Sodium-ion battery cathode material precursor and preparation method therefor, and sodium-ion battery cathode material, sodium-ion battery, and electric device

Abstract

A sodium-ion battery cathode material precursor and a preparation method therefor, and a sodium-ion battery cathode material, a sodium-ion battery, and an electric device. The sodium-ion battery cathode material precursor comprises a plurality of secondary particles, wherein a growth direction consistency coefficient U forming the secondary particles satisfies: U≥75% and U=(360-α) / 360*100%, α being an angle sum of all central angles which do not satisfy a specified condition; in the profile of each secondary particle, the central angle is a central angle that uses the center of a circle of the profile of the secondary particle as a vertex; and the specified condition is that in the profile, primary particles grow in a diameter direction of the profile in an intercalating manner on an outer layer of a sector area corresponding to the central angle. According to the provided sodium-ion battery cathode material precursor, primary particles have a good growth direction consistency, thereby facilitating the diffusion of sodium ions and also improving the material capacity and the rate capability.

Description

Sodium ion battery positive electrode material precursor and preparation method thereof, sodium ion battery positive electrode material, sodium ion battery and electrical equipment

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure claims priority to Chinese patent application number 202310954659.X filed with the Patent Office of China on July 31, 2023, entitled “Sodium ion battery positive electrode material precursor and preparation method thereof, sodium ion battery positive electrode material, sodium ion battery and electrical-related equipment,” the entire contents of which are incorporated by reference into this disclosure. Technical Field

[0003] The present disclosure relates to the field of sodium ion batteries, and in particular to a sodium ion battery positive electrode material precursor and a preparation method thereof, a sodium ion battery positive electrode material, a sodium ion battery, and electrical equipment. Background Art

[0004] The lack of lithium resources and high costs have restricted the application of lithium-ion batteries in large-scale energy storage. Sodium-ion batteries have the same working principle and similar battery components as lithium-ion batteries. They have a good industrial foundation and significant cost advantages, and have broad application space in new energy storage and low-speed transportation fields. At present, the positive electrode material is the decisive factor restricting the performance of sodium-ion batteries. The layered transition metal oxides in the positive electrode materials of sodium-ion batteries are a type of sodium-ion battery positive electrode material with high specific capacity, good stability and simple preparation methods. However, the commercialization of this type of material is still hindered by low energy density, relatively poor cycle life, and poor rate performance.

[0005] For layered oxide cathode materials, the physicochemical properties and morphological characteristics of the precursor directly influence the performance of the cathode material. Therefore, for sodium-ion battery cathode materials, the precursor is often required to have suitable physicochemical properties and morphological characteristics to increase the sodium ion insertion and extraction rate in the cathode material and shorten the sodium ion transport path, thereby ensuring the rate performance and capacity of the sodium-ion battery.

[0006] Summary of the Invention

[0007] The present disclosure provides a sodium ion battery positive electrode material precursor and a preparation method thereof, a sodium ion battery positive electrode material, a sodium ion battery and electrical-related equipment to solve the above-mentioned problems.

[0008] This disclosure adopts the following technical solutions:

[0009] A sodium ion battery cathode material precursor, comprising a plurality of secondary particles; a growth direction consistency coefficient U of primary particles constituting the secondary particles satisfies: U ≥ 75%, U = (360-α) / 360*100%;

[0010] Among them, α is the sum of the angles of all central angles that do not meet the specified conditions; the central angle is the central angle in the cross-section of the secondary particle with the center of the cross-section of the secondary particle as the vertex; the specified condition is: in the cross-section, in the outer layer of the fan-shaped area corresponding to the central angle, the primary particles grow by intercalation along the diameter direction of the cross-section.

[0011] Preferably, the sodium ion battery cathode material precursor meets one or more of the following conditions:

[0012] A. The growth direction consistency coefficient U of the primary particles satisfies: U ≥ 85%;

[0013] B. The primary particles are in the form of thin flakes, and the average thickness of the primary particles is 0.05-0.14 μm;

[0014] C. The average pore size of the secondary particles is 13-15.5 nm, and the average pore volume is 0.042-0.065 cm 3 / g.

[0015] Preferably, the sodium ion battery cathode material precursor meets one or more of the following conditions:

[0016] D. The particle size D50 of the precursor is 9.5-18 μm;

[0017] E. The tap density TD of the precursor is not less than 1.8 g / cm 3 ;

[0018] F. The specific surface area of ​​the precursor is 12-22m 2 / g;

[0019] G. The particle size distribution Span of the precursor is 0.3-0.6;

[0020] H. the half maximum width (FWHM) (100) of the precursor is 0.38-0.58°;

[0021] Preferably, the chemical formula of the sodium ion battery cathode material precursor is Ni x Mn y Fe 1-x-y-z Me z (OH)2, wherein 0.15≤x≤0.4, 0.2≤y≤0.5, 0≤z≤0.04; Me is selected from one or more of Zn, Ti, Mg, Al, Zr, and Ca.

[0022] The present disclosure also provides a method for preparing a precursor of a positive electrode material for a sodium ion battery, comprising:

[0023] Mixing materials including a complexing agent, a precipitant, and water to obtain a base solution;

[0024] The target mixed metal salt solution, the precipitant, and the complexing agent are added to the base liquid in parallel, and under an inert gas atmosphere, the pH value of the reaction system, the reaction stirring rate, and the flow rate of the target mixed metal salt solution are controlled to perform a coprecipitation reaction to obtain the sodium ion battery positive electrode material precursor;

[0025] The mother liquor is continuously discharged during the coprecipitation reaction.

