Preparation device and preparation method for positive electrode material of alkali metal ion battery

Abstract

The present application discloses a device for preparing positive electrode materials for alkali metal ion batteries, comprising a shell, a reaction component, a heating unit and a circulation component. The shell has an inner cavity, a feed port and a discharge port. The reaction component is arranged in the inner cavity to vertically divide the inner cavity into an upper cavity and a lower cavity. The upper cavity is connected to the feed port, and the lower cavity is connected to the discharge port. The reaction component has a receiving cavity and a liquid inlet and a liquid drain hole connected to the receiving cavity. The receiving cavity is used to receive precursor materials. The liquid inlet is connected to the upper cavity, and the liquid drain hole is connected to the lower cavity. The precursor material is placed in the receiving cavity, the heating unit heats the material in the receiving cavity, and the reaction liquid is added. The reaction liquid enters the receiving cavity through the liquid inlet, contacts and reacts with the precursor. The positive electrode material of the battery is generated by the replacement reaction. The reaction temperature is lower than that of the solid phase method, the reaction time is also shorter, and the energy consumption cost is low. The present application also discloses a method for preparing positive electrode materials for alkali metal ion batteries.

Description

Technical Field

[0001] The present application belongs to the technical field of battery positive electrode material preparation, and specifically relates to a preparation device and method for alkali metal ion battery positive electrode material. Background Art

[0002] In recent years, the new energy sector has experienced rapid growth. Batteries, as highly efficient energy conversion and storage devices, are widely used in electric vehicles, portable electronic devices, and energy storage power stations. With the rapid development of electric vehicles, demands for higher range and higher energy density in lithium-ion batteries are increasing. Consequently, the cathode materials used in automotive lithium-ion batteries are trending towards ternary batteries. Ternary cathode materials, due to their high energy density and low cost, have become a research hotspot.

[0003] Traditionally, ternary cathode materials are prepared using a solid-phase method, in which the raw materials are mixed and reacted in a solid phase before being sintered at high temperatures. However, this method requires high sintering temperatures, long reaction times, and high energy costs. Furthermore, the resulting materials exhibit significant variations in structure and particle size distribution, resulting in poor performance. Summary of the Invention

[0004] The technical problem to be solved by this application is that the traditional solid-phase method for preparing positive electrode materials has high energy consumption cost and poor performance of the synthesized materials. In order to solve the above technical problems, a preparation device and method for positive electrode materials for alkali metal ion batteries with low energy consumption cost and good performance of the synthesized materials are provided.

[0005] The technical solutions proposed in this application are:

[0006] A device for preparing positive electrode materials for alkali metal ion batteries, comprising:

[0007] A shell having an inner cavity and a feed port and a discharge port connected to the inner cavity, wherein the feed port is located at the top of the shell for allowing the reaction liquid to enter, and the discharge port is located at the bottom of the shell;

[0008] a reaction assembly disposed in the inner cavity to vertically divide the inner cavity into an upper cavity and a lower cavity, wherein the upper cavity is communicated with the feed port, and the lower cavity is communicated with the discharge port; the reaction assembly comprises a receiving cavity and a liquid inlet and a liquid drain hole communicated with the receiving cavity; the receiving cavity is used to receive a precursor material, the liquid inlet is communicated with the upper cavity, and the liquid drain hole is communicated with the lower cavity;

[0009] a heating unit, disposed in the reaction assembly, for heating the material in the accommodating cavity; and

[0010] A circulation component, wherein both ends of the circulation component are respectively connected to the feed port and the discharge port, so that the reaction liquid circulates in the inner cavity and the circulation component.

[0011] Furthermore, the reaction assembly includes a partition, a top plate and a baffle structure, the partition is connected to the inner wall of the inner cavity, the top plate and the partition are arranged at intervals in the vertical direction and are located above the partition, the baffle structure is connected to the top plate and the partition to enclose the top plate and the partition to form the accommodating cavity, the top plate is provided with the liquid inlet, and the partition is provided with the drainage hole;

[0012] The reaction component includes a push plate and a discharge valve. The push plate and the discharge valve are respectively located at two ends of the accommodating cavity. The push plate is configured to be controllably moved close to and away from the discharge valve.

[0013] Furthermore, the preparation device further comprises a central rod, which extends vertically in the inner cavity and passes through both ends of the shell;

[0014] The partition has a first end and a second end relative to each other, the first end and the second end are respectively connected to the center rod and the inner wall of the inner cavity, the first end and the second end have different heights, and the feed port corresponds to the higher one of the first end and the second end, and the drainage hole is located at the other one.

