Preparation process of water-based lithium ion battery positive electrode slurry

Abstract

The invention discloses a preparation process of water-based lithium ion battery positive electrode slurry, and relates to the technical field of lithium batteries, a water-based binder and a dispersant with a chemical formula I are adopted, the water-based lithium ion battery positive electrode slurry takes water as a solvent, the water-based binder is adopted, and the dispersant is added, so that the stability of the slurry is enhanced; the solid content of the product is increased, the slurry distribution is uniform, the performance of the lithium ion battery is improved, the problem of non-uniform dispersion of the positive electrode slurry is solved, the water consumption can be saved, the energy consumption is reduced, and the advantages of low cost and environmental friendliness are achieved. The solid content of a water-based lithium ion battery positive electrode product prepared from the water-based lithium ion battery positive electrode slurry is increased, and the lithium ion battery is excellent in performance.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium batteries, and in particular to a process for preparing aqueous lithium-ion battery positive electrode slurry. Background Art

[0002] Lithium-ion batteries are widely used in various applications in our lives, including smartphones, laptops, electric vehicles, electric bicycles, and medical applications. Advances in lithium-ion battery technology have made these devices so integral to our lives. They not only make our lives more convenient, but are also tools with significant implications for society.

[0003] Currently, in lithium-ion battery production, cathode slurries are often made using an oil-based system, with PVDF commonly used as the electrode binder and NMP as the dispersant. NMP, a highly volatile organic solvent, has drawbacks such as high cost, environmental pollution, and difficulty in recycling. Furthermore, it can cause uneven dispersion of the cathode slurry in lithium batteries.

[0004] Chinese patent publication number CN105261760B discloses an aqueous composite positive electrode current collector for lithium-ion batteries, a positive electrode sheet, a preparation method thereof, and a lithium-ion battery. The aqueous composite positive electrode current collector for lithium-ion batteries disclosed in this patented technology is prepared using a preparation method comprising the following steps: adding a binder to a solvent and mixing uniformly to obtain a binder solution; the mass ratio of the binder to the solvent is 1:10-30; adding a conductive agent to the prepared binder solution, mixing uniformly, grinding and emulsifying to obtain a conductive slurry; the mass ratio of the conductive agent to the binder is 1-99:1; and coating the prepared conductive slurry on the surface of the positive electrode current collector and drying. This aqueous composite positive electrode current collector for lithium-ion batteries significantly improves the poor flexibility of aqueous positive electrode sheets, while also enhancing coating adhesion, reducing battery internal resistance, and improving high-rate discharge performance and cycle performance. However, this patented technology still fails to address the requirement for increasing the solids content of the positive electrode slurry, resulting in poor stability and uniformity.

[0005] Therefore, in view of the shortcomings of the existing technology, it is necessary to provide a preparation process for aqueous lithium-ion battery positive electrode slurry to overcome the shortcomings of the existing technology. Summary of the Invention

[0006] The purpose of the present invention is to avoid the shortcomings of the prior art and provide a preparation process of an aqueous lithium-ion battery positive electrode slurry and a lithium battery positive electrode prepared by the slurry. The aqueous lithium-ion battery positive electrode slurry and the lithium battery positive electrode prepared by the slurry can enhance the solid content of the positive electrode slurry of the lithium battery, improve the stability and uniformity of the positive electrode slurry, reduce the preparation cost, and prevent pollution to the environment.

[0007] One of the above-mentioned purposes of the present invention is achieved through the following technical means.