[0026] Preferably, the method for preparing the sodium ion battery cathode material precursor satisfies one or more of the following conditions:

[0027] The pH value of the reaction system is 10-11;

[0028] Preferably, the pH value of the reaction system is 10.4 to 11.0;

[0029] b. During the coprecipitation reaction, the stirring rate is reduced by 10-100 r / min / times every 4-8 h until it is reduced to the minimum stirring rate; preferably, the minimum stirring rate setting principle is: when D50≤11 μm, the minimum stirring rate is 120 r / min; when 11 μm≤D50≤13 μm, the minimum stirring rate is 110 r / min; when 13 μm≤D50≤15 μm, the minimum stirring rate is 100 r / min; when 15 μm≤D50≤18 μm, the minimum stirring rate is 90 r / min;

[0030] c. During the coprecipitation reaction, the flow rate of the target mixed metal salt solution is increased by 1.5-3 times the previous flow rate for every 2-4 μm increase in the particle size D50 of the particles obtained by the reaction, until the maximum flow rate is reached; the maximum flow rate is not higher than 8% / h of the volume of the reaction vessel;

[0031] Preferably, the maximum flow rate is 6% / h to 8% / h of the volume of the reaction vessel;

[0032] c '. The coprecipitation reaction temperature is 42 to 60 ° C;

[0033] c". The complexing agent is ammonia water, and the ammonia concentration in the base liquid is 3.0-4.2 g / L.

[0034] Preferably, the method for preparing the sodium ion battery cathode material precursor satisfies one or more of the following conditions:

[0035] d. The target mixed metal salt solution includes nickel salts, manganese salts, ferrous salts and Me salts; Me is selected from one or more of Zn, Ti, Mg, Al, Zr, and Ca;

[0036] e. After the coprecipitation reaction is completed, the process further comprises: solid-liquid separation to obtain a solid, followed by alkali washing, water washing, and drying to obtain the sodium ion battery cathode material precursor.

[0037] The present disclosure also provides a sodium ion battery positive electrode material, the raw materials of which include the sodium ion battery positive electrode material precursor.

[0038] The present disclosure also provides a method for preparing a positive electrode material for a sodium ion battery, comprising:

[0039] A sodium ion battery positive electrode material precursor and a sodium source are mixed and calcined to obtain the sodium ion battery positive electrode material.

[0040] Preferably, the preparation method of the sodium ion battery positive electrode material meets one or more of the following conditions:

[0041] f. The calcination was performed at a heating rate of 2-4 ° C / min to 780-880 ° C for 10-20h;

[0042] g. The ratio of the sum of the molar amounts of all metal elements in the sodium ion battery positive electrode material precursor to the molar amount of sodium in the sodium source is 1:(1.02-1.07).

[0043] The present disclosure also provides a sodium ion battery, the raw materials of which include the sodium ion battery positive electrode material.

[0044] The present disclosure also provides an electrical device, comprising the sodium ion battery.

[0045] Compared with the prior art, the advantages of the present invention include:

[0046] The sodium ion battery cathode material precursor provided by the present disclosure includes multiple secondary particles. The primary particles constituting the secondary particles intercalate and grow along the diameter direction of the secondary particles with high consistency in the growth direction, which is beneficial to the transmission and deintercalation of sodium ions, thereby improving the rate performance of the sodium ion battery prepared by the corresponding cathode material.

[0047] The sodium ion battery positive electrode material, sodium ion battery and electrical equipment provided by the present disclosure have excellent electrical performance.

[0048] The present disclosure provides a method for preparing a sodium ion battery cathode material precursor. Through a coprecipitation process, under inert gas atmosphere conditions, the pH value of the reaction system, the stirring rate, and the flow rate of the target mixed metal salt solution are controlled to obtain a sodium ion battery cathode material precursor with good consistency in the primary particle growth direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope of the present disclosure.

[0050] FIG1 is a scanning electron microscope image of the nickel-iron-manganese precursor of Example 1;

[0051] FIG2 is an electron microscope image of a local surface of the nickel-iron-manganese precursor of Example 1;

[0052] FIG3 is a cross-sectional electron micrograph of the nickel-iron-manganese precursor of Example 1;

[0053] FIG4 is a scanning electron microscope image of the nickel-iron-manganese precursor of Example 2;

[0054] FIG5 is a cross-sectional electron micrograph of the nickel-iron-manganese precursor of Example 2;

[0055] FIG6 is a cross-sectional electron micrograph of the nickel-iron-manganese-magnesium precursor of Example 3;

[0056] FIG7 is a cross-sectional electron micrograph of the nickel-iron-manganese-zinc precursor of Example 4;

[0057] FIG8 is a scanning electron microscope image of the nickel-iron-manganese precursor of Comparative Example 1;

[0058] FIG9 is an electron microscope image of a local surface of the nickel-iron-manganese precursor of Comparative Example 1;

[0059] FIG10 is a cross-sectional electron micrograph of the nickel-iron-manganese precursor of Comparative Example 1;

[0060] FIG11 is a scanning electron microscope image of the nickel-iron-manganese precursor of Comparative Example 2;

[0061] FIG12 is a cross-sectional electron microscope image of the nickel-iron-manganese precursor of Comparative Example 2. DETAILED DESCRIPTION

[0062] As used herein:

[0063] "Prepared from" is synonymous with "comprising." As used herein, the terms "comprising," "including," "having," "containing," or any other variations thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises the listed elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0064] The conjunction "consisting of" excludes any unspecified element, step, or component. If used in a claim, this phrase renders the claim closed, excluding materials other than those described, except for conventional impurities associated therewith. When the phrase "consisting of" appears in a clause of the body of a claim, rather than immediately following the subject matter, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.

[0065] When an amount, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper preferred values ​​and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pairing of any range upper limit or preferred value with any range lower limit or preferred value, regardless of whether the range is disclosed alone. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted as including the range "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5", etc. When a numerical range is described herein, unless otherwise stated, the range is intended to include its end values ​​and all integers and fractions within the range.

[0066] In these examples, parts and percentages are by mass unless otherwise indicated.

[0067] "And / or" is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0068] "At least one" means one or more, and "a plurality" means two or more.

[0069] A sodium ion battery positive electrode material precursor, comprising a plurality of secondary particles, wherein a growth direction consistency coefficient U of primary particles constituting the secondary particles satisfies: U≥75%, U=(360-α) / 360*100%;

[0070] Among them, α is the sum of the angles of all central angles that do not meet the specified conditions; the central angle is the central angle in the cross-section of the secondary particle with the center of the cross-section of the secondary particle as the vertex; the specified condition is: in the cross-section, in the outer layer of the fan-shaped area corresponding to the central angle, the primary particle grows by intercalation along the diameter direction of the cross-section.

