] In some embodiments, the material does not contain a crystalline volume larger than 3 nm × 3 nm × 3 nm, wherein the ratio of Ni, Mn, and alkali metal and / or alkaline earth metal atoms differs by more than 3% from 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 the uniform distribution of Li, K, Na, Ca, Mg, Ni, and / or Mn atoms).

[0133] In one embodiment, the excess Li, K, Na, Ca, Mg, Ni and / or Mn atoms are homogeneously and uniformly distributed throughout the transition metal lattice sites, such that there is no crystalline volume greater than 3 nm × 3 nm × 3 nm in the material where the ratio of Ni, Mn and alkali metal and / or alkaline earth metal atoms differs from the average ratio of Ni, Mn and Li atoms in the bulk material by more than 3%.

[0134] Example

[0135] The following examples are intended to illustrate certain embodiments of the present invention, but do not represent the full scope of the invention.

[0136] Experimental Example

[0137] The following method is used to produce, according to one embodiment, a product having the formula Li x (Mn y Ni 1-y ) 2-x Unsubstituted LRMO powder containing O2 (where x = 1.16 and y = 0.7). Specifically, a sol-gel solid-state synthesis method was used to produce the precursor material gel. The sol synthesis involved forming an aqueous mixture containing stoichiometric amounts of Li(CH3COO)2H2O, Mn(CH3COO)24H2O, and Ni(NO3)26H2O. The mixture was heated at 100°C until a gel was formed. The gel was poured into an alumina crucible and calcined at 400°C for 90 minutes to obtain organic-free ash. The resulting ash was ground and calcined again in a crucible at 500°C for 3 hours, then allowed to cool naturally before re-grinding. After this, the powder was sintered at 900°C for 24 hours before quenching. All sintering was performed in a box furnace under ambient fume hood conditions. All quenching was performed after heating at 900°C for 12 to 24 hours.

[0138] Figure 1 Photographs of a rapid cooling system 100 according to several embodiments of this disclosure. Figure 2 This includes four sequential video capture time-lapse images taken at 30 frames per second, which, according to various embodiments of this disclosure, demonstrate a rapid quenching process.

[0139] Reference Figure 1 and Figure 2LRMO material is fed into a tube furnace 110, where it is heated to 900°C. The heated LRMO material is then removed from the tube furnace 110 and quenched to room temperature in a quench bath 120. The tube furnace 110 rotates during operation, causing its contents to be immediately poured into the quench bath 110. The time interval between the LRMO material leaving the furnace 110 at 900°C and its quenching to room temperature is less than 500 milliseconds, for example, less than 200 milliseconds, to form the LRMO active material. After quenching, the LRMO material is filtered from the water in the quench bath 120 and dried in a vacuum furnace.

[0140] In the first comparative example, the LRMO material was sintered at 900°C and then slowly cooled in furnace 110. In the second comparative example, the LRMO material was cooled by pouring it onto a metal plate after sintering. In the third comparative example, the LRMO material was first slowly cooled to room temperature and then inserted into tube furnace 110 for an ultra-rapid quenching step, wherein the LRMO material was held at 900°C for 30 to 120 minutes prior to the ultra-rapid quenching step.

[0141] In the first embodiment, a Na-substituted LRMO material was produced, wherein sodium replaced lithium content. The same formulation as above was used, but 5% of the lithium content was replaced with sodium, resulting in a final nominal chemical formula of Li[Li]. 0.14 Na 0.06 Mn 0.6 Ni 0.2 O2.

[0142] In the second embodiment, a Na-substituted LRMO material was produced, wherein sodium substituted for a portion of the lithium. A stoichiometric amount of MnNi-OH precursor was mixed with appropriate amounts of Li₂CO₃ and Na₂CO₃, wherein 12.5% ​​of the lithium content was replaced by sodium, resulting in a final nominal chemical formula of Li[Li₂]. 0.06 Na 0.14 Mn 0.6 Ni 0.2 O2, and the material is subjected to the heat treatment described above.

[0143] In the third embodiment, a K-substituted LRMO material was produced, wherein potassium substituted for a portion of the lithium. A stoichiometric amount of MnNi-OH precursor was mixed with appropriate amounts of Li₂CO₃ and K₂CO₃, wherein 12.5% ​​of the lithium content was replaced by potassium, resulting in a final nominal chemical formula of Li[Li₂]. 0.06 K 0.14 Mn 0.6 Ni 0.2 O2, and the material is subjected to the heat treatment described above.

