A lithium-rich manganese-based doped precursor, a preparation method thereof, and a cathode material and a battery

Abstract

The application provides a doped lithium-rich manganese-based precursor, a preparation method of the doped lithium-rich manganese-based precursor, a positive electrode material and a battery, and relates to the technical field of battery positive electrode material preparation. In the precursor synthesis process, fluorine and phosphorus doping elements are synchronously added, can be uniformly dispersed in the precursor, the nucleation and growth mode of the precursor is induced by using the adsorption characteristics and synergistic induction effect of the fluorine and phosphorus elements, and a precursor morphology with needle-like radial arrangement is synthesized. Due to the inheritance of the material to the precursor, the morphology of the lithium-rich material corresponding to the morphology is beneficial to the migration and transmission of lithium ions from the inside of the material to the outside, and the stress is small, and the structure is more stable in the cycle process.

Description

Technical Field

[0001] This invention relates to the field of battery cathode material preparation technology, and in particular to a lithium-rich manganese-based precursor, its preparation method, cathode material, and battery. Background Technology

[0002] With the development of electric vehicles, large-scale energy storage, and microdevices, there is a growing demand to further improve the energy density, power density, cycle life, and safety of existing secondary batteries, while reducing costs. Cathode materials are a key factor determining battery energy density, safety performance, and cost. Lithium-rich manganese-based cathode materials, due to their unique electrochemical reaction mechanism, can release a much higher discharge specific capacity (greater than 250 mAh / g) than existing conventional cathode materials, and possess significant advantages such as high voltage, good thermal stability, and low raw material cost, making them a recent research hotspot and considered one of the most promising cathode materials for future high-energy-density lithium batteries. However, lithium-rich materials suffer from problems such as low lithium-ion diffusion coefficients, structural phase transitions caused by oxygen evolution during high-voltage cycling, and transition metal dissolution, leading to deteriorated cycle performance, especially at high temperatures. Furthermore, the discharge voltage decays rapidly with the phase transition; these are intrinsic problems that restrict their commercialization.

[0003] To overcome the above problems, existing technologies mainly employ elemental doping and surface coating to improve the electrochemical performance of lithium-rich materials. Patent CN 112234176 A adds magnesium and fluorine to carbonate precursors to achieve doping, which can effectively improve the crystal stability of lithium-rich materials and suppress voltage decay. However, the carbonate precursor precipitation is incomplete, the decomposition rate is high during sintering, the material has a high specific surface area, and a low compaction density.

[0004] Meanwhile, the morphology and properties of the precursor are also key factors affecting the performance of lithium-rich materials. Currently, lithium-rich precursors are usually synthesized using the conventional hydroxide co-precipitation method. Due to the high manganese content, the primary particles of the precursor tend to form thick, large hexagonal plate-like morphologies. These large primary particle morphologies are difficult to lithilate during sintering. Moreover, since the sintered material inherits the morphology of the precursor, the primary particles of the sintered material are also very thick and large, resulting in a long lithium-ion diffusion path and unsatisfactory electrochemical performance such as capacity utilization and rate performance.

[0005] Therefore, it is necessary to develop a simple and effective method to improve the electrochemical performance of lithium-rich materials and to control the morphology of primary particles of lithium-rich precursors. Summary of the Invention

[0006] This invention simultaneously incorporates fluorine and phosphorus dopants during precursor synthesis, ensuring uniform dispersion within the precursor. Fluorine, with its high electronegativity and strong bonding with transition metals, effectively stabilizes the bulk and surface structure of the material, significantly improving cycle stability and voltage drop. Phosphorus forms Li3PO4 with lithium during the high-temperature lithiation sintering of the precursor, possessing a high lithium-ion diffusion coefficient and providing a rapid diffusion channel for lithium ions. This reduces the impedance of lithium-rich materials, enhancing their rate performance and electrochemical properties. Furthermore, the adsorption characteristics and synergistic inductive effects of fluorine and phosphorus induce the nucleation and growth of the precursor, synthesizing a precursor morphology with needle-like radial orientation. Due to the material's inheritance from the precursor, this morphology in lithium-rich materials facilitates lithium-ion migration from the interior to the exterior, while also reducing stress and enhancing structural stability during cycling.

