Method for rapidly determining optimal additive amount of battery slurry adhesive

Abstract

The invention discloses a method for quickly determining the optimal addition amount of a battery slurry adhesive, which comprises the following steps: taking out a plurality of samples in the process of stirring and dispersing slurry; sequentially pouring the samples onto a rotational rheology tester; the test distance of the rotational rheology tester is set to be 0.8 mm, the temperature is set to be 20 DEG C + / -1, the deformation quantity is set to be within a viscoelastic interval range, the frequency scanning interval is 0.01 Hz-100 Hz, a point is taken as log (points are taken in order of magnitude distribution of 10), and the number of steps is 6; the rotational rheology tester is used for testing to obtain a frequency scanning graph of the slurry, and whether the adding proportion of the binder is reasonable or not is judged by judging the frequency interval of the intersection point of the energy storage modulus and the loss modulus. According to the method for rapidly determining the optimal addition amount of the battery slurry adhesive, whether the slurry ratio is appropriate or not can be tested in real time, the ratio of the adhesive can be synchronously adjusted on line, and the method is suitable for characterization of the battery slurry which is a complex dispersion system.

Description

Technical Field

[0001] The invention belongs to the field of battery testing, and in particular relates to a method for quickly determining the optimal addition amount of a battery slurry adhesive. Background Art

[0002] As battery performance improves, reducing the amount of binder used in battery slurries is a key technological approach to improving overall battery performance, reducing costs, and achieving environmental goals. Its core value lies in balancing battery energy density, lifespan, and safety through material innovation and process optimization, thereby driving the industry towards greener and more efficient development.

[0003] As a key component, the binder dosage must be precisely controlled: excessive addition can lead to excessive slurry viscosity, making coating difficult; insufficient addition can loosen the electrode structure, affecting battery cycle stability. Traditional empirical testing methods, however, suffer from time-consuming and labor-intensive peel strength testing and low test accuracy. This makes it impossible to minimize binder usage without compromising slurry performance, hindering overall battery performance.

[0004] Therefore, it is urgent to design a method to quickly determine the optimal addition amount of battery slurry adhesive to solve the above-mentioned problems. Summary of the Invention

[0005] In order to solve the technical problems mentioned in the background technology that the peel strength test of the traditional method is time-consuming and labor-intensive, the test accuracy is low, and it is impossible to minimize the amount of binder without affecting the slurry performance, a method for quickly determining the optimal addition amount of battery slurry adhesive is provided to solve the problem of quickly determining the optimal addition amount of battery slurry binder.

[0006] To achieve the above-mentioned purpose, the specific technical solution of the method for quickly determining the optimal addition amount of battery slurry adhesive of the present invention is as follows: A method for quickly determining the optimal addition amount of a battery slurry adhesive comprises the following steps: S1. Taking out a plurality of samples during the process of stirring and dispersing the slurry; S2. Pour the samples onto the rotational rheology tester in sequence; S3. Set the rotational rheometer to a test spacing of 0.8 mm, a temperature of 20°C ± 1, a deformation range within the viscoelastic range, a frequency sweep range of 0.01 Hz to 100 Hz, a logarithmic sampling point distribution (with a 10-order distribution), and a step number of 6. The rotational rheology tester tests the frequency sweep diagram of the slurry, and determines whether the binder addition ratio is reasonable by judging the frequency range where the intersection of the storage modulus (G') and the loss modulus (G'').

[0007] Furthermore, in the low-frequency region of 0.01HZ~1Hz, the slurry is in a static state. When the intersection of the storage modulus and the loss modulus appears in the low-frequency region, it indicates that the internal network structure of the slurry is weak and cannot effectively fix the active particles. The slurry will exhibit continuous sedimentation behavior in a static state, which indicates that the amount of binder added to the slurry system is insufficient.

[0008] Furthermore, in the high-frequency region of 10Hz~100Hz, the slurry is in a high-speed shear state during coating. When the intersection of the storage modulus and the loss modulus appears in the high-frequency region, it indicates that the bonding force between the main material particles of the slurry is too large. In this state, the amount of binder added to the slurry system is excessive.

[0009] Furthermore, when the intersection of the storage modulus and the loss modulus appears at 1Hz~10Hz, the slurry is relatively stable and does not affect the coating. The less the amount of binder added, the sooner the intersection of the storage modulus and the loss modulus appears. At the same time, the less the amount of binder added, the smaller the peel strength of the electrode.

