A device and method for online preparation of nickel-cobalt-manganese-oxide lithium positive electrode materials with different structures

Abstract

The present invention discloses a device for preparing a positive electrode material of nickel cobalt lithium manganese oxide with different structures online, including a reactor, a diluter, an ammonia nitrogen detection analyzer, a PLC controller, and an ammonia water metering component. The diluter is connected to the reactor through a pipeline to form a loop, the ammonia water metering component is connected to the reactor through a pipeline, the ammonia nitrogen analyzer is arranged on the liquid outlet pipeline of the diluter, the ammonia nitrogen analyzer is connected to the input end of the PLC controller, and the output end of the PLC controller is connected to the ammonia water metering tank; the present invention also discloses a method for preparing a positive electrode material of nickel cobalt lithium manganese oxide with different structures online. The present invention effectively realizes the function of online monitoring and adjusting the ammonia concentration in the reaction system by setting a diluter, an ammonia nitrogen detection analyzer, a PLC controller, and an ammonia water metering component connected to the reactor, so that the reaction system operates according to the set requirements, thereby achieving the purpose of preparing a positive electrode material of nickel cobalt lithium manganese oxide with different structures.

Description

Technical Field

[0001] The invention belongs to the technical field of lithium ion battery positive electrode material preparation, and specifically relates to a device and method for online preparation of nickel cobalt manganese oxide lithium positive electrode materials with different structures. Background Art

[0002] The positive electrode material of power lithium-ion battery is one of the key materials for lithium-ion power batteries for new energy vehicles. Its market supply and demand are closely related to the market supply and demand of lithium-ion power batteries. The positive electrode material is a key material that plays a decisive role in the performance of lithium-ion batteries. It mainly includes lithium cobalt oxide (LiCoO2) and lithium nickel cobalt oxide (LiNi x Co 1-x O2), lithium nickel cobalt manganese oxide (LiNi x Co y Mn 1-x-y O2), lithium manganese oxide (LiMn2O4) and lithium iron phosphate (LiFePO4). The performance of the positive electrode material is determined by its corresponding precursor.

[0003] There are two main methods for preparing NCM622 materials with different structures. One is to control the pH value and ammonia concentration to synthesize Ni with different structural characteristics. 0.6 Co 0.2 Mn 0.2 (OH)2 precursor material, the NCM622 material prepared by the precursor inherits the structural characteristics of the precursor very well; the study shows that this method can well control the arrangement of the primary particles of the material and the growth direction of the crystal, so that the (100) and (010) crystal planes face the surface of the electrode particles, thereby improving the structural stability and rate performance of the material in the long-term cycle process; the other is to use Ni, Co, Mn sulfate as raw materials, NaOH as precipitant, ammonia water as complexing agent, and control the pH of the reaction system at 11.5, 11.0, and 10.5 respectively by controlling the concentration of ammonia water, thereby obtaining spherical Ni with different structural characteristics 0.6 Co 0.2 Mn 0.2 The (OH)2 precursor material is dried and mixed with Li2CO3, and then calcined to obtain NCM622 material with different structural characteristics; it can be seen from these two methods that the ammonia concentration in the reaction system needs to be controlled. Since the current detection of ammonia concentration is mostly manual, it is difficult to ensure the stability of ammonia concentration. Therefore, how to timely detect and adjust the ammonia concentration in the reaction system becomes a key factor. Summary of the invention

[0004] In view of this, the main purpose of the present invention is to provide an apparatus for online preparation of nickel cobalt manganese oxide positive electrode materials with different structures, which solves the problem that the existing technology mainly relies on manual control of ammonia concentration, which makes it difficult to ensure the stability of ammonia concentration and affects the reaction results.

[0005] To achieve the above-mentioned purpose, the technical solution of the present invention is implemented as follows: a device for online preparation of nickel cobalt manganese oxide lithium positive electrode materials with different structures, comprising a reactor, a diluter, an ammonia nitrogen analyzer, a PLC controller, and an ammonia water metering component, wherein the diluter is connected to the reactor through a pipeline to form a loop, the ammonia water metering component is connected to the reactor through a pipeline, the ammonia nitrogen analyzer is arranged on the liquid outlet pipeline of the diluter, the ammonia nitrogen analyzer is connected to the input end of the PLC controller, and the output end of the PLC controller is connected to the ammonia water metering tank.