[0008] Provided is an aqueous lithium-ion battery positive electrode slurry, the dispersant has the molecular formula:

[0009]

[0010] Wherein, R6 and R5 are set to at least one of H or CH3;

[0011] R2, R3, and R4 are set to Na + 、Li + , H, CH3, C2H5, C3H7 or C4H9;

[0012] n, x, m are 0 or 1 respectively, and n+x+m>0;

[0013] 5≤z≤40, 0≤y≤40, the average molecular weight of the dispersant is 6500-10500, and the glass transition temperature of the dispersant is 80-115°C;

[0014] Preferably, the aqueous lithium-ion battery positive electrode slurry is composed of a main material part and deionized water;

[0015] Calculated by weight percentage, the main material contains: 94%-99% active material, 0.5%-3% binder, 0.4%-3% conductive agent, and 0.1%-0.5% dispersant;

[0016] Deionized water accounts for 20%-40% of the total weight of the main material and deionized water;

[0017] Preferably, the binder is set to be any one or more of a mixture of SBR styrene-butadiene rubber and CMC sodium carboxymethyl cellulose or a mixture of styrene-butadiene rubber and lithium hydroxymethyl cellulose or gelatin or polyacrylic acid and its lithium and sodium salts or xanthan gum or polymethyl methacrylate;

[0018] Preferably, in the above aqueous lithium-ion battery positive electrode slurry, the molecular formula of the binder is:

[0019] wherein R1 is H, CH3, C2H5, C3H7 or C4H9, and m is 5-20.

[0020] Preferably, the active material comprises any one or more of lithium iron phosphate, NCM, NCA, lithium manganese oxide, lithium iron manganese phosphate, and lithium cobalt oxide.

[0021] Preferably, the conductive agent is any one or more of acetylene black, Super-P, conductive graphite, CNT, Ketjen black, graphene or VGCF.

[0022] Another object of the present invention is achieved by the following technical means:

[0023] A preparation process for the aqueous lithium-ion battery positive electrode slurry is provided, comprising the following steps:

[0024] Step S1, adding a dispersant to deionized water, stirring at a speed of 500-1000 rpm for 5-30 min to obtain a mixture M1;

[0025] Step S2, adding a conductive agent to the mixture M1, and stirring at a stirring speed of 1500-2000 rpm for 30-60 minutes to obtain a mixture M2;

[0026] Step S3: Add the binder to the mixture M2 and stir at a stirring speed of 1500-2000 rpm for 30-60 minutes.

[0027] A mixture M3 is obtained;

[0028] Step S4: Divide the active substance into 4-8 portions and add them to the mixture M3 in 4-8 portions. Stir at 2000-4000 rpm for 5-15 minutes after each addition. Continue stirring for 30-60 minutes after all the addition is completed.

[0029] Preferably, the preparation process of the aqueous lithium-ion battery positive electrode slurry comprises the following steps:

[0030] Step S1, adding a dispersant to deionized water, stirring at a speed of 600-800 rpm for 15-20 min to obtain a mixture M1;

[0031] Step S2, adding a conductive agent to the mixture M1, and stirring at a stirring speed of 1600-1800 rpm for 35-50 minutes to obtain a mixture M2;

[0032] Step S3, adding the binder to the mixture M2, and stirring at a stirring speed of 1600-1800 rpm for 35-50 minutes to obtain a mixture M3;

[0033] Step S4: Divide the active substance into 5-6 portions and add them to the mixture M3 in 5-6 portions. Stir at 2500-3500 rpm for 8-10 minutes after each addition. Continue stirring for 35-45 minutes after all the additions are completed.

[0034] The present invention also provides an aqueous lithium-ion battery positive electrode, which is prepared using the aqueous lithium-ion battery positive electrode slurry and the preparation process of the aqueous lithium-ion battery positive electrode slurry.

[0035] The aqueous lithium ion battery positive electrode slurry of the present invention adopts an aqueous binder and a dispersant of the chemical formula I. The aqueous lithium ion battery positive electrode slurry uses water as a solvent and adopts an aqueous binder. Through the addition of the dispersant, the slurry stability is enhanced, the solid content of the product is increased, the slurry is evenly distributed, the performance of the lithium ion battery is improved, and the problem of uneven dispersion of the positive electrode slurry is solved. In addition, water consumption can be saved, energy consumption can be reduced, and the cost is low and the environment is friendly. The aqueous lithium ion battery positive electrode product prepared by the aqueous lithium ion battery positive electrode slurry of the present invention has an increased solid content and excellent lithium ion battery performance. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the contents in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0037] Example 1.

