Filling conditioner for battery separator and preparation method thereof

Abstract

The invention relates to the field of electrical elements, and particularly discloses a filling conditioner for a battery separator and a preparation method of the filling conditioner. The filling conditioner for the battery separator comprises the following raw materials in parts by weight: base oil and an antioxidant in a weight ratio of (450-500): (0.5-0.8), the base oil comprises naphthenic base oil and paraffin base oil, the kinematic viscosity of the base oil at 40 DEG C is 152-172 mm < 2 > / s, and the flash point of the base oil is 223-228 DEG C; the antioxidant active substances comprise a diphenyl hindered phenol antioxidant, a phosphite antioxidant and a carbon free radical capturing agent; the preparation method comprises the following steps: equally dividing the antioxidant active substance into three equal parts, respectively adding the three parts into the base oil, and uniformly stirring to obtain the filling conditioner for the battery separator. The product provided by the invention is used for preparing the PE partition plate, and has the effects of protecting and helping mixing, maintaining the processing stability and improving the oxidation resistance of the PE partition plate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrical elements, in particular to a filling conditioner for battery separators and a preparation method thereof. BACKGROUND

[0002] Lead-acid batteries have long been developed and improved, and have an irreplaceable position in the secondary battery field due to low cost, high voltage and simple manufacturing process. The important component, microporous ultra-high molecular weight polyethylene separator (hereinafter referred to as PE separator), plays a multiple key role in the battery. It is placed between the positive and negative plates of the battery, and prevents active material migration and lead dendrite penetration through the microporous structure (pore size ≤4 μm), greatly reducing the risk of short circuit in the battery. Its transverse tensile strength is generally not less than 3 MPa, and can withstand a certain shear stress to ensure structural stability.

[0003] When preparing the PE separator, ultra-high molecular weight polyethylene powder (hereinafter referred to as UHMWPE powder), nano-silicon dioxide, conductive masterbatch and filling conditioner and other raw materials are blended, and then subjected to steps of extrusion molding, heat dissipation cooling, oil removal pore forming and cutting processing, to finally obtain the finished product PE separator. Among them, the nano-silicon dioxide added during mixing can improve the mechanical strength and porosity of the separator and enhance the electrolyte wettability; the conductive masterbatch is generally carbon black, which can adjust the conductivity of the PE separator and adjust the color; the filling conditioner plays a very key role, which can improve the flowability of the UHMWPE powder and nano-silicon dioxide blending system, cooperate with the solvent to form pores, enhance the mechanical properties of the PE separator, optimize the interface properties during blending of UHMWPE powder and nano-silicon dioxide, and improve the process safety, so the filling conditioner is one of the essential and crucial raw materials for preparing the PE separator.

[0004] The main substance (base oil) in the filling conditioner is naphthenic oil and paraffin oil, which has the characteristics of low pour point, high flash point and light color, maintains flowability at room temperature, ensures uniform mixing with UHMWPE powder, nano-silicon dioxide and other raw materials, and has less volatilization during high temperature extrusion, which can ensure production safety. And by blending other functional additives with the base oil, the comprehensive performance of the PE separator can be further improved, based on which researchers have conducted more in-depth research on the components of the filling conditioner. SUMMARY

[0005] In order to solve the above technical problems, the present application provides a filling conditioner for battery separators and a preparation method thereof.

[0006] In a first aspect, the application provides a filling conditioner for battery separators, which comprises, by weight, base oil and antioxidant active substance in a weight ratio of (450-500):(0.5-0.8); the base oil comprises naphthenic oil and paraffin oil, the base oil has a kinematic viscosity at 40℃ of 152-172 mm 2 / s and a flash point of 223-228℃; the antioxidant active substance comprises diphenyl hindered phenol antioxidant, phosphite antioxidant and carbon radical scavenger.

[0007] Preferably, the phosphite antioxidant is tris(2,4-di-tert-butylphenyl) phosphite.

[0008] Preferably, the carbon radical scavenger is 5,7-di-tert-butyl-3-(3,4-dimethylphenyl)benzofuran-2(3H)-one.

[0009] Preferably, the weight ratio of the diphenyl hindered phenol antioxidant, the phosphite antioxidant and the carbon radical scavenger is 75:(10-15):(10-15).