[0071] It should be understood that the secondary particles of the positive electrode material precursor in the present disclosure are spherical or quasi-spherical, and the cross-section refers to the surface cut through the center of the secondary particle in the diameter direction (when there is a deviation in the actual test, the surface cut through the secondary particle close to the center of the sphere can also be a cross-section); the intercalation growth of the primary particle in the diameter direction of the cross-section includes both the case where the angle between the primary particle growth direction and the diameter direction is 0°, and the case where the angle formed between the primary particle growth direction and the diameter direction is within 30°. When the secondary particle is spherical, the center of the cross-section is used as the center for measurement when calculating the consistency coefficient U; when the secondary particle is quasi-spherical, the center position between the two farthest points on the outermost boundary of the cross-section can be selected as the center for measurement. Since the consistency coefficient U is manually measured, when the arrangement of some primary particles is difficult to identify, it is not counted as not meeting the specified conditions; in addition, when the primary particles are densely arranged and have no pores, it is difficult to directly identify their arrangement direction in the cross-sectional view, and it is counted as intercalation growth along the diameter direction. The growth direction consistency coefficient U of the primary particles is greater than or equal to 75%, and the number of secondary particles in the precursor accounts for ≥60%.

[0072] In an optional embodiment, the sodium ion battery cathode material precursor meets one or more of the following conditions:

[0073] A. The growth direction consistency coefficient U of the primary particles satisfies: U ≥ 85%;

[0074] B. The primary particles are in the form of thin flakes, and the thickness of the primary particles is 0.05-0.14 μm;

[0075] The primary particles are in the form of thin flakes, which can increase the specific surface area of ​​the precursor and increase the contact area between the corresponding positive electrode material and the electrolyte, thereby improving the charge and discharge capacity and rate performance of the corresponding sodium ion battery; optionally, the thickness of the primary particles can be 0.05 μm, 0.06 μm, 0.07 μm, 0.08 μm, 0.09 μm, 0.10 μm, 0.11 μm, 0.12 μm, 0.13 μm, 0.14 μm or any value between 0.05 and 0.14 μm;

[0076] C. The average pore size of the secondary particles is 13-15.5 nm, and the average pore volume is 0.042-0.065 cm 3 / g.

[0077] The loose, porous and evenly distributed pores provide a permeation path for the electrolyte, greatly improving the penetration efficiency of the electrolyte, which is conducive to the rapid penetration of the electrolyte into the internal structure of the material, improving the battery capacity and rate performance; it can also alleviate the volume changes caused by the insertion and extraction of sodium ions during charging and discharging, and improve the service life of the battery.

[0078] The average pore size and average pore volume of the secondary particles in each range (0-9 μm, 0-13.7 μm, 0-13.9 μm, 0-18 μm) along the radial direction are all within the above ranges, which shows that the pores of the secondary particles are relatively uniform.

[0079] Optionally, the average pore size of the secondary particles may be 13 nm, 13.5 nm, 14 nm, 14.5 nm, 15 nm, 15.5 nm or any value between 13 and 15.5 nm, and the average pore volume may be 0.042 cm 3 / g, 0.045cm 3 / g, 0.050cm 3 / g, 0.055cm 3 / g, 0.060cm 3 / g, 0.065cm 3 / g or 0.042-0.065cm 3 Any value between / g.

[0080] In an optional embodiment, the sodium ion battery cathode material precursor meets one or more of the following conditions:

[0081] D. The particle size D50 of the precursor is 9.5-18 μm;

[0082] The secondary particles of the precursor are generally spherical or spherical, and the precursor has a relatively large particle size, which is beneficial to increasing the tap density of the corresponding positive electrode material and improving the battery energy density.

[0083] Optionally, the particle size D50 of the precursor may be 9.5 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, or any value between 9.5 and 18 μm;

[0084] E. The tap density TD of the precursor is not less than 1.8 g / cm 3 ;

[0085] Optionally, the tap density TD of the precursor is 1.8-2.2 g / cm 3 or 1.8-2.5g / cm 3 ;

[0086] Optionally, the tap density TD of the precursor may be 1.8 g / cm 3 , 1.9g / cm 3 , 2.0g / cm 3 , 2.1g / cm 3 , 2.2g / cm 3 , 2.3g / cm 3 , 2.4g / cm3 , 2.5g / cm 3 , 2.6g / cm 3 , 2.7g / cm 3 , 2.8g / cm 3 , 2.9g / cm 3 , 3.0g / cm 3 or not less than 1.8g / cm 3 Any value of

[0087] The precursor has a high tap density, which can increase the volume energy density of the material, so that the corresponding battery has high discharge capacity and high charge and discharge efficiency;

[0088] F. The specific surface area of ​​the precursor is 12-22m 2 / g;

[0089] Optionally, the BET surface area of ​​the precursor can be 12 m 2 / g、13m 2 / g、14m 2 / g、15m 2 / g、16m 2 / g、17m 2 / g、18m 2 / g、19m 2 / g, 20m 2 / g、21m 2 / g、22m 2 / g or 12-22m 2 Any value between / g;

[0090] G. The particle size distribution Span of the precursor is 0.3-0.6;

[0091] The smaller the Span value of the precursor, the more uniform the size of the secondary particles of the precursor. When used in the positive electrode, it can be filled more densely, which can improve the discharge capacity of the battery.

[0092] Optionally, the particle size distribution Span of the precursor may be 0.3, 0.4, 0.5, 0.6 or any value between 0.3 and 0.6;

[0093] H. the half maximum width (FWHM) (100) of the precursor is 0.38-0.58°;

[0094] The precursor has a narrow half-peak width and a high crystallinity, which can improve the corresponding cycle performance.

[0095] Optionally, the half maximum width FWHM (100) of the precursor may be 0.38°, 0.40°, 0.45°, 0.50°, 0.55°, 0.58° or any value between 0.38-0.58°;

[0096] In an optional embodiment, the chemical formula of the sodium ion battery cathode material precursor is Ni x Mn y Fe 1-x-y-z Me z (OH)2, wherein 0.15≤x≤0.4, 0.2≤y≤0.5, 0≤z≤0.04; Me is selected from one or more of Zn, Ti, Mg, Al, Zr, and Ca.

