Method for controlling atmosphere of reaction vessel, method for precipitating particles and system for controlling atmosphere of reaction vessel

Abstract

A method for controlling the atmosphere of a sealable reaction vessel (60) for precipitating particles comprising one or more of Ni, Co and Mn, the method comprising: feeding in the reaction vessel (60) a gas mixture comprising oxygen and an inert gas present in a ratio; obtaining an off-gas from the reaction vessel (60), wherein the oxygen content of the gas mixture (C1) is different from the oxygen content of the off-gas (C2); measuring the oxygen content of the exhaust gas (C2) and providing the measured oxygen content as first input data (MV1); and adjusting the ratio between the oxygen and the inert gas of the gas mixture based on the first input data (MV1). A method for precipitating particles including one or more of Ni, Co, and Mn within a sealable reaction vessel. A system for controlling the atmosphere of a sealable reaction vessel (60) for precipitating particles including one or more of Ni, Co, and Mn.

Description

Technical Field

[0001] This application relates to a method for controlling the atmosphere within a sealable reaction vessel for precipitating particles. This application also relates to a method for precipitating particles comprising one or more of Ni, Co, and Mn within a sealable reaction vessel. This application further relates to a system for controlling the atmosphere within a sealable reaction vessel for precipitating particles comprising one or more of Ni, Co, and Mn. Background Technology

[0002] In methods involving the precipitation of particles in a reaction vessel, it is necessary to control conditions such as reaction conditions and the atmosphere of the reaction vessel, which exists in the space between the reaction vessel lid and the liquid surface inside the reaction vessel. Such processes may involve the precipitation of inorganic elements and / or salts, such as one or more of nickel, cobalt, and manganese. Examples of precipitated inorganic elements (reaction products) include transition metal hydroxides, oxides, or hydroxyoxides, which are produced via a co-precipitation pathway from a mixture of metal salt solution and alkaline solution. Transition metal hydroxides, oxides, or hydroxyoxides can be used as precursors for the manufacture of cathode active materials for lithium-ion batteries.

[0003] Typically, reaction conditions are controlled by adjusting, for example, the pH value or by controlling the agitation of the mixture during precipitation. Depending on the type of reaction, in some cases, the reactor atmosphere is kept inert, for example, to avoid oxidation. The reactor atmosphere can be nitrogen-protected, for example, by continuously feeding a stream of N2 gas into a sealable reaction vessel while simultaneously venting exhaust gases from the reaction vessel. In some other cases, air is fed to the reactor / reaction vessel instead of an inert gas, for example when the materials in the reactor are non-oxidizable or nearly non-oxidizable.

[0004] However, in practical industrial applications, uncontrollable variables exist, such as air leakage into the reactor / reaction vessel, causing oxygen or other gases to dissolve into the reaction mixture, making the actual reaction conditions often not exactly correspond to the predetermined reaction conditions. Therefore, there is a need to further improve the control of reaction conditions, especially the atmosphere in the reaction vessel, which exists in the space between the reaction vessel lid and the liquid surface inside the reaction vessel. Summary of the Invention

[0005] A method has been discovered to more accurately control reaction conditions and the reaction vessel atmosphere by adjusting the ratio of gases fed to the reaction vessel, particularly by feeding a specific amount of oxygen to the reaction vessel based on the oxygen content measured in the exhaust gas. Using the method and related apparatus of this invention, it is possible to control key reaction conditions, such as reaction vessel atmosphere pressure and oxygen content, and even the properties of reaction products, such as the surface area of ​​precipitated inorganic elements and impurity levels, where impurities may originate from reagents. There is no need to control or monitor challenging or uncontrollable variables, such as gases dissolved in the reaction solution. The method and apparatus of this invention overcome the disadvantages of existing methods.

[0006] In a first aspect, this disclosure provides a method for controlling the atmosphere of a hermetically sealable reaction vessel for precipitating particles comprising one or more of Ni, Co, and Mn, the method comprising:

[0007] A gas mixture comprising oxygen and an inert gas present in a certain ratio is fed into the reaction vessel; Exhaust gas is obtained from the reaction vessel, wherein the oxygen content of the gas mixture is different from the oxygen content of the exhaust gas; Measure the oxygen content of the exhaust gas and provide the measured oxygen content as first input data; and The ratio of oxygen to inert gas in the gas mixture is adjusted based on the first input data.

[0008] In a second aspect, this disclosure also provides a method for precipitating particles comprising one or more of Ni, Co, and Mn within a sealable reaction vessel, the method comprising: The desired oxygen content of the exhaust gas is obtained from the reaction vessel by controlling the atmosphere of the reaction vessel according to the method of the first aspect; and particles are prepared by co-precipitation in a contact solution within the reaction vessel, the contact solution comprising at least two dissimilar materials, one of which comprises at least one of Ni, Co and Mn.

[0009] In a third aspect, this disclosure also provides a system for controlling the atmosphere of a hermetically sealable reaction vessel for precipitating particles comprising one or more of Ni, Co, and Mn, said system comprising: A gas feeding component for supplying a gas mixture comprising oxygen and an inert gas present in a certain ratio within the reaction vessel; A gas venting component for venting waste gas from the reaction vessel; A detector is arranged to measure the oxygen content of the exhaust gas and provide the measured oxygen content as first input data; A control component is arranged to adjust the ratio between the oxygen and the inert gas in the gas mixture based on the first input data, for example, wherein the control component is arranged to perform the method according to this disclosure. Preferably, the gas feeding member includes a first feeding member for feeding a first gas including oxygen and a second feeding member for feeding a second gas including an inert gas, wherein the control member includes at least one of a first control member and a second control member, wherein the first control member is arranged to control the flow rate of the first gas based on the first input data, and the second control member is arranged to control the flow rate of the second gas based on the first input data.

[0010] The main embodiments are characterized in the independent claims. Various embodiments are disclosed in the dependent claims. Unless otherwise expressly stated, the embodiments and examples described in the claims and specification can be freely combined with each other.

[0011] The method of this invention makes it possible to eliminate the effects caused by leakage of the reaction vessel and / or unknown effects from the reaction caused by leakage.

[0012] It is also possible to control and obtain a real-time atmosphere in the reaction vessel, the atmosphere being present in the space between the reaction vessel lid and the liquid surface inside the reaction vessel.

[0013] Furthermore, the O2 concentration can be controlled during the precipitation process. This allows for control over, for example, the microstructure of the precipitated particles.

[0014] The methods and systems of this invention are scalable and can be implemented on an industrial and commercial scale. Attached Figure Description

[0015] Figure 1 An example of a setup demonstrating the reaction vessel and gas feed components is shown.

[0016] Figure 2 An example of a setup demonstrating the reaction vessel and gas venting components is shown.

[0017] Figure 3 Examples of setups including reaction vessels, gas feed components, and gas venting components are shown.

[0018] Figure 4 The system used in Example 1 is shown in Example 5 over a nine-hour period, with the valve opening of the first control component (expressed as a percentage, as shown in the figure). The scale is indicated on the right, the measured value (indicated by % and represented by □ in the figure), and the set value of O2. Detailed Implementation

[0019] In this specification, if any numerical range is provided, then the range also includes an upper limit and a lower limit. The open term "comprising" also includes the closed term "consisting of" as an option.