[0010] By adopting the above technical solution, the application uses the three compounds of diphenyl hindered phenol antioxidant, phosphite antioxidant and carbon radical scavenger as antioxidant active substance, and blends them with base oil according to a certain weight ratio, and the application also strictly controls the kinematic viscosity at 40℃ and the flash point of the base oil, so that a filling conditioner for battery separators with antioxidant property, good processing characteristics and excellent thermal stability is obtained. In the antioxidant active substance of the application, the arrangement of rigid molecular chains in the diphenyl hindered phenol antioxidant can improve the tensile strength and elastic modulus of the material, and has a good dispersibility in the material, the phosphite antioxidant can provide strong high-temperature stability, and the carbon radical scavenger can block the degradation process in the early stage of oxidation chain reaction, and forms a complementary effect with the diphenyl hindered phenol antioxidant and the phosphite antioxidant. By compounding the three compounds of diphenyl hindered phenol antioxidant, phosphite antioxidant and carbon radical scavenger, the application can realize the comprehensive optimization of antioxidant performance through mechanism complementation and synergistic effect.

[0011] Preferably, the weight ratio of the diphenyl hindered phenol antioxidant, the phosphite antioxidant and the carbon radical scavenger is 75:12:13.

[0012] By adopting the technical scheme, the weight ratio of the diphenyl hindered phenol antioxidant, the phosphite antioxidant and the carbon radical capturing agent is strictly controlled, the three optimization aspects of the improvement of the mechanical property, the antioxidant capacity and the high temperature stability of the antioxidant active substance are balanced as much as possible, and meanwhile, by controlling the amount of the carbon radical capturing agent, the complementary effect of the antioxidant improvement between the carbon radical capturing agent and the diphenyl hindered phenol antioxidant and the phosphite antioxidant is further improved.

[0013] Preferably, the kinematic viscosity of the naphthenic base oil at 40℃ is 616.8mm 2 / s, and the kinematic viscosity of the paraffinic base oil at 40℃ is 32.1mm 2 / s.

[0014] Preferably, the volume ratio of the naphthenic base oil and the paraffinic base oil is (65-70):(30-35).

[0015] Preferably, the volume ratio of the naphthenic base oil and the paraffinic base oil is 67:33.

[0016] The paraffinic base oil molecular chain is flexible, and forms a stable compatible system with the UHMWPE powder and the nano-silicon dioxide filler, reduces the mixing resistance, easily forms a continuous phase solvent channel, forms a uniform pore structure after elution, the naphthenic base oil can regulate the mechanical property of the PE separator, enhances the affinity with the trichloroethylene solvent, improves the oil washing efficiency, by adopting the technical scheme, the kinematic viscosity of the naphthenic base oil at 40℃ is strictly limited to 616.8mm 2 / s, the kinematic viscosity of the paraffinic base oil at 40℃ is 32.1mm 2 / s, and the kinematic viscosity of the naphthenic base oil at 40℃ is strictly controlled to 161.5±1mm 2 / s, at this time, the base oil has the best processing characteristics and thermal stability.

[0017] In the second aspect, the application provides a preparation method of the filling conditioner for the battery separator, including the following steps: S1, blending the naphthenic base oil and the paraffinic base oil at a rotating speed of 600-700r / min to obtain a base oil, for standby; S2, then blending the diphenyl hindered phenol antioxidant, the phosphite antioxidant and the carbon radical capturing agent to obtain an antioxidant active substance, for standby; S3, equally dividing the antioxidant active substance into three equal parts, and adding into the base oil respectively, and stirring uniformly to obtain the filling conditioner for the battery separator.

[0018] By adopting the technical scheme, the naphthenic oil and the paraffin oil are pre-blended to obtain base oil, then the diphenyl hindered phenol antioxidant, the phosphite antioxidant and the carbon radical capturing agent are blended to obtain antioxidant active substance, then the antioxidant active substance is added into the base oil in batches, so that the battery separator filling conditioner with the oxidation resistance, the good processing property and the excellent thermal stability can be prepared, the control of the kinematic viscosity and the flash point of the base oil at 40 DEG C can guarantee the production safety, the use of the naphthenic oil and the paraffin oil can ensure the uniform mixing with other raw materials, and the three kinds of antioxidant active substances are compounded to comprehensively optimize the oxidation resistance through the mechanism complementation and the synergistic effect.

