CN116375107A

CN116375107A - Manufacturing method and manufacturing system of sodium ion battery anode material

Info

Publication number: CN116375107A
Application number: CN202310347001.2A
Authority: CN
Inventors: 王鸣玉; 杨力博; 任国锋
Original assignee: Sany Technology Equipment Co Ltd
Current assignee: Sany Technology Equipment Co Ltd
Priority date: 2023-03-31
Filing date: 2023-03-31
Publication date: 2023-07-04

Abstract

The application relates to the technical field of sodium ion batteries, and particularly provides a manufacturing method and a manufacturing system of a sodium ion battery anode material. The preparation method comprises weighing raw materials according to preset molar ratio, wherein each raw material comprises sodium source and one or more compound raw materials containing transition metal element; crushing the raw materials to a preset size by using a first crushing system; dry material mixing is carried out on all the crushed raw materials; sintering the mixed raw materials to obtain sodium-containing oxide; and crushing and screening the sodium-containing oxide by using a dry material crushing and screening system to obtain the layered oxide type sodium-electricity anode material. The whole process is a dry process, does not need to add a solvent, does not need to remove the solvent and dry before firing, remarkably simplifies the manufacturing process, does not need to mix grinding impurities, improves the purity of raw materials and the purity of products, can improve the mixing effect, improves the reaction sufficiency of each raw material during sintering, and improves the quality and electrochemical performance of finished products of sintered products.

Description

Manufacturing method and manufacturing system of sodium ion battery anode material

Technical Field

The application relates to the technical field of sodium ion batteries, in particular to a manufacturing method and a manufacturing system of a positive electrode material of a sodium ion battery.

Background

A sodium ion battery is a secondary battery (rechargeable battery) that mainly operates by means of sodium ions moving between a positive electrode and a negative electrode. During charge and discharge, na ions are inserted and extracted back and forth between the two electrodes. The sodium ion battery is mainly characterized in that sodium ions are utilized to replace lithium ions with high price, so that the anode material, the cathode material, electrolyte and the like of the battery are correspondingly changed to adapt to the movement characteristics of the sodium ions. The preparation process of the battery anode material has unique requirements and cannot be simply prepared by a lithium ion preparation process due to the change of the battery anode material.

At present, when sodium raw materials, transition metal and other raw materials are crushed and mixed, the raw materials are mainly mixed by a wet method, namely, firstly, solid raw materials are mixed with a solvent with a lubricating effect, then, grinding is carried out by a mixer such as a sand mill, a ball mill and the like, the raw materials are crushed and mixed in the solvent to form slurry, then, drying is carried out to remove the solvent in the slurry and dry the mixture to reach a sintering premise, and then, the mixture can be sintered at a high temperature to obtain a required material prototype. The wet mixing process is not only tedious, but also is easy to mix with grinding media in the grinding crushing process, and the grinding cavity is also easy to be worn by abrasion, so that worn substances are doped into the slurry to become impurities, which can affect the purity of the slurry and the electrochemical performance of the finally obtained material.

Disclosure of Invention

In view of this, the embodiments of the present application are directed to providing a method for manufacturing a sodium battery material, so as to solve the problems that the process of wet mixing is complicated and impurities are easily mixed in the material to affect the performance in the prior art.

In one aspect, the present application provides a method for manufacturing a positive electrode material of a sodium ion battery, including the following steps:

weighing raw materials according to a preset molar ratio, wherein the raw materials comprise a sodium source and one or more compound raw materials containing transition metal elements;

crushing the raw materials to a preset particle size by using a first crushing system;

mixing the crushed raw materials by using dry material mixing equipment to obtain a mixed raw material;

sintering the mixed raw materials in a gas environment by using a sintering system to obtain sodium-containing oxide;

and crushing and screening the sodium-containing oxide by using a dry material crushing and screening system to obtain the required layered oxide type sodium-electricity positive electrode material.

In one possible embodiment, the crushing of the raw materials to a predetermined particle size using the first crushing system includes the following:

grouping the raw materials according to hardness grades, and dividing the raw materials into components with different hardness grades;

The raw materials of all the components are added into the same crushing system through different crushing paths to realize crushing and mixing, wherein the different crushing paths have different crushing forces, and the raw materials of all the components are added into the crushing paths with the crushing force level and the matching crushing path according to the hardness level.

In one possible embodiment, the dry mix device comprises a gas flow mixer; and/or the dry material crushing and screening system is a second air crushing system.

In one possible embodiment, the method further comprises: introducing all the crushed raw materials of the first crushing system into the airflow mixer by using the same induced air pipeline, so that all the crushed raw materials are subjected to primary mixing in the induced air pipeline, and secondary mixing in the airflow mixer.

In one possible embodiment, the method further comprises: and (3) carrying out dust removal treatment on the air flow discharged in each step, and taking the purified air flow after the dust removal treatment as a circulating air source for recycling.

In one possible embodiment, the method further comprises the step of recovering heat from the tail gas discharged from the sintering system by using a heat exchange system and heating a circulating air source for crushing the materials by using the recovered heat.

In one possible embodiment, the compound raw materials include an iron source, a manganese source, a nickel source and a doping element, and the molar ratio of the elements of the sodium source, the iron source, the manganese source, the nickel source and the doping element is 1-1.1:0.2-0.9:0.05-0.9:0.1-0.9: 0-0.1; wherein the molar ratio of the sodium source to the elements of the compound raw material is 1-1.1:1.

In one possible embodiment, the sodium source is one or more of sodium carbonate, sodium dihydrogen phosphate, sodium sulfate, sodium nitrate, sodium hydroxide, sodium acetate and sodium oxalate, and the manganese source is one or more of manganese dioxide, manganous oxide, manganous oxalate, manganese sulfate, manganese carbonate and manganese nitrate; the doping element is one or more of copper, titanium, magnesium, vanadium, niobium, lithium, aluminum, tungsten, molybdenum, chromium, silicon, strontium, zirconium, boron, zinc and calcium.

In one possible embodiment, when the mixed raw materials are sintered in a gas environment by using a sintering system, the sintering temperature is 500-1200 ℃ and the sintering time is 8-24 hours;

or when the mixed raw materials are sintered in a gas environment by using a sintering system, the mixed raw materials are sintered for the first time at 600-1100 ℃ for 2-12 hours; and then sintering for the second time, wherein the temperature of the second sintering is 500-900 ℃ and the sintering time is 2-12h.

In one possible embodiment, the first crushing system comprises at least one multi-material crusher or a plurality of single-material crushers, and at least two layers of crushing paths arranged along the height direction of the crushing cavity are arranged on the multi-material crusher.

The application also provides a positive electrode material manufacturing system of the sodium ion battery, which comprises the following components: a first crushing system having a crushing chamber and a crushing path for feeding material and air flow into the crushing chamber for crushing the raw material; the air flow mixer is connected with a material outlet of the first crushing system through an induced air pipeline so as to mix crushed raw materials; the sintering system comprises primary sintering equipment and secondary sintering equipment, and is used for receiving the mixed raw materials discharged by the airflow mixer and sintering the mixed raw materials; and the dry material crushing and screening system is used for crushing and screening the products of the sintering system.

In one possible embodiment, the dry material crushing and screening system includes a second air crushing system for crushing the sodium-containing oxide, the making system further comprising: the first dust removal system is characterized in that an exhaust gas inlet is respectively connected with the first air crushing system and an exhaust port of the air flow mixer, and a clean gas outlet is connected with an air inlet of the first air crushing system; the waste gas inlet of the second dust removing system is connected with the exhaust port of the second air crushing system, and the clean gas outlet of the second dust removing system is connected with the air inlet of the second air crushing system; the heat exchange system is provided with a heat return pipeline for absorbing the heat of the exhaust gas of the sintering system, a first heat supply pipeline for supplying the heat to the first crushing system and a second heat supply pipeline for supplying the heat to the second crushing system.

In one possible embodiment, the first crushing system comprises a multi-material crusher, wherein a material outlet, a classification wheel and a first crushing path and/or a second crushing path are/is arranged on a crushing cavity of the multi-material crusher; the first crushing path comprises a feeding layer and an air inlet layer, the feeding layer comprises at least one first material nozzle, and the air inlet layer comprises at least two first air flow nozzles which are circumferentially arranged along the crushing cavity; the second crushing path is a mixed material layer, at least one layer is arranged in the height direction and comprises at least two combined nozzles which are circumferentially arranged along the crushing cavity, a second airflow nozzle and a second material nozzle are formed on a nozzle main body of the combined nozzle, wherein the second material nozzle and the second airflow nozzle are sleeved, or the second airflow nozzle and the second material nozzle are close to each other along the direction close to the nozzle; the classifying wheel is positioned in the crushing cavity and arranged at the material outlet so that the material particles reach the preset size and are sprayed out through the material outlet.

In one possible embodiment, at least two second air flow nozzles are arranged on the same combined nozzle, at least two second air flow nozzles are arranged around the second material nozzle along the circumferential direction of the second material nozzle, and the extension lines of the axes of the second air flow nozzles converge to the same point.