[0097] Optionally, x can be 0.15, 0.16, 0.17, 0.18, 0.19, 0.20, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.30, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.40 or any value between 0.15 and 0.4, and y can be 0.20, 0.21, 0.22, 0.23, 0.24, 0 0.25, 0.26, 0.27, 0.28, 0.29, 0.30, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.40, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, 0.50 or any value between 0.2 and 0.5, and z can be 0, 0.01, 0.02, 0.03, 0.04 or any value between 0 and 0.04.

[0098] The present disclosure also provides a method for preparing a precursor of a positive electrode material for a sodium ion battery, comprising:

[0099] Mixing materials including a complexing agent, a precipitant, and water to obtain a base solution;

[0100] Adding the target mixed metal salt solution, the precipitant, and the complexing agent to the base solution, and performing a coprecipitation reaction under an inert gas atmosphere while controlling the pH value of the reaction system, the reaction stirring rate, and the flow rate of the target mixed metal salt solution to obtain the sodium ion battery positive electrode material precursor;

[0101] The mother liquor is continuously discharged during the coprecipitation reaction.

[0102] In an optional embodiment, the method for preparing the sodium ion battery positive electrode material precursor satisfies one or more of the following conditions:

[0103] The pH value of the reaction system is 10-11;

[0104] Optionally, the pH value of the reaction system can be 10, 10.1, 10.2, 10.3, 10.4, 10.5, 10.6, 10.7, 10.8, 10.9, 11 or any value between 10-11;

[0105] Preferably, the pH value of the reaction system is 10.4 to 11.0;

[0106] b. During the coprecipitation reaction, the stirring rate is reduced by 10-100 r / min / times every 4-8h until it is reduced to the minimum stirring rate; preferably, the minimum stirring rate setting principle is: when D50≤11μm, the minimum stirring rate is 120r / min; when 11μm≤D50≤13μm, the minimum stirring rate is 110r / min; when 13μm≤D50≤15μm, the minimum stirring rate is 100r / min; when 15μm≤D50≤18μm, the minimum stirring rate is 90r / min;

[0107] Optionally, the time interval may be 4 h, 5 h, 6 h, 7 h, 8 h or any value between 4 and 8 h, and the value of reducing the stirring rate may be 10 r / min / time, 20 r / min / time, 30 r / min / time, 40 r / min / time, 50 r / min / time, 60 r / min / time, 70 r / min / time, 80 r / min / time, 90 r / min / time, 100 r / min / time or any value between 10 and 100 r / min / time;

[0108] c. During the coprecipitation reaction, the flow rate of the target mixed metal salt solution is increased by 1.5-3 times the previous flow rate for every 2-4 μm increase in the particle size D50 of the particles obtained by the reaction, until the maximum flow rate is reached; the maximum flow rate is not higher than 8% / h of the reaction vessel volume;

[0109] Preferably, the maximum flow rate is 6% / h-8% / h of the reaction vessel volume;

[0110] c '. The coprecipitation reaction temperature is 42 to 60 ° C; optionally, the coprecipitation reaction temperature may be 42 ° C, 43 ° C, 44 ° C, 45 ° C, 46 ° C, 47 ° C, 48 ° C, 49 ° C, 50 ° C, 51 ° C, 52 ° C, 53 ° C, 54 ° C, 55 ° C, 57 ° C, 58 ° C, 59 ° C, 60 ° C or any value between 42 ° C-60 ° C;

[0111] c". The complexing agent is aqueous ammonia, and the ammonia concentration in the base liquid is 3.0 to 4.2 g / L; optionally, the ammonia concentration in the base liquid can be 3.0 g / L, 3.2 g / L, 3.4 g / L, 3.5 g / L, 3.6 g / L, 3.8 g / L, 4.0 g / L, 4.2 g / L, or any value between 3.0 and 4.2 g / L.

[0112] In an optional embodiment, the method for preparing the sodium ion battery positive electrode material precursor satisfies one or more of the following conditions:

[0113] d. The target mixed metal salt solution includes nickel salts, manganese salts, ferrous salts and Me salts; Me is selected from one or more of Zn, Ti, Mg, Al, Zr, and Ca;

[0114] e. After the coprecipitation reaction is completed, the process further comprises: solid-liquid separation to obtain a solid, followed by alkali washing, water washing, and drying to obtain the sodium ion battery cathode material precursor.

[0115] The present disclosure also provides a sodium ion battery positive electrode material, the raw materials of which include the sodium ion battery positive electrode material precursor.

[0116] The present disclosure also provides a method for preparing a positive electrode material for a sodium ion battery, comprising:

[0117] A sodium ion battery positive electrode material precursor and a sodium source are mixed and calcined to obtain the sodium ion battery positive electrode material.

[0118] In an optional embodiment, the preparation method of the sodium ion battery positive electrode material meets one or more of the following conditions:

[0119] f. The calcination was performed at a heating rate of 2-4 ° C / min to 780-880 ° C for 10-20h;

[0120] Optionally, the heating rate may be 2°C / min, 3°C / min, 4°C / min, or any value between 2-4°C / min; the endpoint temperature may be 780°C, 790°C, 800°C, 810°C, 820°C, 830°C, 840°C, 850°C, 860°C, 870°C, 880°C, or any value between 780-880°C; and the calcination time may be 10h, 11h, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, or any value between 10-20h;

[0121] g. The ratio of the sum of the molar amounts of all metal elements in the sodium ion battery positive electrode material precursor to the molar amount of sodium in the sodium source is 1:(1.02-1.07).

[0122] Optionally, the ratio of the sum of the molar amounts of all metal elements in the sodium ion battery positive electrode material precursor to the molar amount of sodium in the sodium source can be 1:1.02, 1:1.03, 1:1.04, 1:1.05, 1:1.06, 1:1.07 or any value between 1:(1.02-1.07).

[0123] The present disclosure also provides a sodium ion battery, the raw materials of which include the sodium ion battery positive electrode material.

[0124] The present disclosure also provides an electrical device, comprising the sodium ion battery.

