Positive electrode material precursor, positive electrode material and preparation method thereof

Abstract

The invention provides a ternary positive electrode material precursor, a ternary positive electrode material and a preparation method thereof. The preparation method of the ternary positive electrode material precursor comprises the following steps: (1) coprecipitation reaction: carrying out coprecipitation reaction by adopting a micro-channel reactor to obtain a reaction solution containing the ternary positive electrode material precursor; (2) aging: aging the reaction liquid obtained in the step (1), and before aging, adjusting the pH value of the reaction liquid to 9.5-12.5, or adding an auxiliary agent into the reaction liquid; and (3) post-treatment: carrying out post-treatment on the ternary positive electrode material precursor aged in the step (2), wherein the post-treatment comprises washing, dehydrating, drying and crushing. According to the method provided by the invention, the problems that the particle morphology is amorphous, the particle size is difficult to control and the tap density is low due to random agglomeration of primary particles of the positive electrode material precursor prepared by the microchannel reactor can be solved.

Description

Technical Field

[0001] The invention belongs to the technical field of battery materials and relates to a positive electrode material precursor, a positive electrode material and a preparation method thereof. Background Art

[0002] Using microchannel reactors to replace traditional kettle reactors to prepare ternary cathode material precursors is one of the research hotspots in cathode material preparation. The confinement effect and rapid mass and heat transfer efficiency of the microchannel reactor significantly increase the reaction rate. The extremely short reaction time organically separates the nucleation and growth processes of the grains, greatly improving production efficiency and reducing the footprint of production equipment. Due to the extremely fast microreaction rate, the rapid nucleation process leads to random distribution of secondary particle agglomerates, the particle size distribution is difficult to control, the morphology tends to be irregular, and the tap density is significantly reduced, resulting in a significant increase in the processing cost of the subsequent cathode sintering process.

[0003] In order to control the particle size and morphology of the cathode material precursor prepared by the microchannel reactor and improve the tap density and processing performance, the existing technology often slows down the crystal growth process by reducing the concentration of the reaction solution or reducing the feed flux, or reshapes the particle size and morphology by spray drying or re-granulation in the post-processing stage. The former method loses the efficiency of the precursor preparation, and the latter method adds steps, making the preparation process complicated.

[0004] Therefore, there is a need in the art for a method for preparing a cathode material precursor that uses a microchannel reactor and is capable of controlling particle morphology and particle size and improving tap density. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a positive electrode material precursor, a positive electrode material and a preparation method thereof. The present invention intervenes in the aging stage of the positive electrode material precursor, controls the agglomeration of primary particles during growth by adjusting the pH value of the reaction solution or adding an auxiliary agent, optimizes the particle size distribution of the product, and improves the tap density. The method provided by the present invention can solve the problem that the primary particles of the positive electrode material precursor prepared by the microchannel reactor randomly agglomerate, resulting in amorphous particle morphology, difficult to control particle size and low tap density.

[0006] Specifically, one aspect of the present invention provides a method for preparing a ternary cathode material precursor, the preparation method comprising the following steps:

[0007] (1) Co-precipitation reaction: a microchannel reactor is used to carry out a co-precipitation reaction to obtain a reaction solution containing a ternary cathode material precursor;

[0008] (2) Aging: Aging the reaction solution obtained in step (1). Before aging, the pH value of the reaction solution is adjusted to 9.5 to 12.5, or an auxiliary agent is added to the reaction solution.

[0009] (3) Post-treatment: The ternary cathode material precursor aged in step (2) is post-treated, and the post-treatment includes washing, dehydration, drying and crushing.

[0010] In one or more embodiments, in step (2), the holding temperature during the aging process is 25 to 80°C, preferably 30 to 65°C.

[0011] In one or more embodiments, in step (2), before aging, the pH value of the reaction solution is adjusted to 9.5 to 12.1.

[0012] In one or more embodiments, in step (2), the aging time is 2 to 12 hours.

[0013] In one or more embodiments, in step (2), nitrogen protection is performed during the aging process, and the nitrogen flow rate is preferably 5 to 10 L / min.

[0014] In one or more embodiments, in step (2), the reaction solution is stirred during the aging process, and the stirring speed is preferably 80 to 100 rpm.

[0015] In one or more embodiments, in step (2), the auxiliary agent is selected from one or more of a surfactant, an ammonium salt and a pH regulator, and the mass ratio of the reaction solution to the auxiliary agent is (10-200):1, preferably (40-60):1.

[0016] In one or more embodiments, the ammonium salt is selected from one or more of ammonium sulfate, ammonium bisulfate, ammonium carbonate, ammonium bicarbonate, and diammonium phosphate.

[0017] In one or more embodiments, the pH adjuster is selected from one or more of sodium bisulfate, sodium dihydrogen phosphate, and aluminum chloride.

[0018] In one or more embodiments, the auxiliary agent is selected from one or more of an ammonium salt and a pH adjuster.

[0019] In one or more embodiments, the adjuvant is ammonium sulfate and / or sodium bisulfate.

[0020] In one or more embodiments, the chemical formula of the ternary cathode material precursor is Ni x Co y M z (OH) 2 , wherein 0.6≤x≤0.95, 0<y≤0.2, 0<z≤0.3, x+y+z=1, and M is Al or Mn.

[0021] In one or more embodiments, in step (1), the ternary cathode material precursor is generated by co-precipitation reaction of nickel salt, cobalt salt and aluminum salt or nickel salt, cobalt salt and manganese salt in the presence of a precipitant and a complexing agent in a microchannel reactor.

[0022] In one or more embodiments, the microchannel reactor is a valve-type microreactor, which includes a first feed port, a second feed port, a first feed pressure regulating device, a second feed pressure regulating device, a reaction chamber and a discharge port, wherein the first feed port is connected to the reaction chamber through a first flow channel, the second feed port is connected to the reaction chamber through a second flow channel, the first feed pressure regulating device is arranged on the first flow channel between the first feed port and the reaction chamber, and is used to control the feed pressure of the first feed port, the second feed pressure regulating device is arranged on the second flow channel between the second feed port and the reaction chamber, and is used to control the feed pressure of the second feed port, the discharge port is connected to the reaction chamber, the nickel salt, cobalt salt and aluminum salt or nickel salt, cobalt salt and manganese salt are fed to the reaction chamber through the first flow channel, and the precipitant and complexing agent are fed to the reaction chamber through the second flow channel;

[0023] In one or more embodiments, the end of the first flow channel and the end of the second flow channel are provided with a plurality of micropores and / or slits distributed in an annular shape, so that the jets ejected from the end of the first flow channel and the end of the second flow channel correspond one to one, and real-time collision and mixing occur.

[0024] In one or more embodiments, step (3) comprises the following steps:

[0025] (3-1) Dehydration: removing the mother liquor from the aged material;

[0026] (3-2) washing: using water at 50-80° C., preferably 60-80° C., and placing the water and the material into a beating kettle in a water:material mass ratio of (5-15):1, preferably (6-12):1, for stirring and beating. The beating time is 30-120 min, preferably 45-90 min, and the stirring speed is 50-200 rpm, preferably 60-150 rpm;

[0027] (3-3) Dehydration: Dehydrating the material after pulping;

[0028] (3-4) repeating the washing step (3-2) and the dehydration step (3-3), with the total number of washings being ≥ 2 times, until the pH of the washing water is ≤ 9.5;

[0029] (3-5) Drying and crushing: Drying and crushing the washed and dehydrated material to obtain a ternary positive electrode material precursor.

[0030] Another aspect of the present invention provides a ternary cathode material precursor prepared by the preparation method described in any embodiment of the present invention.

[0031] In one or more embodiments, the Dmin of the ternary cathode material precursor is 0.8 to 1.6 μm.

[0032] In one or more embodiments, the D10 of the ternary cathode material precursor is 1.8 to 3.2 μm.

[0033] In one or more embodiments, the D50 of the ternary cathode material precursor is 5 to 19 μm.

[0034] In one or more embodiments, the D90 of the ternary cathode material precursor is 20 to 60 μm.

[0035] In one or more embodiments, the tap density of the ternary cathode material precursor is 1.3 to 1.8 g / mL.

[0036] Another aspect of the present invention provides a ternary positive electrode material prepared from the ternary positive electrode material precursor described in any embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 Schematic diagram of a valved microreactor in some embodiments of the present invention. Figure 1 In the figure, 201 is the first feed inlet, 202 is the second feed inlet, 203 is the second feed pressure regulating device, 204 is the first feed pressure regulating device, 205 is the reaction chamber, and 206 is the discharge port.

[0038] Figure 2 Schematic diagram of a system for preparing a cathode material precursor in some embodiments of the present invention. Figure 2 In the figure, 101 is a first feeding system, 102 is a second feeding system, 103 is a connecting pipeline, 104 is a valve type microreactor, 105 is a vacuum negative pressure tank, 106 is a vacuum pump, and 107 is an aging device.

[0039] Figure 3 Schematic diagram of a system for preparing a cathode material precursor in some embodiments of the present invention. Figure 3In the figure, 101 is the first feeding system, 102 is the second feeding system, 104 is the valve type microreactor, 105 is the vacuum negative pressure tank, 106 is the vacuum pump, 107 is the aging device, 108 is the first raw material tank, 109 is the first washing water tank, 301 is the first feeding device, 302 is the first mass flow meter, 303 is the first pressure controller, 304 is the first reversing valve, 110 is the second raw material tank, 111 is the second washing water tank, 401 is the second feeding device, 402 is the second mass flow meter, 403 is the second pressure controller, and 404 is the second reversing valve.