[0144] In the fourth embodiment, a combined K and Na-substituted LRMO material was produced, wherein potassium and sodium substituted a portion of the lithium. A stoichiometric amount of MnNi-OH precursor was mixed with appropriate amounts of Li₂CO₃, K₂CO₃, and Na₂CO₃, wherein 12.5% ​​of the lithium content was replaced by equal amounts of sodium and potassium, resulting in a final nominal chemical formula of Li[Li]. 0.06 K 0.07 Na 0.07 Mn 0.6 Ni 0.2 O2, and the material is subjected to the heat treatment described above.

[0145] Material characterization

[0146] Figure 3 and Figure 4 Figures showing the X-ray diffraction (XRD) patterns of LRMO materials according to comparative and non-comparative embodiments of this disclosure. Figure 3 The XRD patterns in the samples were generated from layered LRMO active materials that had not undergone rapid quenching after immersion in water. Figure 4 The XRD pattern in the image was generated by rapidly cooling the layered LRMO active material after immersion in water.

[0147] Evaluation of the XRD patterns showed that the LRMO material has the expected hexagonal (e.g., rhombic) phase LiNiO2 associated space group (R-3m) and monoclinic phase (Li2NiO3 associated space group (C2 / c)).

[0148] Figure 5 To illustrate, according to several embodiments of this disclosure, Li is treated with microwave-heated sol-gel precursor material for 5 minutes prior to a high-temperature firing step. x (Mn y Ni 1-y ) 2-x A plot of X-ray diffraction results for O2 material (where x = 1.16 and y = 0.7). See reference. Figure 5 Of particular interest is the fact that this microwave-decomposed material exhibits X-ray diffraction patterns consistent with those of highly crystalline and optimized materials, including the space group (R-3m) associated with the rhombic phase LiNiO2 and the space group (C2 / c) associated with the monoclinic phase Li2NiO3. Therefore, the material is suitable for forming LRMO using annealing at 900 °C followed by rapid and / or ultra-rapid quenching, as described above.

[0149] Figure 6 To illustrate Li using microwave heating and ultra-rapid quenching in several embodiments according to this disclosure x (Mn y Ni 1-y )2-x A plot of X-ray diffraction results for O2 material (where x = 1.16 and y = 0.7). See reference. Figure 6 All expected peaks were present and well distinguished.

[0150] Figure 7A shows a high-angle annular dark-field imaging (HAADF) atomic image of a typical LRMO material before electrochemical cycling, obtained from a prior art example 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, Vol. 18, December 2020, p. 100518). As can be seen from these images, the initial LRMO material exhibits significant nickel and manganese segregation within the particles.

[0151] Figure 7B These are TEM HAADF atomic image micrographs of unsubstituted LRMO materials produced according to various embodiments of this disclosure, subjected to rapid quenching, prior to electrochemical cycling. As can be seen from these micrographs, the LRMO materials exhibit no significant nickel / manganese segregation within the particles. Therefore, rapid or ultra-rapid quenching reduces or eliminates nickel segregation on the particle surface, and nickel and manganese are uniformly mixed within the bulk of the LRMO material.

[0152] For Li that has neither undergone microwave treatment nor rapid quenching (in this case, cooling is relatively slow on a metal plate) x (Mn y Ni 1-y ) 2-x Examples of O2 materials (where x = 1.16 and y = 0.7), Figure 8A To illustrate the graph of battery potential versus specific capacity, and Figure 8B This is a graph showing the specific capacity relative to the cycle length.

[0153] For batteries containing non-substituted LRMO active materials according to comparative embodiments of this disclosure, Figure 9A To illustrate the graph of battery potential versus specific capacity during the trial operation cycle, Figure 9B To illustrate the graph of battery potential versus specific capacity over time, Figure 9C To show a graph of specific capacity relative to cycle life at C / 20 rate, and Figure 9DThe figure shows the discharge specific capacity relative to the number of cycles at a C / 5 rate with reference cycle C / 20.

[0154] Crystallization homogeneity, cation disorder and surface passivation

[0155] One method for assessing the disorder of metal cations in a material is to use the ratio of peak intensities in an X-ray diffraction pattern. Specifically, the ratio of the intensities of the (003) peak to the (104) peak is generally considered a rough measure of electrochemical activity in mixed cation materials with this 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 subjected to microwave treatment during the decomposition phase followed by ultrarapid quenching provide significantly higher indicators of electrochemical activity and lower cation order (and therefore higher cation disorder) than materials subjected to slow cooling.