[0020] It has been found that precipitation in a completely inert gas atmosphere, such as in N2 or Ar, or in an all-air atmosphere, is insufficient. Instead, precipitation needs to occur within the "sweet spot" operating window and at a specific O2 concentration level in the reaction vessel atmosphere.

[0021] In particular, it was found that the atmosphere of the reaction vessel plays a crucial role in the precipitation process and affects product quality. If the amount of oxygen in the atmosphere of the precipitation reaction vessel can be controlled more precisely, the level of impurities generated by the reaction solution can be adjusted (e.g., reduced), and / or the surface area of ​​the precipitated particles can be adjusted. When the O2 content is stable, the product impurity level also stabilizes. This allows for better control of the process compared to existing systems, which do not rely on oxygen measurement-based control but instead control the process via product analysis or by monitoring the content or properties of the reaction solution in the reactor.

[0022] A method for controlling the atmosphere of a reaction vessel (e.g., a sealable or hermetically sealed reaction vessel) is disclosed, or a system including said reaction vessel (e.g., Figures 1 to 3 (As shown in the examples), the reaction vessel is used to precipitate particles comprising one or more inorganic elements, such as containing at least one of Ni, Co, and Mn, i.e., one or more. The reaction vessel and a system including the reaction vessel are also disclosed. The method, along with related apparatus and systems, can be implemented on an industrial scale and / or automated. Right now Electronic control.

[0023] "Controlled atmosphere" can refer to any suitable control action designed to control one or more properties and / or the composition of the atmosphere within a reaction vessel, and / or to control one or more reactions in which atmospheric conditions play a role in the reaction taking place within the reaction vessel. In one instance, controlled atmosphere refers to controlling the atmospheric pressure, such as the atmospheric pressure in a precipitation reactor / reaction vessel and / or another reactor / reaction vessel or container within the system. In another instance, controlled atmosphere refers to adjusting the type and quantity of gas fed into the reactor / reaction vessel.

[0024] The method can be implemented as a method for controlling the gas supply during the process and / or in the reaction vessel and / or system, a method for controlling impurity levels during the precipitation of inorganic salts in a precipitation reaction vessel, a method for controlling the atmosphere pressure during the process and / or in the (precipitation) reaction vessel, and / or a method for adjusting the surface area of ​​the precipitated inorganic salts in the precipitation reaction vessel, wherein the precipitation reaction vessel may be or include a sealable reaction vessel 60 for precipitating particles including one or more of Ni, Co, and Mn. The term "surface area" as disclosed herein refers to the area per unit mass of sample (m²). 2 Specific surface area is expressed as / g. As those skilled in the art will appreciate, specific surface area can be measured, for example, by the Brunauer-Emmett-Teller (BET) method and / or by using a surface area analyzer, such as the Quantachrome Monosorb™ analyzer.

[0025] The reactor is the core of the actual process. A reaction vessel or reactor container is a containment vessel that houses the reactor and may include other components such as temperature control elements, mixing elements, sensors, and other devices and / or parts. The reactor can define a reactor space or volume or a reaction space or volume, configured to receive reaction solutions, reagents, and gases delivered to the reactor. During the process, the reactor space or volume or reaction space or volume contains the reaction solution / dispersion and the reaction atmosphere. The reactor or reactor space may have a total volume and an effective volume smaller than the total volume.

[0026] The reaction vessel 60 may include or be any suitable reactor, vessel, container, tank, or combination thereof. The reaction vessel is designed and / or configured for the precipitation of particles, such as inorganic particles. The reaction vessel may be part of a system that includes additional devices and / or sections. The system may be an automated system, and the system may be controlled by or programmed to be controlled by one or more control elements (e.g., one or more control units). In some applications, precipitation occurs under slight pressure, and to prevent gas leakage from the workshop side, the reactor must be a sealable reaction vessel, meaning it can be operated in a sealed manner and / or opened and closed. Right nowTo obtain an airtight and / or hermetically sealed reaction vessel. Even in a sealed reaction vessel, minor leaks can occur under pressure because the reaction vessel may contain multiple inlets and outlets, as well as optionally sealable openings that are prone to leakage. However, using the method of the present invention, the effects of such leaks can be minimized or eliminated. The reaction vessel may have inlets for the substances disclosed herein, such as inlets for gases, liquids, and / or solids, such as inlets for inorganic substances and other reagents, and outlets for gases, liquids, and / or solids, such as outlets for exhaust gases, reaction products, condensates, etc. The reaction vessel may also include orifices for devices such as sensors, mixers, etc. For example, the reaction vessel may be equipped with baffles, one or more turbine blades, and / or concentrators. Right now (Mother liquor filtration device), the mother liquor can be extracted from the reaction vessel through the concentrator.

[0027] The precipitation of particles can include the crystallization and / or precipitation of one or more inorganic substances, such as one or more of Ni, Co, and / or Mn, or one or more elements comprising at least one of Ni, Co, and Mn, preferably transition metal hydroxides, oxides, or hydroxyoxides as cathode active materials. Other reagents may be included, such as dopants, one or more precipitation chemicals (e.g., NaOH), and / or one or more complexing agents. For example, in precipitation, such so-called precursor materials for cathode active materials can be obtained. The principle of precipitating precursor materials for cathode active materials in ion batteries (e.g., lithium-ion batteries) is well known in the art. Alkaline solutions (e.g., NaOH) and metal salt solutions (e.g., metal sulfate solutions) are typically used as reagents, preferably in aqueous solutions such as ammonia (NH4+). 3(aq) In the presence of a complexing agent, a dispersion can be obtained, for example, during and / or after the precipitation of the material. Therefore, the reaction solution discussed herein can also refer to a dispersion.

[0028] In one example, the method is used for precipitating inorganic precursor particles, such as precursor materials for batteries, such as NMC hydroxide. The battery may be a lithium-ion battery. In particular, the cathode material is crucial to the properties of lithium-ion batteries, and therefore it is desirable to control the formation of such cathode materials and / or their precursors. The system or apparatus setup of the present invention may be a system or setup in the battery industry, such as a system or setup in a battery material manufacturing plant. Therefore, the method of the present invention may be a method in the battery industry, or a method implemented in the battery industry.

[0029] For example, lithium-containing mixed oxides of nickel, manganese, and cobalt can be prepared in a two-stage process. In the first stage, the slightly soluble salt, such as a carbonate or hydroxide, is prepared by precipitating a slightly soluble salt of one or more transition metals from solution. This slightly soluble compound may be referred to as a precursor. In the second stage, the precursor is mixed with a lithium compound, such as Li₂CO₃, LiOH, or Li₂O, and calcined at a high temperature, for example, between 600°C and 1100°C. In an example, in the precursor manufacturing process, when carried out by (co)precipitation, sulfates of transition metals such as nickel, cobalt, and manganese are used as starting materials.

[0030] The precursor materials disclosed herein have a composition that can be represented by the general formula: MO X (OH) 2-X , where 0 ≤ x ≤ 2, and M contains at least one of Ni, Co and Mn and possibly at least one other element, such as impurities, such as Na, S, etc.

[0031] In one instance, nickel, cobalt, and manganese precipitate as a complex hydroxide, oxide, or hydroxyl oxide. Following precipitation, the particles may be washed, dried, sieved, and / or packaged.