[0007] One of the objectives of this invention is to provide a lithium-rich manganese-based precursor.

[0008] The second objective of this invention is to provide a method for preparing the doped lithium-rich manganese-based precursor.

[0009] The third objective of this invention is to provide a cathode material prepared from the doped lithium-rich manganese-based precursor.

[0010] The fourth objective of this invention is to provide a battery comprising the positive electrode material.

[0011] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted:

[0012] In a first aspect, the present invention provides a lithium-rich manganese-based precursor, wherein the lithium-rich manganese-based precursor is a nickel-manganese hydroxide or a nickel-cobalt-manganese hydroxide doped with fluorine and phosphorus elements.

[0013] The doped lithium-rich manganese-based precursor is composed of secondary spherical or near-spherical particles made up of primary particles. The primary particles have a needle-like morphology and are oriented radially along the secondary particles.

[0014] In some embodiments, the diameter of the primary particles is 10–100 nm, and the aspect ratio of the primary particles is ≥3. A schematic diagram of the diameter and aspect ratio is shown below. Figure 1 As shown, D2 is the diameter, and the length-to-diameter ratio is the ratio of the longest diameter passing through the interior of the particle to the longest diameter perpendicular to it, i.e., D1 / D2, which tends to be the average length and diameter value of needle-shaped or rod-shaped primary particles.

[0015] In some embodiments, the molar ratio of manganese, nickel, and cobalt in the doped lithium-rich manganese-based precursor is 0.55–0.80:0.10–0.45:0–0.20.

[0016] In some embodiments, the molar ratio of fluorine to the total molar ratio of nickel, cobalt and manganese in the lithium-rich manganese-based precursor is 0.002 to 0.010:1, preferably 0.003 to 0.006:1; and the molar ratio of phosphorus to the total molar ratio of nickel, cobalt and manganese is 0.003 to 0.010:1, preferably 0.004 to 0.008:1.

[0017] Secondly, the present invention provides a method for preparing a lithium-rich manganese-based precursor, comprising the following steps:

[0018] Soluble nickel salt, soluble manganese salt, and optionally soluble cobalt salt are dissolved in water to form a metal salt solution. Soluble fluoride and phosphate are dissolved in an alkaline solution to form a precipitant solution. Under controlled reaction conditions, the metal salt solution, precipitant solution, and complexing agent are simultaneously added to the reactor to form a precipitate. After filtration, washing, and drying, F and P-doped lithium-rich manganese-based precursors are obtained.

[0019] Preferably, the soluble nickel salt includes any one or a combination of at least two of nickel sulfate, nickel acetate, nickel chloride, or nickel nitrate; the soluble manganese salt includes any one or a combination of at least two of manganese sulfate, manganese acetate, manganese chloride, or manganese nitrate; and the soluble cobalt salt includes any one or a combination of at least two of cobalt sulfate, cobalt acetate, cobalt chloride, or cobalt nitrate.

[0020] Preferably, the concentration of the metal salt solution is 1-4 mol / L.

[0021] Preferably, the soluble fluoride includes one or more of NH4F, NaF, and KF; the soluble phosphate includes one or more of (NH4)3PO3, (NH4)2HPO3, NH4H2PO3, Na3PO3, Na2HPO3, NaH2PO3, K3PO3, K2HPO3, and KH2PO3.

[0022] Preferably, the concentration of the alkaline solution is 1-4 mol / L.

[0023] Preferably, the complexing agent is ammonia water with a concentration of 0.05-2 mol / L.

[0024] Preferably, the reaction conditions include: pH 10-12, temperature 40-60℃, and stirring speed 600-1000 r / min.

[0025] Thirdly, the present invention provides a cathode material obtained by sintering a mixture of the above-mentioned lithium-doped manganese-based precursor and a lithium source.