[0038] A water-based lithium-ion battery positive electrode slurry uses a water-based binder and a dispersant having the molecular formula:

[0039]

[0040] Wherein, R6 and R5 are respectively set to at least one of H or CH3. As is common knowledge in the art, the distribution setting here should be understood as follows: R6 and R5 can be H at the same time, or R6 and R5 can be CH3 at the same time, or R6 is H and R5 is CH3, or R6 is CH3 and R5 is H;

[0041] R2, R3, and R4 are respectively set to at least one of Na+, Li+, H, CH3, C2H5, C3H7, or C4H9. The understanding of the respective settings of R2, R3, and R4 is similar to the above-mentioned respective settings of R6 and R5, and will not be repeated here.

[0042] n, x, and m are respectively 0 or 1, and n+x+m>0; 5≤z≤40, 0≤y≤40, the average molecular weight of the dispersant is 6500-10500, and the glass transition temperature of the dispersant is 80-115°C.

[0043] The dispersant has a special molecular structure, which contains benzene rings, carboxyl groups, sulfonic acid groups and other anchoring segments that form a strong bond with the surface of the active material particles. At the same time, the solvated chain segments such as polyether can form steric hindrance.

[0044] To prevent particle agglomeration, the specially designed molecular length and glass transition temperature give the dispersant molecules superior strength and length, achieving better dispersion. Experimental results confirm that the aqueous lithium-ion battery cathode slurry produced using this dispersant can resolve the problem of uneven cathode slurry dispersion. By adding this dispersant, the stability of the aqueous lithium-ion battery cathode slurry is enhanced, the solids content of the product is increased, and the slurry is evenly distributed, effectively improving lithium-ion battery performance.

[0045] It should be noted that any dispersant that conforms to the chemical structure of Formula I meets the requirements for being a dispersant in this application. There are many ways to synthesize dispersants, and any method that can synthesize the chemical structure of Formula I meets the requirements of the dispersant preparation method in this embodiment.

[0046] Here, a method for preparing a dispersant is provided, but other possible preparation methods are not excluded.

[0047] The preparation steps of the dispersant are:

[0048] A mixed solution, solution 1, and solution 2 were prepared separately; the mixed solution was then heated to 70° C. and kept warm; while the mixed solution was kept warm, solution 1 and solution 2 were added dropwise to the mixed solution at a controlled rate within 1 hour;

[0049] Finally, the temperature was raised to 80° C. and the reaction was carried out for 5 h to obtain the dispersant.

[0050] The mixed solution is prepared as follows: styrene or α-methylstyrene is added to deionized water according to the molecular formula ratio of the dispersant, 1%-5% by mass of benzoyl peroxide is added, the mixture is stirred evenly, and the mixture is heated to 60° C. and then kept warm to obtain a mixed solution.

[0051] Solution 1 is prepared as follows: carboxyl and sulfonate reaction monomers are prepared according to the molecular formula ratio of the dispersant, added into deionized water, placed in a container, and stirred evenly to obtain solution 1.

[0052] Solution 2 is prepared as follows: an ethylene oxide solution having a molar ratio of the dispersant molecular formula is placed in another container to obtain solution 2.

[0053] The specific composition of the aqueous lithium-ion battery positive electrode slurry is as follows, consisting of a main material part and deionized water;

[0054] Calculated by weight percentage, the main material contains: 94%-99% active material, 0.5%-3% binder, 0.4%-3% conductive agent, and 0.1%-0.5% dispersant;

[0055] Deionized water accounts for 20%-40% of the total weight of the main material and deionized water.