[0125] The embodiments of the present disclosure will be described in detail below with reference to specific examples. However, those skilled in the art will appreciate that the following examples are intended only to illustrate the present disclosure and should not be construed as limiting the scope of the present disclosure. Where specific conditions are not specified in the examples, conventional conditions or conditions recommended by the manufacturer were used. Reagents or instruments used where the manufacturer is not specified are conventional products that can be purchased commercially.

[0126] Example 1

[0127] This embodiment provides a sodium ion battery cathode material precursor, the preparation method of which is as follows:

[0128] Nickel, manganese, and ferrous sulfate crystals (molar ratio 1:1:1) were prepared into a 2 mol / L uniform metal salt mixed solution; 10 mol / L sodium hydroxide solution and 8 mol / L ammonia water were mixed to prepare a base solution with a pH of 11 and an ammonia concentration of 4 g / L; the base solution was added to a reactor with a stirring device, and the reaction temperature was set to 45°C at a stirring rate of 320 r / min, and then ammonia water, sodium hydroxide solution, and metal salt mixed solution were slowly added in a volume ratio of 1:8:20. The addition rate of the metal salt mixed solution is 2% / h of the volume of the reactor, the pH of the reaction system is controlled to be about 10.6, and the ammonia concentration is about 4g / L; the stirring speed of the reaction system is reduced by 20r / min every 5h, and remains unchanged after the speed drops to 100r / min; for every 3μm growth of the precursor, the flow rate of the metal salt mixed solution increases to 2 times the previous one, and when the flow rate of the metal salt mixed solution increases to 8% / h of the volume of the reactor, it no longer rises until the particle size of the reaction slurry reaches 13.7μm, and the feeding is stopped.

[0129] The precipitate was centrifuged and washed, alkaline washed with 0.5 mol / L sodium hydroxide solution, and then washed with 70°C deionized water. After centrifugal washing, the precipitate was dispersed, placed in a blast oven, dried and dehydrated at 120°C for 12 hours, and then taken out and sealed for storage.

[0130] The obtained dried material is crushed in a grinding device, and then sieved, demagnetized, and processed to obtain a nickel-iron-manganese ternary precursor. The molecular formula of the obtained sodium ion battery positive electrode material precursor is Ni 0.33 Mn 0.33 Fe 0.34 (OH)2.

[0131] Figure 1 is an electron micrograph of the precursor prepared in Example 1. The outer primary particles of the secondary particles of this precursor are thin sheets of relatively uniform size and have good growth direction consistency. To more intuitively represent the size of the primary particles, Figure 2 is an electron micrograph of a partial surface of the precursor prepared in Example 1. Five primary particles of representative size were selected from Figure 2 for measurement. The average thickness of the five primary particles was calculated to obtain an average thickness of 0.06 μm. Figure 3 is an electron micrograph of a cross-section of the precursor prepared in Example 1 (the angle in the figure is the degree of the central angle that does not meet the specified conditions; the specified conditions are: in the cross-section, in the outer layer of the fan-shaped area corresponding to the central angle, the primary particles grow intercalated along the diameter of the cross-section). It can be seen that the primary particles in the cross-section grow radially as a whole, forming a crown-like cross-section with a uniform pore distribution. The primary particles at the edge mainly grow intercalated along the diameter. The calculated primary particle growth direction consistency coefficient U = (360-20) / 360*100% = 94.4%. When the precursor grows to 9.0 μm, the pore volume is measured to be 0.0526 cm 3 / g, the average pore diameter is 14.3nm, and the pore volume is 0.0499cm when the precursor grows to 13.7μm. 3 / g, and the average pore diameter is 13.7nm, which is slightly different from the measured value at 9.0μm, indicating that the pore distribution is uniform and the pore size is consistent, which is consistent with the results of the cross-sectional electron microscopy image.

[0132] The obtained precursors were mixed according to the element molar ratio of (Ni+Mn+Fe):Na=1:1.05 and calcined at 830°C in a muffle furnace at a heating rate of 3°C / min for 15 hours. After cooling, they were crushed and sieved to make positive electrode sheets, which were then assembled with a diaphragm, sodium perchlorate electrolyte, and sodium sheet negative electrode into a button cell. The battery performance was tested between 2-4.2V, where the current size of 0.1C was 15mA / g.

[0133] Example 2

[0134] This embodiment provides a sodium ion battery cathode material precursor, and the specific steps are as follows:

[0135] Nickel, manganese, and ferrous sulfate crystals (molar ratio 28:36:36) were prepared into a 2 mol / L uniform metal salt mixed solution; 10 mol / L sodium hydroxide solution and 8 mol / L ammonia water were mixed to prepare a base solution with a pH of 11 and an ammonia concentration of 4 g / L; the base solution was added to a reactor with a stirring device, and the reaction temperature was set to 50°C at a stirring rate of 320 r / min, and then ammonia water, sodium hydroxide solution, and metal salt mixed solution were slowly added in a volume ratio of 1:8:20. The addition rate of the metal salt mixed solution is 2% / h of the volume of the reactor, the pH of the reaction system is controlled to be about 10.5, and the ammonia concentration is about 4g / L; the stirring speed of the reaction system is reduced by 20r / min every 5h, and remains unchanged after the speed drops to 100r / min; for every 3μm growth of the precursor, the flow rate of the metal salt mixed solution increases to 2 times the previous one, and when the flow rate of the metal salt mixed solution increases to 8% / h of the volume of the reactor, it no longer rises until the particle size of the reaction slurry reaches 13.9μm, and the feeding is stopped.

[0136] The precipitate was centrifuged and washed, alkaline washed with 0.5 mol / L sodium hydroxide solution, and then washed with 70°C deionized water. After centrifugal washing, the precipitate was dispersed, placed in a blast oven, dried and dehydrated at 120°C for 12 hours, and then taken out and sealed for storage.

[0137] The obtained dried material is crushed in a grinding device, and then sieved, demagnetized, and processed to obtain a nickel-iron-manganese ternary precursor. The molecular formula of the obtained sodium ion battery positive electrode material precursor is Ni 0.28 Mn 0.36 Fe 0.36 Figures 4 and 5 are surface electron micrographs and cross-sectional electron micrographs of the precursor prepared in Example 2 (Figure 5 shows the degree of the central angle that does not meet the specified conditions). It can be seen that Example 2 has a similar morphology and structure to Example 1.

