Pulping process and pulping equipment for horizontal high-efficiency high-solid-content lithium battery slurry

Abstract

The invention belongs to the technical field of pulping of lithium battery slurry, and particularly relates to a pulping process and pulping equipment of horizontal high-efficiency high-solid-content lithium battery slurry. The pulping process comprises the following steps: obtaining a corresponding active substance, a conductive agent and a binder according to the characteristics of lithium battery positive and negative electrode slurry; adding the obtained active substance, conductive agent and binder powder into a positive and negative horizontal kneading tank, and stirring until the powder is uniformly mixed; adding an infiltrating solvent into a positive and negative horizontal kneading tank, and obtaining fully infiltrated slurry under the efficient kneading action of equipment; adding a corresponding diluting solvent into the infiltrated slurry until diluted slurry is obtained; and conveying the diluted slurry to a corresponding dispersion system for efficient dispersion to finally obtain the lithium battery slurry with high solid content and good stability, and conveying the lithium battery slurry to a corresponding finished product tank. The problems that in the prior art, due to the fact that powder and diluted solutions are directly mixed and stirred, the solid content is low, and sedimentation and particle aggregation phenomena are prone to occurring are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of lithium battery slurry pulping, and specifically relates to a horizontal high-efficiency and high-solid lithium battery slurry pulping process and pulping equipment. Background Art

[0002] The lithium battery industry provides new solutions for the development of new energy technologies. As the most critical pulping process in the lithium battery industry, the quality of the pulp is directly related to the performance of the lithium battery. Therefore, how to make high-quality and high-performance lithium battery pulp has always been the goal of lithium battery manufacturers. At present, the market adopts the traditional P / D double planetary pulping process, high-speed circulation pulping process and twin-screw high-efficiency pulping process for lithium battery pulp.

[0003] Among them, the traditional P / D double planetary pulping process pre-mixes the powder, and then prepares the slurry through kneading high viscosity dilution, dispersion and other processes. The preparation time is long and the efficiency is low. In the high-speed circulation pulping process, the powder is added to the high-speed circulating solvent, and then the slurry is prepared through the high-speed dispersion and other processes of the equipment. The heat exchange area of ​​the high-speed dispersion process is small, and the slurry temperature rises quickly, which affects the slurry quality. In the twin-screw efficient pulping process, the powder falls into the twin-screw pulping system evenly according to the target ratio, and then a certain proportion of solvent is added, and the slurry is prepared through the high-speed meshing of the twin screws. The high-speed rotation between the twin screws causes the risk of wear between the screws, resulting in metal foreign matter mixed into the slurry, so that the metal foreign matter dissolves into the slurry, affecting the internal resistance and electrochemical performance of the battery. In addition, the surfaces of active materials in the current market, especially lithium iron phosphate and high nickel ternary, are modified accordingly. The surface structure of the material will be destroyed under the long-term high-speed shearing action of current homogenization equipment such as high-speed circulation and thin-film dispersion systems, and the slurry stability is poor.

[0004] The lithium battery market is developing rapidly, and various lithium battery raw materials are also updated and iterated quickly. The quality of raw materials on the market is also gradually uneven. Therefore, under the premise of pursuing production efficiency and capacity, how to maximize the performance of various materials on the market and how to avoid destroying the structure of the materials have posed greater challenges to pulping equipment and processes. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the prior art such as long preparation time and poor slurry stability caused by the destruction of material structure, and to provide a slurrying process and slurrying equipment for horizontal high-efficiency and high-solid lithium battery slurry, which fully utilizes the role of horizontal kneading tanks for positive and negative electrodes, adds the slurry multiple times, stirs in stages, and independently disperses the positive and negative slurries, and has high dispersion efficiency.

