Sodium-poor phase primary battery positive electrode material and preparation method thereof

Abstract

The invention discloses a sodium-poor phase primary battery positive electrode material and a preparation method thereof, the battery positive electrode material is a material with a chemical general formula of NaxNiyCuzMnqO2, 0.05 < = x < = 0.2, 0 < = y < = 0.2, 0.1 < = z < = 0.3, 0.5 < = q < = 1.2-(x + y + z), and the sodium-poor phase positive electrode material with improved performance is prepared by a simple and feasible solid phase method.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery material preparation, in particular to a sodium-poor phase primary battery cathode material and a preparation method thereof. BACKGROUND

[0002] Primary batteries are mainly used in various intelligent meters, intelligent transportation, intelligent security and protection, medical devices and other fields, and have a wide range of market applications. At the same time, with the advent of the 5G era, the market demand for various intelligent meters, intelligent transportation and intelligent security has increased, indirectly driving the market demand for high-energy lithium primary batteries. The market development prospect of high-energy lithium primary batteries in China is optimistic. According to the data, the market size of the lithium primary battery industry in China in 2022 was about 6.26 billion yuan. The market size of primary batteries in 2023 reached 31.53 billion US dollars, with a compound annual growth rate of 4.3%. The market is mainly composed of lithium-manganese batteries, lithium-mercury batteries and lithium-fluorocarbon batteries. As people pay more and more attention to environmental protection and system safety and reliability in the 21st century, further in-depth research on battery systems with low price, high battery voltage, high energy density, wide operating temperature range, good high-rate discharge performance, long storage time, safety and environmental protection will become the focus of primary battery research.

[0003] The current sodium battery patent system is dominated by secondary batteries, and the related technology of sodium primary batteries has not yet been formed. In the future, technology research and development need to be promoted in combination with specific scene requirements (such as low power consumption and short cycle application). In the current public patent, there is no direct independent technical solution for sodium primary batteries. The existing technology improvement is still centered on secondary batteries. There is room for research and development in the direction of material selection (such as high-stability cathodes) and packaging technology (such as anti-leakage design) for sodium primary batteries. In view of the short cycle and low power consumption requirements (such as emergency equipment and micro sensors) of sodium primary batteries, lightweight packaging technology and high-stability sodium salt cathodes need to be developed. SUMMARY

[0004] The purpose of the present application is to provide a sodium-poor phase primary battery cathode material and a preparation method thereof. A simple and easy-to-implement solid-phase method is used to prepare a sodium-poor phase cathode material with improved performance, effectively solving the technical problems of voltage hysteresis, slow sodium diffusion kinetics and capacity far lower than the theoretical value in sodium batteries.

[0005] According to the sodium-poor phase primary battery cathode material provided by the present application, the battery cathode material is a material including a chemical formula Na x Ni y Cu z Mn q O2, wherein 0.05≤x≤0.2, 0≤y≤0.2, 0.1≤z≤0.3, and 0.5≤q≤1.2-(x+y+z).

[0006] The application further provides a preparation method of the sodium-poor phase primary battery positive electrode material. S1: mixing manganese dioxide, sodium carbonate and metal oxide and performing heating shearing dispersion to obtain mixed powder; S2: using a tablet press to press the mixed powder obtained in step S1 into small round tablets with a diameter of 0.5-5 cm and a thickness of 0.5-5 cm; S3: placing the small round tablets prepared in step S2 in a crucible and then performing calcination, and taking out after cooling to room temperature; S4: performing dry nano-grinder grinding treatment on the small round tablets to obtain the sodium-poor phase primary battery positive electrode material.

[0007] Further, the "heating shearing dispersion" in step S1 is performed at 120-200 DEG C in air, the shearing linear velocity is 10-40 m / s, and the time is 0.5-2 hours.

[0008] Further, the total tablet press pressure in step S2 is 2KN-20KN.

[0009] Further, the "calcination" in step S3 is performed in a muffle furnace / tube furnace.

[0010] Further, the grinding speed of the grinder in step S4 is 0.5-1.5 Kr / min, and the time is 0.5-2 hours.

[0011] The application has the following beneficial effects: 1. By controlling the sodium content at a low level (0.05≤x≤0.2), the sodium-poor phase positive electrode material is prepared, and compared with the traditional sodium ion battery positive electrode material with high sodium content (x≥0.5), the sodium-poor phase positive electrode material has higher energy density, and can significantly improve the overall performance of the battery.