[0156] Table 2 XRD peak ratio

[0157]

[0158] Table 2 shows the XRD peak intensity ratios of a first comparative LRMO material (row 1) subjected to slow quenching after sintering, a second unsubstituted LRMO material formed using an ultra-rapid quenching process after sintering, and exemplary S-LRMO materials (rows 2 and 3, respectively). The unsubstituted LRMO material has the formula Li[Li x (Mn y Ni 1-y ) 1-x [O2, where x = 0.2 and y = 0.75. Importantly, the exemplary ultra-rapidly quenched material exhibits XRD features showing an increase in atomic disorder within the material. Specifically, the exemplary material shows an increase in the ratio of the sum of the intensities of the (006) and (102) peaks to the intensity of the (101) peak, in this case, by 9%. This significant increase in cation disorder represents a more complete mixing (and therefore no aggregation) of Ni and Mn atoms in the material, as well as a more complete mixing of Li and the substituent elements in the transition metal sites. These data suggest that different states of matter can be generated based on the processing conditions used, and in particular the cooling rate used, and are also observed in S-LRMO materials.

[0159] Figures 10 to 13 This diagram illustrates X-ray diffraction patterns of S-LRMO materials containing various amounts of Na and / or K as described in the preceding sections, according to multiple embodiments of this disclosure. The S-LRMO materials were prepared using the heat treatment and ultrafast quenching processes disclosed above. Figures 10 to 13As shown, the S-LRMO material possesses the classical phase purity of LRMO materials. The XRD data are also consistent with materials exhibiting high cation mixing / disorder at the transition sites.

[0160] Figures 15 to 22 The graph illustrates the electrochemical performance of lithium-ion batteries formed using various defined S-LRMO materials. Specifically, Figure 15 and Figure 16 The figures show the voltage versus specific capacity of a battery containing S-LRMO material for the first two cycles and for cycles 13 through 26, respectively, where the S-LRMO material is represented by the formula Li[Li 0.14 Na 0.06 Mn 0.6 Ni 0.2 O2. Figure 17 The figure shows a graph of discharge specific capacity versus cycle number (i.e., cycle stability), and the inset shows a graph of voltage versus specific capacity for a battery containing S-LRMO material, where the S-LRMO material is of the formula Li[Li 0.14 Na 0.06 Mn 0.6 Ni 0.2 O2. Figure 18 A graph showing the charge and discharge specific capacity (i.e., voltage relative to specific capacity) of a battery containing S-LRMO material (where Na is 12.5% ​​substituted for lithium). Figure 19 A graph showing the number of cycles per 100 cycles of a battery containing S-LRMO active material relative to charge-discharge efficiency and discharge specific capacity. Figures 20A to 20B This includes a graph showing the discharge specific capacity of batteries containing S-LRMO materials relative to the number of cycles (i.e., cycle stability). Figure 20A ) and voltage versus specific capacitance graph ( Figure 20B ). Figures 18 to 2 The formula for the S-LRMO material in 0 is Li[Li 0.06 Na 0.14 Mn 0.6 Ni 0.2 O2. Figure 21 and Figure 22 This is a graph showing the voltage versus specific capacity of a battery containing S-LRMO material for the first two cycles, where the S-LRMO material has the formulas Li[Li 0.06 K 0.14 Mn 0.6 Ni 0.2 O2 and Li[Li 0.06 Na 0.07 K 0.07 Mn 0.6 Ni 0.2 O2.

[0161] like Figures 15 to 22 As shown, the S-LRMO active material exhibits excellent performance and stability, with little or no capacity decay over multiple cycles, which is in contrast to the rapid capacity and voltage decay exhibited by conventional Li-rich materials.

[0162] Figure 23 To show Li[Li 0.06 K 0.14 Mn 0.6 Ni 0.2 A graph showing the voltage versus specific capacity of O2 material discharge rate data. (See also:) Figure 23 As shown, the material exhibits high rate capacity, with a capacity of approximately 180 mAh / g at C / 2 rate. This favorable rate capacity is likely a result of the alkali metal atoms in the crystalline material creating easier lithium-ion transport pathways within the system, thereby achieving better conductivity and rate performance.

[0163] Figure 24 To illustrate the material used: Li[Li 0.015 Na 0.155 Mn 0.58 Ni 0.25 A graph showing the data from the first two charge / discharge cycles of a lithium metal half-cell manufactured with O2, which exhibits a specific capacity of over 250 mAh / g at a C / 20 rate.

[0164] Figure 25 To illustrate the material: Li[Li 0.015 Na 0.155 Mn 0.58 Ni 0.25 The graph shows the cycle life data of the lithium metal anode half-cell manufactured with O2, exhibiting stable capacity retention and repetitive reference cycles well exceeding 200 mAh / g. The median discharge voltage is also nominally stable, which is atypical for lithium-rich cathode materials.