[0006] Preferably, the diluent outlet is provided on the diluter, and the ammonia nitrogen analyzer is provided with an ammonia nitrogen analysis electrode probe, and the ammonia nitrogen analysis electrode probe is located in a pipeline connected to the diluent outlet.

[0007] Preferably, it also includes a filtering component, which is arranged on a pipeline connecting the reactor and the diluter and is connected to the reactor to form a loop.

[0008] Preferably, the ammonia metering component includes an ammonia storage tank, an ammonia metering pump, and an ammonia meter. The ammonia storage tank, the ammonia metering pump, the ammonia meter, and the reactor are connected in sequence through pipelines, and the output end of the PLC controller is connected to the liquid outlet valve of the ammonia metering pump.

[0009] Preferably, the filter assembly comprises a filter tank and a filtrate tank connected to the filter tank, the filtrate tank is connected to a diluter, and the filter tank is connected to a reactor through a pipeline to form a loop.

[0010] Preferably, a sampling pump is also provided on the pipeline connecting the filter assembly and the reactor.

[0011] Preferably, regulating valves are provided on the pipeline connecting the reactor and the sampling pump, on the pipeline connecting the filter assembly and the diluter, and on the liquid outlet pipeline of the diluter.

[0012] Preferably, a raw material inlet and a precipitant inlet are provided on the upper side wall of the reactor.

[0013] Another technical solution of the present invention is achieved as follows: a method for online preparation of nickel cobalt manganese oxide positive electrode materials with different structures, the method is achieved by the following steps:

[0014] Step 1, preparing a mixed solution of nickel, cobalt and manganese salts in a molar ratio of (8-1): (2-1): (3-1) of nickel, cobalt and manganese, and setting it aside; preparing a sodium hydroxide solution, and setting it aside; preparing an ammonia complexing agent solution and placing it in an ammonia metering component;

[0015] Step 2, adding the mixed solution of nickel-cobalt-manganese salt, sodium hydroxide solution and ammonia complexing agent solution in the ammonia metering component described in step 1 into the reactor at the same time, keeping the flow rate of the mixed solution of nickel-cobalt-manganese salt and the sodium hydroxide solution the same and unchanged during the feeding process, adjusting the flow rate of ammonia water online and controlling the pH of the reaction system to be 11-12, 10.5-11.5, and 10-11 respectively through the coordination between the ammonia nitrogen detection analyzer, the PLC controller and the ammonia metering component, and reacting for 10-80 hours at intervals to obtain nickel-cobalt-manganese oxide lithium precursors with different structures;

[0016] Step 3, drying the lithium nickel cobalt manganese oxide precursor obtained in step 2, mixing it with Li2CO3, and then calcining it to obtain a lithium nickel cobalt manganese oxide positive electrode material with different structures.

[0017] In the step 1, the total concentration of nickel, cobalt and manganese in the mixed solution of nickel, cobalt and manganese salts is 1.2-2.5 mol / L; the concentration of the sodium hydroxide solution is 6-12 mol / L; and the concentration of the ammonia solution is 8-12 mol / L.

[0018] Compared with the prior art, the present invention effectively realizes online monitoring and adjustment of the ammonia concentration in the reaction system by setting a diluter, an ammonia nitrogen detection analyzer, a PLC controller, and an ammonia water metering component connected to the reactor, so that the reaction system operates according to the set requirements, thereby achieving the purpose of preparing nickel cobalt manganese oxide positive electrode materials with different structures. At the same time, it also avoids the problem of inaccurate and unstable concentration monitoring when manually monitoring the ammonia concentration, which leads to a decrease in the performance of the prepared positive electrode material. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of the structure of an apparatus for online preparation of nickel cobalt manganese oxide positive electrode materials with different structures provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] The embodiment of the present invention provides an apparatus for online preparation of nickel cobalt manganese oxide positive electrode materials with different structures, such as Figure 1As shown, it includes a reactor 1, a diluter 2, an ammonia nitrogen detection analyzer 3, a PLC controller 4, and an ammonia water metering component 5. The diluter 2 is connected to the reactor 1 through a pipeline to form a loop. The ammonia water metering component 5 is connected to the reactor 1 through a pipeline. The ammonia nitrogen analyzer 3 is arranged on the liquid outlet pipeline of the diluter 2. The ammonia nitrogen analyzer 3 is connected to the input end of the PLC controller 4, and the output end of the PLC controller 4 is connected to the ammonia water metering tank 5. In the device, by arranging the diluter 2, the ammonia nitrogen detection analyzer 3, the PLC controller 4, and the ammonia water metering component 5 connected to the reactor 1, the online monitoring and adjustment of the ammonia concentration in the reaction system are effectively realized, so that the reaction system operates according to the set requirements, thereby achieving the purpose of preparing nickel cobalt manganese oxide lithium positive electrode materials with different structures (different crystal forms), and also avoiding the inaccurate and unstable concentration monitoring when manually monitoring the ammonia concentration, resulting in the degradation of the performance of the prepared positive electrode material.