[0010] Furthermore, when the peel strength of the electrode is within the requirements of the test outline, the amount of adhesive added corresponding to the minimum frequency value at the intersection of the storage modulus and the loss modulus is the optimal adhesive ratio in the system.

[0011] Furthermore, samples were retained for multiple light tests, and the instability index (TSI) value was used to determine whether the binder-deficient slurry was stable. A TSI value greater than 0.6 indicated that the slurry was unstable, and a TSI value less than 0.6 indicated that the slurry was in a normal state.

[0012] Furthermore, the coating effect of the electrode is observed to determine whether the adhesive is excessive or insufficient. Excessive adhesive will manifest as bulging edges and vertical stripes on the electrode coating, while insufficient adhesive will manifest as easy chip shedding and cracking.

[0013] Furthermore, the number of the multiple samples in step S1 is 5 to 10 groups.

[0014] The method of the present invention for quickly determining the optimal addition amount of a battery slurry adhesive has the following advantages: The test is fast, taking only 3 to 10 minutes, requiring minimal sample size and a short testing process. The storage modulus and loss modulus frequency sweep tests characterize the structural response of materials under dynamic strain, providing a more accurate and direct characterization of the adhesive's adhesion, virtually unaffected by other manufacturing processes. This application allows for real-time testing of the slurry ratio and simultaneous online adjustment of the binder ratio, making it suitable for characterizing complex dispersed systems such as battery slurries. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The present invention is a flow chart of the method for quickly determining the optimal addition amount of battery slurry adhesive. DETAILED DESCRIPTION

[0016] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0017] Those skilled in the art will appreciate that although some embodiments herein include certain features included in other embodiments but not other features, the combination of features from different embodiments is intended to be within the scope of the present invention and to form different embodiments. For example, in the claims, any one of the claimed embodiments may be used in any combination.

[0018] Please refer to the attached Figure 1 The present invention describes a method for rapidly determining the optimal addition amount of a battery paste.

[0019] like Figure 1 As shown, the method for quickly determining the optimal addition amount of the battery slurry adhesive in the present invention includes the following steps: S1. While stirring and dispersing the slurry, take out 5 to 10 samples; S2. Pour the samples onto the Thermo Fisher rotational rheometer in sequence; S3. Set the rotational rheometer to a test spacing of 0.8 mm, a temperature of 20°C ± 1, a deformation range within the viscoelastic range, a frequency sweep range of 0.01 Hz to 100 Hz, a logarithmic sampling point distribution (with a 10-order distribution), and a step number of 6. The rotational rheology tester tests the frequency sweep diagram of the slurry, and determines whether the binder addition ratio is reasonable by judging the frequency range where the intersection of the storage modulus (G') and the loss modulus (G'').

[0020] Furthermore, as a preferred embodiment, in the low-frequency region of 0.01 Hz to 1 Hz, the slurry is in a static state. When the intersection of the storage modulus and the loss modulus appears in the low-frequency region, it indicates that the internal network structure of the slurry is weak and the active particles cannot be effectively fixed. The slurry will exhibit continuous sedimentation behavior in the static state, which indicates that the amount of binder added to the slurry system is insufficient. In the high-frequency region of 10Hz~100Hz, the slurry is in a high-speed shear state during coating. When the intersection of the storage modulus and the loss modulus appears in the high-frequency region, it indicates that the bonding force between the main material particles of the slurry is too large. In this state, the amount of binder added to the slurry system is excessive. When the intersection of the storage modulus and the loss modulus appears at 1Hz~10Hz, the slurry is relatively stable and does not affect the coating. The less the amount of binder added, the sooner the intersection of the storage modulus and the loss modulus appears. At the same time, the less the amount of binder added, the smaller the peel strength of the electrode.

[0021] Among them, when the peel strength of the electrode is within the requirements of the test outline, the amount of adhesive added corresponding to the minimum frequency value at the intersection of the storage modulus and the loss modulus is the optimal adhesive ratio in the system.

[0022] The method for rapidly determining the optimal amount of adhesive to be added to battery slurry allows for rapid testing, with a test process lasting only 3 to 10 minutes, requiring a small sample size and a short test process. The storage modulus and loss modulus frequency sweep tests characterize the structural response of materials under dynamic strain, providing a more accurate and direct characterization of the adhesive's adhesion, virtually unaffected by other manufacturing processes. This application allows for real-time testing of the slurry ratio and simultaneous online adjustment of the adhesive ratio, making it suitable for characterizing complex dispersed systems such as battery slurries.

