System for producing ternary positive electrode material

Abstract

The utility model belongs to the field of lithium ion battery positive electrode materials, and relates to a system for producing a ternary positive electrode material. Comprising feeding equipment, primary sintering equipment, crushing equipment, primary iron removal equipment, a primary auxiliary material adding device, washing equipment, solid-liquid separation equipment, drying equipment, a secondary auxiliary material adding device, secondary sintering equipment and secondary iron removal equipment which are connected in sequence. The device is high in automation degree and production efficiency and low in production cost, produced products are good in consistency, and the modified ternary positive electrode material can effectively improve electrolyte decomposition, improve battery efficiency and prolong the service life of a battery.

Description

Technical Field

[0001] This utility model belongs to the field of lithium-ion battery cathode materials, and relates to a system for producing ternary cathode materials. Background Technology

[0002] High nickel content is a major trend in the development of ternary cathode materials. From an electronic structure perspective, cobalt (Co) has empty eg orbitals, while its t2g orbitals largely overlap with the 2p orbitals of oxygen (O), making it prone to oxygen evolution and structural collapse during deep delithiation. Furthermore, the t2g orbitals of cobalt form π bonds with the 2p orbitals of oxygen, which are relatively weak and facilitate electron transfer. Nickel (Ni) has very little overlap between its eg orbitals and the 2p orbitals of oxygen. For manganese, when the nickel content exceeds that of manganese, manganese will exist in a tetravalent state, which is very stable. Theoretically, electrons in the eg orbitals of nickel can be completely lost, resulting in higher effective capacity for lithium nickel oxide. Therefore, in the NCM system, higher nickel content leads to higher energy density and specific capacity.

[0003] The prior art CN 116706048 A discloses a nickel-cobalt-manganese ternary cathode material, its preparation method, and a lithium-ion battery. The nickel-cobalt-manganese ternary cathode material has a secondary particle structure, with the primary particles having a needle-like morphology and a grain size of 100-200 nm, arranged radially and closely. The preparation method includes the following steps: (1) using a co-precipitation method to obtain a nickel-cobalt-manganese hydroxide precursor; (2) mixing the nickel-cobalt-manganese hydroxide precursor with a lithium source and dopants and sintering to obtain intermediate product A; (3) mixing intermediate product A with a coating material and sintering to obtain intermediate product B; (4) washing and drying intermediate product B, and mixing it with the coating material and sintering. The ternary cathode material of this invention has good power performance, long-term cycle performance, high-temperature cycle performance, and processing performance. The preparation method of this invention is simple and mild, improves the protective effect of the coating layer, reduces impedance, and improves the power and cycle performance of the material.

[0004] Existing technology CN 116072876 A discloses a high-nickel ternary cathode material and a method for removing residual alkali from its surface, relating it to lithium-ion batteries, belonging to the field of lithium-ion battery technology. The method includes: mixing a primary sintering material consisting of a precursor and a lithium source with an organic solvent, performing solid-liquid separation, and drying the solid phase; mixing the dried material with a coating material, and performing a secondary sintering; the organic solvent includes methanol; the coating material is C... O (OH)₂; secondary sintering is carried out at 300-800℃ for 8-12 hours. This method selectively removes LiOH and C from the material surface using organic solvents. O (OH)2 can remove Li2C from the surface of materials. O3 C O (OH)₂ reacts with Li₂CO₃ to generate LiC on the material surface. OAn O2 coating layer enhances the electrochemical performance of the material. The resulting high-nickel ternary cathode material has a low residual alkali content, and the resulting lithium-ion battery exhibits excellent electrochemical performance.

[0005] The invention patent with publication number CN103794773B discloses a method for large-scale production of 523 type ternary cathode material. It adopts a three-stage sintering process, which includes a tunnel kiln for low-temperature sintering, a roller kiln for secondary sintering with a full reaction stage, and a roller kiln for high-temperature holding treatment. This process makes the crystal structure of the product more complete and stable, and the crystal structure transitions smoothly, achieving a standardized overall structure of nickel, cobalt and manganese, thereby improving its comprehensive performance.