In one possible implementation manner, in the height direction of the crushing cavity, the material outlet is formed at the top, at least two layers of the first crushing paths and/or the second crushing paths are arranged, and each second crushing path is located below all the first crushing paths.

According to the manufacturing method of the sodium electric material, the raw materials are crushed in a pneumatic crushing mode, the raw materials are crushed to the required granularity, so that the raw materials can be uniformly and thoroughly mixed, the raw materials are mixed by adopting a dry mixing method, and then the crushed raw materials are mixed by dry material mixing equipment such as an airflow mixer or a coulter mixer, so that the mixing degree and the mixing effect of the raw materials can be improved, a solvent is not required to be added in the whole crushing and mixing process, no grinding medium is required to be involved, no impurity is doped in the raw materials, and the purity of the raw materials and the purity of a final product can be improved; and after the raw materials are uniformly mixed, sintering, and further crushing dry materials, such as air crushing and screening, after sintering, the required anode material can be obtained. The whole raw material treatment process is a dry process, and solvents are not required to be added during crushing and mixing, grinding is not required, solvent removal and drying before sintering are not required, so that the manufacturing process of the positive electrode material of the sodium ion battery is remarkably simplified, and the complexity is reduced; simultaneously, all materials with different hardness are crushed to the required fine granularity by a crushing mode, and dry mixing is carried out, so that on one hand, no impurities are doped into the raw materials, the purity of the raw materials and the purity of a final product can be improved, and the electrochemical performance of the obtained anode material is improved; on the other hand, the method is not influenced by the adverse effect of solvent adding and removing operation on the mixing effect, the raw materials can be uniformly and thoroughly mixed, the raw materials with different hardness are uniformly mixed in fine particles and then sintered, the reaction sufficiency of the raw materials can be improved, the quality of a finished product of a sintered product is improved, and the electrochemical performance of the obtained anode material is improved.

Drawings

FIG. 1 is a flow chart illustrating the fabrication of a positive electrode material for a sodium ion battery in an embodiment of the present application;

FIG. 2 is a schematic diagram of a system for manufacturing a positive electrode material of a sodium ion battery according to an embodiment of the present application;

FIG. 3 is a schematic view of a multiple material pulverizer in an embodiment of the present application;

FIG. 4 is a schematic view of a first direction of a composite nozzle according to an embodiment of the present application;

FIG. 5 is a schematic diagram of a half-section of a composite nozzle in an embodiment of the present application;

FIG. 6 is a schematic view of a second direction of a composite nozzle according to an embodiment of the present application;

FIG. 7 is a graph showing XRD patterns of test example 1 and comparative example 1 in the examples of the present application;

FIG. 8 is a graph showing the charge-discharge cycle curves of test example 1, comparative example 1, and comparative example 2 in the examples of the present application;

FIG. 9 is a SEM image of the product of test example 1 in the examples of the present application.

In fig. 1-9:

10. a first shredding system; 20. an air flow mixer; 30. a sintering system; 40. a first dust removal system; 50. a second dust removal system; 60. a second air-crushing system; 70. a heat exchange system; 80. a first gas source processing system; 90. a second gas source processing system; 100. a tail gas treatment system;

11. A multi-material pulverizer; 1. a crushing cavity; 101. a material outlet; 2. a first material nozzle; 3. a first air flow nozzle; 4. a combination nozzle; 41. a nozzle body; 42. a second material nozzle; 43. a second air flow nozzle; 431. a wide diameter section; 432. a narrow diameter section; 433. a spout; 44. a mounting plate; 5. and (5) a grading wheel.

Detailed Description

The following description of the technical solutions in the embodiments of the present application will be made clearly and completely with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

Referring to fig. 1-9, an embodiment of the present application provides a method for manufacturing a positive electrode material of a sodium ion battery, which includes the following steps:

s01, weighing raw materials according to a preset molar ratio, wherein the raw materials comprise a sodium source and one or more metal element raw materials in transition metals (the transition metals refer to transition metals in the periodic table of elements, such as chromium, manganese, iron, cobalt, nickel, copper, zinc, palladium, silver, platinum, gold, mercury and the like);

S02, using a first crushing system to crush all the raw materials which are weighed and assembled according to the mole ratio into preset particle sizes, for example, all the raw materials with different hardness are crushed into fine particles;

s03, mixing all the crushed raw materials by using dry material mixing equipment, so that all the raw materials which are crushed into particles or powder are uniformly mixed together to obtain mixed raw materials;

s04, sintering the mixed raw materials in a gas environment by using a sintering system, wherein the gas environment is an oxygen environment or an inert gas environment according to requirements, or can be directly an air environment, and the sintering can be performed at a sintering temperature of 500-1200 ℃ for 8-24 hours or performed for multiple times, for example, the first sintering is performed at 600-1100 ℃ for 2-12 hours; then carrying out secondary sintering, wherein the temperature of the secondary sintering is 500-900 ℃ and the sintering time is 2-12 hours, so that all raw materials are subjected to chemical reaction at high temperature to form a sinter containing sodium and transition metal, namely sodium-containing oxide;

s05, crushing and classifying the sodium-containing oxide obtained after sintering by using a dry material crushing and classifying system to obtain a layered oxide type sodium-electricity positive electrode material (sodium-ion battery positive electrode material, simply called sodium-electricity positive electrode material) containing sodium and transition metal, wherein the layered oxide type sodium-electricity positive electrode material is of a required size. Layered oxide type refers to a material in which the transition metal arrangement state is layer by layer in the lattice state of the material. But macroscopically layered oxide type sodium-electricity positive electrode material is granular powder.

The method comprises the steps of crushing raw materials in an air crushing mode, wherein the raw materials can be crushed separately or jointly, for example, crushing the raw materials in the same or a connected crushing cavity through crushing paths with different crushing forces (or called cavity inlet paths, namely paths entering the crushing cavity), so that the raw materials with different hardness are crushed to the required granularity, such as the granularity level required by sintering, the crushing effect is good, the particle size is controllable, and the raw materials can be crushed uniformly and mixed uniformly. No solvent is added as a lubricating medium and no grinding is performed using a grinding medium such as a grinding rod. And the dry mixing is adopted for mixing the raw materials, such as the thorough crushing of the raw materials by dry material mixing equipment such as an airflow mixer or a coulter mixer, so that the fine granular raw materials are comprehensively and thoroughly mixed, the mixing degree and the mixing effect of the raw materials can be improved, and the uniformity of the raw materials is ensured. And there is no need to mix in a solvent, so there is no need to dry after mixing to remove the solvent and to achieve the drying conditions required for sintering. And sodium-containing oxide generated after sintering the mixed raw materials is crushed and sieved by a dry crushing and sieving system, so that the required anode material can be obtained. The whole process is a dry process.

On one hand, compared with the wet mixing in the prior art, the whole manufacturing process is a dry process, solvent is not required to be added during crushing and mixing, solvent removal and drying before sintering are not required, the dry mixed raw materials obtained through the first crushing system and the dry mixing equipment can meet the requirements of granularity, dryness and the like required by sintering, sintering can be directly carried out, and the required anode material can be obtained through crushing and screening of the dry materials after sintering, so that the manufacturing process of the anode material of the sodium ion battery is remarkably simplified, the complexity is reduced, the solvent is not required to be used in the whole process, the waste water emission is remarkably reduced, and a complex waste water purification system is not required to be matched; in the second aspect, the raw materials are crushed in a gas crushing mode, a solvent is not required to be added, grinding media are not required to be used for grinding, impurities formed by incomplete removal of abradant and solvent are prevented from being mixed into the raw materials, the purity of the raw materials is improved, the reaction sufficiency of each raw material during sintering can be promoted, the purity of the finally obtained positive electrode material can be improved, and the performance of the obtained positive electrode material is improved; in the third aspect, materials with different hardness are crushed to the required fine granularity in a pneumatic crushing mode and are well mixed, the particle size is controllable and adjustable, the materials can be crushed to the required granularity, the materials are uniformly and thoroughly mixed, the mixing degree and the mixing effect of the materials can be improved, the wet mixing effect in the prior art is controlled by sanding time, the phenomenon that the particle size is different possibly exists, a solvent quick drying system is required to be equipped when the mixed slurry is dried before solvent removal and sintering, otherwise, the raw materials with different molar ratios are easy to laminate, the final mixing effect is poor, the raw materials with different hardness are well mixed by the pneumatic crushing and the dry mixing operation in the application, the adverse influence of the solvent adding and removing operation on the mixing effect is avoided, the raw materials can be uniformly and thoroughly mixed, the mixing degree influences the subsequent sintering effect, the thorough and uniform good mixing effect of the raw materials realized in the application can be avoided, the problems of incomplete crushing of the raw materials with higher partial hardness or the incomplete mixing of the raw materials, the raw materials can be caused to react in the high-temperature sintering process, the problem of insufficient reaction in the high-temperature sintering process is solved, the uniform mixing effect of the raw materials with different hardness is improved, the obtained raw materials can be fully sintered, the quality of the obtained raw materials can be fully sintered, and the obtained raw materials are well mixed, and the quality of the obtained raw materials can be fully sintered, and the quality is improved, and the quality of the obtained raw materials can be well sintered, and the quality is fully sintered.