[0023] The following is further described through multiple groups of examples: Example Description: Example 1 is a conventional system using CMC and SBR as binders. Examples 2 to 4 replace the CMC and SBR binder system in Example 1 with a CMC, PAA, and SBR binder system. The ultimate goal is to find the optimal addition ratio of CMC, PAA, and SBR, reduce the total binder dosage without affecting slurry stability, coating quality, and peel strength, increase the main material ratio, and thus improve the overall performance of the battery.

[0024] Example 1: To make negative electrode slurry, the quality ratio of each raw material is as follows: Graphite:SP:CMC:SBR: =95.5:1:1.6:1.9. The detailed steps for making the slurry are as follows: (1) Add CMC and ultrapure water according to the mass ratio (solid content of the glue is about 1.8%) into a stirring tank and stir for 30 minutes according to the process parameters of rotation 500 rpm and revolution 10 rpm; then stir for 180 minutes according to the process parameters of rotation 1500 rpm and revolution 20 rpm, and all the glue is poured out for use; (2) Graphite and SP were mixed according to the mass ratio and then dry-mixed for 45 min according to the process parameters of rotation 300 rpm and revolution 20 rpm; (3) Add the glue obtained in step (2) into a stirring tank in a certain proportion, pre-mix and add it to the slurry to adjust the solid content of the slurry to about 73%, and knead for 30 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm; (4) Add all the remaining glue in step (2) to the mixing tank for premixing and then add it to the slurry, adjust the solid content of the slurry to about 63%, and stir for 180 minutes according to the process parameters of rotation 500 rpm and revolution 20 rpm; (5) Ultrapure water was added to adjust the solid content to 53%, and the mixture was stirred for 60 min at a rotation speed of 1800 rpm and a revolution speed of 20 rpm. The viscosity was tested and the viscosity range was 4000 Pa / s to 6000 Pa / s. (6) Add SBR and stir slowly for 60 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm.

[0025] The test data is shown in Table 1 below: Test items Intersection point of G' and G'' frequency sweep / Hz Slurry 12h multiple light test TSI / % Pole peel strength / N / m Example 1 1 0.35 5.3 Note: The test outline requires peel strength ≥ 5 N / m, TSI value ≤ 0.6%, and the intersection point of G' and G'' is 1Hz~10 Hz.

[0026] In Example 1, the combined CMC and SBR binders accounted for 3.5%, while the main graphite component accounted for 95.5%. The intersection of the G' and G'' frequency sweeps was 1 Hz. The slurry stability test value TSI was 0.35%, and the electrode peel strength was 5.3 N / m. These values ​​were within the test outline requirements, and the electrode functioned normally after roller coating.

[0027] Example 2: To prepare the negative electrode slurry, the mass ratio of each raw material is as follows: graphite:SP:CMC:PAA:SBR = graphite:SP:CMC:PAA:SBR = 95.5:1:0.5:2:1. The detailed slurry preparation process is as follows: (1) Graphite, SP, and CMC were mixed according to the mass ratio and dry-mixed for 45 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm; (2) A certain proportion of PAA and ultrapure water were premixed at a mass ratio of 1:2 and then added to the slurry to adjust the solid content of the slurry to about 73%. The slurry was kneaded for 30 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm; (3) A certain proportion of PAA and ultrapure water were premixed at a mass ratio of 1:2 and then added to the slurry to adjust the solid content of the slurry to about 63%. The mixture was stirred for 120 min according to the process parameters of 500 rpm rotation and 20 rpm revolution. (4) Add ultrapure water and adjust the solid content to 53%. Stir for 60 min according to the process parameters of rotation 1800 rpm and revolution 20 rpm. Test the viscosity. The viscosity range is 4000 Pa / s ~ 6000 Pa / s. (5) Add SBR and stir slowly for 30 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm.

[0028] The test data is shown in Table 2 below: Test items Intersection point of G' and G'' frequency sweep / Hz Slurry 12h multiple light test TSI / % Pole peel strength / N / m Example 2 17 0.2 13

[0029] Note: The test outline requires peel strength ≥ 5 N / m, TSI value ≤ 0.6%, and the intersection point of G' and G'' is 1Hz~10 Hz.

[0030] In Example 2, the combined amount of CMC, PAA, and SBR binders accounted for 3.5%, while the main graphite material accounted for 95.5%. The bonding ratio was the same as in Example 1. The intersection of the G' and G'' frequency sweeps was 17 Hz, significantly greater than the 1 Hz of Example 1, indicating that the bonding force between the main material particles was much greater than in Example 1 and that the binder dosage was excessive. The slurry stability test value TSI was 0.2%, and the electrode peel strength was 13 N / m, both within the test outline requirements. However, the electrode had a noticeable bulging edge after roller coating.