[0040] Figure 4 Schematic diagram of a system for preparing a cathode material precursor in some embodiments of the present invention. Figure 4 Among them, 108 is the first raw material tank, 110 is the second raw material tank, 112 is the third raw material tank, 101 is the first feeding system, 102 is the second feeding system, 103 is the third feeding system, 114 is the first inlet module, 115 is the first heating module, 116 is the second inlet module, 117 is the third inlet module, 119 is the mixing module, 120 is the second heating module, 104 is the valve microreactor, 121 is the outlet module, and 107 is the aging device.

[0041] Figure 5 Schematic diagram of a valved microreactor in some embodiments of the present invention. Figure 5 In the figure, 201 is the first feed port, 202 is the second feed port, 203 is the second feed pressure regulating device, 204 is the first feed pressure regulating device, 205 is the reaction chamber, 206 is the discharge port, 501 is the micropore, and 502 is the slit.

[0042] Figure 6 Schematic diagram of the correspondence between slits and micropores in a valve-type microreactor in some embodiments of the present invention. Figure 6 In the figure, 501 is a microhole and 502 is a slit.

[0043] Figure 7 This is the SEM image of the ternary positive electrode material precursor product prepared in Comparative Example 1.

[0044] Figure 8 This is the SEM image of the ternary positive electrode material precursor product prepared in Comparative Example 2.

[0045] Fig. 9 This is the SEM image of the ternary positive electrode material precursor product prepared in Example 1.

[0046] Fig.10 This is the SEM image of the ternary positive electrode material precursor product prepared in Example 3.

[0047] Fig.11This is the SEM image of the ternary positive electrode material precursor product prepared in Example 4.

[0048] Fig.12 This is the SEM image of the ternary positive electrode material precursor product prepared in Example 5. DETAILED DESCRIPTION

[0049] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used in the text are the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definition in this specification shall prevail.

[0050] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0051] Herein, “comprising”, “including”, “containing” and similar terms encompass the meanings of “consisting essentially of” and “consisting of”. For example, when “A comprises B and C” is disclosed herein, “A consists essentially of B and C” and “A consists of B and C” should be deemed to be disclosed herein.

[0052] In this article, all features such as values, quantities, contents and concentrations defined in the form of numerical ranges or percentage ranges are only for brevity and convenience. Accordingly, the description of numerical ranges or percentage ranges should be considered to have included and specifically disclosed all possible secondary ranges and individual values ​​within the range (including integers and fractions).

[0053] In this document, unless otherwise specified, percentage refers to mass percentage and ratio refers to mass ratio.

[0054] Herein, when describing embodiments or examples, it should be understood that they are not used to limit the present invention to these embodiments or examples. On the contrary, all substitutes, improvements and equivalents of the methods and materials described in the present invention can be included in the scope limited by the claims.

[0055] In this document, in order to make the description concise, not all possible combinations of various technical features in various embodiments or examples are described. Therefore, as long as there is no contradiction in the combination of these technical features, the various technical features in various embodiments or examples can be combined arbitrarily, and all possible combinations should be considered to be within the scope of this specification.

[0056] In order to solve the problem that the primary particles of the cathode material precursor prepared in a microchannel reactor are randomly agglomerated, resulting in difficulty in controlling the particle size, the present invention adopts measures such as adjusting the aging conditions and adding additives during the aging stage to achieve particle size control and morphology shaping of the cathode material precursor.

[0057] The method for preparing the ternary cathode material precursor of the present invention comprises the following steps:

[0058] (1) Co-precipitation reaction: a microchannel reactor is used to carry out a co-precipitation reaction to obtain a reaction solution containing a ternary cathode material precursor;

[0059] (2) Aging: Aging the reaction solution obtained in step (1);

[0060] (3) Post-treatment: The ternary cathode material precursor aged in step (2) is post-treated, and the post-treatment includes washing, dehydration, drying and crushing.

[0061] The present invention adopts a microchannel reactor to prepare a ternary positive electrode material precursor.

[0062] In the present invention, the ternary cathode material precursor refers to the hydroxide of nickel, cobalt, manganese or the hydroxide of nickel, cobalt, aluminum, and the chemical formula is Ni x Co y M z (OH) 2 , M is Mn or Al, 0<x<1, 0<y<1, 0<z<1, and x+y+z=1. The ternary cathode material precursor is in a granular form, also known as a ternary cathode material precursor particle.

[0063] Preferably, the chemical formula of the ternary cathode material precursor is Ni x Co y M z (OH) 2 wherein x is 0.6 to 0.95, for example, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, preferably 0.6 to 0.8, more preferably 0.6 to 0.7; y is 0 to 0.2, for example, 0.01, 0.05, 0.07, 0.1, 0.12, 0.15, preferably 0.05 to 0.15, more preferably 0.07 to 0.12; z is 0 to 0.3, for example, 0.01, 0.05, 0.07, 0.1, 0.15, 0.2, 0.25, 0.26, 0.28, preferably 0.15 to 0.3, more preferably 0.15 to 0.28.

[0064] The ternary positive electrode material precursor is generated by coprecipitation reaction of nickel salt, cobalt salt and aluminum salt or nickel salt, cobalt salt and manganese salt in the presence of a precipitant and a complexing agent. The raw materials for preparing the ternary positive electrode material precursor generally include: a salt solution of nickel cobalt aluminum or nickel cobalt manganese, a precipitant and a complexing agent. Among them, the precipitant and the complexing agent can be mixed and fed, or they can be fed separately. In the present invention, the salt solution of nickel cobalt manganese is a solution containing nickel salt, cobalt salt and manganese salt, and the salt solution of nickel cobalt aluminum is a solution containing nickel salt, cobalt salt and aluminum salt. Nickel salts, cobalt salts, manganese salts and aluminum salts suitable for the present invention may be nickel salts, cobalt salts, manganese salts and aluminum salts known to be used for preparing ternary positive electrode material precursors, including but not limited to nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and hydrates thereof. In some embodiments, hydrated nickel sulfate (e.g., NiSO 4 6H 2 O), hydrated cobalt sulfate (e.g. CoSO 4 7H 2 O) and hydrated manganese sulfate (e.g. MnSO 4 ·H 2 O) preparing a nickel-cobalt-manganese salt solution. In the nickel-cobalt-aluminum or nickel-cobalt-manganese salt solution, the total concentration of metal ions can be 1.5 to 2.5 mol / L, preferably 1.5 to 2 mol / L.

[0065] The precipitant may be a sodium hydroxide solution. The concentration of the sodium hydroxide solution may be 4 to 10 mol / L, preferably 4 to 8 mol / L. The complexing agent may be an aqueous ammonia solution. The concentration of the aqueous ammonia solution may be 3 to 10 mol / L, preferably 3 to 8 mol / L. In some embodiments, the complexing agent (e.g., aqueous ammonia solution) and the precipitant (e.g., sodium hydroxide solution) are mixed evenly to form a mixed solution, which is then reacted with a salt solution of nickel-cobalt-aluminum or nickel-cobalt-manganese.

[0066] Before the reaction, the reaction raw materials (such as nickel-cobalt-aluminum or nickel-cobalt-manganese salt solution, precipitant, complexing agent, mixed solution of precipitant and complexing agent) are preferably preheated to 30-80°C, preferably 40-70°C.

[0067] The reaction raw materials can be delivered to the microchannel reactor by a high-precision feed pump. The feed flow rate of the nickel-cobalt-aluminum or nickel-cobalt-manganese salt solution can be 50 to 400 kg / h, preferably 100 to 300 kg / h. The feed flow rate of the mixed solution of the precipitant and the complexing agent can be 50 to 400 kg / h, preferably 100 to 300 kg / h.

[0068] In some embodiments, a nickel-cobalt-aluminum or nickel-cobalt-manganese salt solution and a mixed solution of a precipitant and a complexing agent are rapidly mixed in a microchannel reactor to undergo a co-precipitation reaction to obtain a ternary cathode material precursor.

[0069] In step (1) of the present invention, it is preferred to use a valve microreactor to carry out a coprecipitation reaction to prepare a ternary positive electrode material precursor. In the present invention, the ternary positive electrode material precursor prepared using a valve microreactor as a place for the coprecipitation reaction is called an M ternary positive electrode material precursor. Therefore, in the present invention, the ternary positive electrode material precursor used for aging is preferably an M ternary positive electrode material precursor. The use of a valve microreactor to prepare an M ternary positive electrode material precursor has the advantages of high reaction efficiency and reduced control parameters.

[0070] In the present invention, microchannel reactor (also called microreactor) refers to a micro reactor with a characteristic size of 10 to 1000 microns, for example, 10 to 300 microns, manufactured by precision machining technology. The "micro" in microreactor means that the channel of the process fluid is at the micron level, rather than that the overall size of the micro reaction device is small or the output of the product is small.