[0138] The obtained precursors were mixed according to the element molar ratio of (Ni+Mn+Fe):Na=1:1.05 and calcined in a muffle furnace at a heating rate of 3°C / min to 830°C for 15 hours. After cooling, they were crushed and sieved, and then assembled into a battery. The battery performance was tested between 2-4.2V, using the same testing method as in Example 1.

[0139] Example 3

[0140] This embodiment provides a sodium ion battery cathode material precursor, and the specific steps are as follows:

[0141] Nickel, manganese, ferrous iron, and magnesium sulfate crystals (molar ratio 32:32:32:4) were prepared into a 2 mol / L uniform metal salt mixed solution; 10 mol / L sodium hydroxide solution and 8 mol / L ammonia water were mixed to prepare a base solution with a pH of 11 and an ammonia concentration of 4 g / L; the base solution was added to a reactor with a stirring device, and the reaction temperature was set to 60°C at a stirring rate of 360 r / min, and then ammonia water, sodium hydroxide solution, and metal sulfate were slowly added in a volume ratio of 1:8:20. The addition rate of the salt mixed solution and the metal salt mixed solution is 2% / h of the volume of the reactor, and the pH of the reaction system is controlled to be about 10.4 and the ammonia concentration is about 4g / L; the stirring speed of the reaction system is reduced by 30r / min every 5h, and remains unchanged after the speed is reduced to 100r / min; for every 3μm growth of the precursor, the flow rate of the metal salt mixed solution is increased to 2 times the previous one, and when the flow rate of the metal salt mixed solution increases to 6% / h of the volume of the reactor, it no longer rises until the particle size of the reaction slurry reaches 10μm, and the feeding is stopped.

[0142] The precipitate was centrifuged and washed, alkaline washed with 0.5 mol / L sodium hydroxide solution, and then washed with 70°C deionized water. After centrifugal washing, the precipitate was dispersed, placed in a blast oven, dried and dehydrated at 120°C for 12 hours, and then taken out and sealed for storage.

[0143] The obtained dried material is crushed in a grinding device, and then sieved, demagnetized, and processed to obtain a nickel-iron-manganese ternary precursor. The molecular formula of the obtained sodium ion battery positive electrode material precursor is Ni 0.32 Mn 0.32 Fe 0.32 Mg 0.04 FIG6 is a cross-sectional electron micrograph of the precursor prepared in Example 3 (FIG6 shows the degree of the central angle that does not meet the specified conditions). It can be seen that Example 3 has a similar morphology to Example 1.

[0144] The obtained precursors were mixed according to the element molar ratio of (Ni+Mn+Fe+Mg):Na=1:1.05 and calcined in a muffle furnace at a heating rate of 3°C / min to 830°C for 15 hours. After cooling, they were crushed and sieved, and then assembled into a battery. The battery performance was tested between 2-4.2V, using the same testing method as in Example 1.

[0145] Example 4

[0146] This embodiment provides a sodium ion battery cathode material precursor, and the specific steps are as follows:

[0147] Nickel, manganese, ferrous iron, and zinc sulfate crystals (molar ratio 32:33:33:2) were prepared into a 2 mol / L uniform metal salt mixed solution; 10 mol / L sodium hydroxide solution and 8 mol / L ammonia water were mixed to prepare a base solution with a pH of 11 and an ammonia concentration of 3 g / L; the base solution was added to a reactor with a stirring device, and the reaction temperature was set to 55°C at a stirring rate of 360 r / min, and then ammonia water, sodium hydroxide solution, and metal sulfate were slowly added in a volume ratio of 1:8:20. The addition rate of the salt mixed solution and the metal salt mixed solution is 2% / h of the volume of the reactor, and the pH of the reaction system is controlled to be about 10.4 and the ammonia concentration is about 3g / L; the stirring speed of the reaction system is reduced by 30r / min every 5h, and remains unchanged after the speed drops to 100r / min; for every 2μm growth of the precursor, the flow rate of the metal salt mixed solution increases to 2 times the previous one, and when the flow rate of the metal salt mixed solution increases to 6% / h of the volume of the reactor, it no longer rises until the particle size of the reaction slurry reaches 10μm, and the feeding is stopped.

[0148] The precipitate was centrifuged and washed, alkaline washed with 0.25 mol / L sodium hydroxide solution, and then washed with 70°C deionized water. After centrifugal washing, the precipitate was dispersed, placed in a blast oven, dried and dehydrated at 120°C for 12 hours, and then taken out and sealed for storage.

[0149] The obtained dried material is crushed in a grinding device, and then sieved, demagnetized, and processed to obtain a nickel-iron-manganese ternary precursor. The molecular formula of the obtained sodium ion battery positive electrode material precursor is Ni 0.32 Mn 0.33 Fe 0.33 Zn 0.02 FIG7 is a cross-sectional electron micrograph of the precursor prepared in Example 4 ( FIG7 shows the degree of the central angle of the circle that does not meet the specified conditions). It can be seen that Example 4 has a similar morphology and structure to Example 1.

[0150] The obtained precursors were mixed according to the element molar ratio of (Ni+Mn+Fe+Zn):Na=1:1.05 and calcined in a muffle furnace at a heating rate of 3°C / min to 830°C for 15 hours. After cooling, they were crushed and sieved, and then assembled into a battery. The battery performance was tested between 2-4.2V, using the same testing method as in Example 1.

[0151] Comparative Example 1

[0152] This comparative example provides a sodium ion battery positive electrode material precursor. Compared with Example 1, the growth direction consistency of the primary particles of the precursor is worse, the primary particles of the precursor are coarser, and the internal pores are less. The specific preparation steps are as follows:

[0153] Nickel, manganese, and ferrous sulfate crystals (molar ratio 1:1:1) were prepared into a 2 mol / L uniform metal salt mixed solution; 10 mol / L sodium hydroxide solution and 8 mol / L ammonia water were mixed to prepare a base solution with a pH of 11 and an ammonia concentration of 4 g / L; the base solution was added to a reactor with a stirring device, and the reaction temperature was set to 50°C at a stirring rate of 400 r / min. Then, ammonia water, sodium hydroxide solution, and metal salt mixed solution were slowly added in parallel at a volume ratio of 1:8:20. The addition rate of the metal salt mixed solution is 1% / h of the volume of the reactor, and the pH of the reaction system is controlled to be around 10.3 and the ammonia concentration is around 4.5g / L; the stirring speed of the reaction system is reduced by 20r / min every 4 hours, and remains unchanged after the speed drops to 120r / min; for every 2.5μm growth of the precursor, the flow rate of the metal salt mixed solution increases to 2 times the previous one, and when the flow rate of the metal salt mixed solution increases to 6% / h of the volume of the reactor, it no longer rises until the particle size of the reaction slurry reaches 10μm, and the feeding is stopped.