[0031] Example 3: To prepare the negative electrode slurry, the mass ratio of each raw material is as follows: graphite: SP: CMC: PAA: SBR = 96:1: 0.5: 1.5: 1. The detailed slurry preparation process is as follows: (1) Graphite, SP, and CMC were mixed according to the mass ratio and dry-mixed for 45 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm; (2) A certain proportion of PAA and ultrapure water were premixed at a mass ratio of 1:2 and then added to the slurry to adjust the solid content of the slurry to about 73%. The slurry was kneaded for 30 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm; (3) A certain proportion of PAA and ultrapure water were premixed at a mass ratio of 1:2 and then added to the slurry to adjust the solid content of the slurry to about 63%. The mixture was stirred for 120 min according to the process parameters of 500 rpm rotation and 20 rpm revolution. (4) Add ultrapure water and adjust the solid content to 53%. Stir for 60 min according to the process parameters of rotation 1800 rpm and revolution 20 rpm. Test the viscosity. The viscosity range is 4000 Pa / s ~ 6000 Pa / s. (5) Add SBR and stir slowly for 30 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm.

[0032] The test data is shown in Table 3 below: Test items Intersection point of G' and G'' frequency sweep / Hz Slurry 12h multiple light test TSI / % Pole peel strength / N / m Example 3 3 0.24 7

[0033] Note: The test outline requires peel strength ≥ 5 N / m, TSI value ≤ 0.6%, and the intersection point of G' and G'' is 1Hz~10 Hz.

[0034] In Example 3, the combined amount of CMC, PAA, and SBR binders accounted for 3%, while the main graphite material accounted for 96%. The intersection of the G' and G'' frequency scans was 3 Hz, greater than the 1 Hz of the previous embodiment, indicating that the bonding strength between the main material particles is still greater than that of Example 1. The binder dosage can be appropriately reduced. The slurry stability test value TSI was 2.4%, and the electrode peel strength was 7 N / m, both within the test outline requirements. The electrode was normal after the coating roller pressing.

[0035] Example 4: To prepare the negative electrode slurry, the mass ratio of each raw material is as follows: graphite: SP: CMC: PAA: SBR = 96.3:1:0.5:1.3:0.9. The detailed slurry preparation process is as follows; (1) Graphite, SP, and CMC were mixed according to the mass ratio and then dry-mixed for 45 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm; (2) A certain proportion of PAA and ultrapure water were premixed in a mass ratio of 1:2 and then added to the slurry to adjust the solid content of the slurry to about 73%. The slurry was kneaded for 30 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm; (3) A certain proportion of PAA and ultrapure water were premixed in a mass ratio of 1:2 and then added to the slurry to adjust the solid content of the slurry to about 63%. The mixture was stirred for 120 min according to the process parameters of 500 rpm rotation and 20 rpm revolution. (4) Add ultrapure water and adjust the solid content to 53%. Stir for 60 min according to the process parameters of rotation 1800 rpm and revolution 20 rpm. Test the viscosity. The viscosity range is 4000 Pa / s ~ 6000 Pa / s. (5) Add SBR and stir slowly for 30 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm.

[0036] The test data is shown in Table 4 below: Test items Intersection point of G' and G'' frequency sweep / Hz Slurry 12h multiple light test TSI / % Pole peel strength / N / m Example 4 1.6 0.27 5.7

[0037] Note: The test outline requires peel strength ≥ 5 N / m, TSI value ≤ 0.6%, and the intersection point of G' and G'' is 1Hz~10 Hz.

[0038] In Example 4, the combined amount of CMC, PAA, and SBR binders accounted for 2.7%, while the main graphite material accounted for 96.3%. The intersection of the G' and G'' frequency sweeps was 1.6 Hz, which is greater than the 1 Hz of the previous embodiment. This indicates that the bonding strength between the main material particles is still slightly greater than that in Example 1, and the binder dosage can be appropriately reduced. The slurry stability test value TSI was 2.7%, and the electrode peel strength was 5.7 N / m, both within the test outline requirements. However, the electrode was normal after the coating roller pressing.