[0022] Furthermore, the diluter 2 is provided with a dilution liquid outlet 21, and the ammonia nitrogen analyzer 3 is provided with an ammonia nitrogen analysis electrode probe 31, and the ammonia nitrogen analysis electrode probe 31 is located in a pipe connected to the dilution liquid outlet 21; by setting the ammonia nitrogen analysis electrode probe 31 in the pipe connected to the dilution liquid outlet 21, the ammonia concentration in the reaction system can be detected at all times, and the accuracy of detecting the ammonia concentration is improved.

[0023] Furthermore, it also includes a filter component 6, which is arranged on the pipeline connecting the reactor 1 and the diluter 2 and is connected to the reactor 1 to form a loop; by arranging the filter component 6 on the pipeline connecting the reactor 1 and the diluter 2, the problem of the liquid entering the diluter 2 containing solid matter (nickel hydroxide precipitate, manganese hydroxide precipitate, cobalt hydroxide precipitate, etc. generated in the reaction system) affecting the detection effect of ammonia concentration is effectively avoided; by connecting the filter component 6 to the reactor 1 and forming a loop, it is convenient to return the filtered solid matter to the reactor 1, which effectively avoids the waste of reactants and also ensures the stability of the ratio between the materials in the reaction system, creating favorable conditions for the preparation of nickel cobalt manganese oxide lithium positive electrode materials with excellent performance and different structures.

[0024] Furthermore, the ammonia metering component 5 includes an ammonia storage tank 51, an ammonia metering pump 52, and an ammonia meter 53. The ammonia storage tank 51, the ammonia metering pump 52, the ammonia meter 53, and the reactor 1 are connected in sequence through pipelines, and the output end of the PLC controller 4 is connected to the liquid outlet valve of the ammonia metering pump 52; by setting the ammonia metering pump 52 and the ammonia meter 53, the flow rate of ammonia flowing into the reactor 1 is controlled by the PLC controller 4, and the total amount of ammonia flowing into the reactor 1 is counted, which is beneficial to the statistics of the entire reaction data and the evaluation of the reaction results after the reaction is completed.

[0025] Furthermore, the filter assembly 6 includes a filter tank 61 and a filtrate tank 62 connected to the filter tank 61 . The filtrate tank 62 is connected to the diluter 2 . The filter tank 61 is connected to the reactor 1 through a pipeline to form a loop.

[0026] Furthermore, a sampling pump 7 is provided on the pipeline connecting the filter assembly 6 and the reactor 1 .

[0027] Furthermore, regulating valves 8 are provided on the pipeline connecting the reactor 1 and the sampling pump 7 , on the pipeline connecting the filter assembly 6 and the diluter 2 , and on the liquid outlet pipeline of the diluter 2 .

[0028] Furthermore, a raw material inlet 11 and a precipitant inlet 12 are provided on the upper side wall of the reactor 1 .

[0029] The use principle of an apparatus for online preparation of nickel cobalt manganese oxide positive electrode materials with different structures provided by an embodiment of the present invention is as follows:

[0030] An ammonia nitrogen analyzer 3 is used to monitor the ammonia concentration in the reaction system online, and the data is fed back to the PLC controller 4. The PLC controller 4 adjusts the feed flow of the ammonia water metering pump 52 according to the feedback data, realizing online monitoring and online adjustment, so that the reaction system operates according to the set requirements.