[0026] Preferably, the lithium source includes any one or a combination of at least two of lithium acetate, lithium nitrate, lithium carbonate, and lithium hydroxide;

[0027] Preferably, the molar ratio of lithium to the total amount of metals (nickel, cobalt, manganese) in the lithium source is 1.1-1.6:1.

[0028] Preferably, the sintering conditions include: the sintering atmosphere is air or oxygen, sintering at 400-600℃ for 4-10 hours, and then sintering at 800-1000℃ for 6-20 hours.

[0029] Fourthly, the present invention provides a battery comprising the above-mentioned positive electrode material.

[0030] The battery is a lithium-ion battery.

[0031] Beneficial effects:

[0032] 1. This invention provides a lithium-rich manganese-based precursor and its material co-doped with F and P. F and P are simultaneously precipitated and can be uniformly dispersed in the precursor to achieve uniform doping. By utilizing the synergistic doping effect of F and P, the electrochemical performance and cycle stability of the lithium-rich material are effectively improved.

[0033] 2. This invention provides a technique for synergistic regulation of the morphology and arrangement of primary lithium-rich material precursors by F and P, synthesizing lithium-rich material precursors with radially oriented needle-like morphology, which is beneficial for the rapid migration of lithium ions from the interior to the surface of the material, and effectively solves the stress problem of lithium-rich materials during cycling.

[0034] 3. This invention provides a method for co-doping with F and P, in which doping elements are added simultaneously during the precursor synthesis process. The process is simple, easy to operate, and low in cost, resulting in good economic benefits and facilitating large-scale industrialization.

[0035] The present invention has been described in detail above; however, the above embodiments are merely illustrative in nature and are not intended to limit the invention. Furthermore, this document is not limited to the foregoing prior art or the invention itself, or to any theory described in the following embodiments. Attached Figure Description

[0036] Figure 1 This is a schematic diagram showing the diameter and aspect ratio of a primary particle;

[0037] Figure 2 Here is a SEM image of the precursor from Example 1;

[0038] Figure 3 This is a distribution diagram of the precursor EDS from Example 1;

[0039] Figure 4 Here is a SEM image of the precursor from Example 4;

[0040] Figure 5 This is a diagram showing the EDS distribution of the precursor in Example 4;

[0041] Figure 6 The image shows the precursor SEM image for Comparative Example 1.

[0042] Figure 7 The image shows the precursor SEM image for Comparative Example 2.

[0043] Figure 8 The image shows the precursor SEM image for Comparative Example 3.

[0044] Figure 9 The image shown is a SEM image of the precursor in Comparative Example 4. Detailed Implementation

[0045] The present invention will be further described below with reference to the embodiments. It should be noted that the following embodiments are provided for illustrative purposes only and do not constitute a limitation on the scope of protection of the present invention.

[0046] Unless otherwise specified, the raw materials, reagents, and methods used in the embodiments are all conventional raw materials, reagents, and methods in the art.

[0047] Example 1

[0048] (1) Manganese sulfate, nickel sulfate, and cobalt sulfate were weighed and dissolved in deionized water according to a molar ratio of Mn:Ni:Co of 0.65:0.30:0.05 to prepare a 2 mol / L mixed salt solution. A 4 mol / L NaOH solution containing 0.010 mol / L NH4F and 0.010 mol / L (NH4)2HPO3 was prepared as a precipitant, and a 1 mol / L ammonia solution was prepared as a complexing agent. The reaction solutions were mixed to carry out precipitation. The reaction temperature was controlled at 50℃, the pH at 11, and the stirring speed at 800 rpm. After the reaction was completed, the solution was washed, filtered, and dried to obtain Mn doped with 0.5% F and 0.5% P (molar percentage). 0.65 Ni 0.30 Co 0.05 (OH)₂ precursor. Its SEM image is shown below. Figure 2 As shown, the precursor is spherical, the primary particles are needle-shaped and arranged radially. The length of the primary particles is 100-250 nm, the diameter is 15-45 nm, and the aspect ratio is 4-10.