Therefore, the manufacturing method of the sodium ion battery positive electrode material provided by the application not only remarkably simplifies the manufacturing process and reduces the complexity, but also can improve the purity and quality of the final obtained positive electrode material and the chemical property of the obtained positive electrode material.

When each raw material is crushed by the first crushing system, the raw material can be crushed once or crushed multiple times (multiple times refer to two or more times), for example, the crushed raw material is firstly crushed in a first-stage crusher, then enters a second-stage crusher to be crushed, and finally is introduced into a dry material mixing device for mixing after the multi-stage crushing is finished.

The sodium source in the raw material is a sodium-containing compound, and can be one compound or a plurality of compounds, such as one or more of sodium carbonate, sodium dihydrogen phosphate, sodium sulfate, sodium nitrate, sodium hydroxide, sodium acetate and sodium oxalate.

The transition metal may include iron, manganese, nickel, and may further include a doping element, and the doping element may include one or more of copper Cu, titanium Ti, magnesium Mg, vanadium V, niobium Nb, lithium Li, aluminum Al, tungsten W, molybdenum Mo, chromium Cr, silicon Si, strontium Sr, zirconium Zr, boron B, zinc Zn, calcium Ca. The transition metal may be obtained from a compound such as an oxide or a salt containing the desired metal. For example, the feedstock includes one or more compounds of an iron source, a manganese source, a nickel source, and may also include one or more compounds containing doping elements. For example, the manganese source may be one or more of manganese dioxide, manganomanganic oxide, manganese oxalate, manganese sulfate, manganese carbonate, manganese nitrate. The nickel source may be one or more of nickel sulfate, nickel nitrate, nickel monoxide, nickel hydroxide, and the iron source may be one or more of ferric oxide, ferric sulfate, ferric hydroxide, and the like.

The different application scenes of the sodium ion battery can lead to the deviation of the performance requirements of the sodium ion battery, such as the first coulombic efficiency, the first discharge capacity, the discharge multiplying power, the charge-discharge cycle performance and the like, and the composition elements and the proportion of the composition elements of the positive electrode material can be different. During preparation, different raw material compositions and proportions are selected according to the performance requirements of the required anode material.

In some embodiments, the sodium source, the iron source, the manganese source, the nickel source and the doping element R are mixed according to the element molar ratio m (Na: fe: mn: ni: R) =1-1.1:0.2-0.9:0.05-0.9:0.5-0.9: 0-0.1 (wherein 0 refers to no doping element), wherein the sum of the element mole ratios of Fe, mn and Ni is 1, the element mole ratio of the sodium source and other compound raw materials is 1-1.1:1, and the raw materials are respectively weighed.

For example, sodium carbonate, ferric oxide, nickel oxide and manganese oxide are mixed according to a mole ratio of 1.1: weighing 0.15:0.8:0.05, crushing and mixing according to the method, sintering at 700 ℃ for 20 hours, crushing and screening the obtained sodium-containing oxide to obtain the layered oxide sodium-electricity positive electrode material with the granularity of 1-5 mu m, wherein the particles of the obtained layered oxide sodium-electricity positive electrode material are uniform and the particle size is uniform as shown in an electron microscope photograph in figure 9. The intercalation quantity of metal elements in the obtained layered oxide sodium-electricity positive electrode material for embedding the metal elements into the crystal lattice is large and uniform, and the material has large charge-discharge capacity and good cyclic charge-discharge performance.

In order to improve the crushing degree and the mixing degree of each raw material, when the raw materials are selected, the raw materials with the granularity within a certain range, for example, the granularity is 30 mu m-3mm, and the raw materials are crushed in a gas crushing mode, and the optimal feeding granularity of a gas crusher can be not higher than 3mm.

When the first air pulverizing system is used to pulverize various materials to desired particle size, the materials with different hardness may be pulverized separately (for example, each material is pulverized by a single air pulverizer), and then mixed, or the materials with different hardness may be pulverized in the same batch (for example, the materials are pulverized and mixed in the same batch by a multi-material pulverizer with multiple pulverizing paths).

For example, the proportioned raw materials are grouped according to hardness grades, and are divided into components with different hardness grades; and then adding the raw materials of all the components into the same crushing system (like a crushing cavity) through different crushing paths to realize crushing and mixing, wherein the different crushing paths have different crushing forces, so that the materials can generate different impact forces to generate different crushing effects, and the crushing forces are in a direct proportion relation with the impact forces and the crushing effects. The raw materials of each component are added into a crushing path which is arranged according to the crushing strength according to the hardness level, so that the crushing strength level is matched with the hardness level.

Namely, the raw materials are classified and grouped according to the hardness range, one or more raw materials with similar hardness are a group, then the group of raw materials with higher hardness are added into a crushing path with larger crushing strength, and the raw materials with smaller hardness are added into the crushing path with smaller crushing strength. The crushing paths are arranged in a level mode according to the strength, the raw materials are arranged in a level mode according to the hardness, the raw materials are matched according to the level, the hardest raw materials are added into the crushing system through the path with the largest crushing strength, the hardest raw materials are added into the crushing system through the path with the smallest crushing strength, and the raw materials with the smallest hardness are added into the crushing system through the path with the smallest crushing strength. The pulverizing paths are communicated with the same pulverizing chamber, so that the pulverizing paths may be referred to as inlet paths. The material can take place the first collision and smash under the impact of this crushing route jet after getting into crushing chamber, and the dynamics of first collision is bigger (the dynamics of striking is relevant with factors such as material speed, air current speed), and crushing effect is better, and the dynamics of smashing of this route is bigger.

From this, through adding the multiple raw materials branching diameter that hardness is different, the route that crushing dynamics is big is matchd to the raw materials that hardness is big, and the raw materials of each different hardness can smash in same crushing intracavity, through the assurance of different crushing dynamics, not only can ensure that each raw materials is all smashed to required particle size, ensures crushing effect, and can just mix at crushing process. The material discharged from the first pulverizing device is the mixed raw material which is primarily mixed, and the material is mixed again by the dry material mixing device, so that the overall mixing time is prolonged, and the mixing effect is improved.

The dry material mixing equipment can be an airflow mixer, a coulter mixer and other equipment. In some embodiments, the materials discharged from the first crushing system are mixed by using an air flow mixer, and both materials are air path devices, and one air path system can be shared, for example, the air flow discharged from the first crushing system and the air flow mixer is treated by a dust removal and air source treatment system and then is used as a circulating air source to reenter the first crushing system and the air flow mixer for blowing each raw material. And in the embodiment using the air flow mixer, after the raw materials are crushed by the first crushing system, the crushed raw materials are introduced into the air flow mixer through the same induced air pipeline to be mixed. Thus, under the blowing of the air flow, all the raw materials are converged and mixed in the induced air pipeline, then the raw materials are continuously mixed in the air flow mixer, and the air flow sprayed from the bottom of the mixer drives all the raw materials to tumble again, so that all the raw materials are convected, diffused and mixed, and various raw materials which are all in fine particles can be thoroughly and uniformly mixed.

In some embodiments, the raw materials may be separately pulverized, or the raw materials may be grouped according to hardness ranges, the raw materials with similar hardness may be grouped into the same group, and the raw materials of each group may be separately pulverized. Before crushing the raw materials in each group, the raw materials in the same group are mixed, and then the mixture is added into a pneumatic crusher for crushing.

When the raw materials crushed by the first crushing system are introduced into the air flow mixer, the raw materials are converged through the same air introducing pipeline, and the converged mixed raw materials are introduced into the air flow mixer for mixing. The raw materials may be partially mixed during the air crushing, and then subjected to primary mixing in the induced air pipeline and secondary mixing in the air flow mixer.

When the raw materials are grouped according to the hardness level, the raw materials in the same group are primarily mixed before crushing, then the primarily mixed raw materials of the components are added into the same crushing cavity through different crushing paths to be crushed and mixed in the same batch, and then the mixed raw materials are introduced into an air flow mixer through the same air inducing pipeline to be mixed again, and the raw materials are primarily mixed before crushing, mixed in the pipeline and mixed in the air flow mixer to be mixed in multiple stages.

The sintering system may perform the primary sintering of the mixed raw material, or may perform the secondary sintering of the mixed raw material, for example, including a primary sintering device and/or a secondary sintering device. The primary sintering equipment and the secondary sintering equipment can be roller kiln, push plate kiln, rotary kiln, box furnace, tubular furnace and the like.

When the sodium-containing oxide as the sintering product is crushed and sieved, the second crushing system may be used for crushing and sieving, or crushing and sieving may be performed by using crushing equipment such as a jaw crusher, a roller crusher, a hammer crusher, a rod mill, a centrifugal mill, etc.

Taking the second crushing system for crushing and screening as an example, the particle size of the crushed particles containing sodium oxide is controllable and adjustable, so that the layered oxide type sodium-electricity positive electrode material with small particle size can be obtained, and the particle size can be regulated and controlled according to the requirement.