[0006] The technical solution adopted by the present invention to solve its technical problem is:

[0007] As a first aspect, a horizontal high-efficiency high-solid lithium battery slurry preparation process comprises the following steps:

[0008] Step 1: Obtain the corresponding active material, conductive agent, and binder according to the characteristics of the lithium battery positive and negative electrode slurry;

[0009] Step 2: Add the obtained active material, conductive agent, and binder powders into the positive and negative electrode horizontal kneading tank, and stir until the powders are evenly mixed;

[0010] Step 3: adding a wetting solvent to the positive and negative electrode horizontal kneading tank, and obtaining a fully wetted wetting slurry through efficient kneading in the positive and negative electrode horizontal kneading tank;

[0011] Step 4: adding a corresponding dilution solvent to the impregnation slurry, and diluting and stirring the impregnation slurry through a positive and negative electrode horizontal kneading tank until a diluted slurry is obtained;

[0012] Step 5: Transport the diluted slurry to the corresponding dispersion system for efficient dispersion to obtain lithium battery slurry with high solid content and good stability, and transport it to the corresponding finished product tank.

[0013] Furthermore, the mass ratio of the active material, the conductive agent and the binder in step 1 is:

[0014] Active substances: 95% to 98%;

[0015] Conductive agent: 0.5%~1%;

[0016] Binder: 1%~2%.

[0017] Furthermore, the conductive agent is one of conductive carbon black SP and CNTs;

[0018] The binder is one of PVDF, CMC and SBR.

[0019] Furthermore, when a lithium battery positive electrode slurry is to be prepared, the active material is one or more of lithium iron phosphate, ternary, lithium manganese iron phosphate, and lithium-rich manganese-based;

[0020] The infiltration solvent and the dilution solvent are both N-methylpyrrolidone.

[0021] Furthermore, when it is necessary to prepare a negative electrode slurry for a lithium battery, the active material is one or more of graphite and silicon-based;

[0022] The infiltration solvent and the dilution solvent are both deionized water.

[0023] Furthermore, when preparing lithium battery positive electrode slurry, the corresponding dispersion system includes a positive electrode circulation tank connected to the positive and negative electrode horizontal kneading tank pipeline, and a positive electrode disperser connected to the positive electrode circulation tank pipeline;

[0024] When preparing lithium battery negative electrode slurry, the corresponding dispersion system includes a negative electrode dispersion tank connected to the positive and negative electrode horizontal kneading tank pipelines.

[0025] Furthermore, the tank body of the positive and negative electrode horizontal kneading tank, the tank body of the positive electrode circulation tank, the tank body of the negative electrode dispersion tank, and the tank body, tank cover and machine seal of the positive electrode dispersion machine are all equipped with a cooling water guide strip jacket system; the slurry temperature at any outlet of the positive electrode circulation tank, the positive electrode dispersion machine and the negative electrode dispersion tank is 5°C to 10°C higher than the slurry temperature at the corresponding feed inlet 。

[0026] As a second aspect, a lithium battery slurry preparation device adopts the above-mentioned horizontal high-efficiency and high-solid lithium battery slurry preparation process.

[0027] Furthermore, the preparation equipment of lithium battery slurry includes a powder feeding mechanism, a positive and negative electrode horizontal kneading tank, a positive electrode circulation tank, a positive electrode disperser, a positive electrode finished product tank, a negative electrode dispersion tank and a negative electrode finished product tank;

[0028] The positive and negative electrode horizontal kneading tank is provided with a plurality of feed ports and at least one discharge port, and the powder feeding mechanism is connected with the feed ports through pipelines; the positive electrode finished tank, the positive electrode disperser and the positive electrode circulation tank are connected with pipelines in sequence, and then connected with the discharge port pipeline of the positive and negative electrode horizontal kneading tank, and the positive electrode disperser is rotationally connected with the positive electrode circulation pipe; the negative electrode finished tank is connected with the negative electrode dispersion tank and then connected with the discharge port on the positive and negative electrode horizontal kneading tank.