[0019] Preferably, the step S3 is specifically: the antioxidant active substance is equally divided into three equal parts, one part is added into the base oil at a rotating speed of 350-400 r / min, the rotating speed is increased to 500-550 r / min after stirring for 5-10 min, the second part is added, the rotating speed is kept unchanged after stirring for 5-10 min, the third part is added, and the battery separator filling conditioner is obtained after stirring for 10-15 min.

[0020] By adopting the technical scheme, the antioxidant active substance is added into the base oil in three times with different rotating speeds and time intervals, the battery separator filling conditioner is prepared by the way of low-speed stirring for adding one part of the antioxidant active substance, then increasing the rotating speed to add the remaining two parts of the antioxidant active substance and segmenting stirring, so that the antioxidant active substance can be fully and uniformly mixed with the base oil, and the oxidation resistance, the processing property and the thermal stability of the battery separator filling conditioner can be further improved.

[0021] In summary, the application has the following beneficial technical effects: 1. The base oil and the antioxidant active substance with the specific weight ratio, and the base oil with the specific kinematic viscosity and the flash point are used in the application, so that the battery separator filling conditioner has the oxidation resistance, the good processing property and the excellent thermal stability; 2. The diphenyl hindered phenol antioxidant in the application can improve the tensile strength and the elastic modulus of the material, the phosphite antioxidant can provide strong high-temperature stability, the carbon radical capturing agent can block the degradation process in the early stage of the oxidation chain reaction, and the three kinds of substances can be compounded to comprehensively optimize the oxidation resistance of the battery separator filling conditioner; 3. The naphthenic oil and the paraffin oil in the base oil have the low pour point, the high flash point and the low colority, the use of the two kinds of oils can maintain the battery separator filling conditioner in the application to keep the flowability at room temperature and the low volatility during high-temperature extrusion, and can ensure the uniform mixing with other raw materials and guarantee the production safety. DETAILED DESCRIPTION

[0022] Material source The raw materials used in the application are all commercially available products except for special instructions, and are specifically: Naphthenic base oil, purchased from China Petroleum Lubricant Company, kinematic viscosity at 40℃ is 616.8mm 2 / s, kinematic viscosity at 100℃ is 19.7mm 2 / s, density 937.6kg / m 3 ; Paraffin base oil, purchased from China Petroleum Lubricant Company, kinematic viscosity at 40℃ is 32.1mm 2 / s, kinematic viscosity at 100℃ is 5.488mm 2 / s, density 867.2kg / m 3 ; Tris(2,4-di-tert-butylphenyl) phosphite, CAS No. 31570-04-4; 5,7-di-tert-butyl-3-(3,4-dimethylphenyl)benzofuran-2(3H)-one, CAS No. 164391-52-0; 3,5-bis(tert-butyl)-4-hydroxybenzaldehyde chloride, purchased from Yantai Shengkailun Biological Products Co., Ltd., CAS No. 3062-64-4; Preparation method of diphenyl hindered phenol antioxidant: Dissolve 250g 4,4'-diaminodiphenylmethane in 1L anhydrous acetonitrile, slowly drop 5L anhydrous acetonitrile and 223g 3,5-propionyl chloride mixed solution at 0℃, drop 0.2mol / L triethylamine acetonitrile solution under nitrogen protection, control the pH of the reaction system between 9-10, continue to stir for 2h after dropping, then warm the system to 55℃, constant temperature reaction for 24h; after the reaction is completed, remove the solvent and triethylamine under reduced pressure at 60℃, 133.3pa to obtain a light yellow crude product; dissolve the obtained solid in 3L dichloromethane, wash the above dichloromethane solution with 3.5L 5wt% NaHCO3 solution and 0.5mol / L hydrochloric acid solution respectively for three times, 8L saturated NaCl solution for two times, distill under reduced pressure at 60℃, 133.3pa to obtain a light yellow solid; dissolve the obtained product in ethanol, add an equal amount of 1mol / L NaOH solution, solid precipitates, continue to wash the obtained solid with a large amount of deionized water until neutral, dry in a 60℃ oven for 12h to obtain a light yellow solid powder, which is the diphenyl hindered phenol antioxidant.

[0023] The application will be further described in detail in combination with examples and comparative examples.