[0039] Example 5: To prepare the negative electrode slurry, the mass ratio of each raw material is as follows: graphite:SP:CMC:PAA:SBR = graphite:SP:CMC:PAA:SBR = 96.5:1:0.5:1.3:0.7. The detailed slurry preparation process is as follows: (1) Graphite, SP, and CMC were mixed according to the mass ratio and dry-mixed for 45 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm; (2) A certain proportion of PAA and ultrapure water were premixed at a mass ratio of 1:2 and then added to the slurry to adjust the solid content of the slurry to about 73%. The slurry was kneaded for 30 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm; (3) A certain proportion of PAA and ultrapure water were premixed at a mass ratio of 1:2 and then added to the slurry to adjust the solid content of the slurry to about 63%. The mixture was stirred for 120 min according to the process parameters of 500 rpm rotation and 20 rpm revolution. (4) Add ultrapure water and adjust the solid content to 53%. Stir for 60 min according to the process parameters of rotation 1800 rpm and revolution 20 rpm. Test the viscosity. The viscosity range is 4000 Pa / s ~ 6000 Pa / s. (5) Add SBR and stir slowly for 30 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm.

[0040] The test data is shown in Table 5 below: Test items Intersection point of G' and G'' frequency sweep / Hz Slurry 12h multiple light test TSI / % Pole peel strength / N / m Example 5 1 0.26 5.7

[0041] Note: The test outline requires peel strength ≥ 5 N / m, TSI value ≤ 0.6%, and the intersection point of G' and G'' is 1Hz~10 Hz.

[0042] In Example 5, the combined amount of CMC, PAA, and SBR binders accounted for 2.5%, while the main graphite material accounted for 96.5%, a 1% increase compared to Example 1. The intersection of the G' and G'' frequency sweeps at 1 Hz, the same as in Example 1, indicates that the adhesion between the main material particles is essentially the same as in Example 1. The slurry stability test value TSI was 0.26%, and the electrode peel strength was 5.7 N / m, both within the test outline requirements. However, the electrode functioned normally after roller coating.

[0043] Example 6: To prepare the negative electrode slurry, the mass ratio of each raw material is as follows: graphite: SP: CMC: PAA: SBR = 96.8:1:0.5:1:0.7. The detailed slurry preparation process is as follows: (1) Graphite, SP, and CMC were mixed according to the mass ratio and dry-mixed for 45 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm; (2) A certain proportion of PAA and ultrapure water were premixed at a mass ratio of 1:2 and then added to the slurry to adjust the solid content of the slurry to about 73%. The slurry was kneaded for 30 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm; (3) A certain proportion of PAA and ultrapure water were premixed at a mass ratio of 1:2 and then added to the slurry to adjust the solid content of the slurry to about 63%. The mixture was stirred for 120 min according to the process parameters of 500 rpm rotation and 20 rpm revolution. (4) Add ultrapure water and adjust the solid content to 53%. Stir for 60 min according to the process parameters of rotation 1800 rpm and revolution 20 rpm. Test the viscosity. The viscosity range is 4000 Pa / s ~ 6000 Pa / s. (5) Add SBR and stir slowly for 30 minutes according to the process parameters of rotation 300 rpm and revolution 20 rpm.

[0044] The test data is shown in Table 6 below: Test items Intersection point of G' and G'' frequency sweep / Hz Slurry 12h multiple light test TSI / % Pole peel strength / N / m Example 6 0.75 1.83 1.8

[0045] Note: The test outline requires peel strength ≥ 5 N / m, TSI value ≤ 0.6%, and the intersection point of G' and G'' is 1Hz~10 Hz.

[0046] In Example 6, the combined amount of CMC, PAA, and SBR binders accounted for 2.2%, while the main graphite material accounted for 96.8%. The intersection of the G' and G'' frequency scans was 0.75 Hz, the same as the 1 Hz in the previous example, indicating that the adhesion between the main material particles was poorer than in Example 1. The slurry stability test TSI value ranged from 1.1 (upper slurry sampling test) to 1.83% (lower slurry sampling test), exceeding 0.6%. The slurry was in a continuous sinking state, with poor slurry stability and consistency. The electrode peel strength was 1.8 N / m < 5 N / m, which was outside the test outline requirements. After coating, the electrode exhibited obvious cracks, and the material easily fell off during sampling.