[0165] In particular, the S-LRMO active material exhibits a stable capacity and voltage distribution, providing a significant improvement over conventional LRMO materials with similar compositions but without the substitutions or thermal treatments (e.g., no rapid quenching) described above. Batteries containing the S-LRMO active material exhibit specific capacities exceeding 260 mAh / g at C / 20, for example, 265 mAh / g to 275 mAh / g. Figure 16 As shown, containing Li 1.14 Na 0.06 Mn 0.6 Ni 0.2Batteries using O2 active materials exhibit stable discharge specific capacity and charge / discharge efficiency over dozens of cycles, demonstrating excellent stability and cycle life. Therefore, S-LRMO active materials exhibit less than 10% loss in average discharge voltage at C / 20 rate after 200 charge / discharge cycles of lithium-ion batteries (e.g., less than 5%, less than 2%, or less), and / or less than 5% capacity decay (e.g., less than 3%, less than 2%, or less) in C / 4 charge / discharge cycles of lithium-ion batteries, and / or a specific capacity exceeding 200 mAh / g when charged and discharged at C / 20 rate (e.g., exceeding 230 mAh / g, exceeding 250 mAh / g, or greater), and / or a C / 2 discharge specific capacity of at least 75% (e.g., at least 80%, at least 85%, at least 90%, or greater) of the C20 discharge specific capacity. In some embodiments, the S-LRMO active material exhibits a full cycle discharge voltage at C / 20 rate greater than or equal to 3.5V (e.g., greater than or equal to 3.8V, greater than or equal to 4.0V, or greater) after 200 cycles. In some embodiments, the S-LRMO active material exhibits a full cycle discharge voltage at C / 20 rate less than or equal to 10.0V (e.g., less than or equal to 8.0V, less than or equal to 6.0V, or less than or equal to 5.0V) after 200 cycles. Combinations of the above ranges are also possible (e.g., greater than or equal to 3.5V and less than or equal to 10.0V after 200 cycles).

[0166] In some embodiments, the S-LRMO active material (e.g., as a cathode active material) exhibits a Li diffusivity value at a charge state of 30% or less (e.g., at a temperature of 298 K) that is at least one-third order of magnitude larger (e.g., at least one-half order of magnitude or greater, at least one order of magnitude or greater, and / or up to 1.5 orders of magnitude, up to two orders of magnitude or greater) than that of the unsubstituted, otherwise identical LRMO. The unsubstituted, otherwise identical LRMO can have the same stoichiometry as S-LRMO, except that all lithium-substituted substances in S-LRMO (e.g., Na, K, Mg, Ca) are replaced by lithium.

[0167] In some embodiments, the S-LRMO active material (e.g., as a cathode active material) exhibits a fast pulse resistance value at a charge state of 30% or lower (e.g., at a temperature of 298 K) that is lower than that of other LRMOs with the same properties but without substitution (e.g., at least 20%, at least 30%, at least 40%, at least 50%, or lower).

[0168] Figures 10 to 13The X-ray data shown also demonstrate that high levels of lithium substitution (e.g., at least 12.5%) can be achieved without significantly affecting the crystal structure of LRMO or generating secondary crystalline phases. Regardless of the type and amount of substitution material used, all these X-ray diffraction patterns show only the expected lithium-rich crystalline phase structure. Figure 14 The TEM / EDS data shown indicate that, in this embodiment of the 5% Na-substituted material, Mn and Ni still have a uniform spatial distribution throughout the sample.

[0169] Electrochemical testing

[0170] The synthesized cathode material was mixed with Super-P carbon black and polyvinylidene fluoride (PVDF) at a ratio of 9.2:0.4:0.4, resulting in an active material comprising 92% of the total mass. The resulting blend was then mixed with approximately 15 ml of N-methyl-2-pyrrolidone for at least one hour prior to two 10-minute sonication steps. Afterward, the resulting slurry was further mixed on a hot plate at 100°C for at least 30 minutes, and then coated onto a 10 cm × 10 cm, 50 μm thick aluminum foil heated to above 100°C. The foil was then air-dried overnight in an oven at 70°C before perforation with a biopsy piercing device. These perforations are then used to manufacture 2032 coin batteries, which use lithium foil as the anode, an electrolyte consisting of a blend of carbonate and LiPF6 salt solution as the electrolyte, Celgard battery separators, 0.5mm stainless steel spacers, and wave springs on the cathode side to ensure mechanical contact within the battery; each coin battery is assembled and sealed in a dry, low-oxygen argon atmosphere using a coin battery press.