[0012] 2. The process route of heating shearing dispersion, tablet pressing, calcination and dry grinding is adopted, and the sodium-poor phase positive electrode material with stable performance can be effectively prepared. Especially, the heating shearing dispersion process can uniformly mix the components, and improve the uniformity of the material; and the dry grinding process controls the particle size of the material in the range of 1-5 μm, which is beneficial to improve the electrochemical activity of the material and the discharge performance of the battery.

[0013] 3. The introduction of copper (0.1≤z≤0.3) and the control of the manganese content (0.5≤q≤1.2-(x+y+z)) improve the electrochemical performance of the material, especially improve the conductivity and structural stability of the material, thereby improving the electrochemical performance of the battery. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 The voltage-specific capacity curves of the embodiments 3, 4, 5 and 6 of the application are shown in the figure.

[0015] Figure 2 Voltage-capacity curve diagram of the sodium-deficient phase primary battery cathode material of the present application, Example 1 and 2.

[0016] Figure 3 Voltage-capacity curve diagram of the sodium-deficient phase primary battery cathode material of the present application, Example 1 and 7.

[0017] Figure 4 Voltage-capacity curve diagram of the sodium-deficient phase primary battery cathode material of the present application, Example 1, 2, 3, 5.

[0018] Figure 5 Impedance curve diagram of the sodium-deficient phase primary battery cathode material of the present application, Example 3 and 5, before and after discharging. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should fall within the scope of protection of the present application.

[0020] The present application provides a sodium-deficient phase primary battery cathode material, which is a material with a chemical general formula of NaxNiyCuzMnqO2, wherein 0.05≤x≤0.2, 0≤y≤0.2, 0.1≤z≤0.3, and 0.5≤q≤1.2-(x+y+z).

[0021] The present application also provides a preparation method of the sodium-deficient phase primary battery cathode material, comprising the following steps: S1: mixing manganese dioxide, sodium carbonate and metal oxides and performing heating shearing dispersion to obtain mixed powder; S2: using a tablet press to press the mixed powder obtained in step S1 into small round tablets with a diameter of 0.5-5 cm and a thickness of 0.5-5 cm; S3: placing the small round tablets prepared in step S2 in a crucible, and then performing calcination, and taking out after cooling to room temperature; S4: performing dry nano-grinding machine grinding treatment on the small round tablets to obtain the sodium-deficient phase primary battery cathode material.

[0022] In step S1, the "heating shearing dispersion" is performed at 120-200℃ in air, with a shearing linear velocity of 10-40 m / s and a time of 0.5-2 hours.

[0023] In step S2, the total pressure of the tablet press is 2KN-20KN.

[0024] The "calcination" in step S3 is calcination in a muffle tube furnace.

[0025] The grinding speed of the grinder in step S4 is 0.5-1.5 Kr / min, and the time is 0.5-2 hours.

[0026] The following multiple different embodiments are used for further illustration.

[0027] Example 1 S1: According to the molar ratio of Na 0.2 Ni 0.1 Cu 0.3 Mn 0.6 O2, 132g Na2CO3 (Shanghai Titan Science and Technology Co., Ltd. CAS No.: 497-19-8), 297g CuO (Shanghai Titan Science and Technology Co., Ltd. CAS No.: 1317-38-0), 93g NiO (Shanghai Aladdin Biochemical Technology Co., Ltd. CAS No.: 1313-99-1), and 648g MnO2 (Shanghai Maikelin Biotechnology Co., Ltd. CAS No.: 1313-13-9) are sequentially added in a heating and shearing device, the heating and shearing dispersion temperature is 120°C, the shearing linear speed is gradually increased to 20m / s, and the time is 0.5 hours. S2: The tablet press is used to press into small round tablets with a diameter of 2.5 centimeters and a thickness of 2 centimeters, and the pressure is 10KN. S3: The sample is placed in a crucible and calcined in a muffle tube furnace at 900°C for 12 hours, and then taken out after cooling to room temperature. S4: Dry nano-grinding machine grinding treatment is performed, the grinding speed is 1 Kr / min, and the time is 1 hour, to obtain a sodium primary battery sodium-poor phase positive electrode material Na 0.2 Ni 0.1 Cu 0.3 Mn 0.6 O2.

