WO2024011940A1 - Lithium battery homogenizing apparatus and homogenizing method thereof - Google Patents

Abstract

A lithium battery homogenizing apparatus, which is used for the homogenization of lithium battery materials. The lithium battery homogenizing apparatus comprises an apparatus body (1), wherein a control system (2) is arranged on the apparatus body (1), a homogenizer (3) is arranged in the apparatus body (1), and a powder tank assembly (4) and a liquid tank assembly (5) are arranged outside the apparatus body (1); and the powder tank assembly (4) and the liquid tank assembly (5) are respectively connected to the homogenizer (3), and the control system (2) is respectively connected to the homogenizer (3), the powder tank assembly (4) and the liquid tank assembly (5). Further provided is a homogenizing method of a lithium battery homogenizing apparatus. The present invention can improve the homogenizing effect and efficiency, the production efficiency and the adaptability to homogenate viscosity, and can mix a slurry more uniformly.

Description

A kind of lithium battery homogenization equipment and its homogenization method Technical field

The invention relates to the technical field of homogenization, and in particular to a lithium battery homogenization equipment and a homogenization method thereof.

Background technique

With the widespread application of consumer electronics and new energy vehicles, lithium-ion batteries have become one of the research hotspots. The preparation of slurry is a key process in the production of lithium-ion batteries. The performance of electrode slurries has an important impact on the performance of lithium-ion batteries. important influence. The uniformity of dispersion of each component in the electrode slurry directly affects the processing performance of the electrode piece. The mixing process affects product quality by more than 30% in the entire production process of lithium-ion batteries, and is the most important in the entire production process. link. In the electrode manufacturing of lithium-ion batteries, the positive and negative electrode slurries are basically composed of active materials, polymer adhesives, conductive agents, etc. The mixing process of electrode slurry is roughly divided into two types:

The basic process of the wet mixing process is to first mix and stir materials such as adhesives and conductive agents, then add active materials for full mixing and dispersion, and finally add an appropriate amount of solvent to adjust the viscosity to suit coating. This is the current mainstream technology in China.

The basic process of the dry mixing process is to mix the active material, conductive agent and adhesive dry powder, add an appropriate amount of solvent to moisten, add the solvent to disperse and break at a high speed, and dilute to adjust the viscosity.

In the conventional dry mixing process, in the wetting step, improper selection of solvent amount, stirring speed and time can easily cause quality problems, which are closely related to the particle size, size distribution, specific surface area, etc. of the raw materials. These parameters are slightly different. Changes, the corresponding solvent amount and stirring process conditions also need to be adjusted. If too much solvent is added in the first step, the particle agglomerates will not be easily dispersed, resulting in quality problems such as large slurry fineness and uneven distribution of conductive agent. If too little solvent is added in the first step, the wetting and stirring force will be strong, and the adhesive will not be fully dispersed and dissolved, or the long chain of the adhesive will be damaged, resulting in problems with the viscosity and stability of the slurry.

The wet pulping process takes less time, is simpler, has good slurry fluidity and fewer bubbles. However, the problem with the wet stirring process is that due to the large surface area of the conductive agent, it is easy to absorb the solvent, resulting in poor fluidity of the solvent. After adding the active material, it is difficult to achieve a uniformly dispersed state. Under the same solid content conditions, the viscosity of the slurry is higher than that of the dry pulping process.

The current lithium battery homogenization equipment has a complex structure and low efficiency.

Contents of the invention

In view of the above-mentioned shortcomings currently existing, the present invention provides a lithium battery homogenization equipment and a homogenization method thereof, which can improve the effect and efficiency of the homogenization, improve the production efficiency, improve the adaptability to the viscosity of the homogenate, and have a simple and compact structure.

In order to achieve the above objects, embodiments of the present invention adopt the following technical solutions:

A lithium battery homogenizing equipment, used for homogenizing lithium battery materials, the lithium battery homogenizing equipment includes a device main body, a control system is provided on the device main body, a homogenizer is provided inside the device main body, and a homogenizer is provided outside the device main body. A powder tank assembly and a liquid tank assembly are provided. The powder tank assembly and the liquid tank assembly are respectively connected to the homogenizer. The control system is connected to the homogenizer, the powder tank assembly, and the liquid tank assembly respectively.

According to one aspect of the present invention, the powder tank assembly includes a powder tank, a powder valve, and a powder pipe. The powder valve is installed on the powder pipe, and the powder valve is connected to the control system. One end of the tube is connected to the powder tank, and the other end is connected to the homogenizer.