[0006] The invention patent CN115626668B discloses a method for preparing ternary cathodes in the laboratory. A mixed solution containing nickel salt, cobalt salt, and manganese salt is spray-dried and granulated. The resulting granules are sintered once to obtain a nickel-cobalt-manganese oxide precursor. The nickel-cobalt-manganese oxide precursor, lithium source, and flux (amide compounds, chlorides, metasilicates, etc.) are mixed and then sintered a second time to obtain an octahedral nickel-cobalt-manganese ternary cathode material. Its (100) and (010) crystal planes grow preferentially, which can increase the diffusion path of lithium ions, provide lithium ion transport power, and effectively improve lithium ion transport. When used in lithium-ion batteries, it maintains excellent reversible specific capacity while maintaining good rate performance and cycle performance under high voltage charge and discharge conditions.

[0007] The ternary cathode material preparation method mentioned in the above patent has problems such as low production efficiency, high production cost, poor product consistency, low capacity, and is not conducive to large-scale production. Utility Model Content

[0008] The purpose of this invention is to provide a system for the continuous production of ternary cathode materials, resulting in products with good consistency.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A system for producing ternary cathode materials includes a feeding device, a primary sintering device, a crushing device, a primary iron removal device, a primary auxiliary material adding device, a water washing device, a solid-liquid separation device, a drying device, a secondary auxiliary material adding device, a secondary sintering device, and a secondary iron removal device, connected in sequence.

[0011] After the NCM precursor and lithium source are mixed, they are sintered in a primary sintering equipment. After sintering, the material is first crushed in a crushing equipment. The crushed material is then conveyed to an iron removal equipment for iron removal. Auxiliary materials are added to the iron-removed material through a primary auxiliary material addition device and then sent to a water washing equipment for water washing. The water-washed material is then sent to a solid-liquid separation equipment. The filtrate is sent to wastewater treatment, and the filter residue is dried in a drying equipment. Auxiliary materials are added to the dried material through a secondary auxiliary material addition device and then sent to a secondary sintering equipment for secondary sintering. After sintering, the material is subjected to secondary iron removal in a secondary iron removal equipment for secondary iron removal. The material after secondary iron removal is then packaged to obtain the packaged ternary cathode material.

[0012] In one preferred embodiment, the feeding device includes a precursor temporary storage bin, a precursor metering bin, a precursor unpacking machine, a lithium source temporary storage bin, a lithium source metering bin, and a lithium source unpacking machine; the precursor unpacking machine, the precursor temporary storage bin, and the precursor metering bin are connected in sequence, and the lithium source unpacking machine, the lithium source temporary storage bin, and the lithium source metering bin are also connected in sequence.

[0013] In one preferred embodiment, a primary mixing device is also provided between the feeding device and the primary sintering device.

[0014] In one preferred embodiment, the primary mixing equipment includes a primary plow mixer and a primary ribbon mixer connected together; the primary plow mixer is connected to a feeding device, and the primary ribbon mixer is connected to a primary sintering device.

[0015] In one preferred embodiment, the primary plow mixer is connected to the precursor metering chamber and the lithium source metering chamber.

[0016] In one preferred embodiment, the primary sintering equipment includes a primary roller kiln and a gas tank connected thereto, and the primary roller kiln is connected to a crushing device.

[0017] In one preferred embodiment, the crushing equipment includes a coarse crushing device, a crushed material storage bin, a primary conveying device, a primary receiving bin, and a fine crushing device connected in sequence; the coarse crushing device is connected to the primary sintering device; and the fine crushing device is connected to the primary iron removal device.

[0018] In one preferred embodiment, the coarse crushing equipment is connected to the primary roller kiln;

[0019] In one preferred embodiment, the coarse crushing device is a primary double-layer roll crusher, the primary conveying device is a positive pressure conveying tank, and the fine crushing device is an air jet mill.

[0020] In one preferred embodiment, the primary iron removal device is an electromagnetic iron separator.

[0021] In one preferred embodiment, a secondary conveying device is provided between the primary iron removal device and the primary auxiliary material addition device, wherein the secondary conveying device is a positive pressure conveying tank.

[0022] In one preferred embodiment, the primary auxiliary material adding device includes an iron removal material receiving bin, a metering bin, and a primary auxiliary material unpacking machine; the metering bin is connected to both the iron removal material receiving bin and the primary auxiliary material unpacking machine; and the iron removal material receiving bin is connected to a secondary conveying device.

[0023] In one preferred embodiment, the washing equipment is a washing tank.

[0024] In one preferred embodiment, the solid-liquid separation device is a vertical filter press.

[0025] In one preferred embodiment, the drying equipment is a vacuum dryer.