[0028] Example 2 S1: According to the molar ratio of Na 0.2 Ni 0.2 Cu 0.3 Mn 0.5 O2, 132g Na2CO3 (Shanghai Titan Science and Technology Co., Ltd. CAS No.: 497-19-8), 297g CuO (Shanghai Titan Science and Technology Co., Ltd. CAS No.: 1317-38-0), 93g NiO (Shanghai Aladdin Biochemical Technology Co., Ltd. CAS No.: 1313-99-1), and 648g MnO2 (Shanghai Maikelin Biotechnology Co., Ltd. CAS No.: 1313-13-9) are sequentially added in a heating and shearing device, the heating and shearing dispersion temperature is 120°C, the shearing linear speed is gradually increased to 30m / s, and the time is 0.5 hours. S2: The tablet press was pressed into a small disc with a diameter of 2.5 cm and a thickness of 2 cm, and the pressure was 5 KN; S3: Placed in a crucible, calcined at 900℃ for 12h in a muffle furnace under oxygen atmosphere, and taken out after cooling to room temperature; S4: Dry nano-grinding machine grinding treatment, grinding speed 1Kr / min, time 1 hour, to get sodium primary battery sodium-poor phase positive material Na 0.2 Ni 0.2 Cu 0.3 Mn 0.5 O2.

[0029] Example 3 S1: According to the molar ratio in Na 0.1 Cu 0.3 Mn 0.8 O2, 66g Na2CO3 (Shanghai Titan Technology Co., Ltd. CAS No.: 497-19-8), 297g CuO (Shanghai Titan Technology Co., Ltd. CAS No.: 1317-38-0), 720g MnO2 (Shanghai Macklin Biochemical Technology Co., Ltd. CAS No.: 1313-13-9) were added in sequence in a heating and shearing device, the heating and shearing dispersion temperature was 150℃, the shearing linear velocity was gradually increased to 30m / s, and the time was 0.5 hours; S2: The tablet press was pressed into a small disc with a diameter of 2.5 cm and a thickness of 2 cm, and the pressure was 10 KN; S3: Placed in a crucible, calcined at 700℃ for 12h in a tube furnace, and taken out after cooling to room temperature; S4: Dry nano-grinding machine grinding treatment, grinding speed 1Kr / min, time 1 hour, to get sodium primary battery sodium-poor phase positive material Na 0.1 Cu 0.3 Mn 0.8 O2.

[0030] Example 4 S1: According to the molar ratio in Na 0.1 Cu 0.2 Mn 0.8 O2, 66g Na2CO3 (Shanghai Titan Technology Co., Ltd. CAS No.: 497-19-8), 297g CuO (Shanghai Titan Technology Co., Ltd. CAS No.: 1317-38-0), 720g MnO2 (Shanghai Macklin Biochemical Technology Co., Ltd. CAS No.: 1313-13-9) were added in sequence in a heating and shearing device, the heating and shearing dispersion temperature was 150℃, the shearing linear velocity was gradually increased to 30m / s, and the time was 0.5 hours; S2: The tablet press was pressed into a small disc with a diameter of 2.5 cm and a thickness of 2 cm, and the pressure was 10 KN; S3: Place in a crucible, calcine in a tube furnace at 700°C for 12h, take out after cooling to room temperature; S4: Perform dry nano-grinder grinding treatment, grinding speed 1Kr / min, time 1 hour, to obtain sodium primary battery sodium-poor phase positive electrode material Na 0.1 Cu 0.2 Mn 0.8 O2.

[0031] Example 5 S1: According to the molar ratio in Na 0.2 Cu 0.3 Mn 0.7 O2, sequentially add 132g Na2CO3 (Shanghai Titan Technology Co., Ltd. CAS No.: 497-19-8), 297g CuO (Shanghai Titan Technology Co., Ltd. CAS No.: 1317-38-0), 756g MnO2 (Shanghai Macklin Biochemical Technology Co., Ltd. CAS No.: 1313-13-9) in a heating and shearing device, heating and shearing dispersion temperature 120°C, shearing linear velocity gradually increased to 30m / s, time 1 hour; S2: Press into small round pieces with a diameter of 2.5 centimeters and a thickness of 2 centimeters with a tablet press, pressure 10KN; S3: Place in a crucible, calcine in a tube furnace at 700°C for 15h, take out after cooling to room temperature; S4: Perform dry nano-grinder grinding treatment, grinding speed 1Kr / min, time 1 hour, to obtain sodium primary battery sodium-poor phase positive electrode material Na 0.2 Cu 0.3 Mn 0.7 O2.