[0049] EDS distribution map as follows Figure 3 As shown, the dopant elements F and P are uniformly distributed in the precursor. According to the EDS results, their molar percentages with the transition metal are 0.47% and 0.49%, respectively, which are basically consistent with the amount added.

[0050] (2) The precursor and lithium carbonate (calculated as Li) were mixed at a molar ratio of 1:1.4 of total metal to Li. The mixture was kept at 500°C for 4 hours in air atmosphere, then kept at 900°C for 12 hours, and naturally cooled to room temperature to obtain FP-doped lithium-rich manganese-based material.

[0051] Example 2

[0052] (1) Manganese sulfate, nickel sulfate, and cobalt sulfate were weighed and dissolved in deionized water according to a molar ratio of Mn:Ni:Co of 0.55:0.25:0.2 to prepare a 2 mol / L mixed salt solution. A 4 mol / L NaOH solution containing 0.006 mol / L NH4F and 0.014 mol / L (NH4)2HPO3 was prepared as a precipitant, and a 1 mol / L ammonia solution was prepared as a complexing agent. The reaction solutions were mixed to carry out precipitation. The reaction temperature was controlled at 50℃, the pH at 10.5, and the stirring speed at 600 rpm. After the reaction was completed, the solution was washed, filtered, and dried to obtain Mn doped with 0.3% F and 0.7% P. 0.55 Ni 0.25 Co 0.2 (OH)2 precursor.

[0053] (2) The precursor and lithium carbonate (calculated as Li) were mixed at a molar ratio of 1:1.1 of total metal to Li. The mixture was kept at 500°C for 4 hours in air atmosphere, then kept at 800°C for 12 hours, and naturally cooled to room temperature to obtain FP-doped lithium-rich manganese-based material.

[0054] Example 3

[0055] (1) Manganese sulfate and nickel sulfate were weighed and dissolved in deionized water at a molar ratio of Mn:Ni of 0.80:0.20 to prepare a 2 mol / L mixed salt solution. A 4 mol / L NaOH solution containing 0.004 mol / L NH4F and 0.006 mol / L (NH4)2HPO3 was prepared as a precipitant, and a 1 mol / L ammonia solution was prepared as a complexing agent. The reaction solutions were mixed to carry out precipitation. The reaction temperature was controlled at 50℃, the pH at 10, and the stirring speed at 900 rpm. After the reaction was completed, the solution was washed, filtered, and dried to obtain Mn doped with 0.2% F and 0.3% P. 0.8 Ni 0.20 (OH)2 precursor.

[0056] (2) The precursor and lithium carbonate (calculated as Li) were mixed at a molar ratio of 1:1.6 of total metal to Li. The mixture was kept at 600°C for 4 hours in air atmosphere, then kept at 1000°C for 12 hours, and naturally cooled to room temperature to obtain FP-doped lithium-rich manganese-based material.

[0057] Example 4

[0058] (1) Manganese sulfate, nickel sulfate, and cobalt sulfate were weighed and dissolved in deionized water according to a molar ratio of Mn:Ni:Co of 0.6:0.30:0.1 to prepare a 2 mol / L mixed salt solution. A 4 mol / L NaOH solution containing 0.008 mol / L NH4F and 0.012 mol / L (NH4)2HPO3 was prepared as a precipitant, and a 1 mol / L ammonia solution was prepared as a complexing agent. The reaction solutions were mixed to carry out precipitation. The reaction temperature was controlled at 50℃, the pH at 11, and the stirring speed at 800 rpm. After the reaction was completed, the solution was washed, filtered, and dried to obtain Mn doped with 0.4% F and 0.6% P. 0.6 Ni 0.30 Co 0.1 (OH)₂ precursor. SEM images show... Figure 4 As shown, the precursor is spherical, and the primary particles are also needle-shaped and arranged radially. The length of the primary particles is 120-300 nm, the diameter is 30-80 nm, and the aspect ratio is 3.5-7.