[0015] Furthermore, the preparation device comprises a plurality of groups of reaction components, and the plurality of groups of reaction components are arranged at intervals along the vertical direction;

[0016] The preparation device also includes a plurality of guide tubes, one end of each guide tube is connected to the side of the corresponding partition away from the feed port and is connected to the drainage hole, and the other end corresponds to the higher one of the first end and the second end of the partition below.

[0017] Furthermore, the circulation component includes a circulation pump, a liquid storage tank and a pH detector. The liquid storage tank is used to store the reaction liquid. The circulation pump is connected to the discharge port and the liquid storage tank. The liquid outlet of the liquid storage tank is connected to the feed port. The pH detector is arranged in the liquid storage tank.

[0018] Furthermore, the shell is further provided with an air inlet connected to the inner cavity, and the preparation device further comprises an air supply mechanism, which is connected to the air inlet.

[0019] A method for preparing a positive electrode material for an alkali metal ion battery comprises the following steps:

[0020] S110, placing the precursor material in the receiving chamber;

[0021] S120, adding an AOH aqueous solution into the inner cavity through the feed port, wherein A is one of Li, Na, and K, and heating the AOH aqueous solution to react with the precursor material, or the AOH aqueous solution reacts with the oxidizing gas and the precursor material to obtain a reaction product. The reaction liquid is discharged from the discharge port into the circulation component and refluxed to the feed port under the action of the circulation component;

[0022] S130, after the reaction is completed, the reaction products are sequentially eluted to obtain a positive electrode material.

[0023] Furthermore, the precursor material is Ni x Co y Mn 1-x-y (OH)2、Ni x Co y Mn 1-x-y OOH、NixCoyAl 1-x-y (OH)2、Ni x Co y Al 1-x-y OOH、NaNi x Co y Mn 1-x-y O2, KNi x Co y Mn 1-x-y O2, FePO4, Fe 1-x Mn x One or more of PO4, NaFePO4.

[0024] Furthermore, the preparation method further comprises the steps of:

[0025] The AOH aqueous solution in the circulation component is subjected to pH detection or material composition analysis to detect the alkali metal ion concentration in the AOH aqueous solution, and an alkali metal source is added to the required concentration according to the alkali metal ion concentration.

[0026] Furthermore, the concentration of alkali metal ions in the AOH aqueous solution is 0.1-4 mol / L.

[0027] Furthermore, the reaction temperature is 50-95°C.

[0028] Furthermore, the oxidizing gas is any one of oxygen and air.

[0029] Using the above-mentioned device for preparing positive electrode materials for alkali metal ion batteries, the precursor material is first placed in a receiving chamber. The material in the receiving chamber is then heated by a heating unit. Subsequently, a reaction liquid is added to the inner chamber through the feed port. The reaction liquid enters the receiving chamber through the liquid inlet, contacts and reacts with the precursor, thereby generating a replacement reaction to form the positive electrode material. The battery positive electrode material generated by the replacement reaction has a lower reaction temperature and a shorter reaction time than the solid-phase method, resulting in lower energy consumption costs. At the same time, the battery positive electrode material generated by the replacement reaction has better performance.

[0030] In addition, the reaction liquid flows into the lower cavity through the drainage hole and is discharged through the liquid outlet, and can then flow back to the feed port through the circulation component. The replacement reaction process does not require the introduction of other impurity elements. The reaction liquid will lose some ion concentration after the reaction. At this time, the ion concentration can be restored by adding the corresponding alkali metal salt, and the reaction continues under the action of the circulation component. There is no need to treat the reaction liquid after the reaction as waste liquid, which further improves the utilization rate of the alkali metal and reduces the material cost and processing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are used to provide further understanding of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application.

[0032] Figure 1 A schematic structural diagram of a device for preparing positive electrode materials for alkali metal ion batteries according to one embodiment of the present application;

[0033] Figure 2 for Figure 1 A schematic structural diagram of the reaction components in the preparation device shown;

[0034] Figure 3 A schematic flow chart of a method for preparing a positive electrode material for an alkali metal ion battery provided in another embodiment of the present application;

[0035] Figure 4 is the XRD pattern of the precursor material and the reaction product prepared in Example 1;

[0036] Figure 5 The charge and discharge performance of the battery assembled from the reaction product prepared in Example 1.

[0037] Description of labels:

[0038] 100. Preparation device; 200. Precursor material; 110. Shell; 111. Inner cavity; 112. Feed port; 113. Discharge port; 114. Observation port; 120. Reaction component; 121. Partition; 1211. Drain hole; 1212. First end; 1213. Second end; 122. Top plate; 123. Push plate; 124. Discharge valve; 125. Drive member; 126. Heating unit; 130. Circulation component; 131. Liquid storage tank; 132. Circulation pump; 140. Bracket; 150. Center rod; 160. Guide tube; 170. Inlet pipe. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0040] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on this application.