[0032] The reaction vessel or system is equipped with at least one gas feeding component, such as a gas mixture feeding component, which may include an N2 feed circuit containing a mass flow meter and a control valve, and an air feed circuit containing a mass flow meter and a control valve. The reaction vessel or system may also be equipped with at least two gas feeding components, wherein, for example, one gas feeding component may include an N2 feed circuit containing a mass flow meter and a control valve, and the other gas feeding component may include an air feed circuit containing a mass flow meter and a control valve, and the at least two gas feeding components together provide a gas mixture comprising oxygen and an inert gas.

[0033] The method may include: A gas mixture is fed into reaction vessel 60, the gas mixture comprising components in a ratio R The presence of a first gas (e.g., oxygen or a gas containing oxygen) and a second gas (e.g., an inert gas); Waste gas is obtained from reaction vessel 60, preferably wherein the oxygen content of gas mixture C1 is different from the oxygen content of waste gas C2; Measure the oxygen content of exhaust gas C2 and provide the measured oxygen content as the first input data MV1; and The ratio R between oxygen and inert gas in the gas mixture is adjusted based on the first input data MV1.

[0034] The gas mixture may include at least a first gas and a second gas, and providing the mixture includes feeding the first gas via a first feed member 22 and the second gas via a second feed member 32, wherein the first gas includes a greater volume of oxygen than the second gas (e.g., by volume percentage). The first feed member 22 may include and / or be connected to a first line 23. The second feed member 32 may include and / or be connected to a second line 33. The first feed member 22 and the second feed member 32 may include other components, such as one or more or all portions of corresponding control members 24, 26, for example valves 21, 25, and preferably include associated actuators 21A, 25A.

[0035] The first gas can be air, including air, or derived from air, which can refer to the atmosphere or atmospheric gases, typically containing about 21% oxygen (in molar fractions). Air can be obtained by collecting and / or compressing ambient air (e.g.) into a container that can act as a first gas source from which air can be controllably supplied (e.g., fed) to the process of the present invention. The first gas may have a controlled oxygen content different from ambient air, for example, higher, such as an oxygen content in the range of 20% to 50% oxygen molar fraction.

[0036] Preferably, the second gas is an oxygen-free gas, which is substantially free of oxygen or contains only a small amount of oxygen. The term "oxygen-free gas" can refer to a gas containing 1.0 parts per million (ppm) or less of oxygen, preferably 0.1 ppm or less. The oxygen-free gas can be maintained at a purity of 99.998% by volume. The oxygen-free gas can be oxygen-free nitrogen (OFN). When using OFN, the rate of change of the existing atmosphere (O2) content can be increased. If the second gas contains some O2, the desired result, i.e., the O2 content, can be achieved. When the second gas is oxygen-free, the mixing of the gases is rapid, but if the second gas will contain O2, the adjustment of the gas mixture will take longer.

[0037] The second gas can be an inert gas. The inert gas can be any suitable inert gas or mixture thereof, such as nitrogen (N2) and / or one or more inert gases, such as argon. Gaseous nitrogen has unique properties that make it suitable for inert industrial processes. While both argon and nitrogen can achieve similar levels of inertness, their chemical properties differ, which affects the applications in which they are used. As used in this disclosure, “inert” does not mean avoiding the danger of combustion, but rather avoiding oxidation reactions in the reaction vessel and / or controlling the level of oxidation that occurs.

[0038] Argon is a denser gas than nitrogen, and therefore industrial applications using argon purging are more effective at preventing the ingress of moisture and oxygen. Its molecules are less easily dispersed than nitrogen molecules. However, producing an argon inert atmosphere is more expensive than using nitrogen due to the higher cost of argon synthesis.

[0039] The second gas may be provided from a second gas source, which may include a container for the gas and / or a gas generator, and one or more gases may be fed from the container into the process.

[0040] Gas can be supplied to the reaction vessel via gas feed member 10 for use in providing gas within the reaction vessel 60 in a ratio. R A gas mixture of oxygen and inert gas is present. The gas feeding component may include one or more components for controlling the feeding and / or delivery of the gas, such as valves, actuators, and / or the like, connected to a gas source (e.g., connected to one or more gas sources). The gas feeding component may be operatively controlled by a control component, and / or may be controlled to feed gas to a target at a desired time and / or similar manner, in a desired quantity, at a desired flow rate, at a desired ratio, and / or in a mixture of two or more gases, to achieve, for example, a desired gas feeding and / or result.

[0041] In one embodiment, the gas feeding member 10 includes a first feeding member 22 for feeding a first gas including oxygen and a second feeding member 32 for feeding a second gas including an inert gas, wherein the control member includes at least one of a first control member 24 and a second control member 26, wherein the first control member is arranged to control the flow rate of the first gas based on first input data MV1, and the second control member is arranged to control the flow rate of the second gas based on the first input data MV1.

[0042] The first feed member 22 may include a first flow measurement member arranged to measure the flow rate of a first gas passing through the first feed member 22 and provide the measured flow rate as second input data MV2 to a first control member 24, wherein the first control member 24 includes a first cascade control of a main loop using the first input data MV1 and a slave loop using the second input data MV2, and / or The second gas feed member 32 may include a second flow measurement member, which is arranged to measure the flow rate of the second gas passing through the second feed member 32 and provide the measured flow rate as third input data MV3 to the second control member 26, wherein the second control member 26 includes a second cascade control that uses first input data MV1 to control the main loop and uses the third input data MV3 to control the slave loop.

[0043] Flow measurement and / or control components may include mass flow meters 24C and 26C, such as Coriolis flow and density meters, tube mass flow meters, or heat flow meters.

[0044] The first feeding member 22 may include a first pipeline 23 having a first end 23A arranged to be connected to a first gas source and a second end 23B arranged to be connected to a reaction vessel 60, wherein a first control member 24 is located between the first end 23A and the second end 23B of the first pipeline 23; and / or The second feed member 32 may include a second line 33 having a first end 33A arranged to be connected to a second gas source and a second end 33B arranged to be connected to a reaction vessel 60, wherein a second control member 26 is located between the first end 33A and the second end 33B of the second line 33. The second ends 23B, 33B of the first line 23 and the second line 33 may be connected to another line connected to the reaction vessel 60.

[0045] "Gain" may include converting a gas within the reaction vessel into an exhaust gas, wherein the gas within the reaction vessel includes a mixture of the gas fed into the reaction vessel, the gas generated within the reaction vessel, and any gas that may leak into the reaction vessel from the outside atmosphere. The conversion may be caused by a reaction taking place within the reaction vessel. The exhaust gas may be vented from the reaction vessel 60 via a gas venting member 40.

[0046] The gas venting member 40 may include a cooling member, which may include a heat exchanger 41 arranged to cool exhaust gases discharged through the gas venting member 40 outside the reaction vessel 60. Measurements are improved when the exhaust gases are cooled before measurement. The gas venting member 40 may include a third pipeline 42.

[0047] Gases discharged from the reaction vessel Right now The exhaust gas can be cooled and condensed from moisture and / or NH3 using a cooling component, such as a cooler. A heat exchanger 41 may be connected to a portion of a gas venting component 40 located between the reaction vessel 60 and the detector 50. In one example, the method includes separating the condensate from the cooled exhaust gas and preferably recovering the separated condensate, for example, where the condensate comprises water and / or NH3. Removal of impurities, such as NH3, and optionally further cooling, facilitates the analysis of O2.