[0071] The cathode material precursor preparation system (referred to as preparation system) of the present invention can be used to prepare M ternary cathode material precursor. The preparation system of the present invention includes at least two feeding systems and a valve microreactor, wherein the feeding system is used to provide reaction raw materials to the valve microreactor, and the valve microreactor is used to carry out a coprecipitation reaction. In some embodiments, the preparation system of the present invention also includes an aging device, which is used to age the product generated in the valve microreactor. Each feeding system and the valve microreactor and the valve microreactor and the aging device can be connected by a pipeline. The preparation system of the present invention can quickly complete the reaction, reduce the scrap rate, increase the production capacity, completely avoid the amplification effect, shorten the time from research and development to production of the cathode material precursor, and can accurately control the reaction conditions, and can produce products with stable quality and good consistency. The preparation system of the present invention has a simple start-stop reaction, is easy to clean, has a high degree of automation, a stable production process, and is extremely efficient.

[0072] In the present invention, as a reaction device for coprecipitation reaction, the valve-type microreactor can control the pressure of two or more feed liquids, achieve stable feeding and mixing reactions under large flow and high flow rate, ensure that high-concentration reaction products can be quickly removed, and realize continuous reaction without blockage.

[0073] like Figure 1As shown, in the present invention, the valve type microreactor includes a first feed port 201, a second feed port 202, a first feed pressure regulating device 204, a second feed pressure regulating device 203, a reaction chamber 205 and a discharge port 206. The first feed port 202 is connected to the reaction chamber 205 through a flow channel. The second feed port 202 is connected to the reaction chamber 205 through a flow channel. The first feed pressure regulating device 204 is arranged on the flow channel between the first feed port 201 and the reaction chamber 205. The second feed pressure regulating device 203 is arranged on the flow channel between the second feed port 202 and the reaction chamber 205. The discharge port 206 is connected to the reaction chamber 205.

[0074] Jet-type collision occurs between the various liquids entering the reaction chamber through each feed port of the valve microreactor. The end of the flow channel between the feed port and the reaction chamber (for example, the end of the flow channel between the first feed port 201 and the reaction chamber 205, the end of the flow channel between the second feed port 202 and the reaction chamber 205) is provided with a plurality of micropores and / or slits distributed in an annular manner. Herein, the end refers to the end along the flow direction of the feed liquid. Multiple refers to two or more. Annular distribution means that the micropores and / or slits can be regarded as distributed on a ring. Preferably, the micropores and / or slits are arranged so that the jets ejected from the ends of each flow channel correspond one to one, and collide and mix in real time. In some embodiments, the end of the flow channel between the first feed port 201 and the reaction chamber 205 is provided with a micropore, and the end of the flow channel between the second feed port 202 and the reaction chamber 205 is provided with a slit; preferably, the design of the micropores and slits makes the jets ejected from the ends of the two flow channels correspond one to one, and collide and mix in real time. Preferably, the end of the flow channel between the first feed port 201 and the reaction chamber 205 and the end of the flow channel between the second feed port 202 and the reaction chamber 205 are arranged so that materials ejected from the two flow channel ends collide tangentially in the reaction chamber 205 .

[0075] In the present invention, the first feed pressure regulating device 204 and the second feed pressure regulating device 203 are respectively used to control the feed pressure of the first feed port 210 and the second feed port 202, so that the materials of the two feed ports can be sprayed into the reaction chamber 205 according to the expected pressure, flow rate and flow rate. In a preferred embodiment, the materials of the two feed ports are sprayed into the reaction chamber 205 through the micropores and / or slits distributed in an annular shape according to the expected pressure, flow rate and flow rate, and the spray trajectories of the two materials in the reaction chamber 205 after passing through the micropores and / or slits correspond to each other, and a real-time tangential collision occurs to achieve uniform mixing and reaction, and then the product after the reaction flows out quickly through the discharge port 206 under the pressure and the rear negative pressure that preferably exists. In some embodiments, the first feed pressure regulating device or the second feed pressure regulating device includes a pressure valve, and the pressure valve automatically connects the flow channel between the feed port and the reaction chamber when the feed pressure reaches a certain value. In other embodiments, the first feed pressure regulating device or the second feed pressure regulating device includes a pressure gauge and a valve, and the pressure gauge monitors the feed pressure. When the feed pressure reaches a certain value, the pressure gauge directly controls the valve, or controls the valve through other devices such as a numerical control system to connect the flow channel between the feed port and the reaction chamber. In other embodiments, the first feed pressure regulating device or the second feed pressure regulating device also includes a booster pump. When the feed pressure does not reach the set value, the booster pump pressurizes the feed liquid so that the feed pressure reaches the required value. The flow rate and flow velocity of the feed liquid can be adjusted by regulating the pressure of the feed liquid.

[0076] In the present invention, Figure 1 As shown, the reaction chamber 205 is preferably semi-ellipsoidal, and the discharge port 206 is preferably bell-bottomed. The bell-bottomed discharge port 206 is connected to the opening of the semi-ellipsoidal reaction chamber 205, so that high-concentration reaction products can be quickly discharged, and continuous reaction can be achieved without blockage.

[0077] The valve-type microreactor in the present invention realizes stable feeding and mixing reaction under large flow and high flow rate by setting the first feeding pressure regulating device 204 and the second feeding pressure regulating device 203; by setting a plurality of micropores and / or slits, the jet flow collision route is reasonable, the micropore jet flow corresponds to the slit jet flow one by one, and the collision and mixing are carried out in real time, so that a very high mixing and reaction effect can be achieved in the reaction chamber 205; the reaction chamber 205 is designed to be semi-ellipsoidal, and the discharge port 206 is in a bell-bottomed release state. The reasonable design can ensure that the high-concentration reaction products can be quickly discharged, and continuous reaction can be achieved without blockage.

[0078] The valve type microreactor in the present invention may include a T-type microchannel reactor or a cluster microchannel reactor.

[0079] In the present invention, the feeding system includes a feeding device that can accurately, evenly and stably realize solution filtration, metering, pressure regulation, and liquid delivery according to the pipeline and valve direction. In some embodiments, the feeding system includes a feeding device, a mass flow meter, a pressure controller and a valve, the valve includes an inlet and a first outlet, and the feeding system also includes an inlet pipeline connected to the inlet of the valve and a first outlet pipeline connected to the first outlet of the valve, the feeding device, the mass flow meter and the pressure controller are arranged on the inlet pipeline, and the valve communicates with the inlet pipeline and the first outlet pipeline when the flow detected by the mass flow meter and the pressure detected by the pressure controller meet the set value. The feeding device may include a gear feeding device or a delivery pump. The delivery pump may be a gear pump, a diaphragm pump or a peristaltic pump. Each feeding system may be the same or different. The first outlet pipeline of the feeding system may be directly connected to the valve microreactor, or may be connected to other devices, systems or modules (such as heating modules, mixing modules) arranged between the feeding system and the valve microreactor. The inlet pipeline of the feeding system may be connected to a raw material tank or a washing water tank. The valve may be a reversing valve, including two or more outlets. Each outlet of the valve may be connected to an outlet pipe. The second outlet pipe connected to the second outlet of the valve may be connected to a raw material tank or a washing water tank, so that the material flow or pressure does not meet the set requirements and returns to the raw material tank or the washing water tank.

[0080] In the present invention, the aging device is a place where the reaction product of the valve-type microreactor is further aged. The aging device applicable to the present invention can be an aging device commonly used in the art, such as an aging kettle.

[0081] The preparation system of the present invention preferably includes a negative pressure system arranged between the valve type microreactor and the aging device. The negative pressure system is used to form a negative pressure at the outlet end of the valve type microreactor. All devices or device combinations that can ensure that the reaction products of the mixed reaction of the reactants in the microchannel reactor and the outlet end can be timely removed under the action of the feed pressure and the rear end negative pressure, and ensure that the microchannel reactor can run smoothly without clogging under the reaction condition line of large flow and high pressure can be used as the negative pressure system. In some embodiments, the negative pressure system includes a vacuum pump and a vacuum negative pressure tank.

[0082] In some embodiments, such as Figure 2As shown, the preparation system of the present invention includes a first feeding system 101, a second feeding system 102, a valve microreactor 104, a negative pressure system and an aging device 107. The negative pressure system includes a vacuum negative pressure tank 105 and a vacuum pump 106. The vacuum negative pressure tank 105 is arranged between the valve microreactor 104 and the aging device 107, and is connected to the valve microreactor 104 and the aging device 107 through a pipeline. The first feeding system 101 and the second feeding system 102 are respectively connected to the valve microreactor 104 through a pipeline. The vacuum pump 106 is connected to the vacuum negative pressure tank 105 through a pipeline. The vacuum pump 106 and the vacuum negative pressure tank 105 are used in combination to ensure that a certain negative pressure or normal pressure can always be stably maintained in the vacuum negative pressure tank 105. The negative pressure value in the vacuum negative pressure tank 105 can be adjusted according to the flow rate, concentration of the reactants in the front-end valve type microreactor 104 and the flow rate and concentration, viscosity and solid content of the reaction product, so as to ensure that the reaction product in the valve type microreactor 104 can be removed in time under the action of the feed pressure and the rear-end negative pressure, and ensure that the valve type microreactor 104 can run smoothly without clogging under the reaction conditions of large flow and high pressure. The negative pressure system can be adjusted accordingly depending on the specific reaction situation. The aging device 107 is an aging kettle. The aging kettle is used to age the product under conditions such as stirring at a certain speed and heat preservation.