[0031] The embodiment of the present invention also provides a method for online preparation of nickel cobalt manganese oxide positive electrode materials with different structures, which is achieved by the following steps:

[0032] Step 1, preparing a mixed solution of nickel cobalt manganese salts with a total concentration of 1.2-2.5 mol / L according to the molar ratio of nickel, cobalt and manganese of (8-1):(2-1):(3-1), and setting aside; preparing a sodium hydroxide solution with a concentration of 6-12 mol / L, and setting aside; preparing an ammonia complexing agent solution with a concentration of 8-12 mol / L and placing it in an ammonia metering component 5;

[0033] Step 2, adding the mixed solution of nickel-cobalt-manganese salts, the sodium hydroxide solution and the ammonia complexing agent solution in the ammonia metering component (5) described in step 1 into the reactor (1) at the same time, keeping the flow rates of the mixed solution of nickel-cobalt-manganese salts and the sodium hydroxide solution the same and unchanged during the feeding process, adjusting the flow rate of ammonia water online and controlling the pH of the reaction system to be respectively 11 to 12, 10.5 to 11.5, and 10 to 11 through the coordinated action of the ammonia nitrogen detection analyzer (3), the PLC controller (4) and the ammonia metering component (5), and performing the reaction at intervals of 10 to 80 hours to obtain nickel-cobalt-manganese lithium oxide precursors with different structures;

[0034] Step 3, drying the lithium nickel cobalt manganese oxide precursor obtained in step 2, mixing it with Li2CO3, and then calcining it to obtain a lithium nickel cobalt manganese oxide positive electrode material with different structures.

[0035] Example 1

[0036] Step 1, prepare a mixed solution of nickel cobalt manganese salts with a total concentration of 3 mol / L of nickel, cobalt and manganese in a molar ratio of 1:1:1, and set aside; prepare a sodium hydroxide solution with a concentration of 9 mol / L, and set aside; prepare an ammonia complexing agent solution with a concentration of 10 mol / L and place it in the ammonia metering component 5;

[0037] Step 2, adding the mixed solution of nickel-cobalt-manganese salt, sodium hydroxide solution and ammonia complexing agent solution in ammonia metering component 5 described in step 1 into reactor 1 at the same time, keeping the flow rate of the mixed solution of nickel-cobalt-manganese salt and sodium hydroxide solution the same and unchanged during the feeding process, adjusting the flow rate of ammonia water online and controlling the pH of the reaction system to 11.5, 11, and 10.5 respectively through the cooperation between the ammonia nitrogen detection analyzer 3, the PLC controller 4 and the ammonia metering component 5, and reacting for 3 hours at intervals to obtain nickel-cobalt-manganese oxide lithium precursors with different structures;

[0038] Step 3, drying the lithium nickel cobalt manganese oxide precursor obtained in step 2, mixing it with Li2CO3, and then calcining it to obtain a lithium nickel cobalt manganese oxide positive electrode material with different structures.

[0039] Example 2

[0040] Step 1, preparing a mixed solution of nickel cobalt manganese salts with a total concentration of 2 mol / L of nickel, cobalt and manganese in a molar ratio of 8:1:1, and setting aside; preparing a sodium hydroxide solution with a concentration of 6 mol / L, and setting aside; preparing an ammonia complexing agent solution with a concentration of 8 mol / L and placing it in an ammonia metering component 5;

[0041] Step 2, adding the mixed solution of nickel-cobalt-manganese salt, sodium hydroxide solution and ammonia complexing agent solution in ammonia metering component 5 described in step 1 into reactor 1 at the same time, keeping the flow rate of the mixed solution of nickel-cobalt-manganese salt and sodium hydroxide solution the same and unchanged during the feeding process, adjusting the flow rate of ammonia water online through the cooperation between ammonia nitrogen detection analyzer 3, PLC controller 4 and ammonia metering component 5 and controlling the pH of the reaction system to be a point value between 11.5, 11 and 10.5 respectively, and reacting for 2 hours at intervals, to obtain nickel-cobalt-manganese oxide lithium precursors with different structures;

[0042] Step 3, drying the lithium nickel cobalt manganese oxide precursor obtained in step 2, mixing it with Li2CO3, and then calcining it to obtain a lithium nickel cobalt manganese oxide positive electrode material with different structures.