[0059] EDS such as Figure 5 As shown, the doping elements F and P are uniformly distributed in the precursor. According to the EDS results, their molar percentages with the transition metal are 0.38% and 0.57%, respectively, which are basically consistent with the amount added.

[0060] (2) The precursor and lithium carbonate (calculated as Li) were mixed at a molar ratio of 1:1.35 of total metal to Li. The mixture was kept at 500°C for 4 hours in air atmosphere, then kept at 800°C for 12 hours, and naturally cooled to room temperature to obtain FP-doped lithium-rich manganese-based material.

[0061] Example 5

[0062] (1) Manganese sulfate, nickel sulfate, and cobalt sulfate were weighed and dissolved in deionized water according to a molar ratio of Mn:Ni:Co of 0.7:0.20:0.1 to prepare a 2 mol / L mixed salt solution. A 4 mol / L NaOH solution containing 0.004 mol / L NH4F and 0.016 mol / L (NH4)2HPO3 was prepared as a precipitant, and a 1 mol / L ammonia solution was prepared as a complexing agent. The reaction solutions were mixed to carry out precipitation. The reaction temperature was controlled at 50℃, the pH at 12, and the stirring speed at 700 rpm. After the reaction was completed, the solution was washed, filtered, and dried to obtain Mn doped with 0.2% F and 0.8% P. 0.7 Ni 0.20 Co 0.1 (OH)2 precursor.

[0063] (2) The precursor and lithium carbonate (calculated as Li) were mixed at a molar ratio of 1:1.5 of total metal to Li. The mixture was kept at 500°C for 4 hours in air atmosphere, then kept at 950°C for 12 hours, and naturally cooled to room temperature to obtain FP-doped lithium-rich manganese-based material.

[0064] Comparative Example 1

[0065] (1) Manganese sulfate, nickel sulfate, and cobalt sulfate were weighed according to a molar ratio of Mn:Ni:Co of 0.65:0.30:0.05 and dissolved in deionized water to prepare a 2 mol / L mixed salt solution. A 4 mol / L NaOH solution was prepared as a precipitant, and a 1 mol / L ammonia solution was prepared as a complexing agent. The reaction solutions were mixed to precipitate the mixture. The reaction temperature was controlled at 50℃, the pH at 11, and the stirring speed at 800 rpm. After the reaction was completed, the mixture was washed, filtered, and dried to obtain Mn. 0.65 Ni 0.30 Co 0.05 (OH)₂ precursor. SEM images show... Figure 6 As shown, the precursor is a porous, spherical structure composed of polygonal sheet-like primary particles with varying lengths and thicknesses. The length of the primary particles ranges from 200 to 600 nm, and the thickness ranges from 30 to 150 nm.

[0066] (2) The precursor and lithium carbonate (calculated as Li) were mixed at a molar ratio of 1:1.4 of total metal to Li. The mixture was kept at 500°C for 4 hours in air atmosphere, then kept at 900°C for 12 hours, and naturally cooled to room temperature to obtain lithium-rich manganese-based material.

[0067] Comparative Example 2

[0068] (1) Manganese sulfate, nickel sulfate, and cobalt sulfate were weighed according to a molar ratio of Mn:Ni:0.30:0.05 and dissolved in deionized water to prepare a 2 mol / L mixed salt solution. A 4 mol / L NaOH solution containing 0.010 mol / L NH4F was prepared as a precipitant, and a 1 mol / L ammonia solution was prepared as a complexing agent. The reaction solutions were mixed to carry out precipitation. The reaction temperature was controlled at 50℃, the pH at 11, and the stirring speed at 800 rpm. After the reaction was completed, the solution was washed, filtered, and dried to obtain Mn doped with 0.5% F. 0.65 Ni 0.30 Co 0.05 (OH)₂ precursor. SEM image as follows. Figure 7 It can be seen that the precursor is similar to Comparative Example 1, being a loose and porous spherical shape, composed of polygonal plate-like primary particles with different lengths and thicknesses. The length of the primary particles is relatively wide, ranging from 200 to 1400 nm, and the thickness ranges from 30 to 180 nm.