[0171] Electrochemical performance studies were conducted using a low-current battery tester to perform potential-limited constant-current testing on the coin cells manufactured in the above process using a constant current. The cells were cycled under constant current charge / discharge conditions between 4.8V and 2V at rates ranging from C / 20 to C / 2, as described above. Figures 15 to 22 The subject of discussion.

[0172] Figures 26A to 26B Exemplary galvanostatic intermittent titration data are shown, demonstrating that the diffusivity of Li in the substituted material is up to an order of magnitude higher at lower states of charge. This is of particular interest in some embodiments where the rate performance of the cathode material at lower voltages is often a problem; for example, in some cases, better diffusivity at lower states of charge allows the material to support higher power demands when in a battery cell near the end of its discharge.

[0173] Figure 27A and 27B To show the relationship with Li 1.17Mn 0.58 Ni 0.25 O2 compared to using Li 1.081 Na 0.057 Mn 0.652 Ni 0.21 Diffusion data obtained from GITT (galvanostatic intermittent titration) of O2 using the same test cell (14 mm diameter circular electrode). Figure 27A (It illustrates Li prepared as described in a set of embodiments at a lower charge state.) 1.081 Na 0.057 Mn 0.652 Ni 0.21 O2 is superior to Li in at least some aspects in lithium-ion transport. 1.17 Mn 0.58 Ni 0.25 Lithium-ion transport in O2 materials and fast pulse resistance ( Figure 27B The figure shows that below 3.3V, the diffusivity of S-LRMO is about half an order of magnitude higher than that of the unsubstituted material. S-LRMO also exhibits significantly lower fast pulse resistance.

[0174] Figures 28A to 28C This demonstrates a sodium-substituted S-LRMO material (Li 1.081 Na 0.057 Mn 0.652 Ni 0.21 A graph showing the long-term (320 cycles) cyclic stability of O2: Figure 28A Capacity stability (C / 3 cycle per day, with a C / 15 reference cycle every 25 cycles); Figure 28B Average discharge voltage; and Figure 28C Coulomb efficiency.

[0175] The foregoing description of the disclosed aspects is provided to enable any person skilled in the art to make or use the invention. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the invention. Therefore, the invention is not intended to be limited to the aspects shown herein, but is to be given the widest scope consistent with the principles and novel features disclosed herein.

[0176] While several embodiments of the invention have been described and illustrated herein, those skilled in the art will readily conceive of various other means and / or structures for performing the functions described herein and / or obtaining the results and / or one or more advantages described herein, and each of such changes and / or modifications is considered to be within the scope of the invention. More generally, those skilled in the art will readily understand that all parameters, dimensions, materials, and configurations described herein are intended to be exemplary, and actual parameters, dimensions, materials, and / or configurations will depend on one or more specific applications using the teachings of the invention. Those skilled in the art will recognize or be able to determine many equivalents of the specific embodiments of the invention described herein using only conventional experimentation. Therefore, it should be understood that the foregoing embodiments are presented by way of example only, and the invention can be practiced in ways other than those specifically described and claimed within the scope of the appended claims and their equivalents. The invention relates to the individual features, systems, articles, materials, and / or methods described herein. Furthermore, any combination of two or more such features, systems, articles, materials, and / or methods is included within the scope of the invention if such features, systems, articles, materials, and / or methods are not inconsistent with each other.

[0177] As used herein in the specification and claims, the phrase “at least a portion” means some or all. According to certain embodiments, “at least a portion” may mean at least 1% by weight, at least 2% by weight, at least 5% by weight, at least 10% by weight, at least 25% by weight, at least 50% by weight, at least 75% by weight, at least 90% by weight, at least 95% by weight, or at least 99% by weight, and / or up to 100% by weight in some embodiments.

[0178] Unless explicitly stated otherwise, nouns without quantifiers as used herein in the specification and claims shall be understood to mean “at least one / a kind”.

[0179] The phrase “and / or” as used herein in the specification and claims should be understood to mean “any one or both” of the elements so combined, i.e., elements that coexist in some cases and exist separately in others. Unless explicitly stated to the contrary, other elements may optionally exist besides those specifically indicated by the “and / or” clause, whether related to or unrelated to those specifically indicated. Thus, as a non-limiting example, when used in conjunction with open-ended language such as “comprising,” reference to “A and / or B” may in one embodiment refer to A without B (optionally including elements other than B); in another embodiment, refer to B without A (optionally including elements other than A); in yet another embodiment, refer to both A and B (optionally including other elements); and so on.