[0029] Furthermore, a liquid on-off valve is provided on the connecting pipeline between the powder feeding mechanism and the positive and negative electrode horizontal kneading tank, on the connecting pipeline between the positive and negative electrode horizontal kneading tank and the positive electrode circulation tank, and on the connecting pipeline between the positive and negative electrode horizontal kneading tank and the negative electrode dispersion tank;

[0030] Power pumps are provided on the discharge pipelines of the positive and negative electrode horizontal kneading tanks, the discharge pipeline of the positive electrode circulation tank, the discharge pipeline of the positive electrode disperser, the circulation pipelines between the positive electrode disperser and the positive electrode circulation tank, and the discharge pipeline of the negative electrode dispersion tank.

[0031] The beneficial effects of the slurry making process and slurry making equipment of the horizontal high-efficiency high-solid lithium slurry of the present invention are:

[0032] The present invention first adds raw materials into the positive and negative electrode kneading tank for powder mixing to obtain a uniform powder slurry, then adds a small amount of wetting solvent into the positive and negative electrode kneading tank, infiltrates the powder slurry, and after sufficient infiltration, forms an infiltrated slurry, and finally adds a diluting solvent to form a uniformly mixed diluting slurry. The preparation process of the present invention abandons the method of directly mixing and stirring each powder and diluting solution or adding the powder to a high-speed circulating solution in the prior art, adds the powder and the diluting solvent in stages, and then adds the infiltrating solvent between the powder slurry and the diluting slurry to form an infiltrating slurry. The whole is stirred step by step in three stages, and sufficient mixing of the slurry can be achieved without adding more diluting solvent, so that the solid content of the lithium battery slurry prepared by the present invention is higher than the solid content of the lithium battery slurry prepared by the existing preparation process, thereby ensuring the coating quality and electrode structure of the positive and negative electrode materials of the battery, ensuring the uniform distribution of the electrode materials, avoiding the phenomenon of uneven thickness or material accumulation, thereby improving the energy density, cycle life and safety performance of the battery, and the lithium battery slurry prepared by the preparation process of the present invention has high stability and long storage time. The invention solves the problems in the prior art of directly mixing and stirring the powders and the diluted solutions, such as low solid content, low packing density of the coated electrode, easy sedimentation and particle agglomeration, and disadvantages of rolling and high-compacted material requirements.

[0033] The preparation process of the present invention adds the powder material, the wetting solvent and the dilution solvent in stages, that is, on the basis of the evenly mixed powder slurry, the wetting solvent is added to preliminarily wet the powder slurry, and after complete wetting, the dilution solvent is added to dilute the wetted slurry. Compared with the preparation process of the prior art, the stirring time is shorter, and the slurry making efficiency is effectively improved. Finally, the dilution solution is transported to the corresponding independent dispersion system for independent dispersion, so that the slurry can be fully and efficiently dispersed in a very short time, and there is no wear of the twin-screw on the slurry, thereby ensuring the structural integrity of the slurry material. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0035] Figure 1 It is a flow chart of the steps of the preparation process in an embodiment of the present invention.

[0036] Figure 2 It is a process flow chart of the preparation process in the embodiment of the present invention.

[0037] Figure 3 It is a schematic structural diagram of a pulping device according to an embodiment of the present invention.

[0038] Figure 4 This is the backscattered light reference spectrum of the negative electrode slurry prepared in Example 1 of the present invention.

[0039] Figure 5This is a stability test diagram of the negative electrode slurry prepared in Example 1 of the present invention.

[0040] Figure 6 This is the backscattered light reference spectrum of the negative electrode slurry prepared in comparative example 1.

[0041] Figure 7 This is a stability test diagram of the negative electrode slurry prepared in comparative example 1.

[0042] Figure 8 It is a comparison chart of the kinetic stability of the negative electrode slurry of Example 1 of the present invention and Comparative Example 1.

[0043] Fig. 9 It is a radar chart comparing the stability index of the negative electrode slurry of Implementation Example 1 of the present invention and Comparative Example 1.