[0024] Example 1.1 A preparation method of a filling conditioner for a battery separator, comprising the following steps: S1, blend naphthenic base oil and paraffin base oil according to the volume ratio of 65:35 at the speed of 700 r / min to obtain base oil, ready for use; S2, blend diphenyl hindered phenol antioxidant, tris (2, 4-di-tert-butyl phenyl) phosphite and 5, 7-di-tert-butyl-3- (3, 4-dimethyl phenyl) benzofuran-2 (3H) -one according to the weight ratio of 75:5:20 to obtain antioxidant active substance, ready for use; S3, divide the antioxidant active substance into 3 equal parts, and add 1 part to the base oil at the speed of 400 r / min, stir for 10 min, then increase the speed to 500 r / min, add the second part of the base oil, stir for 5 min, then keep the speed unchanged and add the third part of the base oil, stir for 15 min to obtain the filling conditioner for battery separator, control the weight ratio of base oil to antioxidant active substance to be 450:0.8.

[0025] Example 1.2 A preparation method of a filling conditioner for battery separator, comprising the following steps: S1, blend naphthenic base oil and paraffin base oil according to the volume ratio of 70:30 at the speed of 600 r / min to obtain base oil, ready for use; S2, blend diphenyl hindered phenol antioxidant, tris (2, 4-di-tert-butyl phenyl) phosphite and 5, 7-di-tert-butyl-3- (3, 4-dimethyl phenyl) benzofuran-2 (3H) -one according to the weight ratio of 75:20:5 to obtain antioxidant active substance, ready for use; S3, divide the antioxidant active substance into 3 equal parts, and add 1 part to the base oil at the speed of 350 r / min, stir for 5 min, then increase the speed to 550 r / min, add the second part of the base oil, stir for 10 min, then keep the speed unchanged and add the third part of the base oil, stir for 10 min to obtain the filling conditioner for battery separator, control the weight ratio of base oil to antioxidant active substance to be 500:0.5.

[0026] Comparative Example 1.1 The difference from Example 1.1 is that in step S2, the weight ratio of diphenyl hindered phenol antioxidant, tris (2, 4-di-tert-butyl phenyl) phosphite and 5, 7-di-tert-butyl-3- (3, 4-dimethyl phenyl) benzofuran-2 (3H) -one is still 5:20, and the rest is the same as Example 1.1.

[0027] Comparative Example 1.2 The difference from Example 1.1 is that in step S2, the weight ratio of the tri(2,4-di-tert-butylphenyl) phosphite, the diphenyl hindered phenol antioxidant and the 5,7-di-tert-butyl-3-(3,4-dimethylphenyl)benzofuran-2(3H)-one is still 75:20, and the rest is the same as Example 1.1.

[0028] Comparative Example 1.3 The difference from Example 1.1 is that in step S2, the weight ratio of the 5,7-di-tert-butyl-3-(3,4-dimethylphenyl)benzofuran-2(3H)-one, the diphenyl hindered phenol antioxidant and the tri(2,4-di-tert-butylphenyl) phosphite is still 75:5, and the rest is the same as Example 1.1.

[0029] Example 2.1 A method for preparing a filling conditioner for a battery separator, the difference from Example 1.1 is that in step S2, the weight ratio of the diphenyl hindered phenol antioxidant, the tri(2,4-di-tert-butylphenyl) phosphite and the 5,7-di-tert-butyl-3-(3,4-dimethylphenyl)benzofuran-2(3H)-one is 75:10:15, and the rest is the same as Example 1.1.

[0030] Example 2.2 A method for preparing a filling conditioner for a battery separator, the difference from Example 1.1 is that in step S2, the weight ratio of the diphenyl hindered phenol antioxidant, the tri(2,4-di-tert-butylphenyl) phosphite and the 5,7-di-tert-butyl-3-(3,4-dimethylphenyl)benzofuran-2(3H)-one is 75:15:10, and the rest is the same as Example 1.1.

[0031] Example 2.3 A method for preparing a filling conditioner for a battery separator, the difference from Example 1.1 is that in step S2, the weight ratio of the diphenyl hindered phenol antioxidant, the tri(2,4-di-tert-butylphenyl) phosphite and the 5,7-di-tert-butyl-3-(3,4-dimethylphenyl)benzofuran-2(3H)-one is 75:12:13, and the rest is the same as Example 1.1.