[0048] The method may include, preferably, cooling the exhaust gas via a heat exchanger 41 before measuring the oxygen content. The condensate portion of the exhaust gas may be guided back to the reaction vessel 60.

[0049] The oxygen content can be measured and / or determined using any suitable device and / or method, for example by detector 50, and more specifically by means such as Figure 1 and3 The O2% detector shown is described above. Detector 50 can also be referred to as an analyzer. The detector is advantageously arranged to continuously measure oxygen content. Right now Oxygen concentration or percentage.

[0050] Methods for determining the atmosphere, such as the O2 content in exhaust gases, include, for example, gas chromatography and thermal conductivity, preferably using corresponding devices. In an example, the oxygen content can be measured / determined by detector 50, which can be an oxygen analyzer, such as an in-situ gas analyzer, a diode laser spectrophotometer, a zirconia oxygen analyzer, an integrated oxygen analyzer, and / or a paramagnetic oxygen analyzer.

[0051] The oxygen content of gas mixture C1 differs from that of waste gas C2, indicating that the reaction occurs in a reaction vessel, which affects the oxygen content and / or alters the composition of the gas mixture and generates waste gas.

[0052] The method may include real-time control of the feeding of a mixture of inert gas and air as feedback to the measured O2 percentage of the cooling exhaust gas, to maintain the O2 percentage in the reaction vessel atmosphere gas within a predetermined (target) range, in order to control the reaction vessel atmosphere and / or other desired parameters and / or characteristics.

[0053] Adjusting the ratio of oxygen to inert gas in the gas mixture based on the first input data MV1 can be performed by a suitable control component, which can be arranged to adjust the ratio of oxygen to inert gas in the gas mixture based on the first input data MV1. This can be done automatically, preferably in real time, and the control component can be included in and / or controlled by a control unit operatively connected to the gas feed component 10 for supplying gas within the reaction vessel 60, including the ratio of oxygen to inert gas. R A mixture of oxygen and an inert gas. The ratio can be a range.

[0054] The system may include a ratio control circuit for controlling the ratio. When using the ratio control circuit, a target value or range is provided to the O2 analyzer. The opening of the control valve changes, and the target value or range of the valve can be determined based on the mass measurement of the gas. This can be done for a first gas feed or line, a second gas feed or line, or both. If the target atmosphere is inert or substantially inert, the second gas feed can be operated constantly, and the first gas feed can be adjusted. If the target atmosphere is a normal atmosphere or ambient atmosphere, the first gas feed can be operated constantly, and the second gas feed can be adjusted.

[0055] Control and control circuitry can be implemented with or without a mass meter for measuring the gas. When using a mass flow meter, control and / or adjustment are faster and more accurate. Setups may include a tubular mass flow meter, which achieves better accuracy in measurement and control / adjustment. This is because the flow rate provided by the control valve is not linear relative to the percentage of opening. When using a mass flow meter, especially a tubular mass flow meter, controllability is more stable, and control based on flow information is linear.

[0056] Adjustment ratio R It may include at least one of the following: - The flow rate of the first gas through the first feeding member 22 is controlled based on the first input data MV1; - The flow rate of the second gas through the second feeding member 32 is controlled based on the first input data MV1; - The flow rates of the first gas and the second gas through the first feeding member 22 and the second feeding member 32 are controlled based on the first input data MV1.

[0057] Control may include adjusting one or more of the flow rates to obtain a desired control action, which may include one or more of the effects disclosed herein, such as a desired ratio, content, and / or pressure of the reaction vessel atmosphere, a desired impurity level, a desired surface area for precipitating inorganic salts, and / or similar effects. Control or adjustment based on the first input data MV1 may include performing one or more control actions as feedback to the first input data MV1.

[0058] The system can be configured to perform one or more of the adjustment or control actions disclosed herein to maintain one or more parameters within a predetermined range. The actions can be performed automatically, for example, by a control unit and / or by one or more control elements.

[0059] The oxygen content can be controlled, for example, by controlling the flow rate of the first gas only, (2) controlling the flow rate of the second gas only, or (3) controlling both the flow rates of the first gas and the second gas.

[0060] In one example, after the cooler (heat exchanger), detector 50 (e.g., an online O2% analyzer, which may be supplied with a sample gas cleaning scrubber) measures the O2 content of the exhaust gas. The O2 content of the atmosphere of the gas mixture fed into the reaction vessel is known and can be affected by changing the ratio of the first and second gases. This is possible by the operating system directly providing the O2% value as a setpoint, and then the operating system adjusts the gas mixture feed.

[0061] Adjustment ratio R It may include: - Set the first oxygen setting value SV1 for the exhaust gas; - Receive the first input data MV1; - Determine the first difference between the first oxygen setpoint SV1 and the first input data MV1, SV1-MV1; and a) Increase the flow rate of the first gas when the first difference SV1-MV1 is positive, and / or decrease the flow rate of the first gas when the difference SV1-MV1 is negative, and / or b) Decrease the flow rate of the second gas when the first difference SV1-MV1 is positive, and / or increase the flow rate of the second gas when the first difference SV1-MV1 is negative.

[0062] The method may include: -Measure the flow rate of the first gas through the first feed member 22; - Provide the measured flow rate of the first gas as the second input data MV2; and - The flow rate of the first gas is controlled by a first-stage cascade control system, which includes a main loop and a slave loop. -The first input data MV1 is used to control the main loop, and the second input data MV2 is used to control the slave loop.

[0063] Cascading control is a control method and also refers to the corresponding control components, which may include cascading connections and / or cascading circuits. Cascading control combines the output of two or more controllers / feedback loops with the output of one controller (the primary controller) to adjust the setpoint of a second controller (the auxiliary controller). The controller that drives the setpoint is called the primary controller, external controller, or master controller. The controller that receives the setpoint (the flow controller in this example) is called the auxiliary controller, internal controller, or slave controller. Correspondingly, the main loop can be called the primary loop or external loop, and the slave loop can be called the auxiliary loop or internal loop.

[0064] Cascading is an arrangement of two or more components or circuits such that the output of one component or circuit is the input of the next. Cascading involves several control variables and one adjustable variable, thus adjusting the actual variable via another variable. Adjustment is accelerated by using an auxiliary controller that responds more quickly to control changes, in addition to the main controller. Cascading circuits include nested control loops. Through cascading control, it is possible to accurately control the flow in the system.

[0065] The method may include: -Measure the flow rate of the second gas through the second feed member 32; - Provides the measured flow rate of the second gas as the third input data MV3; and - The flow rate of the second gas is controlled by a second-stage cascade control system, which includes a main loop and a slave loop. -The first input data MV1 is used to control the main loop of the second cascade control, and the third input data MV3 is used to control the slave loop of the second cascade control.

[0066] Obtaining waste gas may involve discharging waste gas from the reaction vessel 60 through a gas venting member 40, said venting including: - Waste gas is drawn out by a vacuum source 49, which can be connected to the reaction vessel 60 via a third pipeline 42; - Measure the pressure within the third pipeline 42 and provide the determined pressure as the fourth input data MV4; and - The flow rate of exhaust gas through the third pipeline 42 is controlled based on the fourth input data MV4. The vacuum source 49 may be connected to the reaction vessel via an intermediate container and / or components for controlling the vacuum (e.g., via an expansion container 43). The vacuum source 49 may include a vacuum container and / or components for providing a vacuum, such as a vacuum pump, or an exhaust fan 48.