[0056] The active material comprises any one or more of lithium iron phosphate, NCM, NCA, lithium manganate, lithium iron manganese phosphate, and lithium cobalt oxide. It should be noted that the active material can be any one of the above-mentioned lithium iron phosphate, NCM, NCA, lithium manganate, lithium iron manganese phosphate, and lithium cobalt oxide, or a combination thereof. When composed of two or more components, as long as the overall content of each component is within the range of 94%-99%, the present formula is satisfied.

[0057] The binder may be a mixture of SBR styrene-butadiene rubber and CMC sodium carboxymethyl cellulose; preferably, the molar ratio of SBR styrene-butadiene rubber to CMC sodium carboxymethyl cellulose is 0.7-1-1:1.

[0058] The binder can be a mixture of SBR styrene-butadiene rubber and CMC carboxymethyl cellulose lithium; preferably, the molar ratio of SBR styrene-butadiene rubber to CMC carboxymethyl cellulose lithium is 0.7-1:1.

[0059] The binder may also be any one or more of gelatin, polyacrylic acid and its lithium or sodium salt, xanthan gum or polymethyl methacrylate.

[0060] The aqueous lithium-ion battery positive electrode slurry may also use a binder having the following molecular formula:

[0061] , wherein R1 is H, CH3, C2H5, C3H7 or C4H9, and m is 5-20.

[0062] Specifically, the conductive agent is set to be any one or more of acetylene black, Super-P, conductive graphite, CNT, Ketjen black, graphene or VGCFF.

[0063] The aqueous lithium-ion battery positive electrode slurry uses a dispersant of Formula I. The addition of the dispersant enhances slurry stability, increases product solids content, and evenly distributes the slurry, thereby improving lithium-ion battery performance and resolving the problem of uneven positive electrode slurry dispersion. The aqueous lithium-ion battery positive electrode product prepared using the aqueous lithium-ion battery positive electrode slurry of the present invention has an increased solids content and excellent lithium-ion battery performance.

[0064] Example 2.

[0065] A preparation process for the aqueous lithium-ion battery positive electrode slurry of Example 1 comprises the following steps:

[0066] Step S1, adding a dispersant to deionized water, stirring at a speed of 500-1000 rpm for 5-30 min to obtain a mixture M1;

[0067] Step S2, adding a conductive agent to the mixture M1, and stirring at a stirring speed of 1500-2000 rpm for 30-60 minutes to obtain a mixture M2;

[0068] Step S3, adding the binder to the mixture M2, and stirring at a stirring speed of 1500-2000 rpm for 30-60 minutes to obtain a mixture M3;

[0069] Step S4: Divide the active substance into 4-8 portions and add them to the mixture M3 in 4-8 portions. Stir at 2000-4000 rpm for 5-15 minutes after each addition. Continue stirring for 30-60 minutes after all the addition is completed.

[0070] The aqueous lithium-ion battery positive electrode slurry prepared by the process of the present invention has enhanced slurry stability, increased product solid content, uniform slurry distribution, improved lithium-ion battery performance, and solved the problem of uneven dispersion of positive electrode slurry. The aqueous lithium-ion battery positive electrode product prepared by the aqueous lithium-ion battery positive electrode slurry of the present invention has increased solid content and excellent lithium-ion battery performance.

[0071] Example 3.

[0072] A preparation process for the aqueous lithium-ion battery positive electrode slurry of Example 1 specifically comprises the following steps:

[0073] Step S1, adding a dispersant to deionized water, stirring at a speed of 600-800 rpm for 15-20 min to obtain a mixture M1;

[0074] Step S2, adding a conductive agent to the mixture M1, and stirring at a stirring speed of 1600-1800 rpm for 35-50 minutes to obtain a mixture M2;

[0075] Step S3, adding the binder to the mixture M2, and stirring at a stirring speed of 1600-1800 rpm for 35-50 minutes to obtain a mixture M3;

[0076] Step S4: Divide the active substance into 5-6 portions and add them to the mixture M3 in 5-6 portions. Stir at 2500-3500 rpm for 8-10 minutes after each addition. Continue stirring for 35-45 minutes after all the additions are completed.