[0032] Example 2.4 A method for preparing a filling conditioner for a battery separator, the difference from Example 1.1 is that in step S2, the weight ratio of the diphenyl hindered phenol antioxidant, the tri(2,4-di-tert-butylphenyl) phosphite and the 5,7-di-tert-butyl-3-(3,4-dimethylphenyl)benzofuran-2(3H)-one is 75:13:12, and the rest is the same as Example 1.1.

[0033] Example 3.1 A method for preparing a filling conditioner for a battery separator, which is different from Example 2.3 in that in step S1, the volume ratio of naphthenic oil and paraffin oil is 66:34, and the rest is the same as Example 2.3.

[0034] Example 3.2 A method for preparing a filling conditioner for a battery separator, which is different from Example 2.3 in that in step S1, the volume ratio of naphthenic oil and paraffin oil is 67:33, and the rest is the same as Example 2.3.

[0035] Example 3.3 A method for preparing a filling conditioner for a battery separator, which is different from Example 2.3 in that in step S1, the volume ratio of naphthenic oil and paraffin oil is 68:32, and the rest is the same as Example 2.3.

[0036] Example 3.4 A method for preparing a filling conditioner for a battery separator, which is different from Example 2.3 in that in step S1, the volume ratio of naphthenic oil and paraffin oil is 69:31, and the rest is the same as Example 2.3.

[0037] Performance test Sample preparation: The filling conditioner for battery separator prepared by the examples and comparative examples is blended with UHMWPE powder and nano-silicon dioxide according to a weight ratio of 450:100:0.25, and the battery separator filling conditioner is eluted with trichloroethylene, and finally the battery separator sample with a thickness of 0.5mm is prepared; According to the records and requirements in GB / T 28535-2020 "Lead-acid battery separator", GB / T 1040.3-2006 "Determination of tensile properties of plastics" and IEC 60896-21, the following tests are carried out: 1. The battery separator sample is soaked in a mixed oxidizing solution of sulfuric acid solution (density 1.3g / cm³) and hydrogen peroxide (0.1mol / L) at 80℃, and the mass loss rate% is detected after 24 hours of treatment; 2. The volume shrinkage rate% in the horizontal and vertical directions is measured after 1 hour of treatment in an 80℃ oven, and the tensile strength (MPa) in the horizontal and vertical directions at room temperature is measured; 3. The porosity% is measured.

[0038] Table 1 Data recording table

[0039] Data analysis: From Table 1, it can be seen that the filling conditioner for battery separator prepared in the present application examples 1.1-1.2 can maintain the thermal oxidative treatment mass loss rate of the battery separator sample at 2.5-2.8%, the transverse volume shrinkage rate at 1.7-1.8%, the longitudinal volume shrinkage rate at 2.8%, the transverse tensile strength at 8.3-8.5 MPa, the longitudinal tensile strength at 12.6-12.7 MPa, and the porosity at 56-58%, all of which meet the quality standards of PE separator, and compared with Comparative Examples 1.1-1.3, the examples 1.1-1.2 can reduce the thermal oxidative treatment mass loss rate of the battery separator sample by 26-32%, proving that the present application can realize the comprehensive optimization of antioxidant performance by mechanism complementation and synergistic effect of the three compounds of diphenyl hindered phenolic antioxidant, phosphite antioxidant and carbon radical scavenger, and at the same time, the mechanical properties and porosity of the battery separator sample are not affected, proving that the filling conditioner of the present application has antioxidant property, good processing characteristics and excellent thermal stability.

[0040] In Comparative Examples 1.1-1.3, the diphenyl hindered phenolic antioxidant, phosphite antioxidant and carbon radical scavenger were removed respectively, and the results showed that the thermal oxidative treatment mass loss rate of the battery separator sample was greatly improved, proving that the diphenyl hindered phenolic antioxidant in the present application can improve the tensile strength and elastic modulus of the material, the phosphite antioxidant provides strong high-temperature stability, and the carbon radical scavenger blocks the degradation process in the early stage of oxidation chain reaction, and the three compounds realize the comprehensive optimization of antioxidant performance.