[0041] In order to facilitate understanding of the technical solution of this application, the preparation principle and application of this application are explained here:

[0042] H + / Li + / Na + / K + Ion exchange method is a new method developed in recent years to synthesize positive electrode materials for alkali metal ion batteries. It has the advantages of low reaction temperature and easy to obtain high-performance low-temperature metastable phases that are difficult to generate at high temperatures. For example, Li + / Na + The ion exchange method is to use LiNi x Co y Mn 1-x-y O2 has a similar structure to NaNi x Co y Mn 1-x-y O2 acts as a precursor and undergoes ion exchange reaction with lithium-containing reagents to achieve Li +and Na + exchange, and then synthesize LiNi x Co y Mn 1-x-y O2 material. Li + / H + The ion exchange method uses Ni x Co y Mn 1-x-y OOH is used as a precursor to undergo ion exchange reaction with lithium-containing reagents to achieve Li + and H + exchange, and then synthesize LiNi x Co y Mn 1-x-y O2 materials. Since existing ion exchange reactions are mostly batch reactions and lack dedicated reactors, they are usually prepared on a small scale in the laboratory.

[0043] On the one hand, if Figure 1 and Figure 2 As shown, an embodiment of the present application provides a device 100 for preparing positive electrode materials for alkali metal ion batteries, including a housing 110 , a reaction component 120 , a heating unit 126 and a circulation component 130 .

[0044] The housing 110 has an inner cavity 111 and a feed port 112 and a discharge port 113 connected to the inner cavity 111. The feed port 112 is located at the top of the housing 110, and the discharge port 113 is located at the bottom of the housing 110. The feed port 112 is used to allow the reaction liquid to enter. The reaction assembly 120 is disposed in the inner cavity 111 to vertically divide the inner cavity 111 into an upper cavity and a lower cavity. The upper cavity is connected to the feed port, and the lower cavity is connected to the discharge port.

[0045] The reaction component 120 has a receiving cavity and a liquid inlet and a liquid discharge hole 1211 communicating with the receiving cavity. The liquid inlet communicates with the upper cavity, and the liquid discharge hole 1211 communicates with the lower cavity.

[0046] The heating unit 126 is provided with the reaction assembly 120 for heating the material in the accommodating chamber. The two ends of the circulation assembly 130 are respectively connected to the feed port 112 and the discharge port 113 so that the reaction liquid circulates in the inner chamber 111 and the circulation assembly 130.

[0047] It should be noted that in this embodiment, the reaction liquid is an aqueous solution of AOH (A = Li, Na, K) with a concentration of 0.1~4 mol / L; the precursor material 200 is Ni x Co y Mn 1-x-y (OH)2、Ni x Co y Mn 1-x-y OOH、Nix Co y Al 1-x-y (OH)2、Ni x Co y Al 1-x-y OOH、NaNi x Co y Mn 1-x-y O2, KNi x Co y Mn 1-x-y O2, FePO4, Fe 1-x Mn x PO4, NaFePO4, or one or more thereof, wherein 0<x<1, 0<y<1. A substitution reaction occurs between the reaction liquid and the precursor material 200 to generate a positive electrode material. The reaction liquid is a LiOH aqueous solution, and the precursor material 200 is NaNi x Co y Mn 1-x-y O2 is taken as an example, and the battery positive electrode material LiNi is generated after the reaction. x Co y Mn 1-x-y O2.

[0048] Using the above-mentioned preparation device 100 for alkali metal ion battery positive electrode materials, the precursor material 200 is first placed in the accommodating chamber, and then the material in the accommodating chamber is heated by the heating unit 126. Subsequently, the reaction liquid is added to the inner cavity 111 through the feed port 112. The reaction liquid enters the accommodating chamber through the liquid inlet, contacts and reacts with the precursor, thereby generating a replacement reaction to generate the positive electrode material. The battery positive electrode material is generated by the replacement reaction. Compared with the solid phase method, the reaction temperature is lower, the reaction time is shorter, and the energy consumption cost is low. At the same time, the battery positive electrode material generated by the replacement reaction has better performance.

[0049] In addition, the reaction liquid flows into the lower cavity through the drain hole 1211 and is discharged through the liquid outlet, and can then flow back to the feed port 112 through the circulation component 130. The replacement reaction process does not require the introduction of other impurity elements. The reaction liquid will lose some ion concentration after the reaction. At this time, the ion concentration can be restored by adding the corresponding alkali metal salt, and the reaction can continue under the action of the circulation component 130. There is no need to treat the reaction liquid after the reaction as waste liquid, which further improves the utilization rate of the alkali metal and reduces the material cost and processing cost.