[0083] In some embodiments, the feed system includes a feeder, a mass flowmeter, a pressure controller and a reversing valve. The reversing valve includes an inlet and at least two outlets. The feed system includes an inlet pipeline connected to the inlet of the reversing valve, a first outlet pipeline connected to the first outlet of the reversing valve, and a second outlet pipeline connected to the second outlet of the reversing valve, the feeder, the mass flowmeter and the pressure controller are arranged on the inlet pipeline, and the reversing valve communicates the inlet pipeline and the first outlet pipeline when the flow detected by the mass flowmeter and the pressure detected by the pressure controller meet the set value. The feeder can be a delivery pump, such as a gear pump, a diaphragm pump or a peristaltic pump. The first outlet pipeline can be connected to the valve microreactor. The second outlet pipeline can be connected to a raw material tank or a washing water tank.

[0084] In some embodiments, such as Figure 3As shown, the preparation system of the present invention includes a first feeding system 101, a second feeding system 102, a valve microreactor 104, a vacuum negative pressure tank 105, a vacuum pump 106, an aging device 107, a first raw material tank 108, a first washing water tank 109, a second raw material tank 110 and a second washing water tank 111. Wherein, the first feeding system 101 includes a first feeding device 301, a first mass flowmeter 302, a first pressure controller 303 and a first reversing valve 304, and the second feeding system 102 includes a second feeding device 401, a second mass flowmeter 402, a second pressure controller 403 and a second reversing valve 404. The reversing valve has a feed port, a discharge port, a raw material reflow port and a washing water reflow port. The feed port of the reversing valve is connected to a feed pipe. The raw material tank and the washing water tank are connected to the feed pipe. The feeding device, the mass flowmeter and the pressure controller are arranged on the feed pipe. The discharge port of the reversing valve is connected to the valve microreactor 104 through a pipeline. The raw material reflux port of the reversing valve is connected to the raw material tank through a pipeline. The washing water reflux port of the reversing valve is connected to the washing water tank through a pipeline. The feeding device is a gear pump. The main function of the gear pump is to deliver liquid raw materials of a specific flow rate and pressure according to the set flow rate. The mass flow meter measures the flow rate in real time and feeds back the flow rate information in time. The pressure control device monitors the liquid pressure in real time and sets the required liquid pressure. When the feeding system is started, before the flow rate and pressure reach the set flow rate and pressure, the reversing valve can be set (for example, controlled by a control system) to allow the raw materials to enter from the feed port and return to the raw material tank from the raw material reflux port to form a cycle to prevent the waste of raw materials. When the flow rate and pressure meet the process requirements, the reversing valve can be set to allow the reaction raw materials to enter the valve microreactor 104 from the discharge port, fully mix and react quickly, and quickly enter the vacuum negative pressure tank 105. After a certain amount is stored, it enters the aging device 107 for a certain period of aging. After the reaction is completed, the washing water in the washing water tank is passed into the feeding system and the valve type microreactor 104 to achieve rapid washing of the feeding system and the valve type microreactor 104. A reversing valve can be arranged between the raw material tank and the washing water tank and the feeding pipeline, and the reversing valve can have a raw material inlet, a washing water inlet and an outlet. The raw material inlet of the reversing valve is connected to the raw material tank through a pipeline, the washing water inlet of the reversing valve is connected to the washing water tank through a pipeline, and the outlet of the reversing valve is connected to the feeding pipeline.

[0085] In some embodiments, the preparation system of the present invention further includes a control system, such as a numerical control system. The control system is used to receive process parameters such as flow rate and pressure measured by detection devices such as flow meters and pressure gauges, and control the operation of working devices such as valves (such as reversing valves), pumps (such as booster pumps, vacuum pumps), and feeding devices according to the received process parameters. The control system can be connected to other systems, devices, equipment, modules, components, etc. in the preparation system of the present invention, such as a feeding system and a valve-type microreactor in a wired or wireless manner.

[0086] The preparation system of the present invention may also include a heating module arranged between one or more feed systems and the valve microreactor. The heating module is used to preheat the material entering the valve microreactor. The heating module can be combined with the valve microreactor, for example, the heating module is arranged before the feed port of the valve microreactor, and the reaction raw materials are heated to the temperature required by the process before entering the valve microreactor. In some embodiments, the preparation system of the present invention includes at least three feed systems and a mixing module arranged between at least two feed systems and the valve microreactor, and the mixing module is used to mix the reaction raw materials from the at least two feed systems and provide the mixed reaction raw materials to the valve microreactor. The mixing module may include a stacked mixer, a valve mixer, a T-type microchannel reactor or a clustered microchannel reactor.

[0087] In some embodiments, such as Figure 4 As shown, the preparation system of the present invention includes a first raw material tank 108, a second raw material tank 110, a third raw material tank 112, a first feeding system 101, a second feeding system 102, a third feeding system 103, a first inlet module 114, a first heating module 115, a second inlet module 116, a third inlet module 117, a mixing module 119, a second heating module 120, a valve microreactor 104, an outlet module 121, an aging device 107 and a negative pressure system ( Figure 6 107 is an aging kettle, and the mixing module 119 is a stacked mixer. The negative pressure system includes a vacuum negative pressure tank and a negative pressure pump, the vacuum negative pressure tank is arranged between the outlet module 121 and the aging device 107, and the negative pressure pump is connected to the vacuum negative pressure tank. In the present invention, the inlet module and the outlet module can be simple inlet and outlet connection modules.

[0088] In some embodiments, such as Figure 5As shown, the valve type microreactor used in the present invention includes a first feed port 201, a second feed port 202, a first feed pressure regulating device 204, a second feed pressure regulating device 203, a reaction chamber 205, a discharge port 206, a micropore 501 and a slit 502. The first feed pressure regulating device 204 is arranged on the flow channel between the first feed port 201 and the reaction chamber 205. The second feed pressure regulating device 203 is arranged on the flow channel between the second feed port 202 and the reaction chamber 205. The reaction chamber 205 is semi-ellipsoidal. The discharge port 206 is flared. The discharge port 206 of the flared trousers is connected to the opening of the semi-ellipsoidal reaction chamber 205, so that the high-concentration reaction product can be quickly discharged, and continuous reaction can be achieved without blockage. Looking at the reaction chamber 205 from the discharge port 206, the cross section of the reaction chamber 205 is elliptical, indicating that the reaction chamber 205 is semi-ellipsoidal. The micropore 501 is disposed at the end of the flow channel between the first feed port 201 and the reaction chamber 205 . The slit 502 is disposed at the end of the flow channel between the second feed port 202 and the reaction chamber 205 .

[0089] A jet-like collision occurs between the various liquids entering the reaction chamber through the various feed ports of the valve-type microreactor. The end of the flow channel between the feed port and the reaction chamber (for example, the end of the flow channel between the first feed port 201 and the reaction chamber 205, the end of the flow channel between the second feed port 202 and the reaction chamber 205) is provided with a plurality of micropores and / or slits distributed in an annular shape. Preferably, the micropores and / or slits are arranged so that the jets ejected from the two flow channel ends correspond to each other one by one, and collide and mix in real time. In some embodiments, such as Figure 5 and Figure 6 As shown, a micropore 501 is provided at the end of the flow channel between the first feed inlet 201 and the reaction chamber 205, and a slit 502 is provided at the end of the flow channel between the second feed inlet 202 and the reaction chamber 205. Preferably, as Figure 6 As shown, the design of micropores 501 and slits 502 allows the jets ejected from the two flow channel ends to correspond to each other and collide and mix in real time. Figure 6 As shown, each micropore 501 is evenly distributed in an annular shape, and each slit 502 is also evenly distributed in an annular shape and corresponds to each micropore 501 one by one, so that the jets sprayed into the reaction chamber 205 from the two flow channel ends can correspond to each other one by one and collide and mix in real time. Preferably, the end of the flow channel between the first feed port 201 and the reaction chamber 205 and the end of the flow channel between the second feed port 202 and the reaction chamber 205 are arranged so that the materials sprayed from the two flow channel ends collide tangentially in the reaction chamber 205.

[0090] In some embodiments, such as Figure 5 and Figure 6As shown, the diameter of the micropore 501 is 10-100 μm, such as 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, and the gap of the slit 502 is 100-200 μm, such as 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm. The above-mentioned size design of the micropore and the slit is conducive to the high-speed injection of the material flow, realizing real-time collision mixing and quickly completing the reaction. In this article, the gap of the slit refers to the gap width of the slit.

[0091] In the present invention, Figure 5 As shown, the reaction chamber 205 is preferably semi-ellipsoidal, and the discharge port 206 is preferably bell-bottomed. The bell-bottomed discharge port 206 is connected to the opening of the semi-ellipsoidal reaction chamber 205, so that high-concentration reaction products can be quickly discharged, and continuous reaction can be achieved without blockage.

[0092] The preparation system of the present invention may optionally further include one or more or all of the following equipment or devices: a centrifugal device, a washing device, a filtering device, a drying device, a mixing device, a screening device, a demagnetizing device, and a packaging device. The centrifugal device is used to centrifugally dry the aged positive electrode material precursor slurry. The centrifugal device can be a centrifuge. The washing device is used to perform alkali washing, water washing and other washing operations on the positive electrode material precursor after centrifugal drying. After washing, the filter device is used for filtering. The filter cake is dried into powder particles by a drying device. The drying device can be a dynamic drying device. The dried powder particles enter the mixing device in batches for uniform mixing. The mixing device can be a mixer. The mixed powder is passed through a screening device, such as a screen, to remove large particles that are bonded, and then the magnetic substances in the powder particles are removed by a demagnetizing device, such as a demagnetizer, and finally packaged and packaged into a positive electrode material precursor product by a packaging device, such as a vacuum packaging machine.