[0180] As used herein in the specification and claims, “or” should be understood to have the same meaning as “and / or” as defined above. For example, when items in a list are separated, “or” or “and / or” should be interpreted as inclusive, that is, including multiple elements or at least one of the elements in the list, but also including more than one, and optionally including other items not listed. Terms such as “only one” or “exact one”, or “consisting of” when used in a claim, will refer to including multiple elements or exactly one of the elements in the list. Generally, when preceded by exclusive terms such as “any one,” “one of,” “only one of,” or “exact one of,” the term “or” as used herein should only be interpreted as indicating an exclusive choice (i.e., one or the other but not both). When used in a claim, “consisting substantially of” should have the ordinary meaning as it is used in the field of patent law.

[0181] As used herein in the specification and in the claims, the phrase “at least one” when referring to a list of one or more elements should be understood to mean at least one element selected from any or more elements in the list, but does not necessarily include each element specifically listed in the list and at least one of each element, and does not exclude any combination of elements in the list. This definition also allows for the optional presence of elements other than those expressly indicated in the list of elements referred to by the phrase “at least one,” whether related to or unrelated to those expressly indicated elements. Therefore, as a non-limiting example, "at least one of A and B" (or equivalently, "at least one of A or B", or equivalently, "at least one of A and / or B") in one embodiment may refer to at least one A, optionally including more than one A, without B (and optionally including elements other than B); in another embodiment, may refer to at least one B, optionally including more than one B, without A (and optionally including elements other than A); in yet another embodiment, may refer to at least one A, optionally including more than one A, and at least one B, optionally including more than one B (and optionally including other elements); and so on.

[0182] Unless explicitly stated otherwise, the concentrations and percentages described herein are on a mass basis.

[0183] As used in this article, "weight%" is an abbreviation for weight percentage. As used in this article, "atomic%" is an abbreviation for atomic percentage.

[0184] Some implementations may embody methods in which multiple instances have been described. Actions performed as part of a method may be ordered in any suitable manner. Thus, implementations in which actions are performed in a different order than those shown may be constructed, which may include actions that are different from those described (e.g., more or fewer), and / or may involve performing some actions simultaneously, even if the actions are shown to be performed sequentially in the implementations specifically described above.

[0185] The use of ordinal terms such as “first,” “second,” “third,” etc., in claims to modify a claim element does not imply any priority, order of precedence, or sequence of actions of a method relative to another claim element, but is merely used as a marker to distinguish one claim element having a certain name from another element having the same name (but using an ordinal term), thereby differentiating the claim elements.

[0186] In the claims and the foregoing description, all transitional phrases such as “comprising,” “including,” “with,” “having,” “containing,” “involving,” “holding,” etc., shall be understood as open-ended, meaning including but not limited to. As set forth in Section 2111.03 of the U.S. Patent Examination Procedure Manual, only the transitional phrases “consisting of” and “consisting substantially of” shall be closed or semi-closed transitional phrases, respectively.

Claims

1. A method comprising: Sintering of substituted lithium-rich metal oxide (S-LRMO) materials at sintering temperature to form sintered S-LRMO materials; as well as The sintered S-LRMO material is rapidly cooled from the sintering temperature to a quenching temperature of less than or equal to 120°C within less than 500 milliseconds to form a rapidly cooled S-LRMO active material represented by the following formula: Li[Li x A y M z ]O b , in: A includes 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 greater than or equal to 1.8 and less than or equal to 2.

2.

2. The method according to claim 1, wherein the quenching temperature is greater than or equal to 10°C.

3. The method according to 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 greater than or equal to 900°C and less than or equal to 950°C.

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

7. The method according to any one of claims 1 to 6, wherein quenching the sintered S-LRMO material from the sintering temperature to the quenching temperature comprises quenching the sintered S-LRMO material from the sintering temperature to the quenching temperature within a time period of greater than or equal to 100 milliseconds and less than or equal to 200 milliseconds.

8. The method according to any one of claims 1 to 7, wherein: b＝2； The atomic ratio of A to lithium ranges from 0.5:95.5 to 20:80; and M contains Mn in amounts greater than or equal to 50 atomic% and less than or equal to 80 atomic%; Ni in amounts greater than or equal to 20 atomic% and less than or equal to 50 atomic%; and Ti, Al, Fe, Co, or combinations thereof in amounts greater than or equal to 0 atomic% and less than or equal to 10 atomic% 9. The method according to any one of claims 1 to 8, wherein: The sintering includes sintering the S-LRMO material in a furnace; and The quenching includes quenching the sintered S-LRMO material in a quenching bath.

10. The method according to any of the preceding claims, wherein the time between removing the sintered S-LRMO material from the furnace and quenching the sintered S-LRMO material in the quench bath is 200 milliseconds or less.