[0050] It should be noted that the replacement reaction between the reaction liquid and the precursor material 200 refers to a replacement reaction between the reaction liquid and specific ions in the precursor material 200. This reaction does not introduce or generate other impurities, and therefore does not affect the structure and particle size distribution. This ensures that the resulting positive electrode material has uniform structure and particle size distribution, thereby improving the performance of the positive electrode material. In addition, the reaction temperature of the precursor material 200 and the reaction liquid is preferably 50-95°C.

[0051] In one embodiment, the preparation device 100 further includes a bracket 140 , and the housing 110 is disposed on the bracket 140 so that the housing 110 is spaced apart from the ground.

[0052] In one embodiment, the reaction assembly 120 includes a partition 121, a top plate 122, and a baffle structure. The partition 121 is connected to the inner wall of the inner cavity 111. The top plate 122 and the partition 121 are arranged vertically spaced apart, with the top plate 122 located above the partition 121. The baffle structure is connected to the top plate 122 and the partition 121 to enclose the top plate 122 and the partition 121 to form a receiving chamber for receiving the precursor material 200. The top plate 122 is provided with the aforementioned liquid inlet, and the partition 121 is provided with the aforementioned liquid drainage hole 1211.

[0053] As an example, the top plate 122 may be a mesh plate to ensure that the reaction liquid can enter the accommodating chamber through the top plate 122 and prevent the reaction liquid from docking on the reaction assembly 120. In addition, the baffle structure includes two baffles, which are arranged at intervals and are both connected to the top plate 122 and the partition plate 121, thereby enclosing and forming the accommodating chamber.

[0054] Furthermore, the reaction assembly 120 further includes a push plate 123 and a discharge valve 124. The push plate 123 and the discharge valve 124 are respectively located at two ends of the accommodating chamber, and the push plate 123 is configured to be controllably moved closer to and farther from the discharge valve 124.

[0055] After the reaction liquid enters the inner cavity 111, it can enter the receiving chamber through the liquid inlet of the top plate 122. The precursor material 200 in the receiving chamber reacts with the reaction liquid, and the reacted reaction liquid flows out from the drainage hole 1211. After the precursor material 200 has reacted completely, the reaction assembly 120 is removed from the inner cavity 111, and then the discharge valve 124 is opened and the push plate 123 is pushed to push the reaction product in the receiving chamber out through the discharge valve 124. It can be seen that the shape and size of the push plate 123 match the shape and size of the cross-section of the receiving chamber to ensure that the reaction product in the receiving chamber is pushed out.

[0056] Furthermore, the reaction assembly 120 further includes a driving member 125, which is fixed relative to the partition 121 and connected to the push plate 123 to drive the push plate 123 toward and away from the discharge valve 124. Optionally, the driving member 125 is an electric cylinder or a pneumatic cylinder, which is not limited here.

[0057] In one embodiment, the preparation device 100 further includes a central rod 150, which extends vertically in the inner cavity 111 and passes through both ends of the shell 110, and the partition 121 is connected to the central rod 150 and the inner wall of the inner cavity 111. It can be understood that the central rod 150 passes through the top and bottom of the shell 110. In addition, the central rod 150 can facilitate the arrangement of the partition 121. In other embodiments, the partition 121 can also be directly connected to the inner wall of the shell 110. Figure 1 In the illustrated embodiment, the central rod 150 is located at the center of the inner cavity 111 .

[0058] Furthermore, the reaction assembly 120 includes multiple partitions 121, which are arranged around the central rod 150, with adjacent partitions 121 interconnected. In this manner, the multiple partitions 121 can vertically separate the inner cavity 111. In other embodiments, a single partition 121 can be provided to separate the inner cavity 111, without limitation. It is also confirmed that each partition 121 is provided with the aforementioned drainage hole 1211.

[0059] It should be noted that when the reaction assembly 120 includes multiple partitions 121, the top plate 122, the baffle structure, the push plate 123, the discharge valve 124, and the driving member 125 are all multiple and are arranged in a one-to-one correspondence with the partitions 121. Each partition 121 is provided with multiple heating units 126. When the reaction assembly 120 includes a partition 121 capable of dividing the inner cavity 111, the top plate 122, the baffle structure, the push plate 123, the discharge valve 124, and the driving member 125 can also be multiple to form multiple accommodating chambers, and the multiple accommodating chambers are arranged at intervals around the central rod 150, and each accommodating chamber is correspondingly provided with multiple heating units 126.