[0077] The aqueous lithium-ion battery positive electrode slurry prepared by the process of the present invention has enhanced slurry stability, increased product solid content, uniform slurry distribution, improved lithium-ion battery performance, and solved the problem of uneven dispersion of positive electrode slurry. The aqueous lithium-ion battery positive electrode product prepared by the aqueous lithium-ion battery positive electrode slurry of the present invention has increased solid content and excellent lithium-ion battery performance.

[0078] Example 4.

[0079] A process for preparing an aqueous lithium-ion battery positive electrode slurry, the other features of which are the same as those of any one of Examples 2 or 3, except that:

[0080] The specific steps in this embodiment are as follows:

[0081] Step S1, 0.2% The mixture was added into 32% deionized water and stirred at a speed of 500 rpm for 20 minutes to obtain a mixture M1.

[0082] Step S2: adding 1% super-P and 0.5% CNT to the mixture M1 obtained in step S1, and stirring at a stirring speed of 1500 rpm for 40 minutes to obtain a mixture M2.

[0083] Step S3, adding 1.5% gelatin to the mixture M2 obtained in step S2, and then stirring at a stirring speed of 2000 rpm for 30 minutes to obtain a mixture M3.

[0084] Step S4, adding 96.8% lithium iron phosphate into the mixture M3 obtained in step S3 in 5 batches, stirring at 2000 rpm for 5 minutes after each addition, and finally continuing stirring for 50 minutes after the addition is completed.

[0085] The positive electrode material slurry of this embodiment has good stability, can increase the solid content of the product, and at the same time the slurry is evenly distributed, and the prepared lithium-ion battery has good performance.

[0086] Example 5.

[0087] A process for preparing an aqueous lithium-ion battery positive electrode slurry, the other features of which are the same as those of Example 2 or 3, except that, in this embodiment, specifically:

[0088] Step S1, 0.15%

[0089] The mixture was added into 30% deionized water and stirred at a speed of 500 rpm for 20 minutes to obtain a mixture M1.

[0090] Step S2, adding 1% super-P and 0.5% CNT to the mixture M1 obtained in step S1, stirring at a speed of 1500 rpm, and stirring for 40 minutes to obtain a mixture M2;

[0091] Step S3, adding 1.5% gelatin to the mixture M2 obtained in step S2, and then stirring at a stirring speed of 2000 rpm for 30 minutes to obtain a mixture M3;

[0092] Step S4, adding 96.8% lithium iron phosphate into the mixture M3 obtained in step S3 in 5 batches, stirring at 2000 rpm for 15 minutes after each addition, and continuing stirring for 50 minutes after all additions are completed.

[0093] The positive electrode material slurry of this embodiment has good stability, can increase the solid content of the product, and at the same time the slurry is evenly distributed, and the prepared lithium-ion battery has good performance.

[0094] Example 6.

[0095] A process for preparing an aqueous lithium-ion battery positive electrode slurry, the other features of which are the same as those of Example 2 or 3, except that, in step S1, 0.1% of The mixture was added into 31% deionized water, and stirring was started at a stirring speed of 700 rpm for 25 minutes to obtain a mixture M1.

[0096] Step S2: adding 1.5% CNT to the mixture M1 obtained in step S1, and stirring at a stirring speed of 2000 rpm for 5 minutes to obtain a mixture M2.

[0097] Step S3, adding 1.5% of SBR styrene butadiene rubber and CMC sodium carboxymethyl cellulose (the weight ratio of SBR styrene butadiene rubber to CMC sodium carboxymethyl cellulose is 1:1) to the mixture M2 obtained in step S2, and then stirring at a stirring speed of 2000 rpm for 30 minutes to obtain a mixture M3.