[0044] Fig.10 This is an electron microscope image of a negative electrode sheet prepared with the negative electrode slurry prepared in Example 1 of the present invention.

[0045] Fig.11 This is an electron microscope image of a slurry-coated electrode sheet prepared by using the negative electrode slurry prepared in comparative example 1 of the present invention.

[0046] Fig.12 This is an electron microscope image of a positive electrode sheet prepared with the positive electrode slurry according to Example 2 of the present invention.

[0047] Fig.13 This is an electron microscope image of a positive electrode sheet prepared with the positive electrode slurry of comparative example 2 of the present invention.

[0048] Fig.14 This is a test record sheet of the adhesion of the positive electrode prepared in Example 2 of the present invention.

[0049] Fig.15 This is a test record of the adhesion of the positive electrode sheet prepared in comparative example 2 of the present invention.

[0050] In the figure: 1. Powder feeding mechanism, 2. Positive and negative electrode horizontal kneading tank, 3. Positive electrode circulation tank, 4. Positive electrode disperser, 5. Positive electrode finished product tank, 6. Negative electrode dispersion tank, 7. Negative electrode finished product tank, 8. Liquid circuit on-off valve, 9. Power pump. DETAILED DESCRIPTION

[0051] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0052] like Figure 1-Figure 3 The specific embodiment of the slurrying process of a horizontal high-efficiency and high-solid lithium slurry of the present invention shown includes the following steps:

[0053] Step 1: Obtain the corresponding active material, conductive agent, and binder according to the characteristics of the lithium battery positive and negative electrode slurry;

[0054] Step 2: Add the obtained active material, conductive agent, and binder powders into the positive and negative electrode horizontal kneading tank 2, and stir until the powders are evenly mixed; the stirring time is 10 min to 15 min;

[0055] Step 3: adding a wetting solvent to the positive and negative electrode horizontal kneading tank 2, and obtaining a fully wetted wetting slurry through efficient kneading in the positive and negative electrode horizontal kneading tank 2;

[0056] Step 4: adding a corresponding dilution solvent to the impregnation slurry, and diluting and stirring the impregnation slurry through the positive and negative electrode horizontal kneading tank 2 until a diluted slurry is obtained;

[0057] Step 5: Transport the diluted slurry to the corresponding dispersion system for efficient dispersion to obtain lithium battery slurry with high solid content and good stability, and transport it to the corresponding finished product tank.

[0058] Each step is described in detail below. In step 1, the corresponding powder is weighed according to the material requirements of the lithium battery positive electrode slurry and the lithium battery negative electrode slurry. The mass ratio of the active material, the conductive agent, and the binder in step 1 is:

[0059] Active substances: 95% to 98%;

[0060] Conductive agent: 0.5%~1%;

[0061] Binder: 1%~2%.

[0062] Among them, the conductive agent is one of conductive carbon black SP and CNTs, the binder is one of PVDF, CMC and SBR, when it is necessary to prepare lithium battery positive electrode slurry, the active material is one or more of lithium iron phosphate, ternary, lithium iron manganese phosphate, and lithium-rich manganese-based. When it is necessary to prepare lithium battery negative electrode slurry, the active material is one or more of graphite and silicon-based.

[0063] It should be further explained that the wetting solvent added to the positive and negative electrode horizontal kneading tank 2 in step three and the dilution solvent added in step four are added according to the requirements of the positive electrode slurry and the negative electrode slurry. The corresponding wetting solvent and dilution solvent can be the same material solvent or different material solvents.

[0064] As a preferred embodiment, when it is necessary to prepare a negative electrode slurry for a lithium battery, deionized water is used as both the soaking solvent and the dilution solvent.

[0065] As a preferred embodiment, when lithium battery positive electrode slurry is to be prepared, N-methylpyrrolidone is used as both the impregnation solvent and the dilution solvent.