[0043] Example 3

[0044] Step 1, prepare a mixed solution of nickel cobalt manganese salts with a total concentration of 4 mol / L of nickel, cobalt and manganese in a molar ratio of 6:2:2, and set aside; prepare a sodium hydroxide solution with a concentration of 12 mol / L, and set aside; prepare an ammonia complexing agent solution with a concentration of 12 mol / L and place it in an ammonia metering component 5;

[0045] Step 2, adding the mixed solution of nickel-cobalt-manganese salt, sodium hydroxide solution and ammonia complexing agent solution in ammonia metering component 5 described in step 1 into reactor 1 at the same time, keeping the flow rate of the mixed solution of nickel-cobalt-manganese salt and sodium hydroxide solution the same and unchanged during the feeding process, adjusting the flow rate of ammonia water online through the cooperation between ammonia nitrogen detection analyzer 3, PLC controller 4 and ammonia metering component 5 and controlling the pH of the reaction system to be a point value between 11.5, 11 and 10.5 respectively, and reacting for 4 hours at intervals to obtain nickel-cobalt-manganese oxide lithium precursors with different structures;

[0046] Step 3, drying the lithium nickel cobalt manganese oxide precursor obtained in step 2, mixing it with Li2CO3, and then calcining it to obtain a lithium nickel cobalt manganese oxide positive electrode material with different structures.

[0047] Example 4

[0048] Step 1, prepare a mixed solution of nickel cobalt manganese salt with a total concentration of 2 mol / L of nickel, cobalt and manganese in a molar ratio of 5:2:3, and set it aside; prepare a sodium hydroxide solution with a concentration of 6 mol / L, and set it aside; prepare an ammonia complexing agent solution with a concentration of 8 mol / L and place it in the ammonia metering component 5;

[0049] Step 2, adding the mixed solution of nickel-cobalt-manganese salt, sodium hydroxide solution and ammonia complexing agent solution in ammonia metering component 5 described in step 1 into reactor 1 at the same time, keeping the flow rate of the mixed solution of nickel-cobalt-manganese salt and sodium hydroxide solution the same and unchanged during the feeding process, adjusting the flow rate of ammonia water online through the cooperation between ammonia nitrogen detection analyzer 3, PLC controller 4 and ammonia metering component 5 and controlling the pH of the reaction system to be a point value between 11, 10.5 and 10, respectively, and reacting for 2 hours at intervals, to obtain nickel-cobalt-manganese oxide lithium precursors with different structures;

[0050] Step 3, drying the lithium nickel cobalt manganese oxide precursor obtained in step 2, mixing it with Li2CO3, and then calcining it to obtain a lithium nickel cobalt manganese oxide positive electrode material with different structures.

[0051] Example 5

[0052] Step 1, preparing a mixed solution of nickel cobalt manganese salts with a total concentration of 4 mol / L of nickel, cobalt and manganese in a molar ratio of 1:1:1, and setting aside; preparing a sodium hydroxide solution with a concentration of 12 mol / L, and setting aside; preparing an ammonia complexing agent solution with a concentration of 12 mol / L and placing it in an ammonia metering component 5;

[0053] Step 2, adding the mixed solution of nickel-cobalt-manganese salt, sodium hydroxide solution and ammonia complexing agent solution in ammonia metering component 5 described in step 1 into reactor 1 at the same time, keeping the flow rate of the mixed solution of nickel-cobalt-manganese salt and sodium hydroxide solution the same and unchanged during the feeding process, adjusting the flow rate of ammonia water online and controlling the pH of the reaction system to a point value between 12, 11..5 and 11 respectively through the cooperation between the ammonia nitrogen detection analyzer 3, the PLC controller 4 and the ammonia metering component 5, and reacting for 4 hours at intervals to obtain nickel-cobalt-manganese oxide lithium precursors with different structures;

[0054] Step 3, drying the lithium nickel cobalt manganese oxide precursor obtained in step 2, mixing it with Li2CO3, and then calcining it to obtain a lithium nickel cobalt manganese oxide positive electrode material with different structures.

[0055] When the above-mentioned device is used to prepare positive electrode materials, compared with the prior art, the present invention effectively realizes online monitoring and adjustment of the ammonia concentration in the reaction system by setting a diluter, an ammonia nitrogen detection analyzer, a PLC controller, and an ammonia water metering component connected to the reactor, so that the reaction system operates according to the set requirements, thereby achieving the purpose of preparing nickel cobalt manganese oxide positive electrode materials with different structures. At the same time, it also avoids the inaccurate and unstable concentration monitoring when manually monitoring the ammonia concentration, which leads to a decrease in the performance of the prepared positive electrode material.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention.