[0026] In one preferred embodiment, the secondary auxiliary material adding device includes a dry material receiving bin, a secondary auxiliary material metering bin, and a secondary auxiliary material unpacking machine; the inlet of the dry material receiving bin is connected to the drying equipment and the secondary auxiliary material unpacking machine respectively; the outlet of the dry material receiving bin is connected to the secondary auxiliary material metering bin; and the secondary auxiliary material metering bin is connected to the secondary mixing equipment.

[0027] In one preferred embodiment, a secondary ribbon mixer and a tertiary conveying device are connected between the drying equipment and the secondary auxiliary material adding device; the secondary ribbon mixer is connected to the drying equipment, and the tertiary conveying device is connected to the dry material receiving bin.

[0028] In one preferred embodiment, the three-stage conveying device is a positive pressure conveying tank.

[0029] In one preferred embodiment, the secondary sintering equipment includes a secondary roller kiln and a gas tank connected thereto. The secondary roller kiln is connected to a secondary auxiliary material adding device and a secondary iron removal device.

[0030] In one preferred embodiment, the secondary auxiliary material adding device and the secondary sintering equipment are equipped with a secondary mixing device, which is connected to the secondary auxiliary material metering silo.

[0031] Multiple mixing devices are added during the process to mix different batches of materials evenly, resulting in products with small batch-to-batch variations.

[0032] In one preferred embodiment, the secondary mixing device is a secondary plow mixer.

[0033] In one preferred embodiment, a secondary crushing device, a secondary sintering material storage bin, a fourth conveying device, a secondary sintering material receiving bin, a tertiary mixing device, and a tertiary mixing material storage bin are sequentially connected between the secondary sintering device and the secondary iron removal device; the secondary crushing device and the secondary sintering device are connected, and the tertiary mixing material storage bin and the secondary iron removal device are connected.

[0034] In one preferred embodiment, the secondary crushing equipment is a secondary double roll crusher.

[0035] In one preferred embodiment, the fourth delivery device is a positive pressure delivery tank.

[0036] In one preferred embodiment, the secondary iron removal device is an iron separator.

[0037] In one preferred embodiment, the tertiary mixing device is a secondary ribbon mixer.

[0038] In one preferred embodiment, the outlet of the secondary iron removal equipment is connected to the secondary iron removal material temporary storage bin.

[0039] The NCM precursor and lithium source are each unpacked by an unpacking machine and temporarily stored in a temporary storage bin. They are then metered in a metering bin, and the precisely metered NCM precursor and lithium source are transported to a primary plow mixer for mixing. After mixing, they are fed into a primary ribbon mixer for thorough mixing. The fully mixed material is then fed into a primary roller kiln via an external circulation line for sintering. After sintering, the material is cooled inside the furnace and then discharged. The discharged material first undergoes coarse crushing in a primary double-layer roller crusher. The coarsely crushed material is then transported to a primary receiving bin via a positive pressure conveying tank, and further crushed by an air jet mill. The further crushed material is then subjected to iron removal by an electromagnetic separator and enters the iron-removed material receiving bin via a positive pressure conveying tank. Subsequently, the material and auxiliary materials delivered by a primary auxiliary material unpacking machine are mixed and precisely metered in a metering bin. The material and auxiliary materials are then fed into a washing tank for washing. After washing, the material is pumped to a vertical filter press. The filtrate is sent to a wastewater treatment plant, and the filter residue is dried by a vacuum dryer. After drying, the material enters a secondary ribbon mixer for cooling and homogenization. The cooled material is then sent to the dried material receiving silo via a positive pressure conveying tank. In the receiving silo, auxiliary materials from a secondary auxiliary material unpacking machine are mixed and transported to a secondary auxiliary material metering silo for precise metering. The material then enters a secondary plow mixer for further mixing. The homogenized material enters a secondary roller kiln for secondary sintering. After sintering, the material is crushed by a secondary double-roll crusher and enters a secondary sintering material storage silo. It is then sent to the secondary sintering material receiving silo via a positive pressure conveying tank and further conveyed to a secondary ribbon mixer for mixing. The mixed material is then transferred to a tertiary mixing material storage silo and subsequently enters an iron remover for iron removal. The iron-removed material enters a secondary iron-removed material storage silo and is transported to a packaging machine for packaging, yielding packaged ternary cathode materials.