[0060] In one embodiment, the partition plate 121 has a first end 1212 and a second end 1213 relative to each other, the first end 1212 being connected to the center rod, and the second end 1213 being connected to the inner wall of the inner cavity. The heights of the first end 1212 and the second end 1213 are different, and the feed port 112 corresponds to the higher one of the first end 1212 and the second end 1213, and the drainage hole 1211 is located at the other one. After the reaction liquid enters the inner cavity 111, it drips onto the higher end, then flows along the partition plate 121 to the lower end, and then flows from the drainage hole 1211 to the lower cavity. In this way, the reaction liquid and the precursor material 200 can be brought into contact more fully, ensuring that the precursor reaction is complete.

[0061] Preferably, the push plate 123 is positioned near the higher end of the first end 1212 or the second end 1213. Since the drainage hole 1211 is located at the other end, the push plate 123 will not stagger with the drainage hole 1211 during movement, that is, it will not affect the drainage hole 1211, ensuring that the reaction liquid can flow out through the drainage hole 1211.

[0062] Specific to Figure 1 and Figure 2 In the illustrated embodiment, the height of the first end 1212 is higher than the height of the second end 1213. The first end 1212 of each partition 121 is connected to the central rod 150, and the other end is connected to the inner wall of the inner cavity 111. Furthermore, to ensure that the reaction liquid entering the feed port 112 drips onto the first end 1212, a liquid distribution pipe can be provided in the inner cavity 111.

[0063] In one embodiment, the preparation apparatus 100 includes multiple groups of reaction assemblies 120, which are arranged at intervals along the vertical direction. It is understood that each reaction assembly 120 can vertically divide the inner cavity into an upper cavity and a lower cavity, that is, the cavity in two adjacent reaction assemblies 120 is the lower cavity of the upper reaction assembly 120 and also the upper cavity of the lower reaction assembly 120. In this way, the reaction liquid can flow through the accommodating cavities of the multiple layers of reaction assemblies 120 in sequence and react with the precursor material 200 in the accommodating cavity of each layer of reaction assemblies 120, thereby improving the preparation efficiency.

[0064] Furthermore, the preparation device 100 also includes a plurality of guide tubes 160, one end of each guide tube 160 is connected to the side of the corresponding partition 121 away from the feed port 112, and is connected to the drainage hole 1211, and the other end corresponds to the higher one of the first end 1212 and the second end 1213 of the lower partition 121, so as to ensure that the reaction liquid can fully contact the precursor material 200 on each partition 121.

[0065] It is understood that the guide tube 160 may not be provided for the partition 121 at the bottom layer. Of course, when assembling the preparation device 100, it is usually necessary to first connect the guide tube 160 to the partition 121, and then install the partition 121 and other structures into the inner cavity 111. At this time, for the convenience of processing, the guide tube 160 can also be connected to the partition 121 at the bottom layer, and this is not limited here.

[0066] In one embodiment, the housing 110 further defines an air inlet communicating with the inner cavity 111. The preparation apparatus 100 further includes a gas supply mechanism that communicates with the air inlet for supplying an oxidizing gas into the inner cavity 111 to create an oxidizing environment for the reaction between the reaction solution and the precursor material 200. The oxidizing gas may be one or more of air, oxygen, or ozone.

[0067] Furthermore, the housing 110 is provided with multiple air inlets, each of which is provided with an air inlet pipe 170. The air supply mechanism is connected to the multiple air inlet pipes 170. It should be noted that to ensure that the gas within the chamber is an oxidizing gas and to achieve oxidation of the material, the chamber above each reaction assembly 120 is provided with an air inlet pipe 170. In other embodiments, an oxidizing environment can also be created by adding an oxidant to the reaction solution.

[0068] In actual application, the housing 110 is further provided with an exhaust port, which is in communication with the inner cavity 111 and is used to discharge the gas in the inner cavity 111. In this way, the gas supply mechanism inputs oxidizing gas into the inner cavity 111, and the original gas in the inner cavity 111 is discharged from the exhaust port, thereby replacing the gas in the inner cavity 111.

[0069] In one embodiment, the housing 110 further defines an observation port 114 , which is in communication with the inner cavity 111 . A seal made of a transparent material is provided at the observation port 114 to facilitate observation of the reaction of the precursor material 200 through the observation port 114 .

[0070] In one embodiment, the circulation component 130 includes a liquid storage tank 131 and a circulation pump 132. The liquid storage tank 131 is used to store the reaction liquid, and the liquid outlet of the liquid storage tank 131 is connected to the feed port 112. The circulation pump 132 is connected to the discharge port 113 and the liquid storage tank 131, so that the reaction liquid circulates in the inner cavity 111 and the liquid storage tank 131. Furthermore, the liquid storage tank 131 is also provided with a feeding port, through which the corresponding alkali metal salt can be added to the liquid storage tank 131.