Claims

1. A method for online preparation of nickel cobalt lithium manganese oxide positive electrode materials with different structures, characterized in that: in, It includes a reactor, a diluter, an ammonia nitrogen analyzer, a PLC controller, and an ammonia water metering component. The diluter is connected to the reactor through a pipeline to form a loop. The ammonia water metering component is connected to the reactor through a pipeline. The ammonia nitrogen analyzer is arranged on the liquid outlet pipeline of the diluter. The ammonia nitrogen analyzer is connected to the input end of the PLC controller, and the output end of the PLC controller is connected to the ammonia water metering tank; the diluter is provided with a diluent outlet, and the ammonia nitrogen analyzer is provided with an ammonia nitrogen analysis electrode probe, and the ammonia nitrogen analysis electrode probe is located in a pipeline connected to the diluent outlet; it also includes a filter component, which is arranged on the pipeline connecting the reactor and the diluter and connected to the reactor to form a loop; the ammonia water metering component includes an ammonia water storage tank, an ammonia water metering pump, and an ammonia water meter. The ammonia water storage tank, the ammonia water metering pump, the ammonia water meter, and the reactor are connected in sequence through pipelines, and the output end of the PLC controller is connected to the liquid outlet valve of the ammonia water metering pump; The method is implemented by the following steps: Step 1, preparing a mixed solution of nickel, cobalt and manganese salts in a molar ratio of (8-1): (2-1): (3-1) of nickel, cobalt and manganese, and setting it aside; preparing a sodium hydroxide solution, and setting it aside; preparing an ammonia complexing agent solution and placing it in an ammonia metering component; Step 2, adding the mixed solution of nickel-cobalt-manganese salts, the sodium hydroxide solution and the ammonia complexing agent solution in the ammonia metering component described in step 1 into the reactor (1) at the same time, keeping the flow rates of the mixed solution of nickel-cobalt-manganese salts and the sodium hydroxide solution the same and unchanged during the feeding process, adjusting the flow rate of ammonia water online and controlling the pH of the reaction system to be respectively 11-12, 10.5-11.5 and 10-11 through the coordination between the ammonia nitrogen detection analyzer, the PLC controller and the ammonia metering component, and performing the reaction at intervals of 10-80 hours to obtain nickel-cobalt-manganese oxide lithium precursors with different structures; Step 3, drying the lithium nickel cobalt manganese oxide precursor obtained in step 2, mixing it with Li2CO3, and then calcining it to obtain a lithium nickel cobalt manganese oxide positive electrode material with different structures.

2. The method for online preparation of nickel-cobalt-manganese-oxide lithium positive electrode materials with different structures according to claim 1, characterized in that: In the step 1, the total concentration of nickel, cobalt and manganese in the mixed solution of nickel, cobalt and manganese salts is 1.2-2.5 mol / L; the concentration of the sodium hydroxide solution is 6-12 mol / L; and the concentration of the ammonia solution is 8-12 mol / L.

3. The method for online preparation of nickel cobalt manganese oxide positive electrode materials with different structures according to claim 2, characterized in that: The filter assembly comprises a filter tank and a filtrate tank connected to the filter tank, the filtrate tank is connected to a diluter, and the filter tank is connected to a reactor through a pipeline to form a loop.

4. The method for online preparation of nickel cobalt manganese oxide positive electrode materials with different structures according to claim 3, characterized in that: A sampling pump is also provided on the pipeline connecting the filtering component and the reactor.

5. The method for online preparation of nickel-cobalt-manganese-oxide lithium positive electrode materials with different structures according to claim 4, characterized in that: Regulating valves are arranged on the pipeline connecting the reactor and the sampling pump, on the pipeline connecting the filter assembly and the diluter, and on the liquid outlet pipeline of the diluter.

6. A method for online preparation of nickel-cobalt-manganese-oxide lithium positive electrode materials with different structures according to any one of claims 1 to 5, characterized in that: The upper side wall of the reactor is provided with a raw material inlet and a precipitant inlet.

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