Therefore, in the manufacturing of the positive electrode material of the sodium ion battery, a dry process of gas crushing, gas mixing, sintering and gas crushing screening can be adopted, and the manufacturing system comprises a first gas crushing system, a gas flow mixer, a sintering system and a second gas crushing system, so that on one hand, the process flow is simple, waste water is not required to be discharged, no medium is introduced in the crushed material mixing process, the purity of raw materials is improved, and the purity of products is also improved; in the second aspect, the crushed aggregates and mixed materials with different hardness can be crushed into small particles, the particle size is controllable, the crushed aggregates and mixed materials effect is ensured, the reaction sufficiency during sintering is improved, and the electrochemical performance of the final product, namely the anode material is improved; in the third aspect, the whole manufacturing system can form a closed system, as shown in fig. 2, raw materials after gas crushing and gas mixing are directly connected into closed sintering equipment, and after sintering, the raw materials directly enter a second gas crushing system for gas crushing and screening, so that a finished product can be obtained, and the whole manufacturing system is particularly suitable for products needing to be sintered in a gas environment, and the raw materials and the products are all finished in the closed system. The economical efficiency and the environmental protection can be greatly improved.

In some embodiments, the method for manufacturing a positive electrode material of a sodium ion battery further includes the following: and (3) carrying out dust removal treatment on the air flow discharged in each step, and taking the purified air flow after the dust removal treatment as a circulating air source of the air crushing system for recycling.

Such as: and purifying the gas exhausted by the first crushing system and the gas flow mixer by using the first dust removing system, and taking the purified gas flow at least as a circulating gas source of the first crushing system and the gas flow mixer.

And purifying the gas discharged by the second crushing system by using the second dust removing system, and taking the purified gas flow at least as a circulating gas source of the second crushing system.

Therefore, the air flow can be recycled, the cost is saved, more importantly, the first air crushing system, the air flow mixer and the first dust removing system can form a first closed circulation air path, the second air crushing system and the second dust removing system can form a second closed circulation air path, or all the air crushing and air mixing dust removing systems integrally form a closed circulation air path, the sintering system can also be filled with inert gas or other gases such as oxygen according to the requirements, and the whole manufacturing system can form a closed system.

In some embodiments, the method for manufacturing a positive electrode material of a sodium ion battery further includes the following: and (3) recovering heat from tail gas discharged by the sintering system by using a heat exchange system, and heating a circulating air source for crushing materials by using the recovered heat. When the first crushing system is used for crushing the raw materials and the second crushing system is used for crushing the sodium-containing oxide obtained by sintering, the heat recovered by the heat exchange system is used for heating the air sources of the first crushing system and the second crushing system respectively, such as a preheating air inlet pipeline or an air inlet, or directly heating the air flow. The air flow used for heating crushed aggregates by utilizing the recovered heat can save energy and improve the crushing effect and the mixing effect of materials.

Thus, the manufacturing flow of the positive electrode material of the sodium ion battery can be shown as shown in figure 1, and the positive electrode material has the advantages of economy, environmental protection and the like.

The embodiment of the application also provides a manufacturing system of the sodium ion battery positive electrode material, which can manufacture the sodium ion battery positive electrode material by using the manufacturing method of the sodium ion battery positive electrode material. As shown in fig. 2, the manufacturing system comprises a first crushing system 10, an air flow mixer 20, a sintering system 30 and a dry material crushing and screening system, wherein the first crushing system 10, namely the first crushing system 10 in the embodiment of the method, is provided with a crushing cavity and a crushing path for feeding materials and air flow into the crushing cavity, and is used for crushing each raw material, crushing each raw material into a set particle size, a material outlet 101 is arranged on the crushing cavity, and the materials crushed into the preset size can be discharged from the material outlet 101. The feed inlet of the air flow mixer 20 is connected with the material outlet 101 of the first crushing system 10 through an induced air pipeline, so that crushed materials enter the mixing cavity for mixing, and the crushed materials are uniformly mixed. The sintering system 30 includes a primary sintering device and a secondary sintering device to receive the mixed feed discharged from the air flow mixer 20 and sinter the mixed feed to produce a sodium-containing oxide. The dry material crushing and screening system is used for crushing and screening sodium-containing oxide obtained by sintering. Thus, the manufacturing system manufactures the positive electrode material of the sodium ion battery according to the manufacturing method described in the above embodiment, so as to have the beneficial effects of the manufacturing method described in the above embodiment, and will not be described herein.

In some embodiments, the fabrication system further includes a first dust removal system 40, a second dust removal system 50, and a heat exchange system 70. The first gas source treatment system 80 is arranged at the first gas source treatment system 10, the second gas source treatment system 90 is arranged at the second gas source treatment system 60, the waste gas inlet of the first dust removal system 40 is respectively connected with the exhaust ports of the first gas source treatment system 10 and the gas flow mixer 20, the clean gas outlet is connected with the gas inlet of the first gas source treatment system 80, and the gas outlet of the first gas source treatment system 80 is respectively connected with the gas inlets of the first gas source treatment system 10 and the gas flow mixer 20. In this way, the gas exhausted from the first crushing system 10 and the gas flow mixer 20 is purified, and the purified gas is supplied to the first gas source treatment system 80 through the gas inlet pipeline of the first crushing system 10 to form a circulating gas source, and is continuously supplied to the first crushing system 10 and the gas flow mixer 20, so that the gas flow can be recycled. Similarly, the exhaust gas inlet of the second dust removal system 50 is connected to the exhaust port of the second air pulverizing system 60, the clean gas outlet is connected to the air inlet of the second air source treatment system 90, and the air outlet of the second air source treatment system 90 is connected to the air inlet of the second air pulverizing system 60, so that the purified gas forms a circulating air source. The sintering system 30 may also be provided with an exhaust gas treatment system 100 for purifying exhaust gas discharged from the sintering system. The heat exchange system 70 has a heat recovery line for absorbing heat of the exhaust gas from the sintering system 30, a first heat supply line for supplying heat to the first pulverizing system 10, and a second heat supply line for supplying heat to the second pulverizing system 60, the purge gas exhausted from the first dust removing system 40 may first absorb heat through the first heat supply line and then enter the first gas source processing system 80, and the purge gas exhausted from the second dust removing system 50 may first absorb heat through the second heat supply line and then enter the second gas source processing system 90. In this way, heat in the tail gas discharged from the sintering system 30 is recovered, and the gas used for impacting the material in the first crushing system 10 and the second crushing system 60 is heated respectively, so that the material is crushed by using hot air flow, and a better crushing effect can be achieved.

In some embodiments, as shown in FIG. 2, the first crushing system 10 includes a multiple material crusher 11 for crushing multiple materials of different hardness in a single batch. As shown in fig. 3, the crushing chamber 1 of the multi-material crusher 11 is provided with a material outlet 101 and a classifying wheel 5, and is provided with a first crushing path and/or a second crushing path. The classifying wheel 5 is disposed in the pulverizing chamber 1 and located at the material outlet 101, and as shown in fig. 2, the material outlet 101 is located at the inner side (side closer to the inside of the pulverizing chamber) to control the discharge particle diameter so that the material particles can be discharged through the material outlet 101 after reaching a predetermined size.

In some embodiments, as shown in fig. 3, in the height direction of the crushing cavity, the material outlet 101 is disposed on the top, such as the top wall, of the crushing cavity 1, the classifying wheel 5 may be disposed with at least two groups of particles which are horizontally arranged on two sides of the material outlet 101, the particles meeting the particle size requirement may be discharged through the classifying wheel 5, and the large particles not meeting the particle size requirement may be thrown out by the classifying wheel 5 rotating at a high speed and returned to the crushing cavity 1 for continuous crushing, so that the material particles reach the preset size and then can be ejected through the material outlet 101. By the arrangement, the materials can be discharged from the crushing cavity 1 after meeting the crushing requirement, namely the crushing to the set particle diameter range, and the crushing quality is ensured.

The first crushing path comprises a feed layer and an air inlet layer, the feed layer comprises at least one first material nozzle, and when the first material nozzles are provided with at least two first material nozzles, the first material nozzles are arranged along the circumferential direction of the crushing cavity 1. The first material nozzle 2 is a material inlet for feeding the raw material into the crushing chamber 1, and is connected with a second material feeding member (for example, a screw feeder) for pushing the raw material forward, so as to supply the raw material into the crushing chamber 1. The air intake layer comprises at least two first air flow nozzles 3 arranged circumferentially along the crushing chamber 1. The first air flow nozzle 3 is used to connect with a first air supply assembly (such as an air source and an air pump) to spray high-pressure and high-speed air flow. The axis extension lines of the first air flow nozzles 3 on the same crushing path are converged to the same point. So that high-speed airflows in different directions strike at the same point.

The first material nozzle 2 and the first air flow nozzle 3 are arranged separately, and are fed separately and jet separately. For example, the feed layer is located above the intake layer, i.e. the first material nozzle 2 is arranged above the first gas flow nozzle 3. The raw materials to be crushed are in a falling trend after entering the crushing cavity 1 from the first material nozzle 2, and the air flow sprayed out by the first air flow nozzles 3 arranged in different directions impacts the raw materials and carries the raw materials to the converging point, so that the raw materials in different directions are impacted for the first time to be crushed, and the crushed raw materials are impacted again and for many times under the blowing of the air flow, so that the raw materials can be thoroughly crushed.