According to one aspect of the present invention, the liquid tank assembly includes a liquid tank, a liquid valve, and a liquid pipe. The liquid valve is installed on the liquid pipe, and the liquid valve is connected to the control system. One end of the liquid pipe is connected to the liquid tank, and the other end of the liquid pipe is connected to the liquid tank. One end is connected to the homogenizer.

According to one aspect of the present invention, the homogenizer includes a homogenizer motor, a rotor, a stator, and a casing. One end of the homogenizer motor is connected to the control system, and the other end is connected to the rotor. The rotor is cooperatively connected to the stator, and the two ends are connected to the stator. A dispersion cavity is formed between them, the stator is fixed in the housing, the homogeneous motor is connected to one side of the housing, and the rotor is located in the housing.

According to one aspect of the present invention, the housing is provided with a powder inlet, a liquid inlet, and a slurry outlet. The powder inlet is connected to a powder pipe, the liquid inlet is connected to a liquid pipe, and the powder inlet, The liquid inlet and slurry outlet are respectively connected with the dispersion chamber.

A lithium battery homogenization method includes the following steps:

Put a certain amount of powder into the powder tank and a certain amount of liquid into the liquid tank;

Open the liquid valve to allow liquid to enter the homogenizer;

Start the homogenizer;

After the preset negative pressure is reached in the homogenizer, open the powder valve so that the powder enters the homogenizer and is fully mixed with the liquid;

The slurry formed after mixing enters the liquid tank;

The slurry in the liquid tank repeatedly enters the homogenizer for homogenization;

After all the powder enters the homogenizer, close the powder valve;

The homogenizer maintains the predetermined speed and runs for a maintenance time;

Turn off the homogenizer, and the mixed slurry will be discharged through the slurry outlet and collected.

According to one aspect of the present invention, the preset negative pressure is 0.4mbar, the predetermined speed is 28-30m/s, and the maintenance time is 5-10 minutes.

Advantages of the implementation of the present invention: Based on the high-speed homogenizer, the original process is optimized, so that the liquid and powder are homogenized by the horizontal lithium battery homogenizer to form good dispersion. That is, start the homogenizer first, and after reaching the set speed, open the liquid valve or liquid control butterfly valve of the liquid tank assembly, so that the liquid components flow in the system to form a cycle. At this time, a negative pressure is formed in the cavity, and the powder is opened. Valve or powder control butterfly valve, the active material powder, that is, the powder will be sucked into the dispersion chamber and efficiently dispersed under the action of the high shear force of the stator and rotor. After all the powder has entered, close the powder control butterfly valve. At this time, the slurry has been fully mixed. After a period of high-speed homogenization, the lithium battery slurry is mixed. The present invention can improve the effect and efficiency of the homogenate, improve production efficiency, and improve the adaptability to the viscosity of the homogenate, so that the slurry is mixed more evenly. The structure of the present invention is also simpler and more compact, easy to disassemble and assemble, and occupies a small space. save costs.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. Those of ordinary skill in the art can also obtain other drawings based on these drawings without exerting creative efforts.

Figure 1 is a schematic structural diagram of a lithium battery homogenization equipment according to the present invention;

Figure 2 is a schematic structural diagram of the homogenizer according to the present invention;

Figure 3 is a schematic diagram of the homogenization method of the present invention.

The names corresponding to the serial numbers in the figure are as follows:

1. Equipment main body; 2. Control system; 3. Homogenizer; 31. Homogenization motor; 32. Rotor; 33. Stator; 34. Shell; 35. Dispersion chamber; 4. Powder tank assembly; 41. Powder Body tank; 42. Powder valve; 43. Powder pipe; 5. Liquid tank assembly; 51. Liquid tank; 52. Liquid valve; 6. Powder inlet; 7. Liquid inlet; 8. Slurry outlet.

Implementation

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

As shown in Figures 1, 2, and 3, a lithium battery homogenizing equipment is used for homogenizing lithium battery materials. The lithium battery homogenizing equipment includes an equipment body 1, and a control system 2 is provided on the equipment body 1. The equipment main body 1 is provided with a homogenizer 3 inside, and a powder tank assembly 4 and a liquid tank assembly 5 are provided outside the equipment main body 1. The powder tank assembly 4 and the liquid tank assembly 5 are connected to the homogenizer 3 respectively. , the control system 2 is connected to the homogenizer 3, the powder tank assembly 4, and the liquid tank assembly 5 respectively. The equipment has a simpler and more compact structure, is easy to disassemble and assemble, occupies a small space and saves costs.