11. The method according to any of the preceding claims, wherein the quench bath comprises a water bath, a water bath containing an additive, an oil bath, or an alcohol bath, wherein the additive comprises an acid, a carbohydrate, an alcohol, or a combination thereof.

12. The method according to any of the preceding claims, wherein the quenching comprises quenching the sintered S-LRMO material in a quenching bath, wherein the quenching bath comprises a water bath, a water bath containing additives, an oil bath, or an alcohol bath, wherein the additives comprise acids, carbohydrates, alcohols, or combinations thereof.

13. The method according to any of the preceding claims, further comprising: A mixture of water and organometallic or metal hydroxide precursors of lithium and one or more transition metals; as well as The mixture is heated to form a gel; The gel is thermally decomposed to form the S-LRMO material.

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

15. The method according to any one of claims 13 to 14, wherein thermally decomposing the gel comprises using microwave radiation.

16. The method according to any one of claims 13 to 15, wherein: The gel contains an excess of lithium in a molar fraction greater than or equal to 0.01 and less than or equal to 0.20; and The S-LRMO material comprises inorganic materials containing lithium, sodium, nickel, manganese, and oxygen.

17. The method according to any one of claims 1 to 16, wherein the S-LRMO material is made of formula Li 1.14 Na 0.06 Mn 0.6 Ni 0.2 O2 represents.

18. The method according to any one of claims 1 to 16, wherein the S-LRMO material is made of formula Li 1.06 Na 0.14 Mn 0.6 Ni 0.2 O2 represents.

19. The method according to any one of claims 1 to 16, wherein the S-LRMO material is made of formula Li 1.015 Na 0.155 Mn 0.58 Ni 0.25 O2 represents.

20. The method according to any one of claims 1 to 16, wherein the S-LRMO material is made of formula Li 1.013 Na 0.157 Mn 0.52 Ni 0.32 O2 represents.

21. The method according to any one of claims 1 to 16, wherein the S-LRMO material is made of formula Li 1.06 K 0.14 Mn 0.6 Ni 0.2 O2 represents.

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

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

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

25. The method according to any of the preceding claims, wherein the sintered S-LRMO material and / or the quenched S-LRMO active material comprises loose powder, the loose powder comprising particles with an average maximum cross-sectional size greater than or equal to 0.02 micrometers and less than or equal to 1 micrometer.

26. A method comprising: The precursor material is thermally decomposed using convection heating, microwave radiation, and / or radiative heating to form a thermally decomposed substituted lithium-rich metal oxide (S-LRMO) material. The thermally decomposed S-LRMO material is sintered to form a sintered S-LRMO material; and The sintered S-LRMO material is rapidly quenched to form a rapidly quenched S-LRMO material represented by the following chemical formula: Li[Li x A y M z ]O b , in: A includes 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 greater than or equal to 1.8 and less than or equal to 2.

2.

27. The method of claim 26, wherein the thermal decomposition is performed using microwave radiation.

28. The method according to any one of claims 26 to 27, wherein the precursor material comprises at least one of the acetate, carbonate, nitrate, sulfate or hydroxide of Li, Na, Mn and Ni, or a metal organometallic precursor or metal hydroxide precursor.

29. The method according to any one of claims 26 to 28, wherein: b＝2； The atomic ratio of A to lithium ranges from 0.5:95.5 to 20:80; and M contains Mn in amounts greater than or equal to 50 atomic% and less than or equal to 80 atomic%; Ni in amounts greater than or equal to 20 atomic% and less than or equal to 50 atomic%; and Ti, Al, Fe, Co, or combinations thereof in amounts greater than or equal to 0 atomic% and less than or equal to 10 atomic% 30. The method according to any one of claims 26 to 29, further comprising: A mixture of water and at least Li, Na, Ni and Mn of the organometallic precursors is formed; as well as The mixture is heated to form a gel. The step of thermally decomposing the precursor material includes heating the gel using the microwave radiation.

31. The method of claim 30, wherein the mixture comprises an excess of the organometallic precursor of Li, Na, and K in a molar fraction greater than or equal to 0.01 and less than or equal to 0.

20.

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

20.

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

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

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

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

37. The method according to any one of claims 26 to 36, wherein the S-LRMO material is made of formula Li 1.14 Na 0.06 Mn 0.6 Ni 0.2 O2 represents.

38. The method according to any one of claims 26 to 36, wherein the S-LRMO material is made of formula Li 1.06 Na 0.14 Mn 0.6 Ni 0.2 O2 represents.

39. The method according to any one of claims 26 to 36, wherein the S-LRMO material is made of formula Li 1.015 Na 0.155 Mn 0.58 Ni 0.25 O2 represents.