The second pulverizing path is a mixed feed layer including at least two combined nozzles 4 arranged along the circumferential direction of the pulverizing chamber 1, and it can be said that a plurality of combined nozzles 4 arranged along the circumferential direction of the pulverizing chamber 1 in the same height region form a second pulverizing path for mixing and injecting a high-speed air stream and a raw material to be pulverized.

The combination nozzle 4 includes a nozzle body 41, and a discharge passage and an air outlet passage are formed in the nozzle body 41, the discharge passage forming a second material nozzle 42, and the air outlet passage forming a second air flow nozzle 43. The second material nozzle 42 is connected to the second material supply member to supply the raw material into the pulverizing chamber, and the second air flow nozzle 43 is connected to the second air supply assembly to spray the high-pressure high-speed air flow. Thus, the combination nozzle 4 integrates a discharge port and an air outlet port. At the same time, the second material nozzle 42 is nested or otherwise brought close to the second gas flow nozzle 43. When the two air flow nozzles are sleeved, the second air flow nozzle 43 is positioned in the discharging channel, namely in the spray cavity of the second material nozzle 42, or the second material nozzle 42 is positioned in the second air flow nozzle 43. When being closed, the second air flow nozzle 43 is positioned beside the second material nozzle 42, and the two nozzles are closed along the direction approaching the nozzle. When the two air flow nozzles are sleeved, the axes of the second air flow nozzle 43 and the second air flow nozzle 42 can be parallel or coincident, and can also have an included angle. When being closed, the axes of the second air flow nozzle 43 and the second material nozzle 42 are provided with clamps, and the ejected air flow and the raw material are gradually closed. On the same crushing path, the axis extension lines of all the second air flow nozzles 43 on each combined nozzle 4 are converged to the same point, so that the air flows in different directions collide at the convergence point.

When the second air flow nozzle 43 sprays high-speed high-pressure air flow, the air flow moving at high speed drives the surrounding air to flow, so that the high-speed high-pressure air flow sprayed by the second air flow nozzle 43 forms a suction area at the nozzle 433 of the air flow, and can absorb and clamp the raw material provided by the second material nozzle 42, so that the raw material moves forward at high speed, kinetic energy is given to the raw material, the raw material is obviously accelerated and moves at high speed, and the speed of the raw material entering the crushing cavity 1 is obviously improved. When the combined nozzles 4 in different directions spray out air flow and raw materials, the raw materials in different directions can collide violently at the converging points, so that the collision strength between the raw materials is obviously enhanced, the raw materials can be more violently collided, the raw materials can be rapidly and forcefully crushed, and the crushing effect is improved. Therefore, the raw materials are sprayed out due to the structural characteristics of the combined nozzle 4, the initial speed of the raw materials entering the crushing cavity 1 is increased, the incoming materials in different directions are impacted more severely and more strongly, and the crushing effect is improved. The second crushing path has stronger crushing strength compared with the first crushing path, can achieve good crushing effect when crushing materials with higher hardness, and has short time and high efficiency.

Meanwhile, in the height direction, the raw materials entering from the lower crushing path are subjected to the impact of the air flow nozzle at the higher position and then subjected to the stronger impact again in the process of moving upwards to be close to the material outlet 101 after being crushed, and compared with the raw materials entering the crushing cavity 1 from the higher crushing path, the raw materials enter from the higher position and are subjected to stronger impact, and the crushing force is larger. The crushing path at the lower position has larger crushing force compared with the crushing path at the higher position, so that the raw materials can be impacted more strongly. Then, in the height direction of the pulverizing chamber 1, a plurality of pulverizing paths having different pulverizing forces may be formed, and each raw material having different hardness may be pulverized by selecting a pulverizing path of a corresponding level according to the hardness level.

And the crushing chamber 1 is provided with a first crushing path and/or a second crushing path. Therefore, the pulverizing paths of different forces in the plurality of layers on the pulverizing chamber 1 may be formed by a plurality of first pulverizing paths arranged in the height direction, a plurality of second pulverizing paths arranged in the height direction, or at least one first pulverizing path and at least one second pulverizing path.

For example, in some embodiments, only the first crushing paths are provided on the crushing cavity 1, and the first crushing paths are provided with at least two layers, and are arranged along the height direction of the crushing cavity 1, so that the crushing force of each first crushing path gradually increases from top to bottom along the height direction, and the crushing force can be used for crushing raw materials with different hardness grades.

In some embodiments, only the second pulverizing path is provided on the pulverizing chamber 1, and the second pulverizing path is provided with at least two layers and is arranged in the height direction of the pulverizing chamber 1. The crushing force of each second crushing path is gradually increased from top to bottom along the height direction, so that a plurality of crushing paths with different crushing forces are formed, and the crushing paths can be used for crushing raw materials with different hardness levels.

In some embodiments, when the first crushing path and the second crushing path are only one layer, the second crushing path may be disposed below the first crushing path, so that the raw material entering from the second crushing path is impacted by the first airflow nozzle 3 in the process of approaching the material outlet 101, and the crushing effect is better.

In still other embodiments, the first pulverizing paths may be provided with at least two layers, the second pulverizing paths may be provided with at least two layers, each pulverizing path is arranged in sequence in the height direction, and each second pulverizing path is located below all the first pulverizing paths. Thus, each pulverizing path arranged from high to low has a pulverizing strength gradually increasing from low to high. When crushing a plurality of raw materials with different hardness ranges, grouping the raw materials according to the hardness level, arranging the raw materials of each component according to the hardness level, and adding the raw materials into an adaptive crushing path. For example, the hardest feedstock set is added to the lowest second comminution path and the least hard feedstock set is added to the highest first comminution path.

The multi-material pulverizer 11 may be used for pulverizing materials with different hardness in the same batch, for example, a first pulverizing path with a higher position, which is used for pulverizing materials with smaller hardness, a first pulverizing path with a lower position, or a second pulverizing path with a lower position, which is formed by the combined nozzle 4, which is used for pulverizing materials with larger hardness, and since the combined nozzle 4 can make the materials jet out with high speed and impact, the pulverizing effect of the materials is improved, the multi-material pulverizer not only can be used for pulverizing the materials with larger hardness, but also shortens the pulverizing time period of the materials with larger hardness, and the pulverizing time period of the materials with larger hardness can also quickly reach the pulverizing requirement, so that when the pulverizer pulverizes the materials with different hardness in the same batch, the multiple materials with different hardness can be well pulverized and mixed in the same pulverizing cavity 1, the time period used for pulverizing the preset size is basically the same, the materials can be discharged from the multi-material pulverizer 11 through the material outlet 101 in the initial mixing state and enter the air flow mixer 20 for upgrading and mixing, and the pulverizing mixing efficiency of the multiple materials is remarkably improved.

Of course, besides the arrangement position, the pulverizing force of the second pulverizing path can be adjusted by adjusting the air jet speed, the jet quantity and the like of each layer of air jet nozzles, for example, on the combined nozzle 4 in the second pulverizing path, the second air jet nozzles 43 can have different pulverizing forces relative to the second material nozzles 42 due to different numbers and angles of the second air jet nozzles, so that each layer of second pulverizing path on the multi-material pulverizer 11 has different pulverizing strength, is controllable and adjustable, can be used for rapidly pulverizing multiple raw materials with different hardness in the same batch according to requirements, and enables the raw materials to be primarily mixed so as to enhance the electrochemical performance of the finally obtained anode material.

For example, in some embodiments, in the combined nozzle 4, the second air flow nozzle 43 and the second material nozzle 42 are sleeved on the nozzle body 41, and the second air flow nozzle 43 may be sleeved on the second material nozzle 42, that is, sleeved outside the second material nozzle 42, or the second material nozzle 42 may be sleeved outside the second air flow nozzle. In this way, a second material nozzle 42 and a second air flow nozzle 43 are integrated in a combined nozzle 4, which can accelerate the raw material during spraying, with a greater crushing strength than the first crushing path.

In some embodiments, in the combined nozzle 4, the second air flow nozzle 43 and the second material nozzle 42 are close together on the nozzle body 41. For example, as shown in fig. 4 and 5, the second air flow nozzle 43 is nested on the nozzle body 41 and located beside the second material nozzle 42 (i.e., the discharge passage on the nozzle body 41). Meanwhile, the second air flow nozzle 43 is inclined gradually closer to the axis of the second material nozzle 42, i.e., in a direction gradually closer to the axis of the second material nozzle 42, from the air inlet end to the air outlet end of the second air flow nozzle 43, i.e., gradually closer to the spout 433. It can be said that the distance from the inlet end of the second air flow nozzle 43 to the axis of the second material nozzle 42 is larger than the distance from the spout 433 of the second air flow nozzle 43 to the axis of the second material nozzle 42. The flow path of the high-speed air flow ejected from the second air flow nozzle 43 is inclined with respect to the axis of the second material nozzle 42 (i.e., the direction of the incoming material with higher hardness and the original moving path), on the one hand, compared with the parallel axes, the suction acceleration area formed by the high-speed air flow is increased, so that more raw materials with higher hardness can be adsorbed, the acceleration path and time of the raw materials with higher hardness can be prolonged, more kinetic energy can be given to the raw materials with higher hardness, the collision between the raw materials with higher hardness is more severe, and the crushing effect is enhanced; on the other hand, the high-speed air flow ejected from the second air flow nozzle 43 gathers toward the central axis direction of the second air flow nozzle 42, so that the raw materials with higher hardness are gathered without blowing off, more raw materials with higher hardness gather and are ejected into the crushing cavity 1 after being accelerated, and the raw materials with higher hardness ejected from the combined nozzle 4 in other directions collide strongly; therefore, the crushing effect and the crushing efficiency of the raw materials with higher hardness are improved in terms of the moving speed, the impact degree, the adsorption gathering effect and the like of the raw materials with higher hardness, so that the raw materials with higher hardness can be crushed in the same batch with the materials with lower hardness. The combined nozzle 4 in this embodiment also constitutes a second comminution path with a higher comminution force.