In practical applications, the powder tank assembly 4 includes a powder tank 41, a powder valve 42, and a powder pipe 43. The powder valve 42 is installed on the powder pipe 43, and the powder valve 42 is connected to the control system 2. One end of the powder pipe 43 is connected to the powder tank 41 and the other end is connected to the homogenizer 3. The powder pipe 43 is used as a powder conveying channel between the powder tank 41 and the homogenizer 3. The powder valve 42 is used for starting and stopping powder transportation and for limiting the powder. The powder valve 42 is selected according to the actual situation, and a conventional butterfly valve can be used.

In practical applications, the liquid tank assembly 5 includes a liquid tank 51, a liquid valve 52, and a liquid pipe. The liquid valve 52 is installed on the liquid pipe. The liquid valve 52 is connected to the control system 2. One end of the liquid pipe is connected to the liquid tank 51. The other end is connected to the homogenizer 3. The liquid pipe is used as a liquid transportation channel between the liquid tank 51 and the homogenizer 3. The liquid valve 52 is used for starting and stopping liquid transportation and for limiting the liquid. The liquid valve 52 Depending on the actual situation, conventional butterfly valves can be used.

In practical applications, the shapes of the powder tank 41 and the liquid tank 51 are not limited, and both are determined according to the actual situation. The powder tank 41 is used to store powder, and the liquid tank 51 is used to store liquid. The powder and liquid are both lithium battery materials. The method of storing powder before the operation of the powder tank 41 can be done by manual dumping or pumping through pipelines. The specific method depends on the actual situation; the method of storing liquid before the operation of the liquid tank 51 is the same as that of the powder tank 41 before operation. Store powder in a consistent manner.

In practical applications, the homogenizer 3 includes a homogenizer motor 31, a rotor 32, a stator 33, and a housing 34. One end of the homogenizer motor 31 is connected to the control system 2, and the other end is connected to the rotor 32. The rotor 32 is connected to the control system 2. The stator 33 is matched and connected, forming a dispersion cavity 35 therebetween. The stator 33 is fixed in the housing 34 , the homogeneous motor 31 is connected to one side of the housing 34 , and the rotor 32 is located in the housing 34 . The homogeneous motor 31 is a high-speed motor that can drive the rotor 32 to rotate at high speed. The rotor 32, the stator 33, and the dispersion chamber 35 are not limited in structural shape and depend on the actual situation. The dispersion chamber 35 is used as a place for dispersion and mixing of powder and liquid. The rotor 32 and the stator 33 can rotate relative to each other at high speed and generate high shear force, which is used to fully mix the powder and liquid and the lithium ion slurry.

In practical applications, the homogenizer 3 is installed horizontally inside the equipment main body 1, and the powder tank 41 and the liquid tank 51 are installed vertically outside the equipment main body 1. The shape of the equipment main body 1 is not limited, it is determined according to the actual situation, and is used for the installation and support of the entire equipment. The homogenizer 3 is a horizontal homogenizer 3 with a height less than or equal to 1.5 meters. The specific size of the homogenizer 3 is determined according to the actual situation, or based on both the powder tank 41 and the liquid tank 51 It depends on the capacity and layout spacing.

In practical applications, the casing 34 of the homogenizer 3 is provided with a pressure gauge. The pressure gauge is connected to the inside of the casing 34 and is used to measure the internal negative pressure of the homogenizer 3, which facilitates personnel to intuitively understand the homogenizer 3. Internal pressure conditions.

In practical applications, PLC numerical control system can be used as control system 2. The powder valve 42 and the liquid valve 52 can be opened and closed automatically through the control system 2, or can be opened and closed manually. The control system 2 can control the rotation of the homogenizing motor 31 . Controlling the work of each component through the control system 2 makes the entire process more programmed, standardized, less error-prone, and more convenient and practical to operate.

In practical applications, the housing 34 is provided with a powder inlet 6, a liquid inlet 7, and a slurry outlet 8. The powder inlet 6 is connected to the powder pipe 43, the liquid inlet 7 is connected to the liquid pipe, and the powder inlet 6 is connected to the liquid pipe. The body inlet 6, the liquid inlet 7, and the slurry outlet 8 are connected to the dispersion chamber 35 respectively. The powder inlet 6 and the liquid inlet 7 are respectively used for powder and liquid to enter the dispersion chamber 35 of the homogenizer 3. The slurry outlet 8 is used to discharge the mixed lithium slurry after mixing. A collection device can be installed inside the main body 1 of the device or outside the entire device, and the collection device is connected to the slurry outlet 8 for collecting the uniformly mixed lithium ion slurry.