[0047] In summary, Examples 2 to 4 replace the CMC and SBR binder system in Example 1 with a CMC, PAA, and SBR binder system, and Example 5 has the best binder ratio. In Example 5, the total amount of CMC, PAA, and SBR binders accounts for 2.5%, and the graphite main material accounts for 96.5%, which is 1% higher than that in Example 1. The intersection of the G' and G'' frequency scans is 1Hz, which is the same as the 1Hz of the embodiment, indicating that the adhesion effect between the main material particles is basically the same as that in Example 1. The slurry stability test value TSI is 0.26% (Case 5) < 0.35% (Case 1), and the slurry stability is slightly better than that in Example 1. The difference between the electrode peel strength of 5.7N / m (Case 5) and 5.3N / m (Case 1) is not much, and the test values ​​are within the requirements of the test outline. The electrode is normal after the coating roller is pressed.

[0048] In Examples 4 and 5, the binder ratio in Example 4 was 2.7%, and in Example 5, the binder ratio was 2.5%. The intersection of the G' and G'' frequency sweeps was 1.6 Hz in Example 4 and 1 Hz in Example 5, indicating that the bonding strength of the main material particles in Example 4 was greater than that in Example 5, but the peel strength was 5.7 N / m. This indicates that the peel strength value can represent the bonding strength of the binder to a certain extent, but there is a large test deviation and it is greatly affected by the manufacturing process. However, the G' and G'' frequency sweep test can characterize the structural response of the material under dynamic strain, and is more accurate and direct in characterizing the bonding strength of the binder, and is almost unaffected by other manufacturing processes.

[0049] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A method for quickly determining the optimal addition amount of battery slurry adhesive, characterized in that: The following steps are involved: S1. Taking out a plurality of samples during the process of stirring and dispersing the slurry; S2. Pour the samples onto the rotational rheology tester in sequence; S3. Set the rotational rheometer to a test spacing of 0.8 mm, a temperature of 20°C ± 1, a deformation range within the viscoelastic range, a frequency sweep range of 0.01 Hz to 100 Hz, a logarithmic sampling point distribution (with a 10-order distribution), and a step number of 6. The rotational rheology tester tests the frequency sweep diagram of the slurry, and determines whether the binder addition ratio is reasonable by judging the frequency range where the intersection of the storage modulus (G') and the loss modulus (G'').

2. The method for quickly determining the optimal addition amount of battery slurry adhesive according to claim 1, characterized in that: In the low-frequency region of 0.01HZ~1Hz, the slurry is in a static state. When the intersection of the storage modulus and the loss modulus appears in the low-frequency region, it indicates that the internal network structure of the slurry is weak and cannot effectively fix the active particles. The slurry will exhibit continuous sedimentation behavior in a static state, which indicates that the amount of binder added to the slurry system is insufficient.

3. The method for quickly determining the optimal addition amount of battery slurry adhesive according to claim 1, characterized in that: In the high-frequency region of 10Hz~100Hz, the slurry is in a high-speed shear state during coating. When the intersection of the storage modulus and the loss modulus appears in the high-frequency region, it indicates that the bonding force between the main material particles of the slurry is too large. In this state, the amount of binder added to the slurry system is excessive.

4. The method for rapidly determining the optimal addition amount of battery slurry adhesive according to claim 1, characterized in that: When the intersection of the storage modulus and the loss modulus appears at 1Hz~10Hz, the slurry is relatively stable and does not affect the coating. The less the amount of binder added, the sooner the intersection of the storage modulus and the loss modulus appears. At the same time, the less the amount of binder added, the smaller the peel strength of the electrode.

5. The method for quickly determining the optimal addition amount of battery slurry adhesive according to claim 4, characterized in that: When the peel strength of the electrode is within the test outline requirements, the amount of adhesive added corresponding to the minimum frequency value at the intersection of the storage modulus and the loss modulus is the optimal adhesive ratio in the system.

6. The method for rapidly determining the optimal addition amount of battery slurry adhesive according to claim 1, characterized in that: The samples were kept for multiple light tests, and the instability index (TSI) value was used to judge whether the slurry with insufficient binder was stable. A TSI value greater than 0.6 indicated that the slurry was unstable, and a TSI value less than 0.6 indicated that the slurry was in normal condition.

7. The method for rapidly determining the optimal addition amount of battery slurry adhesive according to claim 5, characterized in that: Observe the coating effect of the electrode to determine whether the adhesive is excessive or insufficient. Excessive adhesive will appear as bulging edges and vertical stripes on the electrode coating, while insufficient adhesive will cause the electrode to easily fall off or crack.

8. The method for rapidly determining the optimal addition amount of battery slurry adhesive according to claim 1, characterized in that: The number of the multiple samples in step S1 is 5 to 10 groups.

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