[0032] Example 6 S1: According to the molar ratio in Na 0.2 Cu 0.4 Mn 0.6 O2, sequentially add 132g Na2CO3 (Shanghai Titan Technology Co., Ltd. CAS No.: 497-19-8), 396g CuO (Shanghai Titan Technology Co., Ltd. CAS No.: 1317-38-0), 648g MnO2 (Shanghai Macklin Biochemical Technology Co., Ltd. CAS No.: 1313-13-9) in a heating and shearing device, heating and shearing dispersion temperature 120°C, shearing linear velocity gradually increased to 30m / s, time 1 hour; S2: Press into small round pieces with a diameter of 2.5 centimeters and a thickness of 2 centimeters with a tablet press, pressure 10KN; S3: Place in a crucible, calcine in a tube furnace at 700°C for 15h, take out after cooling to room temperature; S4: dry method nanometer grinder grinding treatment, grinding speed 1 Kr / min, time for 1 hour, to get the sodium primary battery sodium-poor phase positive material Na 0.2 Cu 0.4 Mn 0.6 O2.

[0033] Example 7 S1: according to Na 0.05 Cu 0.3 Mn 0.8 O2, in the heating shear equipment, sequentially add 33g Na2CO3 (Shanghai Titan Technology Co., Ltd. CAS No: 497-19-8), 297g CuO (Shanghai Titan Technology Co., Ltd. CAS No: 1317-38-0), 864g MnO2 (Shanghai Maikelin Biotechnology Co., Ltd. CAS No: 1313-13-9), heating shear dispersion temperature 120℃, shear line speed gradually increased to 30m / s, time for 1 hour; S2: tablet press into a small round piece with a diameter of 2.5 centimeters and a thickness of 2 centimeters, pressure 10 KN; S3: placed in the crucible, calcined in the tube furnace at 700℃ for 15h, cooled to room temperature and taken out; S4: dry method nanometer grinder grinding treatment, grinding speed 1 Kr / min, time for 1 hour, to get the sodium primary battery sodium-poor phase positive material Na 0.05 Cu 0.3 Mn 0.8 O2.

[0034] It is worth noting that the Shanghai Titan Technology Co., Ltd. CAS No: **** mentioned in each of the above embodiments is the specific manufacturer name and reagent code of the production reagent, and has no other special meaning.

[0035] It needs to be explained that in the drawings Figures 1 to 4 The voltage-specific capacity test data graphs of Examples 1-6 under different conditions are compared in detail.

[0036] Comparing Example 1 and Example 2 (hereinafter referred to as Example 1 and Example 2), the main difference between the two is 1, composition: Example 1 (y=0.1) vs Example 2 (y=0.2), Na (x=0.2) and Cu (z=0.3) are unchanged, but Mn is different, Example 1 (q=0.6) vs Example 2 (q=0.5); 2, preparation: Example 2 uses oxygen calcination atmosphere (Example 1 is air) and lower tabletting pressure 5 KN (Example 1 is 10 KN); Therefore, Ni doping can stabilize the manganese dioxide lattice, reduce the volume expansion of sodium ion intercalation, and improve the structural stability. Ni enhances the doping effect, but too much Ni may block the sodium vacancies and affect ion diffusion.

[0037] The oxygen atmosphere of Example 2 promotes metal oxide intercalation and improves material purity and electrical conductivity.

[0038] The lower pressure of Example 2 reduces the tightness of particle contact, but has little effect after calcination.

[0039] Figure 2 (Na 0.2 Ni y Cu 0.3 Mn q The discharge capacity of the O2 series shows that Example 2, Proportion 1, has slightly higher discharge capacity, but the difference is not large, but too much Ni may lead to a decrease in Mn activity.