[0067] Controlling the flow rate of the exhaust gas through the third pipeline 42 may include: - Pressure setting value for receiving exhaust gas SV3; - Determine the third difference between the pressure setpoint SV3 and the fourth input data MV4, SV3-MV4; and - When the third difference SV3-MV4 is positive, the exhaust gas flow rate is increased, and when the third difference SV3-MV4 is negative, the exhaust gas flow rate is decreased.

[0068] The method may include converting a portion of the exhaust gas into a liquid and a gaseous form by cooling the exhaust gas, and guiding the liquid and gaseous portions separately, optionally wherein the liquid portion is guided back to the reaction vessel 60. Approximately 90% of the exhaust gas may have already been liquefied in the cooler.

[0069] One example provides a method for precipitating particles within a sealable reaction vessel, the particles comprising one or more elements including at least one of Ni, Co, and Mn, the method comprising: - Obtain the required oxygen content from the exhaust gas in reaction vessel 60 by controlling the atmosphere of the reaction vessel; and - Particles are prepared or generated by co-precipitation in a contact solution within a reaction vessel 60, the contact solution comprising at least two dissimilar materials, including one or more elements comprising at least one of Ni, Co, and Mn. In one example, the method for precipitating particles includes or comprises a method for preparing an aqueous Me(OH)2 slurry, wherein Me refers to one or more transition metals.

[0070] The preparation of particles by co-precipitation may include supplying and mixing a first aqueous solution comprising one or more metal salts selected from Ni, Co, and Mn, and a second aqueous solution comprising a precipitant / precipitation agent in a reaction vessel. The precipitant may comprise one or more hydroxides selected from carbonates and bicarbonates. Preferably, the precipitant is a hydroxide, such as NaOH.

[0071] The method may further include supplying and mixing a third aqueous solution comprising a complexing agent in a reaction vessel 60. Preferably, the complexing agent is an ammonia-based complexing agent. The complexing agent may include or be based on an organic acid, such as one or more selected from glycine, tartrate, citrate, and oxalate.

[0072] Figure 3 Examples of systems for controlling the atmosphere of a sealable reaction vessel 60 for precipitating particles comprising one or more of Ni, Co, and Mn are disclosed. Figure 1 and 2 A portion of an exemplary system is disclosed. The system may include: Gas feeding member 10, which is used to provide a gas mixture comprising oxygen and an inert gas present in a ratio R within the reaction vessel 60; Gas venting component 40, which is used to vent waste gas from reaction vessel 60; Detector 50 is arranged to measure the oxygen content of the exhaust gas and provide the measured oxygen content as the first input data MV1; A control component is arranged to adjust the ratio of oxygen to inert gas in the gas mixture based on first input data MV1. The control component may be arranged to perform the method or a portion thereof.

[0073] The control component may include at least one of the first control component 24 and the second control component 26.

[0074] The first control member 24 is arranged to control the flow rate of the first gas arranged to flow through the first feed member 22, wherein the detector 50 is arranged to provide first input data MV1 to the first control member 24, and wherein the first control member 24 is arranged to control the flow rate of the first gas based on the first input data MV1.

[0075] The first control component 24 may include a valve 21 and a processing component for controlling the valve opening, such as a controllable actuator 21A, and / or a flow transmitter (FT) 24A and a flow indicator and controller (FIC) 24B. The second control component 26 may include a valve 25 and a processing component for controlling the valve opening, such as a controllable actuator 25A, and / or a flow transmitter (FT) 26A and a flow indicator and controller (FIC) 26B. The flow transmitters 24A and 26A are arranged to transmit measured flow measurement data to corresponding controllers 24B and 26B, and the controllers are arranged to receive the data and control the corresponding valves 21 and 25, preferably by operating the corresponding controllable actuators 21A and 25A as feedback to the received data.

[0076] The system may include a second control member 26 for controlling the flow rate of a second gas arranged to flow through a second feed member 32, wherein a detector 50 is arranged to provide first input data MV1 to the second control member 26, and wherein the second control member 26 is arranged to control the flow rate of the second gas based on the first input data MV1. This provides alternative and / or additional means for controlling the gas supply. Right now The concentration of O2 gas within the reaction vessel is controlled. The first control element 24 and the second control element 26 may include mass flow meters 24C and 26C for measuring gas flow rates. Detector 50 may be arranged to provide data to the first controller 24B and the second controller 26B. The control elements or controllers control actuators 21A and 25A of valves 21 and 25 to actuate the valves. This affects the flow rate of the first gas and / or the second gas.

[0077] The measured values ​​are real values ​​(typically excluding zero). However, when the difference is 0, the flow rate remains unaffected. Right now The measured value matches the set value perfectly.

[0078] In one embodiment, the gas feeding component includes a first feeding component 22 for feeding a first gas including oxygen and a second feeding component 32 for feeding a second gas including an inert gas, wherein the control component includes at least one of a first control component 24 and a second control component 26, wherein the first control component 24 is arranged to control the flow rate of the first gas based on first input data MV1, and the second control component 26 is arranged to control the flow rate of the second gas based on the first input data MV1. As used herein, a control component may refer to one or more control components, which may be independent and / or arranged to be independently controlled, and / or may be under the control of another control component (e.g., a higher-level and / or master control component, system, or unit). The master control component, system, or unit may be connected to other control components, e.g., operatively connected, and / or may be arranged to monitor other control components. The master control component, system, or unit may be arranged to control the entire setup.

[0079] The first control component 24 can be arranged as follows: - Receive the first oxygen setpoint SV1; - Determine the first difference between the first oxygen setpoint SV1 and the first input data MV1, SV1-MV1; and - When the first difference SV1-MV1 is positive, the flow rate of the first gas is increased, and when the first difference SV1-MV1 is negative, the flow rate of the first gas is decreased, and preferably the flow rate is maintained when the first difference is zero.

[0080] The second control component 26 can be arranged as follows: - Receive the second oxygen setting value SV2; - Determine the oxygen setpoint (the second difference between V2 and the first input data MV1, SV2-MV1); and - When the second difference SV2-MV1 is positive, the flow rate of the second gas is reduced, and when the second difference SV2-MV1 is negative, the flow rate of the second gas is increased, and preferably the flow rate is maintained when the second difference is zero.

[0081] Figure 3 An embodiment is shown in which the second ends 23B and 33B of the first pipeline 23 and the second pipeline 33 are combined and then connected to the reaction vessel 60.

[0082] The gas venting component 40 may include a third line 42 having a first end 42A arranged to be connected to the reaction vessel 60 and a second end 42B arranged to be connected to a vacuum source 49. -The venting component 40 further includes a third control component 44 and a second detector 46, such as a pressure gauge. -The second detector 46 is arranged to measure the pressure within the third pipeline 42 and provides the measured pressure as fourth input data MV4 to the third control member 44; and -The third control element 44 is arranged to control the flow rate of the exhaust gas through the third pipeline 42 based on the fourth input data MV4.

[0083] The third control component 44 can be arranged as follows: -Receive pressure setpoint SV3; - Determine the third difference between the pressure setpoint (SV3) and the fourth input data (MV4), (SV3-MV4); and - When the third difference (SV3-MV4) is positive, the exhaust gas flow rate is increased, and when the third difference (SV3-MV4) is negative, the exhaust gas flow rate is decreased.