[0066] The dispersion system in step 5, specifically when preparing lithium battery positive electrode slurry, the corresponding dispersion system includes a positive electrode circulation tank 3 connected to the positive and negative electrode horizontal kneading tank 2 pipeline, and a positive electrode disperser 4 connected to the positive electrode circulation tank 3 pipeline. The diluted slurry enters the positive electrode circulation tank 3 for stirring and mixing, enters the positive electrode disperser 4 for dispersion, and the dispersed slurry enters the circulation stirring tank again for stirring and mixing. The slurry after stirring and mixing enters the positive electrode disperser 4 for multiple dispersions until it meets the requirements and is transported to the positive electrode finished product tank 5. When preparing lithium battery negative electrode slurry, the corresponding dispersion system includes a negative electrode dispersion tank 6 connected to the positive and negative electrode horizontal kneading tank 2 pipeline, the diluted slurry enters the negative electrode dispersion tank 6 for dispersion treatment, and the dispersed slurry enters the negative electrode finished product tank 7 for storage for standby use.

[0067] The tank body of the positive and negative electrode horizontal kneading tank 2, the tank body of the positive electrode circulation tank 3, the tank body of the negative electrode dispersion tank 6, and the tank body, upper tank cover and machine seal of the positive electrode disperser 4 in this embodiment are all equipped with a cooling water guide strip jacket system. This embodiment optimizes the cooling and temperature reduction module, and adds a cooling water guide strip jacket system to the upper tank cover and machine seal of the positive electrode disperser, which has a large heat exchange area and high cooling efficiency, and further cools the stirred slurry. The overall cooling effect is significant. After efficient circulation, the discharge port temperature is guaranteed to be 5 to 10°C higher than the feed port temperature, which fully meets the process temperature window of the pulping process.

[0068] The preparation equipment of lithium battery slurry based on the preparation process of lithium battery slurry comprises a powder feeding mechanism 1, a positive and negative electrode horizontal kneading tank 2, a positive electrode circulation tank 3, a positive electrode disperser 4, a positive electrode finished product tank 5, a negative electrode dispersion tank 6 and a negative electrode finished product tank 7. The positive and negative electrode horizontal kneading tank 2 is provided with a plurality of feeding ports and at least one discharging port, and the powder feeding mechanism 1 is connected with the feeding port through a pipeline; the positive electrode finished product tank 5, the positive electrode disperser 4 and the positive electrode circulation tank 3 are connected with the discharging port pipeline of the positive and negative electrode horizontal kneading tank 2 in sequence, and the positive electrode disperser 4 is rotatably connected with the positive electrode circulation pipe; the negative electrode finished product tank 7 is connected with the negative electrode dispersion tank 6 and then connected with the discharging port on the positive and negative electrode horizontal kneading tank 2.

[0069] like Figure 3 As shown, it is further explained that in this embodiment, a liquid on-off valve 8 is provided on the connecting pipelines of the powder feeding mechanism 1 and the positive and negative electrode horizontal kneading tank 2, the connecting pipelines of the positive and negative electrode horizontal kneading tank 2 and the positive electrode circulation tank 3, and the connecting pipelines of the positive and negative electrode horizontal kneading tank 2 and the negative electrode dispersion tank 6. A power pump 9 is provided on the discharge pipeline of the positive and negative electrode horizontal kneading tank 2, the discharge pipeline of the positive electrode circulation tank 3, the discharge pipeline of the positive electrode disperser 4, the circulation pipeline between the positive electrode disperser 4 and the positive electrode circulation tank 3, and the discharge pipeline of the negative electrode dispersion tank 6. The provision of the liquid on-off valve 8 and the power pump 9 ensures the normal transportation of the slurry.