Further, when the second airflow nozzle 43 is located beside the second material nozzle 42, the nozzle 433 may be aligned with the outlet of the second material nozzle 42, or may be located outside the outlet of the second material nozzle 42 beyond the outlet of the second material nozzle 42. In the embodiment shown in the drawings, the outlet 433 of the second air flow nozzle 43 is beyond the outlet of the second air flow nozzle 42 and is located outside the second air flow nozzle 42, and the suction acceleration area formed by the high-speed air flow at the outlet 433 is partially located inside the second air flow nozzle 42 and partially located outside the second air flow nozzle 42, i.e., inside the pulverizing chamber 1. Not only can the incoming material in the second material nozzle 42 be accelerated, but also the adsorption acceleration can be performed on the material already positioned in the crushing cavity 1, namely the material which has generated the first collision, so that the probability of the secondary collision of the partial material is increased, and the crushing effect of the material and the crushing strength of the crushing path are also enhanced.

On the other hand, the second air flow nozzles 43 may be provided with one or more (plural means two or more) on the same combined nozzle 4. When the second air flow nozzles 43 are provided with at least two, the number of the second air flow nozzles 43 increases, the formed acceleration area increases, and more of the raw materials with higher hardness provided by the second air flow nozzles 42 can be adsorbed and accelerated, increasing the pulverizing strength. When at least two second air flow nozzles 43 are provided, they may be provided side by side, may be provided opposite to each other, or may be provided around the second material nozzle 42. Wherein in particular a plurality of second air flow nozzles 43 surround the second material nozzles 42 with a greater pulverizing force.

For example, at least two second air flow nozzles 43 are arranged on the nozzle body 41 in the circumferential direction of the discharge passage, i.e., the second material nozzle 42, as shown in fig. 4, 3 second air flow nozzles 43 are arranged around the center axis of the second material nozzle 42 in the drawing, and each nozzle 433 is drawn toward the center axis of the second material nozzle 42. The central space enclosed by each second air flow nozzle 43 is also coincident with the axial direction of the second air flow nozzle 42 in the discharge direction. After the high-speed air flows are sprayed out from the spray nozzles 433, the high-speed air flows are gradually gathered, and a strong negative pressure area is formed in the discharging direction of the second material nozzle 42. The negative pressure region coincides with the flow path of the higher hardness feedstock. The higher hardness material is strongly adsorbed in the second material nozzle 42, such as adjacent to the nozzle 433, due to the negative pressure formed by the aggregation and encapsulation of the high speed air flow, so as to significantly accelerate the forward movement and spray at high speed, as shown by the arrow in fig. 6. So set up, combination nozzle 4 not only can adsorb more higher raw materials of hardness, accelerates for more higher raw materials of hardness, and acceleration effect is stronger, and because each spout 433 all faces same direction, the higher raw materials of absorptive hardness can gather together for the raw materials is accelerated and is gathered together the effect and all further improves, compares with the acceleration of single second air current nozzle 43, can further improve the impact dynamics of the higher raw materials of hardness, thereby further improves crushing dynamics.

While in the preferred embodiment each second air flow nozzle 43 is disposed about the central axis of the second material nozzle 42 with its converging point of the axis extension being located on the axis or axis extension of the second material nozzle 42, as shown in fig. 6. The axis extension lines of the combined nozzles 4 in the same pulverizing path are all converged to the same point, that is, the axes of the second material nozzles 42 and the second air flow nozzles 43 in the same pulverizing path are all converged to the same point. Thus, the gathering effect of the raw materials with higher hardness is better, the movement is smoother, the speed is better improved, the impact force is larger, and the crushing force is larger.

As can be seen from the above-mentioned structural embodiment of the combined nozzle 4, the number and arrangement of the second air flow nozzles 43 on the combined nozzle 4 can be controlled, so that the different second pulverizing paths have increasing pulverizing forces. The factors influencing the crushing strength of the second crushing path include the speed and the angle of the air flow ejected by the second air flow nozzles 43 on the combined nozzle 4 in addition to the number and the arrangement of the second air flow nozzles 43.

First, the angular adjustment will be described.

In some embodiments, the nozzle body 41 of the combined nozzle 4 is provided with a discharge channel and a plurality of air outlet channels. Each of the outlet channels forms a second air flow nozzle 43. The combined nozzles 4 are multiple, and the combined nozzles 4 have multiple specifications, and the included angles of the air outlet channel and the discharging channel are different on the combined nozzles 4 with different specifications. In this way, the angle of the second air flow nozzle 43 to the second material nozzle 42 may be altered.

Alternatively, in some embodiments, the second gas flow nozzle 43 and/or the nozzle body 41 can be replaced to adjust the included angle of the second gas flow nozzle 43 and the second material nozzle 42.

For example, the nozzle body 41 is provided with a discharge passage forming the second material nozzle 42, and is connected to the mounting plate 44. Meanwhile, the second air flow nozzle 43 is a tube or a cylinder, and is connected to the nozzle body 41 or to the mounting plate 44, and the nozzle body 41 has a mounting hole into which the second air flow nozzle 43 is inserted. The second air flow nozzle 43 extends into the mounting hole and is connected to the nozzle body 41 or the mounting plate 44. The combination nozzle 4 is mounted on the inner wall of the pulverizing chamber 1 by a mounting plate 44.

Meanwhile, the second air flow nozzles 43 are detachably connected with the nozzle body 41 or the mounting plate 44, and the second air flow nozzles 43 are provided with various specifications, and the second air flow nozzles 43 of different specifications have different inclination angles. When the second air flow nozzles 43 of different specifications are mounted on the nozzle body 41 or the mounting plate 44, the second air flow nozzles 42 form different degrees of included angles with each other. In this way, the spray angle of the air flow with respect to the axis of the second material air flow nozzle 42 can be adjusted by replacing the second air flow nozzle 43.

Alternatively, the second air flow nozzle 43 is detachably connected to the nozzle body 41 or the mounting plate 44, and the nozzle body 41 is also detachably connected to the mounting plate 44. And the nozzle body 41 is provided with a plurality of specifications, and the included angle between the axis of the mounting hole on the nozzle body 41 of the plurality of specifications and the axis of the second material nozzle 42 is gradually increased, and the increase and the change are presented.

In this way, in the combination nozzle 4, by changing the nozzle body 41 and/or the second air flow nozzle 43 of different specifications, the inclination angle of the second air flow nozzle 43 with respect to the second material nozzle 42 can be adjusted. When the raw materials with different types and different hardness are crushed, the specification of the combined nozzle 4 can be adjusted by changing the nozzle body 41 or the second air flow nozzle 43 according to the requirements, the included angle between the second air flow nozzle 43 and the second material nozzle 42 is changed, the angle of the sprayed air flow, the convergence point of each air flow and the like are changed, so that the length of an acceleration path for conveying the raw materials is changed, the impact force between the raw materials is changed, the crushing force is adjusted, and different crushing requirements are realized.

It can be seen that, in the second pulverizing path provided in this embodiment, the combined nozzles 4 have different specifications, and the inclination angle of the second air flow nozzle 43 relative to the second material nozzle 42 can be changed by exchanging components, so that the impact degree of the high-hardness material can be adjusted according to the requirements to meet different pulverizing requirements.

When the inclination angle of the second air flow nozzle 43 with respect to the second material nozzle 42 is changed by changing the nozzle body 41, since the cost of the nozzle body 41 mainly for feeding and for fixing the second air flow nozzle 43 is lower than the cost of the second air flow nozzle 43 required to eject high-pressure high-speed air flow, the angle of the second air flow nozzle 43 and the second material nozzle 42 can be changed by changing the nozzle body 41, enabling cost saving.

The nozzle body 41 and the mounting plate 44 may be detachably connected by a threaded connection, by a fastener, or by a detachable connection such as a snap-fit structure. The second air flow nozzle 43 may be detachably connected to the nozzle body 41 by a screw connection or by a detachable connection such as a snap connection. So arranged, it is convenient to separate the nozzle body 41 and the second air flow nozzle 43, and replace them as needed.