[0040] Comparative Example 3, Example 5, and Example 7 (hereinafter referred to as Example 3, Example 5, and Example 7) mainly differ in: 1. Composition: Example 3 (x = 0.1), Example 5 (x = 0.2), Example 7 (x = 0.05), Cu (z = 0.3) remains unchanged, but Mn is different, Example 3 (q = 0.8), Example 5 (q = 0.7), and Example 7 (q = 0.8); 2. Preparation: Example 5 and 7 have a longer calcination time of 15 h; The effect of Na content (x): Introducing sodium vacancies in the Na layer can accelerate the diffusion of sodium ions and solve the problem of "voltage hysteresis and slow sodium diffusion kinetics". Reducing x (Example 7, x = 0.05) increases the number of vacancies, but too low x (such as x = 0.05) may reduce the number of de-intercalated sodium ions and reduce the theoretical capacity. Higher x (Example 5, x = 0.2) has great capacity potential, but has fewer vacancies and slower diffusion.

[0041] Calcination time: The 15 h calcination of Example 5 and Example 7 (12 h for Comparative Example 3) may enhance the crystallinity, but the energy consumption increases.

[0042] Figure 1 (Na x Cu z Mn q The discharge capacity of the O2 series shows that x = 0.1 (Example 3) and x = 0.05 (Example 7) have higher discharge capacity and better rate performance than x = 0.2 (Example 5), confirming the advantage of sodium deficiency, but the capacity of x = 0.05 (Example 7) may be slightly lower than x = 0.1 (Example 3) due to insufficient sodium ions.

[0043] Figure 5 (Na x Cu z Mn qThe lower x (Example 7), the smaller impedance (faster sodium diffusion) can be shown, but the capacity-impedance needs to be balanced when x = 0.05.

[0044] From the above, it can be seen that the sodium-poor design (x = 0.05-0.1) significantly improves the sodium ion kinetics, x = 0.1 is a better value (balance capacity and diffusion), and x = 0.2 (Example 5) has higher capacity but poorer performance.

[0045] Comparative Example 3, Example 4 and Example 6 (hereinafter referred to as Example 3, Example 4 and Example 6) mainly differ in: 1. Composition: Example 3 (x = 0.1, z = 0.3, q = 0.8), Example 4 (x = 0.1, z = 0.2, q = 0.8), Example 6 (x = 0.2, z = 0.4, q = 0.6); 2. Preparation: Example 4 and Example 6 have longer heating and shearing time (1 h), and Example 3 is 0.5 h; Cu doping at sodium sites can stabilize the lattice structure, reduce the volume expansion during sodium ion intercalation, and inhibit Jahn-Teller distortion; z = 0.3 (Example 3): at low sodium (x = 0.1), Cu provides structural stability, while the Mn active site is sufficient (q = 0.8), z = 0.2 (Example 4): insufficient Cu doping leads to a decrease in structural stability, and the capacity may be lower than Example 3, z = 0.4 (Example 6): high Cu blocks sodium vacancies or dilutes Mn active sites (q = 0.6); Figure 1 (Na x Cu z Mn q O2 series discharge capacity) shows that Cu doping improves the specific capacity, and too high Cu is not conducive.

[0046] The heating and shearing parameters of Comparative Example 3 and Example 4 differ in that: the heating and shearing dispersion temperature / shearing speed / time of Example 3 is 150°C / 30 m / s / 0.5 h, and that of Example 4 is 120°C / 30 m / s / 1 h; the higher temperature (150°C) of Example 3 can promote the pre-reaction of raw materials and improve uniformity, and the longer shearing time (1 h) of Example 4 can compensate for the defects at low temperature, but the efficiency is lower.

[0047] The calcination parameters of Comparative Example 1, Example 3 and Example 5 differ in that: the temperature of Example 1 (900°C), and that of Example 3 and Example 5 (700°C), the calcination time of Example 5 (15 h), and that of Example 1 and Example 3 (12 h); The calcination atmosphere of Example 2 (oxygen), and others (air) The 900°C calcination of Example 1 and Example 2 promotes lattice reorganization and doping, but the energy consumption is high.

[0048] The 700°C in Examples 3 and 5 may be sufficient to complete the reaction (especially for Ni-free systems).

[0049] Oxygen atmosphere (Example 2) increases the oxidation state of the material and enhances its conductivity.

[0050] Calcination for 15 h may slightly improve crystallinity, but the returns are diminishing.

[0051] Therefore, for the Ni-free system (such as Example 3), 700°C / 12 h is sufficient; for the Ni-containing system (Examples 1 / 2), 900°C is required to activate the doping, and a press pressure of 10 kN (Example 1) is better than 5 kN (Example 2).