[0070] Embodiment 1

[0071] In the first embodiment, a negative electrode slurry is prepared by using the above-mentioned preparation equipment and the above-mentioned preparation method, such as Figure 4 The backscattered light reference spectrum of the negative electrode slurry is shown. Figure 4 It can be seen that the negative electrode slurry prepared in Example 1 has a high overlap of each scanning curve, indicating that the slurry has high stability and no particle agglomeration and slurry sedimentation occurs during the process. Figure 5 This is a stability test diagram of the negative electrode slurry prepared in Example 1.

[0072] Comparative Example 1

[0073] In the first comparative example, the negative electrode slurry is prepared by using the prior art P / D double planetary slurry making equipment, that is, the rod-type dispersion disk preparation process. Figure 6 is the backscattered light reference spectrum of the negative electrode slurry of this comparative example 1, from Figure 6 It can be seen that during the slurry test of the P / D equipment, a trough obviously appeared at the top, indicating that sedimentation occurred during the slurry test. At the same time, the process curve fluctuated greatly, indicating that there was agglomeration of particles in the slurry and the overall slurry consistency was poor. Figure 7 This is a stability test diagram of the negative electrode slurry prepared in this comparative example 1.

[0074] The TSI stability index represents the overall stability of the slurry (<0.2 is preferred). Figure 8 The comparison diagram of the kinetic stability of the negative electrode slurry of Example 1 and Comparative Example 1 is shown, Fig. 9 The stability index is compared with the radar chart. It can be seen from the results that the stability of the horizontal high-efficiency pulping process pulp (blue curve) is significantly higher than that of the P / D dual planetary pulping process (red curve). The radar chart shows the stability of the top, middle and bottom of the pulp during the test. It can be seen that the TSI index of the pulp at different positions in this embodiment 1 is not much different, which further shows that the stability of the pulp in this embodiment 1 is higher.

[0075] like Fig.10 From the electron microscope image of the negative electrode sheet prepared from the negative electrode slurry prepared in Example 1, it can be seen that after the slurry prepared by the process of Example 1 is applied, the graphite particles are sharp and angular, basically consistent with the particle morphology before homogenization, the particle size distribution is uniform, there is no agglomeration phenomenon, and the carbon black is evenly distributed on the graphite surface in a granular morphology, indicating that when the equipment is used for homogenization, it can achieve a good dispersion effect without destroying the structure of the material.

[0076] Fig.11 This is the electron microscope image of the slurry coated electrode prepared by the twin screw extruder in the comparative example 1 under the same slurry formula. Fig.11 It can be seen that the structure of the active material is destroyed and the edges and corners of the material are severely worn.

[0077] The preparation process of the present invention adds the powder material, the wetting solvent and the dilution solvent in stages, that is, on the basis of the evenly mixed powder slurry, the wetting solvent is added to preliminarily wet the powder slurry, and after complete wetting, the dilution solvent is added to dilute the wetted slurry. Compared with the preparation process of the prior art, the stirring time is shorter, and the slurry making efficiency is effectively improved. Finally, the dilution solution is transported to the corresponding independent dispersion system for independent dispersion, so that the slurry can be fully and efficiently dispersed in a very short time, and there is no wear of the twin-screw on the slurry, thereby ensuring the structural integrity of the slurry material.

[0078] Embodiment 2

[0079] The second embodiment is a positive electrode slurry prepared by using the above-mentioned preparation equipment and the above-mentioned preparation method. Fig.12 This is an electron microscope image of the positive electrode sheet prepared by the positive electrode slurry of Example 2. Fig.12 It can be seen that the electrode material prepared by the positive electrode slurry of Example 2 has a uniform particle size distribution, and there is no particle agglomeration, indicating that the particle structure is complete and evenly dispersed. The CNT carbon tube fibers in the electrode are perfectly stretched and evenly covered on the surface of the active material, playing a good "bridging role", improving the conductivity of the electrode and effectively reducing the internal resistance of the electrode.