[0071] It should be noted that, in other embodiments, a circulation pump 132 may also be provided between the liquid outlet of the liquid storage tank 131 and the feed port 112 , so as to pump the reaction liquid in the liquid storage tank 131 into the inner cavity 111 .

[0072] In one embodiment, the circulation component 130 also includes a pH detector, which is arranged in the liquid storage tank 131 and is used to detect the pH value of the reaction liquid in the liquid storage tank 131, so as to judge the metal ion concentration in the reaction liquid according to the pH value. When the metal ion concentration drops to a certain value, alkali metal salt is added to the liquid storage tank 131 through the feed port until the metal ion concentration returns to the required concentration value.

[0073] In other embodiments, if a replacement reaction of alkali metal ions occurs between the reaction solution and the precursor material, a pH detector is not provided, and the reaction solution can be subjected to ICP detection to obtain the alkali metal ion concentration, and then the amount of alkali metal salt replenished can be ensured based on the concentration.

[0074] On the other hand, based on the device 100 for preparing the positive electrode material for an alkali metal ion battery in the above embodiment, the present application also provides a method for preparing the positive electrode material for an alkali metal ion battery, such as Figure 3 As shown, the preparation method comprises the steps of:

[0075] S110 , placing the precursor material 200 in the receiving chamber.

[0076] Specifically, oxidizing gas is input into the inner cavity 111 through the gas supply mechanism, and the original gas in the inner cavity 111 is discharged through the exhaust port to replace the gas in the inner cavity 111. At the same time, during the reaction process, the gas supply mechanism also continuously inputs oxidizing gas into the inner cavity 111 until the reaction is completed.

[0077] S120, add AOH aqueous solution into the inner cavity 111 through the feed port 112, where A is one of Li, Na, and K, heat, and react the AOH aqueous solution with the precursor material, or react the AOH aqueous solution with the oxidizing gas and the precursor material to obtain a reaction product. The AOH aqueous solution is discharged from the discharge port 113 into the circulation component 130, and refluxes to the feed port 112 under the action of the circulation component, so that the precursor material 200 reacts completely with the reaction liquid.

[0078] It should be explained that when the current drive material is Ni x Co y Mn 1-x-y (OH)2、Ni x Co y Al 1-x-y When (OH) 2 is present, in step S120 , an oxidizing gas needs to be introduced into the inner cavity 111 to carry out the reaction.

[0079] Specifically, if it is necessary to introduce oxidizing gas into the inner cavity 111, the oxidizing gas can be input into the inner cavity 111 through the gas supply mechanism, and the original gas in the inner cavity 111 is discharged through the exhaust port to replace the gas in the inner cavity 111. At the same time, during the reaction process, the gas supply mechanism also continuously inputs oxidizing gas into the inner cavity 111 until the reaction is completed.

[0080] Furthermore, the material in the chamber can be heated by the heating unit 126 to ensure a reaction temperature of 50-95° C. In the inner chamber 111 , the reaction liquid flows through the multiple reaction components 120 in sequence and is discharged from the discharge port 113 . It then flows back to the feed port 112 under the action of the circulation pump 132 .

[0081] During the reaction process, the AOH aqueous solution in the circulation component 130 can also be subjected to pH testing or material composition analysis testing to detect the alkali metal ion concentration in the AOH aqueous solution. Specifically, when the precursor material is an alkali metal transition metal oxide, pH testing is preferably used, and the alkali metal ion concentration can be known by detecting the hydroxide ion concentration therein; when the precursor material is a transition metal hydroxide, material composition analysis testing, such as ICP testing, is required to directly determine the alkali metal ion concentration. If the alkali metal ion concentration drops to a certain value, an alkali metal salt can be added to the liquid storage tank 131 through the feed port until the metal ion concentration returns to the initial concentration value.

[0082] S130, after the reaction is completed, the reaction products are sequentially eluted to obtain a positive electrode material.

[0083] Specifically, after elution, drying, grinding and screening operations are performed.

[0084] The device 100 for preparing positive electrode materials for alkali metal ion batteries and the method for preparing positive electrode materials for alkali metal ion batteries in the above embodiments have at least the following advantages:

[0085] 1. The positive electrode material is prepared by ion exchange reaction without introducing impurity elements, which can ensure the uniformity of the structure and particle size distribution of the positive electrode material and improve the performance of the positive electrode material;

[0086] 2. The specific reaction only needs to be heated to 50~95℃, and there is no need to react for a long time in a high temperature environment, which reduces energy consumption costs;

[0087] 3. The reaction solution can be restored to its initial concentration by adding alkali metal salts, thereby achieving repeated reactions of the reaction solution. There is no need to treat the reaction solution after the reaction, which further improves the utilization rate of the alkali metal and reduces material and treatment costs.