[0154] The precipitate was centrifuged and washed, alkaline washed with 0.5 mol / L sodium hydroxide solution, and then washed with 70°C deionized water. After centrifugal washing, the precipitate was dispersed, placed in a blast oven, dried and dehydrated at 120°C for 12 hours, and then taken out and sealed for storage.

[0155] The obtained dried material is crushed in a grinding device, and then sieved, demagnetized, and processed to obtain a nickel-iron-manganese ternary precursor. The molecular formula of the obtained sodium ion battery positive electrode material precursor is Ni 0.33 Mn 0.33 Fe 0.34 (OH)2. Figure 8 is an electron microscope image of the precursor prepared in Comparative Example 1, the outer primary particles of which are coarser than those in Example 1. Figure 9 is an electron microscope image of the local surface of the nickel-iron-manganese precursor in Comparative Example 1. Five primary particles with representative sizes were selected from Figure 9 for measurement, and the average thickness of the five primary particles was calculated to be 0.12 μm. Figure 10 is an electron microscope image of the cross-section of Comparative Example 1 (Figure 10 shows the degree of the central angle of the circle that does not meet the specified conditions). It can be seen that the interior is denser than that in Example 1, and the pore distribution is not as uniform as in Example 1.

[0156] The obtained precursors were mixed according to the element molar ratio of (Ni+Mn+Fe):Na=1:1.05 and calcined in a muffle furnace at a heating rate of 3°C / min to 830°C for 15 hours. After cooling, they were crushed and sieved, and then assembled into a battery. The battery performance was tested between 2-4.2V, using the same testing method as in Example 1.

[0157] Comparative Example 2

[0158] This comparative example provides a sodium ion battery positive electrode material precursor. Compared with Example 1, the primary particle growth direction consistency of the precursor is worse. The specific preparation steps are as follows:

[0159] Nickel, manganese, and ferrous sulfate crystals (molar ratio 1:1:1) were prepared into a 2 mol / L uniform metal salt mixed solution; 10 mol / L sodium hydroxide solution and 8 mol / L ammonia water were mixed to prepare a base solution with a pH of 11 and an ammonia concentration of 4 g / L; the base solution was added to a reactor with a stirring device, and the reaction temperature was set to 40°C at a stirring rate of 320 r / min, and then ammonia water, sodium hydroxide solution, and metal salt mixed solution were slowly added in a volume ratio of 1:8:20. The addition rate of the metal salt mixed solution is 2% / h of the volume of the reactor, the pH of the reaction system is controlled to be about 10.6, and the ammonia concentration is about 4g / L; the stirring speed of the reaction system is reduced by 20r / min every 5h, and remains unchanged after the speed drops to 100r / min; every time the precursor grows 2.5μm, the flow rate of the metal salt mixed solution increases to 2 times the previous one. When the flow rate of the metal salt mixed solution increases to 10% / h of the volume of the reactor, it no longer rises until the particle size of the reaction slurry reaches 14μm, and the feeding is stopped.

[0160] The precipitate was centrifuged and washed, alkaline washed with 0.5 mol / L sodium hydroxide solution, and then washed with 70°C deionized water. After centrifugal washing, the precipitate was dispersed, placed in a blast oven, dried and dehydrated at 120°C for 12 hours, and then taken out and sealed for storage.

[0161] The obtained dried material is crushed in a grinding device, and then sieved, demagnetized, and processed to obtain a nickel-iron-manganese ternary precursor. The molecular formula of the obtained sodium ion battery positive electrode material precursor is Ni 0.33 Mn 0.33 Fe 0.34 Figure 11 is an electron micrograph of the precursor prepared in Comparative Example 2. The primary particle growth direction consistency of this precursor is poor, with a large number of flattened fragments. Figure 12 is an electron micrograph of the cross-section of Comparative Example 2 (Figure 12 shows the degree of the central angle that does not meet the specified conditions). Based on this, the primary particle growth direction consistency coefficient U is calculated to be only 61.1%.

[0162] The positive electrode material and the corresponding battery were prepared according to the method of Comparative Example 1, and the battery performance test was carried out under the same conditions.

[0163] The physical and chemical performance test results of Example 1, Example 2, Example 3, Example 4 and Comparative Example 1 and Comparative Example 2 are shown in Table 1.

[0164] Table 1 Physical and chemical properties test results Note: The pore volume and average pore diameter are measured by a fully automatic specific surface area and pore size distribution analyzer. The values ​​of different particle sizes are obtained by sampling during the reaction process.

[0165] The electrical performance test results of Example 1, Example 2, Example 3, Example 4 and Comparative Example 1 and Comparative Example 2 are shown in Table 2.

[0166] Table 2 Electrical performance test results

[0167] It can be seen from Examples 1, 2, 3 and 4 that the Ni 0.33 Mn 0.33 Fe 0.34 (OH)2、Ni 0.28 Mn 0.36 Fe 0.36 (OH)2、Ni 0.32 Mn 0.32 Fe 0.32 Mg 0.04 (OH)2、Ni 0.32 Mn 0.33 Fe 0.33 Zn 0.02 NaNi synthesized from (OH)2 precursors 0.33 Mn 0.33 Fe 0.34 O2、NaNi 0.28 Mn 0.36 Fe 0.36 O2、NaNi 0.32 Mn 0.32 Fe 0.32 Mg 0.04 O2 and NaNi 0.32 Mn 0.33 Fe 0.33 Zn 0.02 The sodium-ion battery corresponding to the O2 positive electrode active material can simultaneously achieve good initial discharge specific capacity, initial coulombic efficiency, capacity retention rate, and rate performance. Comparative Example 1 does not have the special structure and morphology disclosed herein, and the consistency of the primary particle growth direction is not as good as that of Example 1. Although the initial coulombic efficiency is close to that of Example 1, the capacity retention rate, initial discharge specific capacity, and rate performance are significantly worse than those of Example 1. Comparative Example 2 has poor primary particle growth direction consistency. Although the initial discharge specific capacity is close to that of Example 1, the initial coulombic efficiency, capacity retention rate, and rate performance are not as good as those of Example 1.