[0098] Step S4, adding 96.9% lithium iron phosphate into the mixture M3 obtained in step S3 in 4 batches, stirring at 3000 rpm for 10 minutes after each addition, and continuing to stir for 40 minutes after the addition is completed.

[0099] The positive electrode material slurry of this embodiment has good stability, can increase the solid content of the product, and at the same time the slurry is evenly distributed, and the prepared lithium-ion battery has good performance.

[0100] Example 7.

[0101] A process for preparing an aqueous lithium-ion battery positive electrode slurry, the other features of which are the same as those of Example 2 or 3, except that, in step S1, 0.1% of The mixture was added into 30% deionized water and stirred at a speed of 700 rpm for 25 minutes to obtain a mixture M1.

[0102] Step S2: adding 1.6% CNT to the mixture M1 obtained in step S1, and then stirring at a stirring speed of 2000 rpm for 45 minutes to obtain a mixture M2.

[0103] Step S3, 1.4% The mixture was added to the mixture obtained in step S2, and stirred at a stirring speed of 2000 rpm for 30 min to obtain a mixture M3.

[0104] Step S4, adding 96.9% lithium iron phosphate into the mixture M3 obtained in step S3 in 4 batches, stirring at 3000 rpm for 10 minutes after each addition, and continuing stirring for 40 minutes after all additions are completed.

[0105] Comparative Example 1:

[0106] Step S1: adding 1.5% CNT to 33% deionized water, stirring at a speed of 2000 rpm for 50 minutes.

[0107] Step S2: add 1.5% SBR styrene butadiene rubber and CMC sodium carboxymethyl cellulose (1:1) into step S1, stir at 2000 rpm, and stir for 30 minutes.

[0108] Step S3, adding 97% lithium iron phosphate into step S2 in 6 batches, stirring at 3000 rpm for 15 minutes after each addition, and continuing stirring for 50 minutes after the addition is completed.

[0109] The slurries prepared in Examples 4 to 7 were subjected to performance testing and compared with the viscosity results of Comparative Example 1. The specific results are shown in Table 1:

[0110] Table 1

[0111]

[0112] Test results show that the aqueous lithium-ion battery cathode slurry formulated in this invention has an appropriate viscosity, with minimal viscosity change over 24 hours, meeting the requirements for aqueous lithium-ion battery cathode slurries. At the same solids content, the dispersion is excellent, and the slurry's performance after 24 hours also meets the requirements for battery cathode materials.

[0113] It can be seen that the aqueous lithium-ion battery positive electrode slurry of the present invention has enhanced slurry stability, increased product solid content, uniform slurry distribution, and improved lithium-ion battery performance. The aqueous lithium-ion battery positive electrode product prepared by the aqueous lithium-ion battery positive electrode slurry of the present invention has increased solid content and excellent lithium-ion battery performance.

[0114] Example 8.

[0115] The experimental results show that the technical solutions of the present invention can produce good technical effects. Tables 2 and 3 below list some examples and experimental results.

[0116] The compositions of different aqueous lithium-ion battery cathode slurries are shown in Table 2.

[0117] Table 2

[0118]

[0119] Formulas P1 to P6 were prepared using process 1, process 2, and process 3, respectively, to obtain the corresponding samples Pij, where i ranges from 1 to 6 and j ranges from 1 to 3. Pij represents the sample obtained by formula Pi using process j.

[0120] The process parameters of process 1 are: step S1 stirring speed 800 rpm, stirring time 10 min; step S2 stirring

[0121] Stir at a speed of 1500 rpm for 30 minutes; in step S3, stir at a speed of 1800 rpm for 40 minutes; in step S4, divide the active substance into 5 parts and add them to the mixture M3 in 5 times. Stir at 2000 rpm for 5 minutes after each addition. Continue stirring for 38 minutes after all the additions are completed.