[0084] The third control element 44 may include a valve and processing elements for controlling the opening of the valve, such as a controllable actuator and / or a flow transmitter (FT), as well as a flow indicator and controller, and / or similar elements. The second detector 46 may be arranged to measure the pressure within the third line 42 via an intermediate container (e.g., expansion container 43), and / or to measure the pressure within the container.

[0085] Exhaust gas pipeline ( Right now The pressure inside the third pipeline is the settling pressure (the pressure in the reaction vessel). Therefore, the reactor pressure can be controlled by controlling the pressure inside the exhaust gas pipeline.

[0086] The system may include an expansion container or expansion tank 43, which provides additional volume for exhaust gases within the venting member and thus acts as a buffer to provide adjustability. The expansion container 43 may be controlled, for example, by operating one or more valves at one or more inlets and / or one or more outlets.

[0087] The venting component 40 may include an expansion vessel 43, preferably including an outlet 47, which is used to separate the condensate portion within the pipeline and guide it separately from the gaseous portion outside the third pipeline 42. The expansion vessel 43 may be a pressure-reducing vessel, which may be used and / or arranged to adjust the pressure in the reaction vessel 60 to a predetermined (target) range. An outlet (e.g., a gas outlet) from the expansion vessel 43 may be (controllably) connected to a low-pressure exhaust fan 48, which helps control the pressure in the expansion vessel 43 and in the system. Pressure reduction in the reaction vessel 60 has an impact on precipitation reactions and, for example, the evaporation of ammonia; therefore, providing an expansion vessel 43 in the system helps control the conditions in the reaction vessel and / or the reaction conditions.

[0088] In one example, the exhaust outlet is connected to a scrubber, and the system includes an exhaust pressure control circuit preceding the scrubber. The exhaust pressure control circuit, including a cooling component, can be connected to the exhaust outlet and can be arranged to separate condensed NH3 and water, and to deliver the exhaust gas to a pressure-reducing tank to adjust the pressure to a predetermined range.

[0089] The system may include pressure control or equalization circuitry arranged to adjust the pressure to a predetermined range. This involves an expansion container, a washer, and its controls, such as one or more controllable valves controlled by a control element. This enables the negative pressure generated by the washer to be reduced to a desired level. The expansion container 43 may include an outlet 47 for a condensation section at the bottom. The expansion container 43 may include a pressure gauge for measuring the pressure within the container 43, wherein the measured / determined pressure value can be used to control the pressure within the container by controlling one or more control valves connected to the container, such that the pressure within the expansion container 43 can be maintained within a target pressure range.

[0090] With a pressure-controlled circuit, less NH3 evaporates, and precipitation can occur at the desired pressure. If a leak exists in the reaction vessel, its impact (e.g., leakage of ambient air into the reaction vessel) is lower because less vacuum exists within the vessel. Furthermore, with a pressure-controlled circuit, the precipitation reaction can be influenced by controlling the depressurization and exhaust gas scrubbing within the reaction vessel. This has no direct impact on oxygen measurements, and the pressure within the reaction vessel can be maintained within the desired range should the amount of gas fed to it change. It is possible to synchronize different reactions occurring in the system and control gas mixtures and pressures, resulting in better control, especially on industrial and commercial scales.

[0091] The system may include one or more control components, which may include one or more control units and / or be operatively connected to one or more control units and / or other components, such as those disclosed herein. The control components are electronic and may include one or more processors and memory, as well as user interfaces, displays, keyboards, touchscreens and / or other input components, power connections, network connections (which may be wired and / or wireless), and / or connections to each of the controllable components of the system disclosed herein. The control components may include one or more computers and / or integrated and / or embedded systems. The control components may include software arranged to perform one or more control actions when running with the processor to perform one or more control actions to perform the methods of the present invention or portions thereof, and optionally perform one or more other methods, generally performing system operation. Since system components (including any actuators, valves, relays, motors, pumps, heating components, cooling components, sensors, cameras, etc.) that may need to be monitored and operated are electronically and / or operatively connected to the control unit, the control unit may be arranged (including being programmed) to operate these components. By controlling the components, it is possible to obtain and / or maintain the desired operation of the system. Control components may be connected to, and / or may include one or more other components, such as actuators, valves, actuators arranged to control valves, flow transmitters, flow indicators, and controllers, and / or similar and / or other components. For example, in the case of a first control component, a second control component, and a third control component, it may be further connected to other control components, such as a main control component, and / or it may operate independently. Generally, multiple (e.g., two or more) separate control components in a system may be referred to as "control components".

[0092] The system and / or control components may be arranged to perform the methods disclosed herein, and / or one or more portions and / or operations of the methods. The desired portions or operations may include, for example, obtaining and / or maintaining desired (predetermined) values, such as target values, more precisely, a range of target values, for example, by providing one or more control actions that affect variables such as gas flow rate, gas ratio, temperature, flow rate, rotational speed, liquid or suspension level, pH, substance concentration, etc., to maintain variables within a target range, and / or input and / or output substances, such as liquids, solids, and / or gases.

[0093] This disclosure provides a system for performing one or more of the methods disclosed herein.

[0094] Example The invention will be further illustrated below with reference to some examples and comparative examples.

[0095] Measurement methods used in the example A) Na and SO4 analysis The Na and SO4 contents of the obtained cathode active material precursor powder were measured using inductively coupled plasma-optical emission spectrometry (ICP-OES) on a Thermo iCAP 6000 series ICP-OES instrument. The measurement samples were prepared as follows: 0.25 g of powder sample from each example and comparative example was dissolved in deionized (DI) water in a 100 ml volumetric flask. The volumetric flask was filled to the 100 ml mark with DI water and then completely homogenized. 1 ml of solution was pipetted and transferred to a 100 ml volumetric flask for a second dilution. A suitable amount of concentrated nitric acid was added via pipette to obtain a 5% HNO3 solution upon reconstitution with deionized (DI) water, followed by homogenization. Finally, this solution was used for ICP-OES measurement. The SO4 content is expressed as %, and the Na content is expressed as g / t.

[0096] B) Surface area analysis The specific surface area (SA) of the example samples was measured using the Brunol-Emmett-Taylor (BET) method with Quantachrome Monosorb. Prior to measurement, the powdered sample was placed in a sample tube and heated at 90°C for 2 hours under nitrogen (N2) to remove adsorbed substances. The sample was then degassed at room temperature for five minutes. Nitrogen adsorption was tested at 77 K. The total specific surface area (in m² / g) of the sample was obtained by acquiring nitrogen isotherm adsorption / desorption curves.

[0097] C) Particle size distribution (PSD) analysis After dispersing the sample particles in an aqueous medium, the PSD of the secondary particles was measured using a Malvern Mastersizer 3000 with a Hydro MV wet dispersion unit. To improve the dispersion of the metal hydroxide powder, sufficient ultrasonic irradiation and stirring were applied, and a suitable surfactant was introduced. Average particle size. D10, D50, and D90 are the particle diameter values ​​at 10%, 50%, and 90% of the cumulative distribution, respectively, and the span value is (D90-D10) / D50.

[0098] Example 1 according to Figure 1 , 2 The system of 3 is constructed to include a sealable reaction vessel 60 having a total volume of 250 I and an effective volume of 200 I, the sealable reaction vessel being equipped with baffles and a six-bladed turbine for mixing, and a concentrator for extracting mother liquor from the reaction vessel. Right now Mother liquor filtration device.