[0168] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them. Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present disclosure.

[0169] Furthermore, those skilled in the art will appreciate that although some embodiments herein include certain features included in other embodiments but not other features, the combination of features from different embodiments is intended to be within the scope of this disclosure and to form different embodiments. For example, in the claims above, any of the claimed embodiments may be used in any combination. The information disclosed in this background section is intended solely to enhance understanding of the overall background of this disclosure and should not be construed as an admission or any form of implication that such information constitutes prior art already known to those skilled in the art. Industrial Applicability

[0170] In summary, the sodium ion battery positive electrode material precursor provided by the present disclosure includes a plurality of secondary particles, and the primary particles constituting the secondary particles grow by intercalation along the diameter direction of the secondary particles and have high consistency in the growth direction, which is beneficial to the transmission and deintercalation of sodium ions, thereby improving the rate performance of the sodium ion battery prepared by the corresponding positive electrode material.

Claims

1. A sodium ion battery cathode material precursor, wherein: The sodium ion battery positive electrode material precursor includes a plurality of secondary particles, and the growth direction consistency coefficient U of the primary particles constituting the secondary particles satisfies: U≥75%, U=(360-α) / 360*100%; Among them, α is the sum of the angles of all central angles that do not meet the specified conditions; the central angle is the central angle of the cross-section of the secondary particle with the center of the cross-section of the secondary particle as the vertex; the specified condition is: in the cross-section, in the outer layer of the fan-shaped area corresponding to the central angle, the primary particle grows by intercalation along the diameter direction of the cross-section.

2. The sodium ion battery cathode material precursor according to claim 1, wherein: One or more of the following conditions are met: A. The growth direction consistency coefficient U of the primary particles satisfies: U ≥ 85%; B. The primary particles are in the form of thin sheets, and the average thickness of the primary particles is 0.05-0.14 μm; C. The average pore size of the secondary particles is 13-15.5 nm, and the average pore volume is 0.042-0.065 cm 3 / g.

3. The sodium ion battery cathode material precursor according to claim 1, wherein: One or more of the following conditions are met: D. The particle size D50 of the precursor is 9.5-18 μm; E. The tap density TD of the precursor is not less than 1.8 g / cm 3 ; F. The specific surface area of ​​the precursor is 12-22m 2 / g; G. The particle size distribution Span of the precursor is 0.3-0.6; H. The half maximum width (FWHM) (100) of the precursor is 0.38-0.58°.

4. The sodium ion battery cathode material precursor according to any one of claims 1 to 3, wherein: The chemical formula of the sodium ion battery cathode material precursor is Ni x Mn y Fe 1-x-y-z Me z (OH)2, wherein 0.15≤x≤0.4, 0.2≤y≤0.5, 0≤z≤0.04; Me is selected from one or more of Zn, Ti, Mg, Al, Zr, and Ca.

5. A method for preparing a precursor of a positive electrode material for a sodium ion battery, wherein: include: Mixing materials including a complexing agent, a precipitant and water to obtain a base liquid; The target mixed metal salt solution, the precipitant and the complexing agent are added to the base solution in parallel, and under an inert gas atmosphere, the pH value of the reaction system, the reaction stirring rate and the flow rate of the target mixed metal salt solution are controlled to perform a coprecipitation reaction to obtain the sodium ion battery positive electrode material precursor; The mother liquor is continuously discharged during the coprecipitation reaction.

6. The method for preparing a precursor of a positive electrode material for a sodium ion battery according to claim 5, wherein: One or more of the following conditions are met: a. The pH value of the reaction system is 10-11; Preferably, the pH value of the reaction system is 10.4 to 11.0; b. During the coprecipitation reaction, the stirring rate is reduced by 10-100 r / min / time every 4-8 h until it is reduced to the minimum stirring rate; preferably, the minimum stirring rate setting principle is: when D50≤11 μm, the minimum stirring rate is 120 r / min; when 11 μm≤D50≤13 μm, the minimum stirring rate is 110 r / min; when 13 μm≤D50≤15 μm, the minimum stirring rate is 100 r / min; when 15 μm≤D50≤18 μm, the minimum stirring rate is 90 r / min; c. During the coprecipitation reaction, the flow rate of the target mixed metal salt solution is increased by 1.5-3 times of the previous flow rate every time the particle size D50 of the particles obtained by the reaction increases by 2-4 μm, until it increases to the maximum flow rate; the maximum flow rate is not higher than 8% / h of the volume of the reaction container; Preferably, the maximum flow rate is 6% / h to 8% / h of the volume of the reaction container; c '. The coprecipitation reaction temperature is 42 to 60 ° C; c". The complexing agent is ammonia water, and the ammonia concentration in the base liquid is 3.0-4.2 g / L.

7. The method for preparing a precursor of a positive electrode material for a sodium ion battery according to claim 5 or 6, wherein: One or more of the following conditions are met: d. The target mixed metal salt solution includes nickel salt, manganese salt, ferrous salt and Me salt; Me is selected from one or more of Zn, Ti, Mg, Al, Zr and Ca; e. After the coprecipitation reaction is completed, the method further comprises: solid-liquid separation to obtain a solid, followed by alkali washing, water washing, and drying to obtain the sodium ion battery positive electrode material precursor.

8. A sodium ion battery cathode material, wherein: The raw materials include the sodium ion battery positive electrode material precursor according to any one of claims 1 to 4.

9. A sodium ion battery, wherein: The raw materials include the sodium ion battery positive electrode material as claimed in claim 8.

10. An electrical device, wherein: Including the sodium ion battery as described in claim 9.

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