[0093] The M ternary positive electrode material precursor of the present invention can be prepared using the preparation system of the present invention. The preparation method can completely avoid the amplification effect, shorten the time from research and development to production of the positive electrode material precursor, and can achieve precise control, and can produce products with stable quality and good consistency. The preparation method of the present invention has a simple start-stop reaction, and the production process greatly reduces the generation of waste and energy consumption compared to traditional production processes.

[0094] In some embodiments, the method for preparing M ternary cathode material precursor includes: providing at least two reaction raw materials to a valve microreactor through a feeding system, allowing each reaction raw material to undergo a co-precipitation reaction in the valve microreactor after passing through a feeding pressure regulating device.

[0095] In some embodiments, the present invention uses Figure 3The preparation system shown prepares M ternary positive electrode material precursor. The salt solution of nickel-cobalt-aluminum or nickel-cobalt-manganese-aluminum is configured according to the process requirements, stored in the first raw material tank 108 and kept warm, and the precipitant (such as sodium hydroxide) and the complexing agent (such as ammonia water) are stirred and mixed uniformly in the second raw material tank 110 according to the proportion and concentration required by the process, and stored warm. Then the feeding devices 301 and 401 are started. Before the flow rate and pressure reach the set flow rate and pressure, valves 304 and 404 can be set to allow the raw materials to enter the feed port of the valve and return to the first raw material tank 108 and the second raw material tank 110 from the reflux port to form a cycle, and the waste of raw materials is eliminated. When the flow rate and pressure meet the process requirements, the reaction raw materials can be switched according to the process. Pipeline 104, fully mixed and quickly reacted to generate M ternary positive electrode material precursor, and then quickly enter the vacuum negative pressure tank 105, after a certain amount of storage, it is placed in the aging device 107 for a certain period of aging. After the reaction is completed, the washing water in the first washing water tank 109 and the second washing water tank 111 is quickly introduced into the first feeding system 101, the second feeding system 102 and the valve microreactor 104 to achieve rapid washing. In the present invention, the flow rate setting value of the feed liquid can be 6-720L / h, such as 10L / h, 20L / h, 50L / h, 100L / h, 200L / h, 500L / h, and the pressure setting value can be 3-30bar, such as 5±0.5bar, 8±0.5bar, 10±0.5bar, 15±0.5bar, 20±0.5bar, 25±0.5bar.

[0096] In some embodiments, the present invention uses Figure 4The preparation system shown prepares M ternary positive electrode material precursor. First, nickel salt, cobalt salt and aluminum salt, or nickel salt, cobalt salt and manganese salt are dissolved into a mixed salt solution of a certain concentration and molar ratio according to the process requirements, and stored in the first raw material tank 108, wherein the total concentration of metal elements can be 0.5-2.2mol / L, for example, 0.8mol / L, 1mol / L, 1.2mol / L, 1.5mol / L, 1.8mol / L, 2mol / L, and the higher the concentration, the greater the production capacity in the corresponding time. In the present invention, when the salt solution contains multiple metal elements, the concentration of metal elements in the salt solution refers to the total concentration of all metal elements. For example, for a mixed salt solution of nickel salt, cobalt salt and manganese salt, the concentration of metal elements refers to the total concentration of nickel, cobalt and manganese. The precipitant and the complexing agent are stored in the second raw material tank 110 and the third raw material tank 112, respectively. The concentration of the precipitant (such as sodium hydroxide solution) can be configured to 2-10mol / L according to the specific process requirements, such as 3mol / L, 4mol / L, 5mol / L, 6mol / L, 7mol / L, 8mol / L, 9mol / L. The concentration of the complexing agent (such as ammonia water) can be 2-10mol / L, such as 3mol / L, 4mol / L, 5mol / L, 6mol / L, 7mol / L, 8mol / L, 9mol / L. The higher the concentration, the greater the product capacity at the corresponding time, and the higher the solid content. The precipitant (such as sodium hydroxide solution) and the complexing agent (such as ammonia water) can be stored in the same raw material tank, but it is more conducive to adjusting the pH of the reaction system to store and feed the precipitant and the complexing agent separately. Then, the first feeding system 101 injects the salt solution into the first heating module 115 through the first inlet module 114 according to the process setting flow rate (the production flow rate can be 6-720L / h), and heats it to a certain temperature, generally 30-65°C, through the heating module. The second feeding system 102 and the third feeding system 103 respectively inject the precipitant and the complexing agent into the mixing module 119 (for example, a stacked mixer) according to the process required flow rate (the production flow rate can be 6-720L / h) through the second inlet module 116 and the third inlet module 117 to fully mix the multiple strands of materials, and quickly heat the raw material liquid in the channel to the temperature required by the process, generally 30-65°C, through the second heating module 120, and then directly pass into the valve microreactor 104. The feed pressure can be 3-30bar, for example, 5±0.5bar, 8±0.5bar, 10±0.5bar, 15±0.5bar, 20±0.5bar, 25±0.5bar. Each heating module is combined with the valve microreactor 104, and the heating module is arranged before the feed port of the valve microreactor to heat the corresponding reaction raw materials to the temperature required by the process before entering the valve microreactor. The salt solution is introduced into the valve microreactor 104 to be fully mixed and reacted with the remaining reaction raw materials entering the valve microreactor 104 from another feed port to generate M ternary positive electrode material precursor.In the real-time reaction process of preparing the M ternary cathode material precursor, the molar ratio of ammonia to metal elements in the reaction system in any instantaneous mixed reaction stage is a fixed value, which is between 0-1. For different series of products, the optimal value interval of the ratio of ammonia to metal elements is different; the molar ratio of sodium hydroxide to metal elements is between 2.2:1 and 1.8:1, ensuring that the pH value is stable during instantaneous reaction, and for different series of products, the optimal value is different, and the optimal value range is between 10-12.5. The preparation method of the present invention makes full use of the efficient mass transfer, heat transfer and mixing performance of the valve microreactor, and quickly mixes the materials evenly in a short time to make it react quickly. The final product flows out to the subsequent aging device 107 (such as aging kettle) via the outlet module 121. After a period of aging, the slurry is pumped into a centrifuge for centrifugal drying, alkali washing, water washing and other washing operations to reduce the content of impurities such as ammonia nitrogen, sodium, and sulfate in the product. The filter cake is then dried continuously and regularly at a fixed process temperature by a dynamic drying device into loose powder particles, which are then fed into a mixer in batches for uniform mixing, and then passed through a screen to remove large particles that are bonded, and then passed through a demagnetizer to remove magnetic substances from the powder particles, and finally packaged and packaged into a qualified positive electrode material precursor by a vacuum packaging machine. In some embodiments, a negative pressure system is provided before aging, and the product first enters a vacuum negative pressure tank and then enters an aging device.

[0097] The M ternary positive electrode material precursor has the advantages of stable quality and good consistency. The M ternary positive electrode material precursor is a secondary particle composed of primary particles of nanometer scale (≤100nm). The particle size of the primary particles of the M ternary positive electrode material precursor is between 10nm-100nm, for example, 20nm, 25nm, 30nm, 40nm, 50nm, 60nm, 70nm, 80nm, 90nm, and the preferred particle size is between 30nm-100nm. In the present invention, the particle size of the primary particles of the M ternary positive electrode material precursor is nanometer scale (≤100nm), while the particle size of the primary particles of the conventional ternary positive electrode material precursor is subnanometer scale to micrometer scale (hundreds of nanometers to several microns). The particle size D50 of the secondary particles of the M ternary positive electrode material precursor can be between 2 μm and 20 μm, such as 3 μm, 5 μm, 7 μm, 10 μm, 12 μm, 15 μm, 18 μm, preferably between 2 μm and 8 μm. The specific surface area of ​​the M ternary positive electrode material precursor is 35-150 m 2 / g, preferably 50-110m 2 / g, for example 60m 2 / g, 70m 2 / g, 80m 2 / g, 90m 2 / g、100m 2 / g, which is 7-10 times that of conventional ternary cathode material precursors (the specific surface area of ​​conventional ternary cathode material precursors is generally 5-15m2 / g). The shape of the secondary particles of the M ternary positive electrode material precursor is an irregular shape formed by loosely overlapping primary particles. Herein, the irregular shape includes but is not limited to rod-shaped, disc-shaped, arch-shaped, star-shaped, elliptical, polygonal or any other irregular shape and a mixture of these shapes. Compared with spherical secondary particles, irregularly shaped secondary particles have a larger specific surface area, which is conducive to the rapid and uniform sintering of the positive electrode material precursor and the lithium source into a positive electrode material.

[0098] In the present invention, the material after the coprecipitation reaction enters the aging device through the discharge port of the microchannel reactor (e.g., valve-type microreactor) for aging. The aging device can be an aging kettle. The aging process is preferably protected by nitrogen. The material can be allowed to enter the aging device by continuous overflow.

[0099] In the prior art, no additional control is generally performed during the aging stage. After aging for a period of time (eg, 30 minutes to several hours) under constant temperature and stirring conditions, the mother liquor removal and washing operation is directly performed.

[0100] In the present invention, the ternary cathode material precursor prepared by the microchannel reactor has an extremely fast reaction rate, and there is nucleation during the reaction process. The nucleation rate in the reaction solution is much greater than the growth rate, and the primary particles are randomly agglomerated, which makes it difficult to control the particle size of the grains and significantly reduces the stability of the crystals, affecting the cycle stability of the cathode material prepared by subsequent sintering. The existing technology mainly slows down the growth process of the crystal by reducing the concentration of the reaction solution or reducing the feed flux, which significantly reduces the production efficiency.