In addition to adjusting the angle between the second air flow nozzles 43 and the second air flow nozzles 42 by replacing the nozzle bodies 41, the number of the second air flow nozzles 43 mounted on the same nozzle body 41 may be adjusted by replacing the nozzle bodies 41 of different specifications. For example, the second air flow nozzle 43 is detachably connected to the nozzle body 41 or the mounting plate 44, and the nozzle body 41 is also detachably connected to the mounting plate 44, and the nozzle body 41 is provided with a plurality of specifications, and the number of mounting holes in the nozzle body 41 of the plurality of specifications is gradually increased, presenting an increased variation. The number of the second air flow nozzles 43 on the same combined nozzle 4 can be adjusted by replacing the nozzle bodies 41 with different specifications, and the number of the second air flow nozzles 43 matched with the same second material nozzle 42 can be adjusted. So, also can change the dynamics of smashing to the raw materials, satisfy different crushing demands.

The regulation of the air flow jet velocity will be described below.

In some embodiments, the first air flow nozzle 3 and/or the second air flow nozzle 43 are tubular bodies and are all raval tubes, or, alternatively, the lumen structure is a raval tube structure. Taking the second air flow nozzle 43 as an example, as shown in fig. 5, the lumen includes a wide diameter section 431 and a narrow diameter section 432, the narrow diameter section 432 is located between the wide diameter section 431 and the spout 433, and the diameter is smaller than that of the wide diameter section 431. While spout 433 is flared with a diameter greater than the diameter of narrow diameter section 432. By such arrangement, the high-pressure air flow supplied to the air supply assembly can be further accelerated by the diameter reduction, and after the diameter reduction, the air flow rate can be further increased by expanding and spraying (Laval pipe principle in the prior art). The first air flow nozzle 3 and/or the second air flow nozzle 43 having this structure (the first diameter-reduced and the second diameter-enlarged ejection structure) may be also called a laval nozzle.

Therefore, in this embodiment, by providing the first air flow nozzle 3 and/or the second air flow nozzle 43 as the laval nozzle, the flow velocity of the air flow is further increased by utilizing the structural feature, the speed of the air flow injected into the pulverizing cavity 1 is increased, the blowing action on the raw material is enhanced, the impact pulverizing effect of the raw material can be enhanced, and the pulverizing force of the pulverizing path is enhanced.

As can be seen from the above embodiments, the pulverizing forces of the pulverizing paths are not only affected by the height position, but also different pulverizing forces of the second pulverizing paths can be achieved by adjusting the structure of the combined nozzle 4, and the pulverizing paths can be set on the whole multi-material pulverizer 11 according to the requirements, so that the high-efficiency multi-material pulverizing can be ensured, and the raw materials with different hardness can be ensured to be pulverized to the required granularity, so that the raw materials with different hardness can be mixed more thoroughly and uniformly, and the sintering reaction is more complete, thereby improving the electrochemical performance of the obtained anode material.

Of course, in other embodiments, the first air crushing system 10 may also include a plurality of single-material air crushers, where the crushing cavity of the single-material air crushers is provided with one of the first crushing path and the second crushing path, and the material outlets 101 of the plurality of single-material air crushers are all communicated with the feed inlet of the air flow mixer 20, so that the raw materials may be crushed individually, or may be crushed independently in groups in different air crushers.

In still other embodiments, the first crushing system 10 may also include a crusher having a plurality of independent crushing chambers, where the independent crushing chambers are provided with a first crushing path or a second crushing path, and the material outlets 101 of the crushing chambers are converged on the same pipeline, such as an induced air pipeline, and are connected to the airflow mixer 20 through the induced air pipeline. Thus, the raw materials are singly crushed in different crushing cavities, but the raw materials can be subjected to primary mixing before entering a mixer after being discharged.

The first crushing system 10 may further include a plurality of single-material air crushers, where the crushing chambers of the single-material air crushers are provided with one of the first crushing path and the second crushing path, and the crushing chambers of the plurality of single-material air crushers are communicated, so that the raw materials may be crushed and mixed simultaneously, which is equivalent to primary mixing, and then enter the induced air pipeline to perform secondary mixing, and enter the air flow mixer 20 to perform tertiary mixing, so as to form tertiary mixing.

In still other embodiments, the first crushing system 10 is a multi-stage crushing system, for example, the multi-stage crushing system comprises a plurality of multi-material crushers 11, the plurality of multi-material crushers 11 are sequentially connected to form the multi-stage crushing system, and raw materials are sequentially fed into the multi-material crushers 11 for crushing, so that multi-stage crushing is realized, and crushing and mixing effects are better.

One specific example of the production is shown below.

Production example 1

Sodium carbonate, ferric oxide, nickel oxide and manganese oxide are mixed according to the mole ratio of 1.1: weighing the materials according to the ratio of 0.15:0.8:0.05, and adding the materials into different feed inlets of the multi-material pulverizer respectively (namely adding the materials through different pulverizing paths). Wherein nickel oxide (mohs hardness of 7.5) and ferric oxide (mohs hardness of 6.5) are added to the second pulverizing path of the multi-material pulverizer, the number of collisions is increased, and manganese dioxide (mohs hardness of 5) and sodium carbonate (mohs hardness of 4) are added to the first pulverizing path, and the rotation speed of the classifier wheel is set to 15000rpm. After crushing, the raw materials subjected to preliminary mixing are introduced into an air flow mixer through a material outlet 101, the air source pressure of the air flow mixer is regulated to be 0.8MPa, the pulse interval is 5s, and the mixing time is 5min. The mixed raw materials are obtained at the discharge port of the airflow mixer and are directly introduced into the box-type furnace. And (3) sintering at 700 ℃ for 20 hours to obtain sodium-containing oxide, introducing the sodium-containing oxide into a gas crusher of a second gas crushing system, and crushing to obtain the layered oxide type sodium-electricity anode material. The particle size of the positive electrode material is between 1 and 5 mu m.

Preparation example 2

Sodium carbonate, ferric oxide, nickel oxide and manganese oxide are mixed according to the mole ratio of 1.1: after being weighed according to the ratio of 0.15:0.8:0.05, the materials are respectively added into four independent single-material air crushers, and the material outlets 101 of the four single-material air crushers are converged into a total outlet. The main outlet is connected with the feed inlet of the airflow mixer through an induced air pipeline. The crushed raw material is thus fed into a gas flow mixer. The subsequent steps and settings of the program, sintering time, sintering temperature, and the like were the same as those of production example 1.

Production example 3

Weighing sodium carbonate, nickel oxide and manganese oxide according to the molar ratio of 1.1:0.8:0.2, and respectively adding the sodium carbonate, the nickel oxide and the manganese oxide into different feed inlets of a multi-material pulverizer. Wherein, nickel oxide is added into the lower feed inlet of the multi-material pulverizer, namely the second pulverizing path, and sodium carbonate and manganese oxide are added into the upper feed inlet, namely the first pulverizing path. The subsequent steps and settings of the program, sintering time, sintering temperature, and the like were the same as those of production example 1.

Preparation example 4

Sodium carbonate and ferric oxide are weighed according to the mol ratio of 1.1:1 and then are respectively added into different feed inlets of the multi-material pulverizer. Wherein, ferric oxide is added into a lower feed port of the multi-material pulverizer, such as a second pulverizing path, and sodium carbonate is added into an upper feed port of the multi-material pulverizer, such as a first pulverizing path. The subsequent steps and settings of the program, sintering time, sintering temperature, and the like were the same as those of production example 1.

Production example 5

Sodium carbonate, ferric oxide, nickel oxide, manganese oxide, copper oxide and zinc oxide are mixed according to the mole ratio of 1.1:0.3:0.3:0.3:0.1: and 0.01 is weighed and then is added into different feed inlets of the multi-material pulverizer respectively. Wherein sodium carbonate, copper oxide, zinc oxide and manganese oxide are added to an upper feed port such as a first pulverizing path, and iron oxide and nickel oxide are added to a lower feed port such as a second pulverizing path. The subsequent steps and settings of the program, sintering time, sintering temperature, and the like were the same as those of production example 1.

The performance comparisons of the three sets of examples are made below.

Test example 1

Preparing a positive electrode material: the positive electrode material was prepared in accordance with the above-described production example 1, and the resultant positive electrode material was designated as product 1.

Preparing an electrode: mixing the product 1 with polyvinylidene fluoride and conductive carbon black in the ratio of 8:1:1; adding a certain amount of N-methyl pyrrolidone solvent, and fully and uniformly stirring the obtained mixture by using a mechanical centrifugal stirrer to obtain slurry. The slurry is uniformly coated on an aluminum foil through a coating machine, and then is placed in a 100 ℃ oven for vacuum drying for 12 hours. Subsequently, the dried pole piece was cut into a circular pole piece having a diameter of 12mm, and weighed, and the mass of the active material on the circular pole piece was calculated to be about 5mg.

Electrochemical performance test: all cell assemblies were completed in a glove box (water oxygen values all below 0.01 ppm). The constant current charge and discharge test and the long-cycle test of the button cell are realized by a New Wei CT4008 charge and discharge tester, and the test voltage window is 2-4.2V.

Comparative example 1

Preparing a positive electrode material: the same raw materials as in comparative example 1 were used, but the raw materials were not pulverized, and were mixed only by using an air flow mixer, and the subsequent steps and settings such as mixing time, sintering temperature, etc., were the same as in production example 1. The final product was designated product 2.