[0052] From the above summary, it can be seen that the sodium-poor component design introduces sodium vacancies in the Na layer to achieve dual sodium site doping of Cu and Ni in the manganese dioxide lattice. In the entire preparation method, the raw materials are pre-heated, sheared and baked to make the raw materials more evenly mixed to obtain a modified manganese oxide precursor. The precursor is then pressed into a disc to make the contact between the particles closer and the area available for reaction larger. Then, by calcining in an air atmosphere, the metal oxides and metal salts in the precursor are embedded in the manganese dioxide lattice at high temperature, stabilizing the crystal structure and reducing the volume expansion during the sodium ion embedding process. The dry nano-grinder is then used for grinding to control the particle size to 1-5μm. The smaller the particle size, the more conducive it is to the embedding and deintercalation of sodium ions, which is beneficial to improving the rate performance of sodium batteries. At the same time, the smaller the particle size, the higher the material capacity. Through the above method, a sodium-poor phase positive electrode material with improved performance can be prepared, which effectively solves some key technical problems existing in sodium batteries, such as voltage hysteresis, slow sodium diffusion kinetics and capacity far below the theoretical value.

[0053] In general, the beneficial effects of this application are: 1. By controlling the sodium content at a lower level (0.05≤x≤0.2), a sodium-poor phase positive electrode material is prepared. Compared with the traditional sodium-ion battery positive electrode material with a high sodium content (x≥0.5), the sodium-poor phase positive electrode material of the present invention has a higher energy density and can significantly improve the overall performance of the battery.

[0054] 2. The present invention utilizes a process involving heat-shear dispersion, tableting, calcination, and dry grinding to effectively produce a sodium-poor cathode material with stable performance. In particular, the heat-shear dispersion process enables uniform mixing of the components, improving material uniformity; while the dry grinding process controls the particle size within the 1-5 μm range, which helps improve the electrochemical activity of the material and the battery's discharge performance.

[0055] 3. Introducing copper (0.1≤z≤0.3) and controlling the content of manganese (0.5≤q≤1.2-(x+y+z)), which improves the electrochemical performance of the material, especially improves the conductivity and structural stability of the material, thereby improving the electrochemical performance of the battery.

[0056] The above merely describes the preferred embodiments of the present application. It should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A sodium-poor phase primary battery positive electrode material, characterized in that: The battery positive electrode material includes a chemical formula of Na x Ni y Cu z Mn q O2 material, wherein 0.05≤x≤0.2, 0≤y≤0.2, 0.1≤z≤0.3, 0.5≤q≤1.2-(x+y+z).

2. A method for preparing a sodium-poor phase primary battery positive electrode material according to claim 1, characterized in that: Including steps: S1: mixing manganese dioxide, sodium carbonate and metal oxide and performing heating and shearing dispersion to obtain a mixed powder; S2: The mixed powder obtained in step S1 is pressed into small round tablets with a diameter of 0.5-5 cm and a thickness of 0.5-5 cm using a tablet press; S3: placing the small disc obtained in step S2 in a crucible, calcining it, and taking it out after cooling to room temperature; S4: Grind the small discs with a dry nano-grinder to obtain a sodium-poor phase primary battery positive electrode material.

3. The method for preparing a sodium-poor phase primary battery positive electrode material according to claim 2, characterized in that: The metal oxides are copper oxide and / or nickel oxide.

4. The method for preparing a sodium-poor phase primary battery positive electrode material according to claim 2, characterized in that: The "heating shearing dispersion" in step S1 is performed in air at 120-200°C, with a shearing linear speed of 10-40 m / s and a time of 0.5-2 hours.

5. The method for preparing a sodium-poor phase primary battery positive electrode material according to claim 2, characterized in that: The total tablet press pressure in step S2 is 2KN to 20KN.

6. The method for preparing a sodium-poor phase primary battery positive electrode material according to claim 2, characterized in that: In step S3, the calcination is carried out in a muffle furnace / tube furnace.

7. The method for preparing a sodium-poor phase primary battery positive electrode material according to claim 2, characterized in that: In step S4, the grinding speed of the grinding machine is 0.5-1.5Kr / min, and the grinding time is 0.5-2 hours.

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