[0040] The beneficial effects of this utility model are as follows:

[0041] This invention employs a segmented calcination process. In the first stage, the NCM precursor and lithium hydroxide are uniformly mixed and calcined at high temperature for a long period in a saturated oxygen environment to form a preliminary ternary cathode material with a stable crystal lattice. Then, the material is pulverized to the micron level, and alumina is added for deionized water washing to remove impurities and reduce the alkalinity of the material surface. The added slurry is then dried and mixed before a second sintering to form a modified high-capacity ternary cathode material with an outer alumina coating and a stable internal crystal lattice structure. The addition of alumina before water washing and the mixing and drying process thoroughly solve the problem of poor adhesion of the alumina coating film. This system has a high degree of automation and production efficiency, low production cost, and good product consistency. The modified ternary cathode material can effectively improve electrolyte decomposition, increase battery efficiency, and extend battery life. Attached Figure Description

[0042] Figure 1 This is a diagram showing the device connections of the system according to this utility model;

[0043] Figure 2 The process flow for producing cathode materials using NCM precursors;

[0044] In the diagram, 1-Precursor unpacking machine; 2-Precursor temporary storage bin; 3-Precursor metering bin; 4-Lithium source unpacking machine; 5-Lithium source temporary storage bin; 6-Lithium source metering bin; 7-Primary plow mixer; 8-Primary ribbon mixer; 9-Primary roller kiln; 10-Gas tank; 11-Primary double-layer roller crusher; 12-Crushed material temporary storage bin; 13-Positive pressure sending tank; 14-Primary receiving bin; 15-Air jet mill; 16-Electromagnetic separator; 17-Positive pressure sending tank; 18-Iron-removed material receiving bin; 19-Primary auxiliary material unpacking machine; 20-Metering bin; 2 1-Washing kettle; 22-Vertical filter press; 23-Vacuum dryer; 24-Secondary ribbon mixer; 25-Positive pressure sending tank; 26-Dried material receiving bin; 27-Secondary auxiliary material metering bin; 28-Secondary auxiliary material unpacking machine; 29-Secondary plow mixer; 30-Secondary roller kiln; 31-Secondary double roller crusher; 32-Secondary sintering material temporary storage bin; 33-Positive pressure sending tank; 34-Secondary sintering material receiving bin; 35-Secondary ribbon mixer; 36-Tertiary mixing material temporary storage bin; 37-Iron separator; 38-Secondary iron removal material temporary storage bin. Detailed Implementation

[0045] This utility model is not limited to the following specific embodiments. Those skilled in the art can implement this utility model using various other specific embodiments based on the disclosed content. Any modifications or alterations to the design structure and concept of this utility model fall within its protection scope. It should be noted that, unless otherwise specified, the embodiments and features described in this utility model can be combined with each other.

[0046] like Figure 1 As shown, a system for producing ternary cathode materials includes, in sequence, a feeding device, a primary mixing device, a primary sintering device, a crushing device, a primary iron removal device, a secondary conveying device, a primary auxiliary material adding device, a washing device, a solid-liquid separation device, a drying device, a secondary auxiliary material adding device, a secondary mixing device, a secondary sintering device, a secondary crushing device, a secondary sintering material temporary storage bin 32, a fourth conveying device, a secondary sintering material receiving bin 34, a tertiary mixing device, a tertiary mixing material temporary storage bin 36, and a secondary iron removal device;

[0047] The feeding equipment includes a precursor temporary storage chamber 2, a precursor metering chamber 3, a precursor unpacking machine 2, a lithium source temporary storage chamber 5, a lithium source metering chamber 6, and a lithium source unpacking machine 4; the precursor unpacking machine 1, the precursor temporary storage chamber 2, and the precursor metering chamber 3 are connected in sequence, and the lithium source unpacking machine 4, the lithium source temporary storage chamber 5, and the lithium source metering chamber 6 are connected in sequence.

[0048] The primary mixing equipment includes a primary plow mixer 7 and a primary ribbon mixer 8 connected together; the primary plow mixer 7 is connected to the precursor metering chamber 3 and the lithium source metering chamber 6 respectively, and the primary ribbon mixer 8 is connected to the primary sintering equipment.

[0049] The process involves two mixing stages. The first stage uses a single-stage plow mixer (7) for 1 hour per batch. The second stage uses a single-stage ribbon mixer (8). This enhances the mixing effect, resulting in finer materials, which improves sintering performance and increases product stability and consistency.