[0041] In Examples 2.1-2.4, the weight ratio of diphenyl hindered phenolic antioxidant, phosphite antioxidant and carbon radical scavenger was changed, and the results showed that the mass loss rate of Example 2.3 was the lowest, and the transverse volume shrinkage rate and longitudinal volume shrinkage rate were lower, and the transverse tensile strength and longitudinal tensile strength were higher, proving that by strictly controlling the weight ratio of diphenyl hindered phenolic antioxidant, phosphite antioxidant and carbon radical scavenger, the present application can balance the three optimization aspects of the antioxidant active substance, i.e. the improvement of mechanical properties, antioxidant capacity and high-temperature stability, and by controlling the amount of carbon radical scavenger, the complementary effect of the antioxidant improvement between the diphenyl hindered phenolic antioxidant and the phosphite antioxidant and the carbon radical scavenger is further improved.

[0042] In Examples 3.1-3.4, the volume ratio of naphthenic base oil and paraffin base oil in the base oil was changed, and the results showed that the transverse volume shrinkage rate and longitudinal volume shrinkage rate of Example 3.2 were lower, the transverse tensile strength and longitudinal tensile strength were higher, and the porosity was as high as 60%, proving that by strictly limiting the volume ratio of the two, the present application can strictly control the kinematic viscosity of the base oil at 40°C to 161.5±1 mm 2 / s, at this time the base oil has the best processing characteristics and thermal stability, higher use stability in use, and steady optimization of various performances.

[0043] The embodiments of the present specific implementation are the preferred embodiments of the present application, and do not limit the protection scope of the present application, so that: any equivalent changes made according to the structure, shape, principle of the present application should be covered within the protection scope of the present application.

Claims

1. A filling conditioner for battery separators, characterized in that: The raw materials used include base oil and antioxidant active substances in a weight ratio of (450-500): (0.5-0.8) by weight; the base oil includes cycloalkyl oil and paraffin base oil, and the kinematic viscosity of the base oil at 40°C is 152-172mm 2 / s, and a flash point of 223-228°C; the antioxidant active substance includes a diphenyl hindered phenol antioxidant, a phosphite antioxidant, and a carbon free radical scavenger.

2. A filling conditioner for battery separators according to claim 1, characterized in that: The phosphite antioxidant is tris(2,4-di-tert-butylphenyl) phosphite.

3. A filling conditioner for battery separators according to claim 1, characterized in that: The carbon free radical scavenger is 5,7-di-tert-butyl-3-(3,4-dimethylphenyl)benzofuran-2(3H)-one.

4. A filling conditioner for battery separators according to claim 1, characterized in that: The weight ratio of the diphenyl hindered phenol antioxidant, the phosphite antioxidant and the carbon free radical scavenger is 75:(10-15):(10-15).

5. A filling conditioner for battery separators according to claim 4, characterized in that: The weight ratio of the diphenyl hindered phenol antioxidant, the phosphite antioxidant and the carbon radical scavenger is 75:12:

13.

6. A filling conditioner for battery separators according to claim 1, characterized in that: The kinematic viscosity of the naphthenic oil at 40°C is 616.8 mm 2 / s, the kinematic viscosity of paraffin-based oil at 40°C is 32.1 mm 2 / s.

7. A filling conditioner for battery separators according to claim 6, characterized in that: The volume ratio of the cycloalkyl oil to the paraffinic oil is (65-70):(30-35).

8. A filling conditioner for battery separators according to claim 7, characterized in that: The volume ratio of the naphthenic oil to the paraffinic oil is 67:

33.

9. A method for preparing a filling conditioner for battery separators according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Blending naphthenic oil and paraffinic oil at a rotation speed of 600-700 r / min to obtain base oil for standby use; S2, then blending the diphenyl hindered phenol antioxidant, the phosphite antioxidant and the carbon free radical scavenger to obtain an antioxidant active substance for later use; S3. Divide the antioxidant active substance into three equal parts, add them into the base oil respectively, and stir them evenly to obtain a filling conditioner for battery separators.

10. The method for preparing a filling conditioner for battery separators according to claim 9, characterized in that: The step S3 specifically comprises: dividing the antioxidant active substance into three equal parts, adding one part thereof to the base oil at a rotation speed of 350-400 r / min, stirring for 5-10 minutes, increasing the rotation speed to 500-550 r / min, adding the second part of the base oil, stirring for 5-10 minutes, and then adding the third part of the base oil while maintaining the rotation speed unchanged, and stirring for 10-15 minutes to obtain the filling conditioner for the battery separator.

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