[0122] The process parameters of process 2 are as follows: step S1, stirring speed 900 rpm, stirring time 15 min; step S2, stirring speed 1800 rpm, stirring for 50 min; step S3, stirring speed 1800 rpm, stirring for 60 min; step S4, dividing the active substance into 6 parts, adding them to the mixture M3 in 6 times, stirring at 3000 rpm for 10 minutes after each addition, and continuing stirring for 50 minutes after all additions are completed.

[0123] The process parameters of process 3 are as follows: step S1, stirring speed 950 rpm, stirring time 30 min; step S2, stirring speed 2000 rpm, stirring for 55 min; step S3, stirring speed 1500 rpm, stirring for 50 min; step S4, dividing the active substance into 8 parts, adding them to the mixture M3 in 8 times, stirring at 4000 rpm for 15 minutes after each addition, and continuing stirring for 60 minutes after all additions are completed.

[0124] The performance results of the obtained sample slurry are shown in Table 3.

[0125] Table 3

[0126]

[0127] The test results in Table 3 show that the viscosity of the aqueous lithium-ion battery cathode slurry prepared under the corresponding formula and process is

[0128] The viscosity change over 24 hours was not significant, meeting the requirements for aqueous lithium-ion battery cathode slurries. At the same solid content, the dispersion effect was good, and the performance of the slurry after 24 hours also met the requirements for battery cathode materials.

[0129] It can be seen that the aqueous lithium-ion battery positive electrode slurry of the present invention has enhanced slurry stability, increased product solid content, uniform slurry distribution, and improved lithium-ion battery performance. The aqueous lithium-ion battery positive electrode product prepared by the aqueous lithium-ion battery positive electrode slurry of the present invention has increased solid content and excellent lithium-ion battery performance.

[0130] Example 9.

[0131] A water-based lithium-ion battery positive electrode is prepared according to the preparation process of the water-based lithium-ion battery positive electrode slurry described in the above embodiment 1 and the water-based lithium-ion battery positive electrode slurry described in any one of embodiments 2-7.

[0132] The aqueous lithium-ion battery positive electrode prepared by the above scheme can improve the performance of the lithium-ion battery.

[0133] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A process for preparing an aqueous lithium-ion battery positive electrode slurry, characterized in that: The following steps are involved: Step S1, adding a dispersant to deionized water, stirring at a speed of 500-1000 rpm for 5-30 min to obtain a mixture M1; Step S2, adding a conductive agent to the mixture M1, and stirring at a stirring speed of 1500-2000 rpm for 30-60 minutes to obtain a mixture M2; Step S3, adding the binder to the mixture M2, and stirring at a stirring speed of 1500-2000 rpm for 30-60 minutes to obtain a mixture M3; Step S4: Divide the active substance into 4-8 portions and add them to the mixture M3 in 4-8 portions. Stir at 2000-4000 rpm for 5-15 minutes after each addition. Continue stirring for 30-60 minutes after all the addition is completed.

2. The process for preparing an aqueous lithium-ion battery positive electrode slurry according to claim 1, wherein: Step S1: adding a dispersant to deionized water, and stirring the mixture at a stirring speed of 600-800 rpm for 15-20 min to obtain a mixture M1.

3. The process for preparing an aqueous lithium-ion battery positive electrode slurry according to claim 1, wherein: Step S2: adding a conductive agent to the mixture M1, and stirring the mixture at a stirring speed of 1600-1800 rpm for 35-50 minutes to obtain a mixture M2.

4. The process for preparing an aqueous lithium-ion battery positive electrode slurry according to claim 1, wherein: Step S3: adding the binder to the mixture M2, and stirring at a stirring speed of 1600-1800 rpm for 35-50 minutes to obtain a mixture M3.

5. The process for preparing an aqueous lithium-ion battery positive electrode slurry according to claim 1, wherein: Step S4: Divide the active substance into 5-6 portions and add them to the mixture M3 in 5-6 portions. Stir at 2500-3500 rpm for 8-10 minutes after each addition. Continue stirring for 35-45 minutes after all the additions are completed.

Images