40. The method according to any one of claims 26 to 36, wherein the S-LRMO material is made of formula Li 1.013 Na 0.157 Mn 0.52 Ni 0.32 O2 represents.

41. The method according to any one of claims 26 to 36, wherein the S-LRMO material is made of formula Li 1.06 K 0.14 Mn 0.6 Ni 0.2 O2 represents.

42. The method according to any one of claims 26 to 41, wherein the sintered S-LRMO material and / or the quenched S-LRMO active material comprises loose powder, the loose powder comprising particles with an average maximum cross-sectional size greater than or equal to 0.02 micrometers and less than or equal to 1 micrometer.

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

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

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

46. ​​A cathode active material represented by the following chemical formula: Li[Li x A y M z ]O b , in: A includes 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 greater than or equal to 1.8 and less than or equal to 2.

2.

47. The cathode active material according to claim 46, wherein the cathode active material exhibits one or more of the following: 1) When charged and discharged at a C / 20 rate, the specific capacity exceeds 200mAh / g; 2) The average discharge voltage loss at C / 20 rate is less than 10% or less than 5% after 200 charge / discharge cycles in lithium-ion batteries; 3) The capacity decay of the lithium-ion battery is less than 5% during 200 C / 4 charge / discharge cycles; 4) At least 75% of the C2 discharge specific capacity; and 5) A full-cycle discharge voltage of greater than or equal to 3.5V at C / 20 rate after 200 cycles.

48. The cathode active material according to any of the preceding claims, wherein: (x+y) is greater than or equal to 0.1 and less than or equal to 0.

25. y is greater than 0.05 and less than or equal to 0.

15. b＝2； The ratio of A to lithium is greater than or equal to 0.5:95.5 and less than or equal to 20:80; and M contains Mn in amounts greater than or equal to 50 atomic% and less than or equal to 80 atomic%; Ni in amounts greater than or equal to 20 atomic% and less than or equal to 50 atomic%; and Ti, Al, Fe, Co, or combinations thereof in amounts greater than or equal to 0 atomic% and less than or equal to 10 atomic% 49. The cathode active material according to any one of claims 46 to 48, wherein the cathode active material is composed of the formula Li 1.14 Na 0.06 Mn 0.6 Ni 0.2 O2 represents.

50. The cathode active material according to any one of claims 46 to 48, wherein the cathode active material is composed of formula Li 1.06 Na 0.14 Mn 0.6 Ni 0.2 O2 represents.

51. The cathode active material according to any one of claims 46 to 48, wherein the cathode active material is composed of formula Li 1.015 Na 0.155 Mn 0.58 Ni 0.25 O2 represents.

52. The cathode active material according to any one of claims 46 to 48, wherein the cathode active material is composed of formula Li 1.081 Na 0.057 Mn 0.652 Ni 0.21 O2 represents.

53. The cathode active material according to any one of claims 46 to 48, wherein the cathode active material is composed of formula Li 1.081 Na 0.057 Mn 0.652 Ni 0.21 O2 represents.

54. The cathode active material according to any one of claims 46 to 48, wherein the cathode active material is composed of formula Li 1.041 Na 0.061 Mn 0.624 Ni 0.275 O2 represents.

55. The cathode active material according to any one of claims 46 to 48, wherein the cathode active material is composed of formula Li 1.06 K 0.14 Mn 0.6 Ni 0.2 O2 represents.

56. The cathode active material according to any one of claims 46 to 48, wherein the cathode active material is composed of the formula Li[Li e A f M g O h It means that, among them: e is less than 0.06, 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.

57. The cathode active material according to any one of claims 46 to 56, wherein there is a high degree of cation disorder, such that there is no crystalline volume greater than 3 nm × 3 nm × 3 nm in the cathode active material, wherein the ratio of Ni, Mn, Na and Li atoms differs from the average ratio of Ni, Mn, Na and Li atoms in the bulk cathode active material by more than 3%.

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

59. The cathode active material according to any one of claims 46 to 58, wherein the cathode active material comprises a powder containing particles with an average maximum cross-sectional size greater than or equal to 0.02 micrometers and less than or equal to 1 micrometer.

60. The cathode active material according to any one of claims 46 to 59, wherein the substituted cathode active material exhibits one or both of the following: (a) At a charge state of 30% or lower, the Li diffusivity is at least one-third of an order of magnitude greater than that of the otherwise identical non-substituted LRMO; and (b) At a charge state of 30% or lower, the fast pulse resistance value is lower than that of the non-substitute type of LRMO with the same other aspects.

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