[0088] 4. Multiple reaction assemblies 120 are provided, and by providing a flow guide 160, the reaction liquid can fully react with the precursor material 200 in each reaction assembly 120, thereby improving the preparation efficiency of the positive electrode material;

[0089] 5. After the reaction is completed, the reaction assembly 120 is taken out, and the reaction product in the accommodating chamber can be pushed out from the discharge valve 124 through the push plate 123, making it more convenient to obtain the reaction product.

[0090] In order to facilitate understanding of the technical solution of the present application, the specific preparation process of the positive electrode material is described here with a specific embodiment:

[0091] Example 1

[0092] First, add the precursor material NaNi into the accommodating chamber.0.8 Co 0.1 Mn 0.1 O2, and then start the heating unit 126 to raise the temperature in the chamber to 90 ° C. A lithium hydroxide aqueous solution with a concentration of 4 mol / L is introduced from the feed port 112, and the lithium hydroxide aqueous solution flows through the multiple reaction components 120 in sequence and undergoes a replacement reaction with the precursor material 200 to generate LiNi 0.8 Co 0.1 Mn 0.1 O2. The lithium hydroxide aqueous solution is discharged from the discharge port and refluxed to the feed port 112 under the action of the circulation pump 132. During the reaction, the concentration of lithium hydroxide is detected. If the concentration of lithium hydroxide is lower than 2.5 mol / L, lithium hydroxide is added to the liquid storage tank 131 through the feed port. After the reaction is completed, the reaction product is removed and sequentially eluted, dried, ground, and sieved to obtain the positive electrode material.

[0093] During the reaction, the XRD patterns of the precursor material and the prepared cathode material are as follows: Figure 4 As shown in the figure, it can be seen that LiNi 0.8 Co 0.1 Mn 0.1 O2.

[0094] Prepare the positive electrode material into an oral battery according to the following method:

[0095] According to the mass ratio (active material: conductive agent: binder = 8:1:1), 0.08g of positive electrode material, 0.01g of acetylene black as a conductive agent, and 0.01g of polyvinylidene fluoride as a binder were weighed and placed in a mortar for mixing. After mixing evenly, N-methylpyrrolidone was added as a dispersant. After mixing again, the mixture was coated on aluminum foil to make a positive electrode sheet. In a glove box under an inert protective atmosphere, metallic lithium was used as the negative electrode to assemble a CR2032 button battery.

[0096] The button battery was charged and discharged at room temperature within the voltage range of 2.8 to 4.3 V. The charge and discharge performance curve is as follows: Figure 5 As shown in the figure, it can be concluded that the prepared positive electrode material has excellent electrochemical properties.

[0097] Example 2

[0098] First, add the precursor material Ni into the accommodating chamber. 0.5 Co 0.2 Mn 0.3(OH)2, and then start the heating unit 126 to raise the temperature in the chamber to 95°C. Next, oxygen is input into the inner chamber 111 through the gas supply mechanism, and the original gas in the inner chamber 111 is discharged from the exhaust port. A lithium hydroxide aqueous solution with a concentration of 4 mol / L is introduced from the feed port 112, and the lithium hydroxide aqueous solution flows through multiple groups of reaction components 120 in sequence and undergoes a replacement reaction with the precursor material 200 to generate LiNi 0.5 Co 0.2 Mn 0.3 O2. The lithium hydroxide aqueous solution is discharged from the discharge port and refluxed to the feed port 112 under the action of the circulation pump 132. The pH value of the solution is tested during the reaction. If the pH value is lower than 12, lithium hydroxide is added to the liquid storage tank 131 through the feed port. After the reaction is completed, the reaction product is removed and sequentially eluted, dried, ground, and sieved to obtain the positive electrode material.

[0099] Example 3

[0100] First, add the precursor material Ni into the accommodating chamber. 1 / 3 Co 1 / 3 Mn 1 / 3 OOH, and then start the heating unit 126 to raise the temperature in the chamber to 80°C. Next, oxygen is input into the inner chamber 111 through the gas supply mechanism, and the original gas in the inner chamber 111 is discharged from the exhaust port. A lithium hydroxide aqueous solution with a concentration of 3 mol / L is introduced from the feed port 112, and the lithium hydroxide aqueous solution flows through multiple groups of reaction components 120 in sequence and undergoes a replacement reaction with the precursor material 200 to generate LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2. The lithium hydroxide aqueous solution is discharged from the discharge port and refluxed to the feed port 112 under the action of the circulation pump 132. The pH value of the solution is tested during the reaction. If the pH value is lower than 12, lithium hydroxide is added to the liquid storage tank 131 through the feed port. After the reaction is completed, the reaction product is removed and sequentially eluted, dried, ground, and sieved to obtain the positive electrode material.