[0101] In order to solve the problem of random agglomeration of primary particles and corresponding particle size control, after rapid nucleation in the reaction section of the microchannel reactor, the present invention regulates the agglomeration process of the primary particles by controlling the pH value of the reaction solution or adding an additive to the reaction solution in the aging stage, thereby controlling the particle size to an ideal value and improving the tap density of the particles (≥1.3 g / mL), thereby improving product performance.

[0102] In the present invention, the main purpose of the aging process is to promote the growth of crystal nuclei and improve the uniformity of primary particle agglomerates. The present invention controls the pH value of the reaction solution to 9.5-12.5 or adds an auxiliary agent to the reaction solution before aging, thereby achieving control of the particle size of the primary particle agglomerates and the tap density of the positive electrode material precursor.

[0103] In the present invention, the insulation temperature of the aging process can be 25-80°C, preferably 30-65°C, such as 55-65°C, 60±2°C, 60±1°C, 60±0.5°C.

[0104] In the present invention, the aging time can be 2 to 12 hours, for example, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, and 11 hours.

[0105] During the aging process, nitrogen can be passed into the aging device, and the nitrogen flow rate is preferably 5 to 10 L / min, such as 6 L / min, 7 L / min, 8 L / min, and 9 L / min.

[0106] During the aging process, the reaction solution may be stirred, and the stirring speed is preferably 80 to 100 rpm, such as 85 rpm, 90 rpm, or 95 rpm.

[0107] In some embodiments, the present invention controls the pH value of the reaction solution to 9.5 to 12.5 before aging, preferably 9.5 to 12.1, such as 10, 10.5, 11, 11.5, 12. Controlling the pH value of the reaction solution within the aforementioned range before aging can increase the tap density of the positive electrode material precursor.

[0108] In other embodiments, the present invention adds an auxiliary agent to the reaction solution before aging. The added auxiliary agents and their action principles are divided into: (1) surfactants, such as sodium dodecylbenzene sulfonate, quaternary ammonium compounds, etc., which regulate the growth of crystal nuclei by reducing surface energy and other methods; (2) ammonium salts, such as ammonium sulfate, ammonium bisulfate, ammonium carbonate, ammonium bicarbonate, ammonium dihydrogen phosphate, etc., which control the movement of the reaction equilibrium direction by increasing the concentration of ammonium ions, thereby achieving the regulation of crystal growth; (3) pH regulators, such as acidic sodium sulfate (i.e., sodium bisulfate), sodium dihydrogen phosphate, aluminum chloride, etc., regulate the pH of the reaction solution by adding acidic or alkaline salts, thereby changing the pH conditions for grain growth and achieving a balance between nucleation rate and growth rate. The present invention finds that adding auxiliary agents to the reaction solution and then aging it can increase the tap density of the positive electrode material precursor. In the present invention, when adding an auxiliary agent, the mass ratio of the reaction solution to the auxiliary agent can be (10-200):1, preferably (20-100):1, more preferably (40-60):1, for example 45:1, 50:1, 55:1. In a preferred embodiment, the auxiliary agent is ammonium sulfate and / or sodium bisulfate.

[0109] The present invention optimizes the aging process after the reaction, controls the agglomeration of primary particles during growth by adjusting the pH value of the reactor or adding an auxiliary agent to the reaction solution, optimizes the particle size distribution of the product, and improves the tap density and processing performance of the product.

[0110] In some embodiments, post-processing comprises the following steps:

[0111] (3-1) Dehydration: Use a centrifuge or filter press to remove the mother liquor from the aged slurry;

[0112] (3-2) Washing: using water at 50-80°C, preferably 60-80°C, for example 70°C, and in a water:material mass ratio of (5-15):1, preferably (6-12):1, for example 8:1, 10:1, the water and the material are sequentially put into a beating kettle for stirring and beating, the beating time is 30-120 min, preferably 45-90 min, for example 60 min, 70 min, 80 min, the stirring speed is 50-200 rpm, preferably 60-150 rpm, for example 80 rpm, 100 rpm, 120 rpm, 140 rpm;

[0113] (3-3) Dehydration: Use a pneumatic diaphragm pump to pump the ternary cathode material precursor slurry into a centrifuge or filter press for dehydration;

[0114] (3-4) repeating the washing step (3-2) and the dehydration step (3-3), with the total number of washings being ≥ 2 times, until the pH of the washing water is ≤ 9.5;

[0115] (3-5) Drying and crushing: The washed and dehydrated material is dried in an oven and then ground and crushed to obtain a ternary cathode material precursor product.

[0116] The ternary cathode material precursor prepared by the present invention may have one or more of the following characteristics:

[0117] The Dmin of the ternary cathode material precursor is 0.8 to 1.6 μm, for example, 0.9 μm, 1.0 μm, 1.1 μm, 1.2 μm, 1.3 μm, 1.4 μm, 1.5 μm;

[0118] The D10 of the ternary cathode material precursor is 1.8 to 3.2 μm, for example, 2.0 μm, 2.2 μm, 2.4 μm, 2.6 μm, 2.8 μm, 3.0 μm;

[0119] The D50 of the ternary cathode material precursor is 5 to 19 μm, for example, 8 μm, 10 μm, 12 μm, 14 μm, 16 μm, 18 μm, 18.5 μm;

[0120] The D90 of the ternary cathode material precursor is 20 to 60 μm, for example, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm,;

[0121] The tap density of the ternary positive electrode material precursor is 1.3 to 1.8 g / mL, for example, 1.33 g / mL, 1.32 g / mL, 1.35 g / mL, 1.4 g / mL, 1.5 g / mL, 1.6 g / mL, 1.65 g / mL, and 1.7 g / mL.

[0122] The ternary positive electrode material can be prepared by sintering the ternary positive electrode material precursor of the present invention.

[0123] The present invention provides a solution for controlling the particle size of a ternary cathode material precursor prepared by a microchannel reactor by adjusting aging conditions, adding additives during the aging process, and the like. By changing the moving direction of the equilibrium, the relative speed of the nucleation rate and the growth rate, and the directional control of the agglomeration of the primary particles during the growth process, the particle size distribution of the product is optimized, the product tap density and processing performance are improved, and the structural stability of the crystal is improved. The method provided by the present invention has significant advantages over methods such as reducing the flux and the concentration of the reaction solution and re-granulating in the post-processing stage, and can solve the problem of difficulty in controlling the particle size due to random agglomeration of the primary particles of the ternary cathode material precursor prepared by the microchannel reactor.

[0124] The present invention will be described below in the form of specific examples. It should be understood that these examples are merely illustrative and are not intended to limit the scope of the present invention. The methods, reagents and materials used in the examples are, unless otherwise stated, conventional methods, reagents and materials in the art. The raw material compounds in the examples can all be purchased through commercial routes.

[0125] In the present invention, the testing method of particle size parameters such as Dmin, D10, D50, and D90 is as follows: adding the material to be tested into a dispersant, and using a Bruker laser particle size analyzer to detect the particle size distribution curve of the material under the condition of an ultrasonic intensity of 20-80%, and the instrument automatically generates corresponding parameters.

[0126] In the present invention, the testing method of tap density is: put the powder to be tested into a container, tap it until the volume of the powder in the container does not decrease, read the volume of the powder, divide the weight of the powder by the volume to obtain the tap density, repeat three times and take the average value.

[0127] Comparative Example 1

[0128] This comparative example adopts the following steps to prepare the ternary positive electrode material precursor:

[0129] (1) Coprecipitation reaction

[0130] use Figure 4 The preparation system shown in FIG. 1 is used to prepare the M ternary cathode material precursor, wherein the valve microreactor is constructed as shown in FIG. Figure 1 , Figure 5 and Figure 6 As shown, the diameter of the micropore 501 is 50 μm, the gap of the slit 502 is 150 μm, and the structure of the feeding system is as follows Figure 3 As shown, the preparation system includes Figure 4The negative pressure system shown in the figure includes a vacuum negative pressure tank and a negative pressure pump. The vacuum negative pressure tank is arranged between the outlet module 121 and the aging device 107. The negative pressure pump is connected to the vacuum negative pressure tank. The aging device 107 is an aging kettle.

[0131] NiSO 4 6H 2 O. CoSO 4 7H 2 O and MnSO 4 ·H 2 A mixed solution of various salts prepared into a certain concentration and molar ratio is stored in a salt storage tank (the first raw material tank 108), wherein the total concentration of metal elements is 2 mol / L, and the molar ratio of nickel, cobalt and manganese metal elements is 65:9:26.

[0132] Sodium hydroxide and ammonia water are prepared into a sodium hydroxide solution and an ammonia solution of a certain concentration, which are stored in an alkali storage tank (the second raw material tank 110) and an ammonia storage tank (the third raw material tank 112) respectively. The sodium hydroxide concentration c(NaOH) is 8 mol / L, and the ammonia concentration c(NH 3 ·H 2 O) is 5 mol / L.

[0133] The second feeding system 102 and the third feeding system 103 feed the ammonia solution and the sodium hydroxide solution at flow rates of 33.6 L / h and 98.4 L / h respectively according to the process requirements and a feed pressure of 8 bar, and then enter the mixing module 119 (stacked mixer) through the second inlet module 116 and the third inlet module 117 to fully mix the two streams of materials. The raw material liquid in the channel is quickly heated to the process required 45°C through the second heating module 120, and then introduced into the valve microreactor 104.