[0050] The primary sintering equipment includes a primary roller kiln 9 and a gas tank 10 connected thereto. The primary roller kiln 9 is also connected to a crushing device.

[0051] The crushing equipment includes a primary crusher, a crushed material storage bin 12, a primary conveyor, a primary receiving bin 14, and a fine crusher connected in sequence. The primary crusher is connected to the primary roller kiln 9; the fine crusher is connected to the primary iron removal equipment. The primary crusher is a primary double-layer roller crusher 11, the primary conveyor is a positive pressure conveying tank 13, and the fine crusher is an air jet mill 15. The primary iron removal equipment is an electromagnetic separator 16. The secondary conveyor is a positive pressure conveying tank 17.

[0052] First, a double-layer roller crusher 11 is used for coarse crushing, resulting in a material particle size of 1-2 mm. The material is then further crushed by an air jet mill 15, with the particle size controlled at 1-3 μm. The air jet mill has low power consumption, large capacity, low cost, and slow wear, producing finer powder particles. This increases the specific surface area of ​​the material, resulting in a larger contact area between the material and the electrolyte, shortening the lithium-ion diffusion path, and facilitating lithium-ion intercalation / deintercalation at high current densities, thus improving the material's rate performance.

[0053] The primary auxiliary material adding device includes an iron removal material receiving bin 18, a metering bin 20, and a primary auxiliary material unpacking machine 19; the metering bin 20 is connected to the iron removal material receiving bin 18 and the primary auxiliary material unpacking machine 19 respectively; the iron removal material receiving bin 18 is connected to the positive pressure sending tank 17.

[0054] The washing equipment is a washing tank 21. Pure water is used in the washing tank for alkali washing. Washing can effectively remove organic solvents, metal ions, dust and other impurities from the surface of ternary cathode materials, further improving the electrochemical performance and cycle stability of the materials, thereby enhancing the overall performance of lithium-ion batteries. It can also reduce the alkalinity of the material surface, which helps to inhibit the precipitation of lithium lattice on the material surface and reduce the amount of wastewater generated.

[0055] The solid-liquid separation equipment is a vertical filter press 22. The drying equipment is a vacuum dryer 23.

[0056] A secondary ribbon mixer 24 and a tertiary conveying device are connected between the vacuum dryer 23 and the dried material receiving bin 26; the secondary ribbon mixer 24 is connected to the vacuum dryer 23, and the tertiary conveying device is connected to the dried material receiving bin 26. The tertiary conveying device is a positive pressure conveying tank 25.

[0057] The secondary auxiliary material adding device includes a dry material receiving bin 26, a secondary auxiliary material metering bin 27, and a secondary auxiliary material unpacking machine 28; the inlet of the dry material receiving bin 26 is connected to the vacuum dryer 23 and the secondary auxiliary material unpacking machine 28 respectively; the outlet of the dry material receiving bin 26 is connected to the secondary auxiliary material metering bin 27; and the secondary auxiliary material metering bin 27 is connected to the secondary mixing equipment.

[0058] The secondary mixing equipment is a secondary plow mixer 29. The secondary plow mixer 29 is connected to the secondary auxiliary material metering hopper 27.

[0059] The secondary sintering equipment includes a secondary roller kiln 30 and a gas tank 10 connected thereto. The secondary roller kiln 30 is connected to a secondary plow mixer 29 and a secondary crushing device.

[0060] The secondary crushing equipment is a secondary double roll crusher 31. The fourth conveying equipment is a positive pressure conveying tank 33. The secondary iron removal equipment is an iron separator 37. The tertiary mixing equipment is a secondary ribbon mixer 35. The outlet of the secondary iron removal equipment is connected to the secondary iron removal material temporary storage silo 38.

[0061] Multiple mixing devices are added during the process to mix different batches of materials evenly, resulting in products with small batch-to-batch variations.