The working flow of the homogenizer 3 of the present invention is as follows: when the liquid enters the dispersion chamber 35 through the liquid inlet 7 and the powder enters the dispersion chamber 35 through the powder inlet 6, the homogenizer motor 31 is controlled to rotate at high speed through the control system 2 , driving the rotor 32 to rotate at high speed, causing a high shear force to be formed between the rotor 32 and the stator 33, so that the liquid and powder are efficiently dispersed and mixed in the dispersion chamber 35, and the slurry formed after mixing is discharged through the slurry outlet 8 and processed collect.

A lithium battery homogenization method based on the above lithium battery homogenizer equipment includes the following steps:

Put a certain amount of powder into the powder tank 41, and put a certain amount of liquid into the liquid tank 51;

Open the liquid valve 52 to allow the liquid to enter the dispersion chamber 35 of the homogenizer 3;

Start the homogenizer 3 through the control system 2. The starting linear speed is about 10m/s. After 5 seconds of starting, the linear speed will reach 28-30m/s. The final specific value of the linear speed depends on the viscosity of the material;

At this time, a negative pressure is formed in the homogenizer 3. After the negative pressure in the homogenizer 3 reaches 0.4 mbar, the powder valve 42 is opened through the control system 2, so that the powder enters the dispersion chamber 35 of the homogenizer 3 and mixes with the liquid. Mix thoroughly;

The lithium ion slurry formed after mixing enters the liquid tank 51;

The lithium ion slurry in the liquid tank 51 re-enters the homogenizer 3 for homogenization, then enters the liquid tank 51, and then re-enters the homogenizer 3 for homogenization, and so on;

After all the powder has entered the homogenizer 3, that is, after the required amount of powder in the powder tank 41 has all entered the homogenizer 3, the powder valve 42 is closed through the control system 2;

The homogenizer 3 maintains a speed of 28-30m/s and runs for 5-10 minutes, which is convenient for the lithium battery slurry to be fully homogenized and mixed. The length of the maintenance time can be adjusted according to the total amount of slurry, or the maintenance time is based on the material in the liquid tank. Depends on volume;

The homogenizer 3 is closed, and the mixed slurry is discharged through the slurry outlet 8 and collected.

In practical applications, a stirrer is provided in the liquid tank 51 so that the lithium ion slurry formed after mixing enters the liquid tank 51 and is fully stirred again. After the mixed slurry enters the liquid tank 51, a circulation process is performed, that is, the liquid circulates throughout the system, and a part of the powder enters the homogenizer 3 each time to be mixed with the liquid until all the powder enters the liquid tank 51 to form a uniform quality. The negative pressure data in the homogenizer 3 can be read through the pressure gauge. Generally, the range of the negative pressure in the homogenizer 3 is between 0.1-0.4mbar.

In practical applications, the flow rate of the machine comes from the linear speed of the machine, that is, RPM, and the flow rate can be controlled by controlling the speed. At the same time, the negative pressure of the homogeneous cavity also comes from the speed of the machine, because the fast-flowing liquid takes away the air and forms a negative pressure, so the main way to adjust the machine is to adjust the machine when the temperature is limited (high speed will cause a relatively large temperature rise, So it has to control the speed under the conditions of speed control). The effects achieved by the equipment of the present invention by controlling the rotation speed are as shown in the following table:

The same material of the same volume

Same volume of different materials

Among them, LFP, CNT, NCM and NMP are all conventional lithium ion electrode materials. LFP is lithium iron phosphate cathode material, CNT is carbon nanotube conductive slurry, NCM is Ni-Co-Mn ternary cathode material, and NMP is N- Methylpyrrolidone.

Compared with the existing double planetary mixer, the equipment of the present invention reduces the total homogenization time from 200 minutes to about 45 minutes, which greatly improves the efficiency. At the same time, the equipment of the present invention has a compact design and occupies a small space, which can solve the problem of double planetary mixer. Planetary mixers can cause problems with high plant heights.

The comparison of parameters such as production capacity and energy consumption between the equipment of the present invention and the equipment of the prior art is as shown in the following table:

Compared with the existing double planetary disperser and twin-screw mixer, the equipment of the present invention increases the production capacity, reduces the floor space, greatly reduces energy consumption, and improves production efficiency.