[0134] The first feeding system 101 feeds a metal salt solution with a total concentration of 2 mol / L and a molar ratio of nickel, cobalt, and manganese metal elements of 65:9:26 into the first heating module 115 through the first inlet module 114 according to the process setting flow rate of 168 L / h and a feed pressure of 8 bar. After being heated to 45° C. by the heating module, it is introduced into the valve microreactor 104 and fully mixed with the mixed solution of ammonia solution and sodium hydroxide solution entering the valve microreactor 104 from the other side to generate the ternary positive electrode material precursor Ni 0.65 Co 0.09 Mn 0.26 (OH) 2 .

[0135] (2) No aging is performed.

[0136] (3) Post-processing

[0137] The mother liquor of the ternary cathode material precursor reaction liquid obtained in step (1) is removed by a centrifuge; hot pure water at 80°C is used, and the water and the material are sequentially put into a pulping kettle in a water: material ratio of 10:1 for stirring and pulping, the pulping time is 60 minutes, and the stirring speed is 100 rpm; the precursor slurry after pulping is pumped into a centrifuge for dehydration by a pneumatic diaphragm pump; the dehydrated material is washed and dehydrated for a total of 3 times, and the pH of the last washing water is ≤9.5; the washed material is dried in an oven and then ground and pulverized to obtain a ternary cathode material precursor product, whose SEM image is shown as follows Figure 7 shown.

[0138] Comparative Example 2

[0139] This comparative example adopts the following steps to prepare the ternary positive electrode material precursor:

[0140] (1) The coprecipitation reaction steps are the same as those in Comparative Example 1.

[0141] (2) Aging

[0142] The ternary cathode material precursor reaction liquid obtained in step (1) is continuously overflowed into the aging kettle for aging, and N 2 protection, the nitrogen flow rate was controlled at 8 L / min, the aging temperature was 60±0.5°C, the stirring speed was 90 rpm, the aging time was 2 h, and the pH of the reaction solution was 12.8.

[0143] (3) Post-processing

[0144] The mother liquor of the ternary cathode material precursor reaction liquid after aging in step (2) is removed by a centrifuge; hot pure water at 80°C is used, and the water and the material are sequentially put into a pulping kettle in a water: material ratio of 10:1 for stirring and pulping, the pulping time is 60 minutes, and the stirring speed is 100 rpm; the precursor slurry after pulping is pumped into a centrifuge for dehydration by a pneumatic diaphragm pump; the dehydrated material is washed and dehydrated for a total of 3 times, and the pH of the last washing water is ≤9.5; the washed material is dried in an oven and then ground and pulverized to obtain a ternary cathode material precursor product, whose SEM image is shown as follows Figure 8 shown.

[0145] Comparative Example 3

[0146] This comparative example adopts the following steps to prepare the ternary positive electrode material precursor:

[0147] (1) The coprecipitation reaction steps are the same as those in Comparative Example 1.

[0148] (2) Aging

[0149] The ternary cathode material precursor reaction liquid obtained in step (1) is continuously overflowed into the aging kettle for aging, and N2 protection, the nitrogen flow rate was controlled at 8 L / min, the aging temperature was 60±0.5°C, the stirring speed was 90 rpm, the aging time was 5 h, and the pH of the reaction solution was 12.8.

[0150] (3) Post-processing

[0151] The mother liquor of the ternary cathode material precursor reaction liquid after aging in step (2) is removed by a centrifuge; hot pure water at 80°C is used, and the water and the material are sequentially put into a pulping kettle for stirring and pulping according to a water: material ratio of 10:1, the pulping time is 60 minutes, and the stirring speed is 100 rpm; the precursor slurry after pulping is pumped into a centrifuge for dehydration by a pneumatic diaphragm pump; the dehydrated material is washed and dehydrated for a total of 3 times, and the pH of the last washing water is ≤9.5; the washed material is dried in an oven and then ground and pulverized to obtain a ternary cathode material precursor product.

[0152] Comparative Example 4

[0153] This comparative example adopts the following steps to prepare the ternary positive electrode material precursor:

[0154] (1) The coprecipitation reaction steps are the same as those in Comparative Example 1.

[0155] (2) Aging

[0156] The ternary cathode material precursor reaction liquid obtained in step (1) is continuously overflowed into the aging kettle for aging, and N 2 protection, the nitrogen flow rate was controlled at 8 L / min, the aging temperature was 60±0.5°C, the stirring speed was 90 rpm, the aging time was 8 h, and the pH of the reaction solution was 12.8.

[0157] (3) Post-processing

[0158] The mother liquor of the ternary cathode material precursor reaction liquid after aging in step (2) is removed by a centrifuge; hot pure water at 80°C is used, and the water and the material are sequentially put into a pulping kettle for stirring and pulping according to a water: material ratio of 10:1, the pulping time is 60 minutes, and the stirring speed is 100 rpm; the precursor slurry after pulping is pumped into a centrifuge for dehydration by a pneumatic diaphragm pump; the dehydrated material is washed and dehydrated for a total of 3 times, and the pH of the last washing water is ≤9.5; the washed material is dried in an oven and then ground and pulverized to obtain a ternary cathode material precursor product.

[0159] Comparative Example 5

[0160] This comparative example adopts the following steps to prepare the ternary positive electrode material precursor:

[0161] (1) The coprecipitation reaction steps are the same as those in Comparative Example 1.

[0162] (2) Aging

[0163] The ternary cathode material precursor reaction liquid obtained in step (1) is continuously overflowed into the aging kettle for aging, and N 2 protection, the nitrogen flow rate was controlled at 8 L / min, the aging temperature was 60±0.5°C, the stirring speed was 90 rpm, the aging time was 11 h, and the pH of the reaction solution was 12.8.

[0164] (3) Post-processing

[0165] The mother liquor of the ternary cathode material precursor reaction liquid after aging in step (2) is removed by a centrifuge; hot pure water at 80°C is used, and the water and the material are sequentially put into a pulping kettle for stirring and pulping according to a water: material ratio of 10:1, the pulping time is 60 minutes, and the stirring speed is 100 rpm; the precursor slurry after pulping is pumped into a centrifuge for dehydration by a pneumatic diaphragm pump; the dehydrated material is washed and dehydrated for a total of 3 times, and the pH of the last washing water is ≤9.5; the washed material is dried in an oven and then ground and pulverized to obtain a ternary cathode material precursor product.

[0166] The particle size distribution and tap density of the ternary positive electrode material precursor products of Comparative Examples 1-5 are shown in Table 1.

[0167] Table 1: Particle size distribution and tap density of ternary cathode material precursor products of Comparative Examples 1-5

[0168]

[0169] The tap density of the ternary cathode material precursor products of Comparative Examples 1-5 is less than 1.3 g / mL, which does not meet the performance requirements of the present invention.

[0170] Example 1

[0171] In this embodiment, the following steps are used to prepare the ternary cathode material precursor:

[0172] (1) The coprecipitation reaction steps are the same as those in Comparative Example 1.

[0173] (2) Aging

[0174] The ternary cathode material precursor reaction liquid obtained in step (1) was continuously overflowed into the aging kettle for aging, and 50°C pure water was added to adjust the pH of the reaction liquid to 12.0 (50°C), and N 2 protection, the nitrogen flow rate was controlled at 8 L / min, the aging temperature was 60±0.5℃, the stirring speed was 90 rpm, and the aging time was 2 h.

[0175] (3) Post-processing

[0176] The mother liquor of the ternary cathode material precursor reaction liquid after aging in step (2) is removed by a centrifuge; hot pure water at 80°C is used, and the water and the material are sequentially put into a pulping kettle in a water: material ratio of 10:1 for stirring and pulping, the pulping time is 60 minutes, and the stirring speed is 100 rpm; the precursor slurry after pulping is pumped into a centrifuge for dehydration by a pneumatic diaphragm pump; the dehydrated material is washed and dehydrated for a total of 3 times, and the pH of the last washing water is ≤9.5; the washed material is dried in an oven and then ground and pulverized to obtain a ternary cathode material precursor product, whose SEM image is shown as follows Fig. 9 shown.

[0177] Example 2

[0178] In this embodiment, the following steps are used to prepare the ternary cathode material precursor:

[0179] (1) The coprecipitation reaction steps are the same as those in Comparative Example 1.

[0180] (2) Aging

[0181] The ternary cathode material precursor reaction liquid obtained in step (1) was continuously overflowed into the aging kettle for aging, and 50°C pure water was added to adjust the pH of the reaction liquid to 11.5 (50°C), and N 2 protection, the nitrogen flow rate was controlled at 8 L / min, the aging temperature was 60±0.5℃, the stirring speed was 90 rpm, and the aging time was 2 h.

[0182] (3) Post-processing

[0183] The mother liquor of the ternary cathode material precursor reaction liquid after aging in step (2) is removed by a centrifuge; hot pure water at 80°C is used, and the water and the material are sequentially put into a pulping kettle for stirring and pulping according to a water: material ratio of 10:1, the pulping time is 60 minutes, and the stirring speed is 100 rpm; the precursor slurry after pulping is pumped into a centrifuge for dehydration by a pneumatic diaphragm pump; the dehydrated material is washed and dehydrated for a total of 3 times, and the pH of the last washing water is ≤9.5; the washed material is dried in an oven and then ground and pulverized to obtain a ternary cathode material precursor product.