[0099] The system includes: a gas feeding member 10 for supplying gas within the reaction vessel 60 at a ratio of R A gas mixture containing oxygen and an inert gas is present; a gas venting member 40 is used to vent exhaust gas from the reaction vessel 60; an O2 percentage analyzer 50 is arranged to measure the oxygen content of the exhaust gas and provide the measured oxygen content as first input data MV1 to control members 24, 26; and a control member is arranged to adjust the ratio between oxygen and inert gas in the gas mixture based on the first input data (MV1). R (as described above in this instruction manual).

[0100] The gas feeding member 10 includes a first feeding member 22 for feeding a first gas including oxygen and a second feeding member 32 for feeding a second gas including an inert gas, and the control member includes a first control member 24 arranged to control the flow rate of the first gas and a second control member 26 arranged to control the flow rate of the second gas, both based on the first input data MV1.

[0101] The first control component 24 includes a valve 21 and a controllable actuator 21A for controlling the valve opening, a flow transmitter (FT) 24A, and a flow indicator and controller (FIC) 24B. The second control component 26 includes a valve 25 and a controllable actuator 25A for controlling the valve opening, a flow transmitter (FT) 26A, and a flow indicator and controller (FIC) 26B. Both the first control component 24 and the second control component 26 include pipe mass flow meters 24C and 26C.

[0102] The oxygen content (C2) of the exhaust gas from the reaction vessel is measured by using a system setup that includes a 3-way valve, precooler, cooler 41, filter, sample pump, and rotor flow meter after the reaction vessel 60, and then the gas is delivered to the O2 percentage analyzer 50 based on the paramagnetic alternating pressure measurement principle.

[0103] The output from analyzer 50 serves as the first input data (MV1) to the control unit, used to adjust the ratio between the gas mixtures fed into the reactor vessel. The control unit is programmed to adjust the gas feed as feedback to the first input data (MV1) to obtain the desired gas flow rate and ratio. The first gas, comprising oxygen, is air, and the second gas, comprising an inert gas, is nitrogen. Experiments have demonstrated that, under the control settings of this invention, the atmosphere and / or oxygen content within the reaction vessel can be effectively and in real-time controlled, thus affecting the levels of products and impurities formed.

[0104] The gas venting component used is equipped with a multi-stage wet gas scrubber to vent exhaust gas from the reaction vessel and to generate negative pressure in the gas venting component and the reaction vessel.

[0105] Example 2 The setup is similar to that used in Example 1. However, the oxygen content (C2) of the exhaust gas from the reaction vessel is measured using a zirconium dioxide cell analyzer 50.

[0106] Similar results and observations as in Example 1 can also be obtained through this system setting.

[0107] Example 3 150 m³ of water was added to a sealable reaction vessel having a total volume of 250 I and an effective volume of 200 I. 3 Water was added and heated to 85°C. The sealable reaction vessel was equipped with baffles and a six-bladed turbine, and a concentrator through which the mother liquor could be drawn from the reaction vessel. Then, 1.25 kg of 220 g / L ammonia water and 24 L of seed slurry containing 120 g / L Ni(OH)₂ particles with a D50 of 1.5 μm were added, and the pH of the resulting starting solution was adjusted to 11.4 (measured at 20°C) with 230 g / L NaOH (aqueous solution). Nitrogen was supplied through the vessel at 250 L / h and air at 25 L / h, respectively, to obtain and maintain an atmosphere with an O₂ content of 2.0% by volume within the reaction vessel. The pressure within the reaction vessel was maintained at -24.6 mbar, while the pressure within the gas venting structure (exhaust gas pressure) was maintained at -30.0 mbar.

[0108] Next, although the reaction solution was maintained at 85°C and 11 kW / m 3 The reactor was stirred at a power density, but continuously fed with 120 g / L of a metal sulfate solution comprising Ni, Mn, and Co (in a stoichiometric molar ratio of Ni:Mn:Co = 90:5:5), 220 g / L of ammonia, and 230 g / L of NaOH solution. The feed rate of the metal sulfate solution was 11 l / h for the first two hours, and then 25 l / h for the remainder of the precipitation process. The feed rates of ammonia and NaOH were maintained so that the pH (measured at 20°C) and ammonium ion concentration were controlled to pH 11.2 to 11.6 and 3 to 4 g / L, respectively. The process was stopped when the D50 of the reactor sample reached the target value of approximately 5.0 μm.

[0109] The obtained slurry was filtered and alkali-washed, followed by a drying step to obtain the cathode active material precursor, i.e., the precursor material. The physicochemical analysis of the obtained cathode active material precursor was performed as described below, including measurements of D50 particle size, surface area, and Na and SO4 impurity levels, and the results are given in Table 1.

[0110] Comparative Example 1 The cathode active material precursor was prepared and analyzed according to the same procedure described in Example 3, except that the atmosphere inside the reaction vessel was kept completely inert by supplying nitrogen only at 250 l / h.

[0111] Example 4 160 I of water was added to a sealable reaction vessel with a total volume of 250 I and an effective volume of 200 I, and heated to 65 °C. The sealable reaction vessel was equipped with baffles, a six-bladed turbine, and a concentrator through which the mother liquor could be drawn from the reaction vessel. Then, 6 kg of 220 g / L ammonia solution was added, and the pH of the resulting initial solution was adjusted to 12.4 (measured at 20 °C) with 230 g / L NaOH (aqueous solution). Nitrogen was supplied through the vessel at 175 L / h and air at 22.5 L / h, respectively, to obtain and maintain an atmosphere with an O2 content of 2.5% by volume within the reaction vessel. The pressure within the reaction vessel was maintained at -24.6 mbar, while the pressure within the gas venting structure (exhaust gas pressure) was maintained at -30.0 mbar.

[0112] Next, although the reaction solution was maintained at 65°C and 3 kW / m 3 The reactor was stirred at a power density, but continuously fed with 120 g / L of a metal sulfate solution comprising Ni, Mn, and Co (in a stoichiometric molar ratio of Ni:Mn:Co = 65:20:15), 220 g / L of ammonia, and 230 g / L of NaOH solution. The feed rate of the metal sulfate solution was 12 l / h for the first two hours, and then 25 l / h for the remainder of the precipitation process. The feed rates of ammonia and NaOH were maintained so that the pH (measured at 20°C) and ammonium ion concentration were controlled to pH 11.2 to 11.9 and 7 to 10 g / L, respectively. The process was stopped when the D50 of the reactor sample reached the target value of approximately 10.0 μm.

[0113] The obtained slurry was filtered and alkali-washed, followed by a drying step to obtain the cathode active material precursor. Physicochemical analysis of the obtained cathode active material precursor was performed as described below, including measurements of D50 particle size, surface area, and Na and SO4 impurity levels, and the results are given in Table 1.

[0114] Comparative Example 2 The cathode active material precursor was prepared and analyzed according to the same procedure described in Example 4, except that the atmosphere inside the reaction vessel was kept completely inert by supplying nitrogen only at 175 l / h.