[0069] (2) The precursor and lithium carbonate (calculated as Li) were mixed at a molar ratio of 1:1.4 of total metal to Li. The mixture was kept at 500°C for 4 hours in air atmosphere, then kept at 900°C for 12 hours, and naturally cooled to room temperature to obtain F-doped lithium-rich manganese-based material.

[0070] Comparative Example 3

[0071] (1) Manganese sulfate, nickel sulfate, and cobalt sulfate were weighed and dissolved in deionized water according to a molar ratio of Mn:Ni:0.30:0.05 to prepare a 2 mol / L mixed salt solution. A 4 mol / L NaOH solution containing 0.010 mol / L (NH4)2HPO3 was prepared as a precipitant, and a 1 mol / L ammonia solution was prepared as a complexing agent. The reaction solutions were mixed to carry out precipitation. The reaction temperature was controlled at 50℃, the pH at 11, and the stirring speed at 800 rpm. After the reaction was completed, the solution was washed, filtered, and dried to obtain Mn doped with 0.5% P. 0.65 Ni 0.30 Co 0.05 (OH)₂ precursor. SEM image as follows. Figure 8 It can be seen that the precursor is similar to that of Comparative Example 1, and is a spherical shape composed of plate-like or block-like polygonal primary particles. The length and thickness of the primary particles have a wide distribution range, with a length range of 400-1500 nm and a thickness range of 50-450 nm.

[0072] (2) The precursor and lithium carbonate (calculated as Li) were mixed at a molar ratio of 1:1.4 of total metal to Li. The mixture was kept at 500°C for 4 hours in air atmosphere, then kept at 900°C for 12 hours, and naturally cooled to room temperature to obtain P-doped lithium-rich manganese-based material.

[0073] Comparative Example 4

[0074] (1) Manganese sulfate, nickel sulfate, and cobalt sulfate were weighed according to a molar ratio of Mn, Ni, and Co of 0.65:0.30:0.05 and dissolved in deionized water to prepare a 2 mol / L mixed salt solution. A 4 mol / L NaOH solution containing 0.010 mol / L Na2FPO3 was prepared as a precipitant, and a 1 mol / L ammonia solution was prepared as a complexing agent. The reaction solutions were mixed for precipitation, and the reaction temperature was controlled at 50℃, pH at 11, and stirring speed at 800 rpm. After the reaction was completed, the mixture was washed, filtered, and dried to obtain Mn doped with 0.5% F and 0.5% P. 0.65 Ni 0.30 Co 0.05 (OH)₂ precursor. SEM image as follows. Figure 9 It can be seen that the secondary particles of the precursor are also spherical, while the primary particles are arranged in a non-radial manner, resembling a loose fibrous morphology.

[0075] (2) The precursor and lithium carbonate (calculated as Li) were mixed at a molar ratio of 1:1.4 of total metal to Li. The mixture was kept at 500°C for 4 hours in air atmosphere, then kept at 900°C for 12 hours, and naturally cooled to room temperature to obtain F and P doped lithium-rich manganese-based materials.

[0076] The positive electrode active material, acetylene black, polyvinylidene fluoride and N-methylpyrrolidone of the above examples and comparative examples were mixed to form a slurry, which was uniformly coated on the surface of an aluminum foil to obtain a positive electrode sheet; then, a lithium sheet was used as the negative electrode sheet, and a 1 mol / L lithium hexafluorophosphate ethylene carbonate (EC) and dimethyl carbonate (DMC) solution (EC to DMC volume ratio of 1:1) was used as the electrolyte. The assembly was carried out in a glove box to obtain a lithium-ion battery.

[0077] The cycle performance of lithium-ion batteries was tested using an electrochemical testing instrument at a temperature of 25°C and at current densities of 0.1C, 1C, and 3C (1C = 200 mAg). -1 The charge / discharge voltage range is 4.6–2.0V. The initial charge / discharge performance, 1C and 3C rate performance of the battery are tested. Cycle performance is tested at 2.0–4.4V, 1C / 1C.