[0080] Comparative Example 2

[0081] This comparative example 2 adopts the same pulping formula as that of the embodiment 2, and adopts a high-speed circulation pulping machine in the prior art to prepare the positive electrode slurry. The electron microscope image of the prepared positive electrode sheet is shown in FIG. Fig.13 It can be seen that the particle size distribution is uneven, and a large amount of "powder"-like substances appear. It is speculated that the sintered layer on the surface of the active material was sheared and peeled off, and the CNT in the electrode was completely broken. The longest fiber in the electron microscope is only 1um, and the rest are shorter, losing its inherent advantage of "bridging conductive effect".

[0082] The electrode adhesion test of the electrode prepared in Example 2 and Comparative Example 2 is as follows: Fig.14 and 15 As shown, the adhesion of the electrode in the second embodiment is 50 N / m on average, which is significantly greater than the adhesion of the electrode in the second comparative example prepared by a twin-screw device, which is 6 N / m on average. It can be concluded that the components and the binder in the second embodiment are evenly dispersed, so that the electrode has a higher adhesion and is not prone to powdering and material shedding during the electrochemical cycle, thereby ensuring the capacity and safety of the battery to a great extent.

[0083] The preparation method of the present invention first adds raw materials into the positive and negative electrode kneading tank for powder mixing to obtain a uniform powder slurry, then adds a small amount of wetting solvent into the positive and negative electrode kneading tank, infiltrates the powder slurry, and after sufficient infiltration, forms an infiltrated slurry, and finally adds a diluting solvent to form a uniformly mixed diluent slurry. The preparation process of the present invention abandons the method of directly mixing and stirring each powder and diluent solution or adding the powder to a high-speed circulation solution in the prior art, adds the powder and the diluent solvent in stages, and then adds the infiltrating solvent between the powder slurry and the diluent slurry to form an infiltrated slurry. The whole is stirred step by step in three stages, and sufficient mixing of the slurry can be achieved without adding more diluting solvent, so that the solid content of the lithium battery slurry prepared by the present invention is higher than the solid content of the lithium battery slurry prepared by the existing preparation process, thereby ensuring the coating quality and electrode structure of the positive and negative electrode materials of the battery, ensuring the uniform distribution of the electrode materials, avoiding the phenomenon of uneven thickness or material accumulation, thereby improving the energy density, cycle life and safety performance of the battery, and the lithium battery slurry prepared by the preparation process of the present invention has high stability and long storage time.

[0084] It should be understood that the specific embodiments described above are only used to explain the present invention, and are not used to limit the present invention. Obvious changes or modifications derived from the spirit of the present invention are still within the protection scope of the present invention.

Claims

1. A horizontal high-efficiency and high-solid lithium slurry slurry making process, characterized in that: The following steps are involved: Step 1: Obtain the corresponding active material, conductive agent, and binder according to the characteristics of the lithium battery positive and negative electrode slurry; Step 2: Add the obtained active material, conductive agent, and binder powders into the positive and negative electrode horizontal kneading tank (2), and stir until the powders are evenly mixed; Step 3: adding a wetting solvent to the positive and negative electrode horizontal kneading tank (2), and obtaining a fully wetted wetting slurry through efficient kneading in the positive and negative electrode horizontal kneading tank (2); Step 4: adding a corresponding dilution solvent to the impregnation slurry, and diluting and stirring the impregnation slurry through the positive and negative electrode horizontal kneading tank (2) until a diluted slurry is obtained; Step 5: Transport the diluted slurry to the corresponding dispersion system for efficient dispersion to obtain lithium battery slurry with high solid content and good stability, and transport it to the corresponding finished product tank.

2. The slurry making process of a horizontal high-efficiency and high-solid lithium slurry according to claim 1 is characterized in that: The mass ratio of the active material, the conductive agent and the binder in step 1 is: Active substances: 95% to 98%; Conductive agent: 0.5%~1%; Binder: 1%~2%.

3. A horizontal high-efficiency and high-solid lithium slurry preparation process according to claim 2, characterized in that: The conductive agent is one of conductive carbon black SP and CNTs; The binder is one of PVDF, CMC and SBR.