[0115] Table 1. Physicochemical analysis results of Examples 3 to 4 and Comparative Examples 1 to 2

[0116] Example 5 The atmosphere in reaction vessel 60 is controlled using a system as described in Example 1. Oxygen is introduced into the reaction vessel atmosphere via a first feed member (22), while nitrogen is supplied via a second feed member. The setpoint for the oxygen content in the atmosphere is set to 3.0 volume % (SV1), which is the volume of oxygen relative to the total volume of gas in the atmosphere. Nitrogen feeding begins at 250 L / h, and air feeding via the first feed member begins at 100 L / h. The oxygen content, defined as the ratio of oxygen to inert gas (R), is then adjusted based on the measured oxygen content (C2) as described in Example 1 and used as the first input data (MV1). This adjustment is achieved by controlling the opening of a valve in the first control member of the first feed member, which changes the airflow and thus the oxygen content in the atmosphere.

[0117] Figure 4 Showing the valve opening degree of the first control component (expressed as a percentage, as shown in the figure) over a nine-hour period. The graph shows the measured value (indicated by a % scale on the right side of the graph, represented by a □ on the left side of the graph) and the set value of O2. As illustrated, the measured value closely follows the set value when the valve opening is continuously adjusted.

Claims

1. A method for controlling the atmosphere of a sealable reaction vessel (60) for precipitating particles comprising one or more of Ni, Co, and Mn, the method comprising: By feeding a first gas via a first feeding member (22) and a second gas via a second feeding member (32) into the reaction vessel (60), a mixture comprising gas at a ratio of ( R A gas mixture (Cl) containing oxygen and an inert gas, wherein the first gas comprises a greater volume of oxygen than the second gas; Exhaust gas is obtained from the reaction vessel (60), wherein the oxygen content of the gas mixture (C1) is different from the oxygen content of the exhaust gas (C2); Measure the oxygen content of the exhaust gas (C2) and provide the measured oxygen content as first input data (MV1); and By controlling the flow rate of the first gas or the flow rate of the second gas, or both, the ratio between the oxygen and the inert gas in the gas mixture is adjusted based on the first input data (MV1). R ).

2. The method according to claim 1, wherein the second gas is an oxygen-free gas.

3. The method according to claim 2, wherein the adjustment of the ratio ( R It contains at least one of the following: - Control the flow rate of the first gas through the first feeding member (22) based on the first input data (MV1); - The flow rate of the second gas through the second feeding member (32) is controlled based on the first input data (MV1); - The flow rates of the first gas and the second gas through the first feed member (22) and the second feed member (32) are controlled based on the first input data (MV1).

4. The method according to any one of claims 1 to 3, wherein the method comprises preferably cooling the exhaust gas via a heat exchanger (41) before measuring the oxygen content, and optionally guiding a condensate portion of the exhaust gas back to the reaction vessel (60).

5. The method according to any one of claims 1 to 4, wherein the adjustment of the ratio ( R )include: Set the first oxygen setpoint (SV1) for the exhaust gas. Receive the first input data (MV1); Determine the first difference between the first oxygen setpoint (SV1) and the first input data (MV1), (SV1-MV1); and a) When the first difference (SV1-MV1) is positive, increase the flow rate of the first gas; and when the difference (SV1-MV1) is negative, decrease the flow rate of the first gas. b) When the first difference (SV1-MV1) is positive, reduce the flow rate of the second gas, and when the first difference (SV1-MV1) is negative, increase the flow rate of the second gas.

6. The method according to any one of claims 2 to 5, wherein the method comprises: Measure the flow rate of the first gas passing through the first feeding member (22); Provide the measured flow rate of the first gas as the second input data (MV2); and The flow rate of the first gas is controlled by a first-stage cascade control system, which includes a main loop and a slave loop. The first input data (MV1) is used to control the main loop, and the second input data (MV2) is used to control the slave loop.

7. The method according to any one of claims 2 to 6, wherein the method comprises: Measure the flow rate of the second gas through the second feeding member (32); The measured flow rate of the second gas is provided as the third input data (MV3); and The control that adjusts the flow rate of the second gas via a second cascade control, the second cascade control comprising a main loop and a slave loop, The first input data (MV1) is used to control the main loop of the second cascaded control, and the third input data (MV3) is used to control the slave loop of the second cascaded control.

8. The method according to any one of claims 1 to 7, wherein obtaining the waste gas comprises discharging the waste gas from the reaction vessel (60) through a gas venting member (40), the discharging comprising: The exhaust gas is drawn in by a vacuum source (49) connected to the reaction vessel (60) via a third pipeline (42); Measure the pressure in the third pipeline (42) and provide the determined pressure as the fourth input data (MV4); as well as The flow rate of the exhaust gas through the third pipeline (42) is controlled based on the fourth input data (MV4).

9. The method of claim 8, wherein controlling the flow rate of the exhaust gas through the third pipeline (42) comprises: Receive the pressure setpoint (SV3) of the exhaust gas; Determine the third difference between the pressure setpoint (SV3) and the fourth input data (MV4), (SV3-MV4); and When the third difference (SV3-MV4) is positive, the flow rate of the exhaust gas is increased, and when the third difference (SV3-MV4) is negative, the flow rate of the exhaust gas is decreased.

10. The method according to any one of claims 1 to 9, wherein the method comprises converting a portion of the waste gas into a liquid portion and a gaseous portion by cooling the waste gas, and guiding the liquid portion separately from the gaseous portion, optionally wherein the liquid portion is guided back to the reaction vessel (60).

11. A method for precipitating particles comprising one or more of Ni, Co, and Mn within a sealable reaction vessel, the method comprising: The desired oxygen content of the exhaust gas is obtained from the reaction vessel (60) by controlling the atmosphere of the reaction vessel according to any one of claims 0 to 0; as well as The particles are prepared by co-precipitation in a contact solution within the reaction vessel (60), the contact solution comprising at least two dissimilar materials, one of which comprises one or more of Ni, Co, and Mn.

12. The method of claim 11, wherein the preparation of particles by co-precipitation comprises supplying and mixing in the reaction vessel a first aqueous solution comprising one or more metal salts of Ni, Co and Mn and a second aqueous solution comprising a precipitant.

13. The method of claim 12, wherein the precipitant comprises a hydroxide or at least one selected from carbonates and bicarbonates, preferably wherein the precipitant is a hydroxide.

14. The method according to any one of claims 11 to 13, wherein the method further comprises supplying and mixing a third aqueous solution comprising a complexing agent in the reaction vessel (60), preferably wherein the complexing agent is an ammonia-based complexing agent.

15. A system for controlling the atmosphere of a sealable reaction vessel (60) for precipitating particles comprising one or more of Ni, Co, and Mn, said system comprising: Gas feeding member (10), which is used to provide gas within the reaction vessel (60) at a ratio of ( R A mixture of oxygen and inert gases; A gas venting component (40) is used to vent waste gas from the reaction vessel (60); A detector (50) is arranged to measure the oxygen content of the exhaust gas and provide the measured oxygen content as first input data (MV1). A control component is arranged to adjust the ratio between the oxygen and the inert gas in the gas mixture based on the first input data (MV1). R For example, the control element is arranged to perform the method according to any one of the preceding claims. The gas feeding member (10) includes a first feeding member (22) for feeding a first gas including oxygen and a second feeding member (32) for feeding a second gas including an inert gas. The control member includes at least one of a first control member (24) and a second control member (26). The first control member is arranged to control the flow rate of the first gas based on the first input data (MV1), and the second control member is arranged to control the flow rate of the second gas based on the first input data (MV1).

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