[0078] The results are shown in Table 1.

[0079] Table 1. Results of Button Battery Performance Test

[0080]

[0081]

[0082] The above embodiments are merely illustrative of the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein, without departing from the spirit and substance defined by the claims of the present invention; and such modifications or substitutions are still within the scope defined by the claims of the present invention.

Claims

1. A lithium-rich manganese-based precursor, characterized in that, The lithium-rich manganese-based precursor is a nickel-manganese hydroxide or a nickel-cobalt-manganese hydroxide doped with fluorine and phosphorus elements. The lithium-rich manganese-based precursor is composed of secondary spherical or near-spherical particles made up of primary particles. The primary particles have a needle-like morphology and are arranged radially along the secondary particles. The diameter of the primary particles is 10~100nm, and the aspect ratio of the primary particles is ≥3; The molar ratio of manganese, nickel, and cobalt in the doped lithium-rich manganese-based precursor is 0.55~0.80:0.10~0.45:0~0.20; The molar ratio of fluorine to the total molar ratio of nickel, cobalt and manganese in the doped lithium-rich manganese-based precursor is 0.002~0.010:1; the molar ratio of phosphorus to the total molar ratio of nickel, cobalt and manganese is 0.003~0.010:

1. The preparation method of the doped lithium-rich manganese-based precursor includes the following steps: Soluble nickel salt, soluble manganese salt, and optionally soluble cobalt salt are dissolved in water to form a metal salt solution. Soluble fluoride and phosphate are dissolved in alkaline solution to form a precipitant solution. Under controlled reaction conditions, the metal salt solution, precipitant solution, and complexing agent are simultaneously added to the reaction vessel to form a precipitate. After filtration, washing, and drying, F and P doped lithium-rich manganese-based precursors are obtained. The concentration of the metal salt solution is 1-4 mol / L; The concentration of the alkaline solution is 1-4 mol / L; The complexing agent is ammonia solution with a concentration of 0.05-2 mol / L; The reaction conditions include: pH 10-12, temperature 40-60℃, and stirring speed 600-1000 r / min.

2. A method for preparing the lithium-rich manganese-based precursor according to claim 1, characterized in that, Includes the following steps: Soluble nickel salt, soluble manganese salt, and optionally soluble cobalt salt are dissolved in water to form a metal salt solution. Soluble fluoride and phosphate are dissolved in alkaline solution to form a precipitant solution. Under controlled reaction conditions, the metal salt solution, precipitant solution, and complexing agent are simultaneously added to the reaction vessel to form a precipitate. After filtration, washing, and drying, F and P doped lithium-rich manganese-based precursors are obtained. The concentration of the metal salt solution is 1-4 mol / L; The concentration of the alkaline solution is 1-4 mol / L; The complexing agent is ammonia solution with a concentration of 0.05-2 mol / L; The reaction conditions include: pH 10-12, temperature 40-60℃, and stirring speed 600-1000 r / min.

3. The preparation method according to claim 2, characterized in that, The soluble nickel salt includes any one or a combination of at least two of nickel sulfate, nickel acetate, nickel chloride, or nickel nitrate; the soluble manganese salt includes any one or a combination of at least two of manganese sulfate, manganese acetate, manganese chloride, or manganese nitrate; and the soluble cobalt salt includes any one or a combination of at least two of cobalt sulfate, cobalt acetate, cobalt chloride, or cobalt nitrate. Soluble fluorides include one or more of NH4F, NaF, and KF; soluble phosphates include one or more of (NH4)3PO3, (NH4)2HPO3, NH4H2PO3, Na3PO3, Na2HPO3, NaH2PO3, K3PO3, K2HPO3, and KH2PO3.

4. A positive electrode material, characterized in that, It is obtained by sintering a lithium-doped manganese-based precursor as described in claim 1 with a lithium source.

5. A battery, characterized in that, Includes the cathode material as described in claim 4.

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