[0062] according to Figure 2 As shown, the NCM precursor and lithium source are unpacked by the unpacking machine and temporarily stored in the temporary storage bin. They are then metered in the metering bin, and the precisely metered NCM precursor and lithium source are transported to the primary plow mixer 7 for mixing. After mixing, the materials are discharged into the primary ribbon mixer 8 for thorough mixing. The thoroughly mixed material enters the primary roller kiln 9 through an external circulation line for sintering. The primary roller kiln 9 is supplied with 99.99% pure oxygen through the gas tank 10 to ensure an oxygen atmosphere inside the furnace. The sintered material is cooled inside the furnace and then discharged. The discharged material first enters the primary double-layer roller crusher 11 for coarse crushing. The coarsely crushed material enters the crushed material temporary storage bin 12, and then is conveyed to the primary receiving bin 14 through the positive pressure sending tank 13. It is then further crushed by the airflow pulverizer 15. The further crushed material passes through the electromagnetic separator 16 for iron removal and enters the iron-removed material receiving bin 18 through the positive pressure sending tank 17. Subsequently, the material and auxiliary materials delivered by the primary auxiliary material unpacking machine 19 are mixed and precisely metered in the metering silo 20. The material and auxiliary materials enter the washing tank 21 for washing. After washing, the material is pumped to the vertical filter press 22, the filtrate is sent to the wastewater treatment plant, and the filter residue is dried by the vacuum dryer 23. After drying, the material enters the secondary ribbon mixer 24 for cooling and uniform mixing. After cooling, the material is sent to the dry material receiving silo 26 via the positive pressure sending tank 25. In the dry material receiving silo 26, auxiliary materials delivered by the secondary auxiliary material unpacking machine 28 are mixed and transported to the secondary auxiliary material metering silo 27 for precise metering. Then, the material enters the secondary plow mixer 29 for mixing. The uniformly mixed material enters the secondary roller kiln 30 for secondary sintering. After sintering, the material is crushed by the secondary double-roll crusher 31 and enters the secondary sintering material storage bin 32. It is then sent to the secondary sintering material receiving bin 34 by the positive pressure sending tank 33 and continues to be conveyed to the secondary ribbon mixer 35 for mixing. The mixed material is then conveyed to the tertiary mixing material storage bin 36 and then enters the iron remover 37 for iron removal. The iron-removed material enters the secondary iron-removed material storage bin 38 and is transported to the packaging machine for packaging to obtain packaged ternary cathode materials.

[0063] The NCM precursor is nickel cobalt manganese hydroxide (Ni). 0.8 Co 0.1 Mn 0.1(OH)2; the lithium source is lithium hydroxide monohydrate; the molar ratio is 1:1.05. All unpacking machines are automatic. Reducing manual intervention, improving process automation and production efficiency, is beneficial to improving product consistency. The auxiliary material added twice is alumina; alumina is easy to prepare, has low production cost, and good chemical and thermal stability. As a coating material, it is beneficial to improve the stability, high-temperature resistance, and cycle performance of the cathode material, and extend battery life.

[0064] Lithium hydroxide is simple and low in cost to prepare; it is a high-purity lithium salt with good chemical stability, providing a high-quality lithium source that helps improve the performance and consistency of cathode materials; and it is an environmentally friendly lithium source that does not pollute the environment, contributing to green manufacturing.

[0065] The sintering process utilizes a roller kiln system at a temperature of 700-800℃ for 30 hours. During sintering, 99.99% pure oxygen is introduced to maintain an oxygen atmosphere within the furnace. Roller kilns offer a stable temperature field, low energy consumption, and support large-scale continuous production. Using roller kilns improves production efficiency, reduces costs, and enhances product consistency. Appropriately increasing the sintering temperature and extending the sintering time contributes to a more complete and stable crystal structure, ensuring a smooth transition and reducing free lithium on the material surface. An oxygen atmosphere facilitates the sintering process, ensuring uniform heating of the material and improving product consistency. Furthermore, an oxygen atmosphere reduces cation mixing, resulting in better rate performance. During sintering, the roller kiln system distributes the material as bottom and edge layers, ensuring uniform heating and improving product performance stability and consistency.

[0066] The secondary sintering also uses a roller kiln system, with a sintering temperature of 600-700℃ and a sintering time of 12-15 hours. During the sintering process, oxygen with a purity of 99.99% is introduced to ensure an oxygen atmosphere inside the furnace.

[0067] Multiple batches of materials in the finished product post-processing stage are added together to the secondary ribbon mixer 35 for batch mixing. After sufficient mixing, the materials are removed by the iron remover 37, which helps to improve the stability and consistency of product performance.

[0068] The metering chambers used in the system employ automatic weighing with an accuracy of one-thousandth. This effectively improves process automation and weighing accuracy, increases production efficiency, and ensures product performance stability and consistency.

[0069] The cathode material produced using the above process has a 1C discharge specific capacity of 190-201 mAh / g.