Preparing an electrode: product 2 was mixed with polyvinylidene fluoride and conductive carbon black in the same mixing ratio as in test example 1.

Electrochemical performance test: the same as in test example 1.

Comparative example 2

Preparing a positive electrode material: the raw materials are mixed and dried by using wet granulation in the prior art, and a sintering precursor is obtained, wherein the specific wet granulation process is as follows: sodium carbonate, ferric oxide, nickel oxide and manganese oxide are mixed according to the mole ratio of 1.1:0.15:0.8:0.05, and the solid content was 20%. The mixture is circularly sanded for 90 minutes in a sand mill, and stable and uniformly dispersed slurry is obtained. Pumping the slurry into a spray dryer, controlling the air inlet temperature to be 250 ℃, controlling the outlet temperature to be 100 ℃ and the feeding speed to be 300mL/min, thus obtaining the dried sintering precursor. The subsequent steps and settings of the program, sintering time, sintering temperature, and the like were the same as those of production example 1.

Preparing an electrode: product 3 was mixed with polyvinylidene fluoride and conductive carbon black in the same mixing ratio as in test example 1.

Electrochemical performance test: the same as in test example 1.

XRD patterns of the product 1 in test example 1 and the product 2 in comparative example 1 will be compared as shown in fig. 8. The product 1 of test example 1 can be demonstrated to conform to the characteristic peaks of the O3 type layered sodium-electric positive electrode material. While the product 2 of comparative example 1 (having the same raw material and sintering process as in test example 1) exhibited not only characteristic peaks of the O3 type layered sodium-electric positive electrode material but also characteristic peaks of NiO, it was revealed that in comparative example 1, niO in the raw material did not completely migrate to the inside of the crystal lattice of the product 2. The fusion rate of elements in the raw materials is low, and the performance of the product 2 is low.

Therefore, in the present application, it can be also demonstrated that the first pulverizing system is used for pulverizing each raw material, and the particle size of the pulverized raw material is controlled, so that the mixing thoroughly degree of each raw material can be improved, the sufficiency of the sintering reaction of each raw material is enhanced, and the performance of the final product, namely the prepared positive electrode material is improved.

The charge and discharge test results of the batteries of test example 1, comparative example 1 and comparative example 2 were compared as shown in fig. 9. At a discharge rate of 1C, product 1 had a specific capacity (specific capacity refers to a discharge capacity of 1 per gram of product) of more than 95.34mAh/g, and after 80 charge-discharge cycles, product 1 had a specific capacity of 81.56mAh/g, and a cycle capacity maintenance rate as high as 85.5%, which were significantly higher than those of the active materials in comparative examples 1 and 2.

The basic principles of the present application have been described above in connection with specific embodiments, however, it should be noted that the advantages, benefits, effects, etc. mentioned in the present application are merely examples and not limiting, and these advantages, benefits, effects, etc. are not to be considered as necessarily possessed by the various embodiments of the present application. Furthermore, the specific details disclosed herein are for purposes of illustration and understanding only, and are not intended to be limiting, as the application is not intended to be limited to the details disclosed herein as such.

Claims

1. The manufacturing method of the positive electrode material of the sodium ion battery is characterized by comprising the following steps of:

2. The method for manufacturing a positive electrode material for a sodium ion battery according to claim 1, wherein the step of pulverizing the raw materials to a predetermined particle size using a first pulverizing system comprises the steps of:

3. The method for manufacturing a positive electrode material of a sodium ion battery according to claim 1, wherein the dry material mixing device comprises an air flow mixer; and/or the dry material crushing and screening system is a second air crushing system.

4. The method for manufacturing a positive electrode material for a sodium ion battery according to claim 3, further comprising: introducing all the crushed raw materials of the first crushing system into the airflow mixer by using the same induced air pipeline, so that all the crushed raw materials are subjected to primary mixing in the induced air pipeline, and secondary mixing in the airflow mixer.

5. The method for manufacturing a positive electrode material for a sodium ion battery according to claim 1 or 3, further comprising: and (3) carrying out dust removal treatment on the air flow discharged in each step, and taking the purified air flow after the dust removal treatment as a circulating air source for recycling.

6. The method of manufacturing a positive electrode material for a sodium ion battery according to claim 1, further comprising recovering heat from exhaust gas discharged from the sintering system by using a heat exchange system, and heating a circulating gas source for pulverizing materials by using the recovered heat.

7. The method for manufacturing a positive electrode material of a sodium ion battery according to claim 1, wherein the compound raw materials comprise an iron source, a manganese source, a nickel source and doping elements, and the molar ratio of the elements of the sodium source, the iron source, the manganese source, the nickel source and the doping elements is 1-1.1:0.2-0.9:0.05-0.9:0.1-0.9: 0-0.1; wherein the molar ratio of the sodium source to the elements of the compound raw material is 1-1.1:1.

8. The method for manufacturing a positive electrode material of a sodium ion battery according to claim 7, wherein the sodium source is one or more of sodium carbonate, sodium dihydrogen phosphate, sodium sulfate, sodium nitrate, sodium hydroxide, sodium acetate and sodium oxalate, and the manganese source is one or more of manganese dioxide, manganous oxide, manganese oxalate, manganese sulfate, manganese carbonate and manganese nitrate; the nickel source is one or more of nickel sulfate, nickel nitrate, nickel monoxide, nickel oxide and nickel hydroxide; the iron source is ferric oxide, ferric sulfate, ferric hydroxide and ferric oxide; the doping element is one or more of copper, titanium, magnesium, vanadium, niobium, lithium, aluminum, tungsten, molybdenum, chromium, silicon, strontium, zirconium, boron, zinc and calcium.

9. The method for manufacturing a positive electrode material of a sodium ion battery according to claim 1, wherein when the mixed raw materials are sintered in a gas environment by using a sintering system, the sintering temperature is 500-1200 ℃ and the sintering time is 8-24 hours;

10. The method of manufacturing a positive electrode material for a sodium ion battery according to claim 1, wherein the first crushing system comprises at least one multi-material crusher or a plurality of single-material crushers, and at least two layers of crushing paths are arranged on the multi-material crusher along the height direction of the crushing cavity.

11. A sodium ion battery positive electrode material manufacturing system, comprising:

a first crushing system having a crushing chamber and a crushing path for feeding material and air flow into the crushing chamber for crushing the raw material;

the air flow mixer is connected with a material outlet of the first crushing system through an induced air pipeline so as to mix crushed raw materials;

The sintering system comprises primary sintering equipment and/or secondary sintering equipment, and is used for receiving the mixed raw materials discharged by the airflow mixer and sintering the mixed raw materials;

and the dry material crushing and screening system is used for crushing and screening the products of the sintering system.

12. The sodium ion battery positive electrode material production system of claim 11, wherein the dry material crushing and screening system comprises a second air crushing system for crushing sodium-containing oxides, the production system further comprising:

the first dust removal system is characterized in that an exhaust gas inlet is respectively connected with the first air crushing system and an exhaust port of the air flow mixer, and a clean gas outlet is connected with an air inlet of the first air crushing system;

the waste gas inlet of the second dust removing system is connected with the exhaust port of the second air crushing system, and the clean gas outlet of the second dust removing system is connected with the air inlet of the second air crushing system;

the heat exchange system is provided with a heat return pipeline for absorbing the heat of the exhaust gas of the sintering system, a first heat supply pipeline for supplying the heat to the first crushing system and a second heat supply pipeline for supplying the heat to the second crushing system.

13. The positive electrode material manufacturing system of a sodium ion battery according to claim 11, wherein the first crushing system comprises a multi-material crusher, wherein a crushing cavity of the multi-material crusher is provided with a material outlet, a classification wheel, and a first crushing path and/or a second crushing path;

The first crushing path comprises a feeding layer and an air inlet layer, the feeding layer comprises at least one first material nozzle, and the air inlet layer comprises at least two first air flow nozzles which are circumferentially arranged along the crushing cavity;

the second crushing path is a mixed material layer, at least one layer is arranged in the height direction and comprises at least two combined nozzles which are circumferentially arranged along the crushing cavity, a second airflow nozzle and a second material nozzle are formed on a nozzle main body of the combined nozzle, wherein the second material nozzle and the second airflow nozzle are sleeved, or the second airflow nozzle and the second material nozzle are close to each other along the direction close to the nozzle;

the classifying wheel is positioned in the crushing cavity and arranged at the material outlet so that the material particles reach the preset size and are sprayed out through the material outlet.

14. The positive electrode material manufacturing system of a sodium ion battery according to claim 13, wherein at least two second air flow nozzles are provided on the same combined nozzle, at least two second air flow nozzles are arranged around the second material nozzle along the circumferential direction of the second material nozzle, and extension lines of axes of the second air flow nozzles converge to the same point.

15. The positive electrode material manufacturing system of a sodium ion battery according to claim 13, wherein the material outlet is opened at the top in the height direction of the crushing chamber, at least two layers are provided in the first crushing path and/or the second crushing path, and each of the second crushing paths is located below all of the first crushing paths.