[0184] Example 3

[0185] In this embodiment, the following steps are used to prepare the ternary cathode material precursor:

[0186] (1) The coprecipitation reaction steps are the same as those in Comparative Example 1.

[0187] (2) Aging

[0188] The ternary cathode material precursor reaction liquid obtained in step (1) was continuously overflowed into the aging kettle for aging, and 50°C pure water was added to adjust the pH of the reaction liquid to 11.0 (50°C), and N 2 protection, the nitrogen flow rate was controlled at 8 L / min, the aging temperature was 60±0.5℃, the stirring speed was 90 rpm, and the aging time was 2 h.

[0189] (3) Post-processing

[0190] The mother liquor of the ternary cathode material precursor reaction liquid after aging in step (2) is removed by a centrifuge; hot pure water at 80°C is used, and the water and the material are sequentially put into a pulping kettle in a water: material ratio of 10:1 for stirring and pulping, the pulping time is 60 minutes, and the stirring speed is 100 rpm; the precursor slurry after pulping is pumped into a centrifuge for dehydration by a pneumatic diaphragm pump; the dehydrated material is washed and dehydrated for a total of 3 times, and the pH of the last washing water is ≤9.5; the washed material is dried in an oven and then ground and pulverized to obtain a ternary cathode material precursor product, whose SEM image is shown as follows Fig.10 shown.

[0191] The particle size distribution and tap density of the ternary positive electrode material precursor products of Examples 1-3 are shown in Table 2.

[0192] Table 2: Particle size distribution and tap density of the ternary cathode material precursor products of Examples 1-3

[0193]

[0194] Example 4

[0195] In this embodiment, the following steps are used to prepare the ternary cathode material precursor:

[0196] (1) The coprecipitation reaction steps are the same as those in Comparative Example 1.

[0197] (2) Aging

[0198] The ternary cathode material precursor reaction liquid obtained in step (1) was continuously overflowed into the aging kettle for aging, and the auxiliary agent ammonium sulfate was added according to the mass ratio of the reaction liquid to the auxiliary agent of 50:1, and N 2 protection, the nitrogen flow rate was controlled at 8 L / min, the aging temperature was 60±0.5℃, the stirring speed was 90 rpm, and the aging time was 2 h.

[0199] (3) Post-processing

[0200] The mother liquor of the ternary cathode material precursor reaction liquid after aging in step (2) is removed by a centrifuge; hot pure water at 80°C is used, and the water and the material are sequentially put into a pulping kettle in a water: material ratio of 10:1 for stirring and pulping, the pulping time is 60 minutes, and the stirring speed is 100 rpm; the precursor slurry after pulping is pumped into a centrifuge for dehydration by a pneumatic diaphragm pump; the dehydrated material is washed and dehydrated for a total of 3 times, and the pH of the last washing water is ≤9.5; the washed material is dried in an oven and then ground and pulverized to obtain a ternary cathode material precursor product, whose SEM image is shown as follows Fig.11 shown.

[0201] Example 5

[0202] In this embodiment, the following steps are used to prepare the ternary cathode material precursor:

[0203] (1) The coprecipitation reaction steps are the same as those in Comparative Example 1.

[0204] (2) Aging

[0205] The ternary cathode material precursor reaction liquid obtained in step (1) was continuously overflowed into the aging kettle for aging, and the auxiliary agent sodium bisulfate was added according to the mass ratio of the reaction liquid to the auxiliary agent of 50:1, and N 2 protection, the nitrogen flow rate was controlled at 8 L / min, the aging temperature was 60±0.5℃, the stirring speed was 90 rpm, and the aging time was 2 h.

[0206] (3) Post-processing

[0207] The mother liquor of the ternary cathode material precursor reaction liquid after aging in step (2) is removed by a centrifuge; hot pure water at 80°C is used, and the water and the material are sequentially put into a pulping kettle in a water: material ratio of 10:1 for stirring and pulping, the pulping time is 60 minutes, and the stirring speed is 100 rpm; the precursor slurry after pulping is pumped into a centrifuge for dehydration by a pneumatic diaphragm pump; the dehydrated material is washed and dehydrated for a total of 3 times, and the pH of the last washing water is ≤9.5; the washed material is dried in an oven and then ground and pulverized to obtain a ternary cathode material precursor product, whose SEM image is shown as follows Fig.12 shown.

[0208] The particle size distribution and tap density of the ternary positive electrode material precursor product of Example 4-5 are shown in Table 3.

[0209] Table 3: Particle size distribution and tap density of the ternary cathode material precursor products of Examples 4-5

[0210]

Claims

1. A method for preparing a ternary cathode material precursor, characterized in that: The preparation method comprises the following steps: (1) Co-precipitation reaction: a microchannel reactor is used to carry out a co-precipitation reaction to obtain a reaction solution containing a ternary cathode material precursor; (2) Aging: Aging the reaction solution obtained in step (1). Before aging, adjusting the pH value of the reaction solution to 9.5 to 12.5, or adding an auxiliary agent to the reaction solution; (3) Post-treatment: The ternary cathode material precursor aged in step (2) is post-treated, and the post-treatment includes washing, dehydration, drying and crushing.

2. The preparation method according to claim 1, characterized in that Step (2) has one or more of the following characteristics: The holding temperature during the aging process is 25 to 80°C, preferably 30 to 65°C; Before aging, adjust the pH value of the reaction solution to 9.5-12.1; Aging time is 2 to 12 hours; Nitrogen protection is carried out during the aging process, and the nitrogen flow rate is 5-10L / min; During the aging process, the reaction solution is stirred at a speed of 80 to 100 rpm.

3. The preparation method according to claim 1, characterized in that: In step (2), the auxiliary agent is selected from one or more of a surfactant, an ammonium salt and a pH regulator, and the mass ratio of the reaction solution to the auxiliary agent is (10-200):1; wherein the ammonium salt is selected from one or more of ammonium sulfate, ammonium bisulfate, ammonium carbonate, ammonium bicarbonate and ammonium dihydrogen phosphate; the pH regulator is selected from one or more of sodium bisulfate, sodium dihydrogen phosphate and aluminum chloride; preferably, the auxiliary agent is ammonium sulfate and / or sodium bisulfate.

4. The preparation method according to claim 1, characterized in that: The chemical formula of the ternary cathode material precursor is Ni x Co y M z (OH)2, wherein 0.6≤x≤0.95, 0<y≤0.2, 0<z≤0.3, x+y+z=1, and M is Al or Mn.

5. The preparation method according to claim 1, characterized in that: In step (1), the ternary cathode material precursor is generated by coprecipitation reaction of nickel salt, cobalt salt and aluminum salt or nickel salt, cobalt salt and manganese salt in the presence of a precipitant and a complexing agent in a microchannel reactor.

6. The preparation method according to claim 5, characterized in that: The microchannel reactor is a valve-type microreactor, which includes a first feed port, a second feed port, a first feed pressure regulating device, a second feed pressure regulating device, a reaction chamber and a discharge port, wherein the first feed port is connected to the reaction chamber via a first flow channel, the second feed port is connected to the reaction chamber via a second flow channel, the first feed pressure regulating device is arranged on the first flow channel between the first feed port and the reaction chamber, and is used to control the feed pressure of the first feed port, the second feed pressure regulating device is arranged on the second flow channel between the second feed port and the reaction chamber, and is used to control the feed pressure of the second feed port, the discharge port is connected to the reaction chamber, the nickel salt, cobalt salt and aluminum salt or the nickel salt, cobalt salt and manganese salt are fed to the reaction chamber via the first flow channel, and the precipitant and complexing agent are fed to the reaction chamber via the second flow channel; Preferably, the ends of the first flow channel and the second flow channel are provided with a plurality of micropores and / or slits distributed in an annular shape, so that the jets ejected from the ends of the first flow channel and the second flow channel correspond one to one, and real-time collision and mixing occur.

7. The preparation method according to claim 1, characterized in that: Step (3) comprises the following steps: (3-1) Dehydration: removing the mother liquor from the aged material; (3-2) washing: using water at 50-80° C., preferably 60-80° C., and placing the water and the material into a beating kettle in a water:material mass ratio of (5-15):1, preferably (6-12):1, for stirring and beating. The beating time is 30-120 min, preferably 45-90 min, and the stirring speed is 50-200 rpm, preferably 60-150 rpm; (3-3) Dehydration: Dehydrating the material after pulping; (3-4) repeating the washing step (3-2) and the dehydration step (3-3), with the total number of washings being ≥ 2 times, until the pH of the washing water is ≤ 9.5; (3-5) Drying and crushing: Drying and crushing the washed and dehydrated material to obtain a ternary positive electrode material precursor.

8. A ternary positive electrode material precursor prepared by the preparation method according to any one of claims 1 to 7.

9. The ternary cathode material according to claim 8, wherein the ternary cathode material precursor has one or more of the following characteristics: The Dmin of the ternary cathode material precursor is 0.8 to 1.6 μm; The D10 of the ternary cathode material precursor is 1.8 to 3.2 μm; The D50 of the ternary cathode material precursor is 5 to 19 μm; The D90 of the ternary cathode material precursor is 20 to 60 μm; The tap density of the ternary positive electrode material precursor is 1.3-1.8 g / mL.

10. A ternary positive electrode material prepared from the ternary positive electrode material precursor according to claim 8 or 9.

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