4. A horizontal high-efficiency high-solid lithium slurry preparation process according to claim 3, characterized in that: When a lithium battery positive electrode slurry is to be prepared, the active material is one or more of lithium iron phosphate, ternary, lithium manganese iron phosphate, and lithium-rich manganese-based; The infiltration solvent and the dilution solvent are both N-methylpyrrolidone.

5. The process for preparing a horizontal high-efficiency and high-solid lithium slurry according to claim 3, characterized in that: When it is necessary to prepare a negative electrode slurry for a lithium battery, the active material is one or more of graphite and silicon-based; The infiltration solvent and the dilution solvent are both deionized water.

6. The process for preparing a horizontal high-efficiency and high-solid lithium slurry according to claim 1, characterized in that: When preparing lithium battery positive electrode slurry, the corresponding dispersion system comprises a positive electrode circulation tank (3) connected to the pipeline of the positive and negative electrode horizontal kneading tank (2), and a positive electrode disperser (4) connected to the pipeline of the positive electrode circulation tank (3); When preparing lithium battery negative electrode slurry, the corresponding dispersion system includes a negative electrode dispersion tank (6) connected to the positive and negative electrode horizontal kneading tank (2) through pipelines.

7. The process for preparing a horizontal high-efficiency and high-solid lithium slurry according to claim 1, characterized in that: The tank body of the positive and negative electrode horizontal kneading tank (2), the tank body of the positive electrode circulation tank (3), the tank body of the negative electrode dispersion tank (6), and the tank body, tank cover and machine seal of the positive electrode dispersion machine (4) are all equipped with a cooling water guide strip jacket system; the slurry temperature at any outlet of the positive electrode circulation tank (3), the positive electrode dispersion machine (4) and the negative electrode dispersion tank (6) is 5°C to 10°C higher than the slurry temperature at the corresponding feed inlet 。 8. A lithium battery slurry preparation device, characterized in that: A horizontal high-efficiency and high-solid lithium slurry slurry making process as described in any one of claims 1 to 7 is adopted.

9. The lithium battery slurry preparation device according to claim 8, characterized in that: It comprises a powder feeding mechanism (1), a positive and negative electrode horizontal kneading tank (2), a positive electrode circulation tank (3), a positive electrode disperser (4), a positive electrode finished product tank (5), a negative electrode dispersion tank (6) and a negative electrode finished product tank (7); The positive and negative electrode horizontal kneading tank (2) is provided with a plurality of feed ports and at least one discharge port, and the powder feeding mechanism (1) is connected to the feed ports through pipelines; the positive electrode finished product tank (5), the positive electrode disperser (4) and the positive electrode circulation tank (3) are connected in sequence through pipelines and then connected to the discharge port pipeline of the positive and negative electrode horizontal kneading tank (2), and the positive electrode disperser (4) is rotatably connected to the positive electrode circulation pipe; the negative electrode finished product tank (7) is connected to the negative electrode dispersion tank (6) and then connected to the discharge port on the positive and negative electrode horizontal kneading tank (2).

10. The lithium battery slurry preparation device according to claim 9, characterized in that: Liquid on-off valves (8) are provided on the connecting pipelines between the powder feeding mechanism (1) and the positive and negative electrode horizontal kneading tanks (2), the connecting pipelines between the positive and negative electrode horizontal kneading tanks (2) and the positive electrode circulation tank (3), and the connecting pipelines between the positive and negative electrode horizontal kneading tanks (2) and the negative electrode dispersion tank (6); A power pump (9) is provided on the discharge pipeline of the positive and negative electrode horizontal kneading tank (2), the discharge pipeline of the positive electrode circulation tank (3), the discharge pipeline of the positive electrode disperser (4), the circulation pipeline between the positive electrode disperser (4) and the positive electrode circulation tank (3), and the discharge pipeline of the negative electrode dispersion tank (6).

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