[0070] The performance of ternary cathode materials prepared using conventional processes and equipment is significantly inferior to that of this invention. The conventional processes are as follows:

[0071] Raw material mixing: using nickel cobalt manganese hydroxide (Ni) 0.5 Co 0.2 Mn 0.3 75 kg of (OH)2 ternary precursor was prepared with lithium carbonate and nickel, cobalt and manganese in a molar ratio of 1.04:1. The mixture was then dry-mixed using a high-speed mixer to achieve molecular-level mixing of lithium, nickel, cobalt and manganese and additive elements.

[0072] Three-stage sintering: The uniformly mixed raw materials are sintered once in a tunnel kiln at 650℃ for 5 hours. The ternary semi-finished product from the first sintering is then crushed and fed into a roller kiln for a second sintering at 815℃ for 10 hours. The ternary product from the second sintering is then crushed and fed into a roller kiln for a third sintering at 915℃ for 10 hours. During each of the above sintering processes, oxygen must be continuously supplied and carbon dioxide must be released in a timely manner to ensure a complete chemical reaction.

[0073] Post-sintering processing: After sintering, the ternary products are collected in time and crushed and pulverized in a dehumidified room with a humidity of less than 40%. The particle size of the product is controlled to D50 = 9-13um. After pulverization, the ternary products are mixed, sieved, iron removed, heat-sealed and packaged before being put into storage.

[0074] The high-capacity lithium manganese oxide produced by this process has a capacity of 173 mAh / g at 0.2C.

[0075] It should be noted that the above embodiments are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make other variations or modifications based on the above description. It is impossible to exhaustively list all possible implementations here. All obvious variations or modifications derived from the technical solution of the present utility model are still within the protection scope of the present utility model.

Claims

1. A system for producing ternary cathode materials, characterized in that, It includes a feeding device, a primary sintering device, a crushing device, a primary iron removal device, a primary auxiliary material adding device, a water washing device, a solid-liquid separation device, a drying device, a secondary auxiliary material adding device, a secondary sintering device, and a secondary iron removal device, all connected in sequence.

2. The system according to claim 1, characterized in that, A primary mixing device is also provided between the feeding device and the primary sintering device; the primary mixing device includes a primary plow mixer and a primary ribbon mixer connected together; The primary plow mixer and feeding equipment are connected, and the primary ribbon mixer and primary sintering equipment are connected.

3. The system according to claim 1, characterized in that, The primary sintering equipment includes a primary roller kiln and a gas tank connected to it, and the primary roller kiln is connected to a crushing device.

4. The system according to claim 1, characterized in that, The crushing equipment includes a primary crushing device, a crushed material storage bin, a primary conveying device, a primary receiving bin, and a fine crushing device connected in sequence; the primary crushing device is connected to the primary sintering device; the fine crushing device is connected to the primary iron removal device; the primary crushing device is a primary double-layer roller crusher, the primary conveying device is a positive pressure conveying tank, the fine crushing device is an air jet mill, and the primary iron removal device is an electromagnetic separator.

5. The system according to claim 1, characterized in that, A secondary conveying device is provided between the primary iron removal equipment and the primary auxiliary material addition device, and the secondary conveying device is a positive pressure conveying tank.

6. The system according to claim 1, characterized in that, A secondary ribbon mixer and a tertiary conveying device are connected between the drying equipment and the secondary auxiliary material adding device; the secondary ribbon mixer is connected to the drying equipment, and the tertiary conveying device is connected to the secondary auxiliary material adding device; the tertiary conveying device is a positive pressure conveying tank.

7. The system according to claim 1, characterized in that, The secondary auxiliary material adding device and the secondary sintering equipment are equipped with a secondary mixing device; the secondary mixing device is a secondary plow mixer.

8. The system according to claim 1, characterized in that, The secondary sintering equipment and the secondary iron removal equipment are connected in sequence to a secondary crushing equipment, a secondary sintering material temporary storage bin, a fourth conveying equipment, a secondary sintering material receiving bin, a tertiary mixing equipment, and a tertiary mixing material temporary storage bin; the secondary crushing equipment and the secondary sintering equipment are connected, and the tertiary mixing material temporary storage bin and the secondary iron removal equipment are connected.

9. The system according to any one of claims 1-8, characterized in that, The outlet of the secondary iron removal equipment is connected to the temporary storage silo for secondary iron removal materials.

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