Advantages of the implementation of the present invention: Based on the high-speed homogenizer 3, the original process is optimized, so that the liquid and powder are homogenized by the horizontal lithium battery homogenizer 3 to form a good dispersion. That is, first open the homogenizer 3, and after reaching the set speed, open the liquid valve 52 or the liquid control butterfly valve of the liquid tank assembly 5, so that the liquid components flow in the system to form a cycle. At this time, a negative pressure is formed in the cavity. By opening the powder valve 42 or the powder control butterfly valve, the active material powder will be sucked into the dispersion chamber 35 and efficiently dispersed under the high shear force of the stator and rotor. After all the powder has entered, close the powder control butterfly valve. At this time, the slurry has been fully mixed. After a period of high-speed homogenization, the lithium battery slurry is mixed. The present invention can improve the effect and efficiency of the homogenate, improve production efficiency, and improve the adaptability to the viscosity of the homogenate, so that the slurry is mixed more evenly. The structure of the present invention is also simpler and more compact, easy to disassemble and assemble, and occupies a small space. save costs.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any skilled person familiar with the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. All are covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims (7)

A lithium battery homogenizing equipment used for homogenizing lithium battery materials. The lithium battery homogenizing equipment includes a device main body (1). It is characterized in that a control system (2) is provided on the device main body (1). The device A homogenizer (3) is provided inside the main body (1), and a powder tank assembly (4) and a liquid tank assembly (5) are provided outside the equipment main body (1). The powder tank assembly (4) and liquid The tank assembly (5) is connected to the homogenizer (3) respectively, and the control system (2) is connected to the homogenizer (3), the powder tank assembly (4), and the liquid tank assembly (5) respectively. A lithium battery homogenization equipment according to claim 1, characterized in that the powder tank assembly (4) includes a powder tank (41), a powder valve (42), and a powder pipe (43). The powder valve (42) is installed on the powder pipe (43). The powder valve (42) is connected to the control system (2). One end of the powder pipe (43) is connected to the powder tank (41) and the other end is connected to the powder tank (41). One end is connected to the homogenizer (3). A lithium battery homogenization equipment according to claim 1, characterized in that the liquid tank assembly (5) includes a liquid tank (51), a liquid valve (52), and a liquid pipe, and the liquid valve (52) is installed On the liquid pipe, the liquid valve (52) is connected to the control system (2), one end of the liquid pipe is connected to the liquid tank (51), and the other end is connected to the homogenizer (3). A lithium battery homogenizing equipment according to claim 1, characterized in that the homogenizer (3) includes a homogenizing motor (31), a rotor (32), a stator (33), and a casing (34), One end of the homogeneous motor (31) is connected to the control system (2), and the other end is connected to the rotor (32). The rotor (32) and the stator (33) are cooperatively connected, and a dispersion cavity (35) is formed between the two. , the stator (33) is fixed in the casing (34), the homogeneous motor (31) is connected to one side of the casing (34), and the rotor (32) is located in the casing (34). A lithium battery homogenization equipment according to claim 2 or 3 or 4, characterized in that the housing (34) is provided with a powder inlet (6), a liquid inlet (7), and a slurry outlet (8) , the powder inlet (6) is connected to the powder pipe (43), the liquid inlet (7) is connected to the liquid pipe, the powder inlet (6), liquid inlet (7), and slurry outlet (8) are respectively connected with the dispersion chamber (35). A lithium battery homogenization method, characterized in that it includes the following steps: Put a certain amount of powder into the powder tank (41), and put a certain amount of liquid into the liquid tank (51); Open the liquid valve (52) to allow the liquid to enter the homogenizer (3); Start the homogenizer(3); After the preset negative pressure is reached in the homogenizer (3), open the powder valve (42) so that the powder enters the homogenizer (3) and is fully mixed with the liquid; The slurry formed after mixing enters the liquid tank (51); The slurry in the liquid tank (51) repeatedly enters the homogenizer (3) for homogenization; After all the powder enters the homogenizer (3), close the powder valve (42); The homogenizer (3) maintains a predetermined speed and operates for a maintenance time; Close the homogenizer (3), and the mixed slurry is discharged through the slurry outlet (8) and collected. A lithium battery homogenization method according to claim 6, characterized in that the preset negative pressure is 0.4mbar, the predetermined speed is 28-30m/s, and the maintenance time is 5-10 minutes.