[0101] Although the embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A device for preparing positive electrode materials for alkali metal ion batteries, characterized in that: include: A shell having an inner cavity and a feed port and a discharge port connected to the inner cavity, wherein the feed port is located at the top of the shell for allowing the reaction liquid to enter, and the discharge port is located at the bottom of the shell; A plurality of reaction components are arranged in the inner cavity at intervals along the vertical direction, and each of the reaction components can divide the inner cavity into an upper cavity and a lower cavity in the vertical direction; each of the reaction components includes a partition, a top plate, a baffle structure, a push plate, a discharge valve and a driving member, the partition is connected to the inner wall of the inner cavity, the top plate and the partition are arranged at intervals along the vertical direction and are located above the partition, the baffle structure is connected to the top plate and the partition to enclose the top plate and the partition to form a accommodating cavity, the top plate is provided with a liquid inlet, the partition is provided with a drainage hole, the accommodating cavity is used to accommodate precursor materials, the liquid inlet is communicated with the corresponding upper cavity, and the drainage hole is communicated with the corresponding lower cavity; The push plate and the discharge valve are respectively located at two ends of the accommodating chamber, and the driving member is fixed relative to the partition and connected to the push plate to drive the push plate to approach and move away from the discharge valve; a central rod extending vertically within the inner cavity and passing through both ends of the shell; the partition having a first end and a second end opposite to each other, the first end and the second end being connected to the central rod and the inner wall of the inner cavity, respectively, and the first end and the second end being at different heights; a plurality of flow guide tubes, each of which has one end connected to a side of a corresponding partition away from the feed port and in communication with the drainage hole, and the other end corresponding to the higher one of the first end and the second end of the partition below; in the top reaction assembly, the feed port corresponds to the higher one of the first end and the second end, and the drainage hole is located at the other end; a heating unit, disposed in the reaction assembly, for heating the material in the accommodating cavity; and A circulation component, wherein both ends of the circulation component are respectively connected to the feed port and the discharge port, so that the reaction liquid circulates in the inner cavity and the circulation component.

2. The device for preparing positive electrode materials for alkali metal ion batteries according to claim 1, characterized in that: The circulation component includes a circulation pump, a liquid storage tank and a pH detector. The liquid storage tank is used to store the reaction liquid. The circulation pump is connected to the discharge port and the liquid storage tank. The liquid outlet of the liquid storage tank is connected to the feed port. The pH detector is arranged in the liquid storage tank.

3. The device for preparing positive electrode materials for alkali metal ion batteries according to claim 1, characterized in that: The shell is further provided with an air inlet communicated with the inner cavity, and the preparation device further comprises an air supply mechanism, which is communicated with the air inlet.

4. A method for preparing a positive electrode material for an alkali metal ion battery, characterized in that: The preparation method is carried out using the preparation device for alkali metal ion battery positive electrode materials according to any one of claims 1 to 3, and the preparation method comprises the steps of: S110, placing the precursor material in the receiving chamber; S120, adding an AOH aqueous solution into the inner cavity through the feed port, wherein A is one of Li, Na, and K, and heating the AOH aqueous solution to react with the precursor material, or the AOH aqueous solution reacts with the oxidizing gas and the precursor material to obtain a reaction product. The reaction liquid is discharged from the discharge port into the circulation component and refluxed to the feed port under the action of the circulation component; S130, after the reaction is completed, the reaction products are sequentially eluted to obtain a positive electrode material.

5. The method for preparing the positive electrode material for alkali metal ion batteries according to claim 4, characterized in that: The precursor material is Ni x Co y Mn 1-x-y (OH)2、Ni x Co y Mn 1-x-y OOH、Ni x Co y Al 1-x-y (OH)2、Ni x Co y Al 1-x-y OOH、NaNi x Co y Mn 1-x-y O2, KNi x Co y Mn 1-x-y O2, FePO4, Fe 1-x Mn x One or more of PO4, NaFePO4; wherein, 0<x<1, 0<y<1.

6. The method for preparing the positive electrode material for alkali metal ion batteries according to claim 4, characterized in that: The preparation method further comprises the steps of: The AOH aqueous solution in the circulation component is subjected to pH detection or material composition analysis to detect the alkali metal ion concentration in the AOH aqueous solution, and an alkali metal source is added to the required concentration according to the alkali metal ion concentration.

7. The method for preparing the positive electrode material for alkali metal ion batteries according to claim 4, characterized in that: The concentration of alkali metal ions in the AOH aqueous solution is 0.1~4mol / L; The reaction temperature is 50-95°C; The oxidizing gas is any one of oxygen and air.

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